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Sample records for actions neural evidence

  1. Body-specific motor imagery of hand actions: neural evidence from right- and left-handers

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    Roel M Willems

    2009-11-01

    Full Text Available If motor imagery uses neural structures involved in action execution, then the neural correlates of imagining an action should differ between individuals who tend to execute the action differently. Here we report fMRI data showing that motor imagery is influenced by the way people habitually perform motor actions with their particular bodies; that is, motor imagery is ‘body-specific’ (Casasanto, 2009. During mental imagery for complex hand actions, activation of cortical areas involved in motor planning and execution was left-lateralized in right-handers but right-lateralized in left-handers. We conclude that motor imagery involves the generation of an action plan that is grounded in the participant’s motor habits, not just an abstract representation at the level of the action’s goal. People with different patterns of motor experience form correspondingly different neurocognitive representations of imagined actions.

  2. Neural evidence for the intrinsic value of action as motivation for behavior.

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    Miura, Naoki; Tanabe, Hiroki C; Sasaki, Akihiro; Harada, Tokiko; Sadato, Norihiro

    2017-04-07

    The intrinsic value of an action refers to the inherent sense that experiencing a behavior is enjoyable even if it has no explicit outcome. Previous research has suggested that a common valuation mechanism within the reward network may be responsible for processing the intrinsic value of achieving both the outcome and external reward. However, how the intrinsic value of action is neurally represented remains unknown. We hypothesized that the intrinsic value of action is determined by an action-outcome contingency indicating the behavior is controllable and that the outcome of the action can be evaluated by this feedback. Consequently, the reward network should be activated, reflecting the generation of the intrinsic value of action. To test this hypothesis, we conducted a functional magnetic resonance imaging (fMRI) investigation of a stopwatch game in which the action-outcome contingency was manipulated. This experiment involved 36 healthy volunteers and four versions of a stopwatch game that manipulated controllability (the feeling that participants were controlling the stopwatch themselves) and outcome (a signal allowing participants to see the result of their action). A free-choice experiment was administered after the fMRI to explore preference levels for each game. The results showed that the stopwatch game with the action-outcome contingency evoked a greater degree of enjoyment because the participants chose this condition over those that lacked such a contingency. The ventral striatum and midbrain were activated only when action-outcome contingency was present. Thus, the intrinsic value of action was represented by an increase in ventral striatal and midbrain activation.

  3. Translating working memory into action: behavioral and neural evidence for using motor representations in encoding visuo-spatial sequences.

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    Langner, Robert; Sternkopf, Melanie A; Kellermann, Tanja S; Grefkes, Christian; Kurth, Florian; Schneider, Frank; Zilles, Karl; Eickhoff, Simon B

    2014-07-01

    The neurobiological organization of action-oriented working memory is not well understood. To elucidate the neural correlates of translating visuo-spatial stimulus sequences into delayed (memory-guided) sequential actions, we measured brain activity using functional magnetic resonance imaging while participants encoded sequences of four to seven dots appearing on fingers of a left or right schematic hand. After variable delays, sequences were to be reproduced with the corresponding fingers. Recall became less accurate with longer sequences and was initiated faster after long delays. Across both hands, encoding and recall activated bilateral prefrontal, premotor, superior and inferior parietal regions as well as the basal ganglia, whereas hand-specific activity was found (albeit to a lesser degree during encoding) in contralateral premotor, sensorimotor, and superior parietal cortex. Activation differences after long versus short delays were restricted to motor-related regions, indicating that rehearsal during long delays might have facilitated the conversion of the memorandum into concrete motor programs at recall. Furthermore, basal ganglia activity during encoding selectively predicted correct recall. Taken together, the results suggest that to-be-reproduced visuo-spatial sequences are encoded as prospective action representations (motor intentions), possibly in addition to retrospective sensory codes. Overall, our study supports and extends multi-component models of working memory, highlighting the notion that sensory input can be coded in multiple ways depending on what the memorandum is to be used for.

  4. Musical experts recruit action-related neural structures in harmonic anomaly detection: Evidence for embodied cognition in expertise

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    Sherwin, Jason; Sajda, Paul

    2013-01-01

    Humans are extremely good at detecting anomalies in sensory input. For example, while listening to a piece of Western-style music, an anomalous key change or an out-of-key pitch is readily apparent, even to the non-musician. In this paper we investigate differences between musical experts and non-experts during musical anomaly detection. Specifically, we analyzed the electroencephalograms (EEG) of five expert cello players and five non-musicians while they listened to excerpts of J.S. Bach’s Prelude from Cello Suite No.1. All subjects were familiar with the piece, though experts also had extensive experience playing the piece. Subjects were told that anomalous musical events (AMEs) could occur at random within the excerpts of the piece and were told to report the number of AMEs after each excerpt. Furthermore, subjects were instructed to remain still while listening to the excerpts and their lack of movement was verified via visual and EEG monitoring. Experts had significantly better behavioral performance (i.e. correctly reporting AME counts) than non-experts, though both groups had mean accuracies greater than 80%. These group differences were also reflected in the EEG correlates of key-change detection post-stimulus, with experts showing more significant, greater magnitude, longer periods of and earlier peaks in condition-discriminating EEG activity than novices. Using the timing of the maximum discriminating neural correlates, we performed source reconstruction and compared significant differences between cellists and non-musicians. We found significant differences that included a slightly right lateralized motor and frontal source distribution. The right lateralized motor activation is consistent with the cortical representation of the left hand – i.e. the hand a cellist would use, while playing, to generate the anomalous key-changes. In general, these results suggest that sensory anomalies detected by experts may in fact be partially a result of an

  5. The neural basis of body form and body action agnosia.

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    Moro, Valentina; Urgesi, Cosimo; Pernigo, Simone; Lanteri, Paola; Pazzaglia, Mariella; Aglioti, Salvatore Maria

    2008-10-23

    Visual analysis of faces and nonfacial body stimuli brings about neural activity in different cortical areas. Moreover, processing body form and body action relies on distinct neural substrates. Although brain lesion studies show specific face processing deficits, neuropsychological evidence for defective recognition of nonfacial body parts is lacking. By combining psychophysics studies with lesion-mapping techniques, we found that lesions of ventromedial, occipitotemporal areas induce face and body recognition deficits while lesions involving extrastriate body area seem causatively associated with impaired recognition of body but not of face and object stimuli. We also found that body form and body action recognition deficits can be double dissociated and are causatively associated with lesions to extrastriate body area and ventral premotor cortex, respectively. Our study reports two category-specific visual deficits, called body form and body action agnosia, and highlights their neural underpinnings.

  6. Sports experience changes the neural processing of action language.

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    Beilock, Sian L; Lyons, Ian M; Mattarella-Micke, Andrew; Nusbaum, Howard C; Small, Steven L

    2008-09-09

    Experience alters behavior by producing enduring changes in the neural processes that support performance. For example, performing a specific action improves the execution of that action via changes in associated sensory and motor neural circuitry, and experience using language improves language comprehension by altering the anatomy and physiology of perisylvian neocortical brain regions. Here we provide evidence that specialized (sports) motor experience enhances action-related language understanding by recruitment of left dorsal lateral premotor cortex, a region normally devoted to higher-level action selection and implementation-even when there is no intention to perform a real action. Experience playing and watching sports has enduring effects on language understanding by changing the neural networks that subserve comprehension to incorporate areas active in performing sports skills. Without such experience, sport novices recruit lower-level sensory-motor regions, thought to support the instantiation of movement, during language processing, and activity in primary motor areas does not help comprehension. Thus, the language system is sufficiently plastic and dynamic to encompass expertise-related neural recruitment outside core language networks.

  7. Marketing actions can modulate neural representations of experienced pleasantness.

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    Plassmann, Hilke; O'Doherty, John; Shiv, Baba; Rangel, Antonio

    2008-01-22

    Despite the importance and pervasiveness of marketing, almost nothing is known about the neural mechanisms through which it affects decisions made by individuals. We propose that marketing actions, such as changes in the price of a product, can affect neural representations of experienced pleasantness. We tested this hypothesis by scanning human subjects using functional MRI while they tasted wines that, contrary to reality, they believed to be different and sold at different prices. Our results show that increasing the price of a wine increases subjective reports of flavor pleasantness as well as blood-oxygen-level-dependent activity in medial orbitofrontal cortex, an area that is widely thought to encode for experienced pleasantness during experiential tasks. The paper provides evidence for the ability of marketing actions to modulate neural correlates of experienced pleasantness and for the mechanisms through which the effect operates.

  8. Brain and language: evidence for neural multifunctionality.

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    Cahana-Amitay, Dalia; Albert, Martin L

    2014-01-01

    This review paper presents converging evidence from studies of brain damage and longitudinal studies of language in aging which supports the following thesis: the neural basis of language can best be understood by the concept of neural multifunctionality. In this paper the term "neural multifunctionality" refers to incorporation of nonlinguistic functions into language models of the intact brain, reflecting a multifunctional perspective whereby a constant and dynamic interaction exists among neural networks subserving cognitive, affective, and praxic functions with neural networks specialized for lexical retrieval, sentence comprehension, and discourse processing, giving rise to language as we know it. By way of example, we consider effects of executive system functions on aspects of semantic processing among persons with and without aphasia, as well as the interaction of executive and language functions among older adults. We conclude by indicating how this multifunctional view of brain-language relations extends to the realm of language recovery from aphasia, where evidence of the influence of nonlinguistic factors on the reshaping of neural circuitry for aphasia rehabilitation is clearly emerging.

  9. The time course of auditory-visual processing of speech and body actions: evidence for the simultaneous activation of an extended neural network for semantic processing.

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    Meyer, Georg F; Harrison, Neil R; Wuerger, Sophie M

    2013-08-01

    An extensive network of cortical areas is involved in multisensory object and action recognition. This network draws on inferior frontal, posterior temporal, and parietal areas; activity is modulated by familiarity and the semantic congruency of auditory and visual component signals even if semantic incongruences are created by combining visual and auditory signals representing very different signal categories, such as speech and whole body actions. Here we present results from a high-density ERP study designed to examine the time-course and source location of responses to semantically congruent and incongruent audiovisual speech and body actions to explore whether the network involved in action recognition consists of a hierarchy of sequentially activated processing modules or a network of simultaneously active processing sites. We report two main results:1) There are no significant early differences in the processing of congruent and incongruent audiovisual action sequences. The earliest difference between congruent and incongruent audiovisual stimuli occurs between 240 and 280 ms after stimulus onset in the left temporal region. Between 340 and 420 ms, semantic congruence modulates responses in central and right frontal areas. Late differences (after 460 ms) occur bilaterally in frontal areas.2) Source localisation (dipole modelling and LORETA) reveals that an extended network encompassing inferior frontal, temporal, parasaggital, and superior parietal sites are simultaneously active between 180 and 420 ms to process auditory–visual action sequences. Early activation (before 120 ms) can be explained by activity in mainly sensory cortices. . The simultaneous activation of an extended network between 180 and 420 ms is consistent with models that posit parallel processing of complex action sequences in frontal, temporal and parietal areas rather than models that postulate hierarchical processing in a sequence of brain regions. Copyright © 2013 Elsevier Ltd. All

  10. Neural basis of understanding communicative actions: Changes associated with knowing the actor's intention and the meanings of the actions.

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    Möttönen, Riikka; Farmer, Harry; Watkins, Kate E

    2016-01-29

    People can communicate by using hand actions, e.g., signs. Understanding communicative actions requires that the observer knows that the actor has an intention to communicate and the meanings of the actions. Here, we investigated how this prior knowledge affects processing of observed actions. We used functional MRI to determine changes in action processing when non-signers were told that the observed actions are communicative (i.e., signs) and learned the meanings of half of the actions. Processing of hand actions activated the left and right inferior frontal gyrus (IFG, BA 44 and 45) when the communicative intention of the actor was known, even when the meanings of the actions remained unknown. These regions were not active when the observers did not know about the communicative nature of the hand actions. These findings suggest that the left and right IFG play a role in understanding the intention of the actor, but do not process visuospatial features of the communicative actions. Knowing the meanings of the hand actions further enhanced activity in the anterior part of the IFG (BA 45), the inferior parietal lobule and posterior inferior and middle temporal gyri in the left hemisphere. These left-hemisphere language regions could provide a link between meanings and observed actions. In sum, the findings provide evidence for the segregation of the networks involved in the neural processing of visuospatial features of communicative hand actions and those involved in understanding the actor's intention and the meanings of the actions.

  11. Neural Behavior Chain Learning of Mobile Robot Actions

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    Lejla Banjanovic-Mehmedovic

    2012-01-01

    Full Text Available This paper presents a visual/motor behavior learning approach, based on neural networks. We propose Behavior Chain Model (BCM in order to create a way of behavior learning. Our behavior-based system evolution task is a mobile robot detecting a target and driving/acting towards it. First, the mapping relations between the image feature domain of the object and the robot action domain are derived. Second, a multilayer neural network for offline learning of the mapping relations is used. This learning structure through neural network training process represents a connection between the visual perceptions and motor sequence of actions in order to grip a target. Last, using behavior learning through a noticed action chain, we can predict mobile robot behavior for a variety of similar tasks in similar environment. Prediction results suggest that the methodology is adequate and could be recognized as an idea for designing different mobile robot behaviour assistance.

  12. A continuous-time neural model for sequential action.

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    Kachergis, George; Wyatte, Dean; O'Reilly, Randall C; de Kleijn, Roy; Hommel, Bernhard

    2014-11-01

    Action selection, planning and execution are continuous processes that evolve over time, responding to perceptual feedback as well as evolving top-down constraints. Existing models of routine sequential action (e.g. coffee- or pancake-making) generally fall into one of two classes: hierarchical models that include hand-built task representations, or heterarchical models that must learn to represent hierarchy via temporal context, but thus far lack goal-orientedness. We present a biologically motivated model of the latter class that, because it is situated in the Leabra neural architecture, affords an opportunity to include both unsupervised and goal-directed learning mechanisms. Moreover, we embed this neurocomputational model in the theoretical framework of the theory of event coding (TEC), which posits that actions and perceptions share a common representation with bidirectional associations between the two. Thus, in this view, not only does perception select actions (along with task context), but actions are also used to generate perceptions (i.e. intended effects). We propose a neural model that implements TEC to carry out sequential action control in hierarchically structured tasks such as coffee-making. Unlike traditional feedforward discrete-time neural network models, which use static percepts to generate static outputs, our biological model accepts continuous-time inputs and likewise generates non-stationary outputs, making short-timescale dynamic predictions.

  13. Neural mirroring and social interaction: Motor system involvement during action observation relates to early peer cooperation.

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    Endedijk, H M; Meyer, M; Bekkering, H; Cillessen, A H N; Hunnius, S

    2017-04-01

    Whether we hand over objects to someone, play a team sport, or make music together, social interaction often involves interpersonal action coordination, both during instances of cooperation and entrainment. Neural mirroring is thought to play a crucial role in processing other's actions and is therefore considered important for social interaction. Still, to date, it is unknown whether interindividual differences in neural mirroring play a role in interpersonal coordination during different instances of social interaction. A relation between neural mirroring and interpersonal coordination has particularly relevant implications for early childhood, since successful early interaction with peers is predictive of a more favorable social development. We examined the relation between neural mirroring and children's interpersonal coordination during peer interaction using EEG and longitudinal behavioral data. Results showed that 4-year-old children with higher levels of motor system involvement during action observation (as indicated by lower beta-power) were more successful in early peer cooperation. This is the first evidence for a relation between motor system involvement during action observation and interpersonal coordination during other instances of social interaction. The findings suggest that interindividual differences in neural mirroring are related to interpersonal coordination and thus successful social interaction. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Neural representation of the sensorimotor speech-action-repository

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    Cornelia eEckers

    2013-04-01

    Full Text Available A speech-action-repository (SAR or mental syllabary has been proposed as a central module for sensorimotor processing of syllables. In this approach, syllables occurring frequently within language are assumed to be stored as holistic sensorimotor patterns, while non-frequent syllables need to be assembled from sub-syllabic units. Thus, frequent syllables are processed efficiently and quickly during production or perception by a direct activation of their sensorimotor patterns. Whereas several behavioral psycholinguistic studies provided evidence in support of the existence of a syllabary, fMRI studies have failed to demonstrate its neural reality. In the present fMRI study a reaction paradigm using homogeneous vs. heterogeneous syllable blocks are used during overt vs. covert speech production and auditory vs. visual presentation modes. Two complementary data analyses were performed: (1 in a logical conjunction, activation for syllable processing independent of input modality and response mode was assessed, in order to support the assumption of existence of a supramodal hub within a SAR. (2 In addition priming effects in the BOLD response in homogeneous vs. heterogeneous blocks were measured in order to identify brain regions, which indicate reduced activity during multiple production/perception repetitions of a specific syllable in order to determine state maps. Auditory-visual conjunction analysis revealed an activation network comprising bilateral precentral gyrus and left inferior frontal gyrus (area 44. These results are compatible with the notion of a supramodal hub within the SAR. The main effect of homogeneity priming revealed an activation pattern of areas within frontal, temporal, and parietal lobe. These findings are taken to represent sensorimotor state maps of the SAR. In conclusion, the present study provided preliminary evidence for a SAR.

  15. The neural basis of predicting the outcomes of planned actions

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    Andrew eJahn

    2011-11-01

    Full Text Available A key feature of human intelligence is the ability to predict the outcomes of one’s own actions prior to executing them. Action values are thought to be represented in part in the dorsal and ventral medial prefrontal cortex, yet current studies have focused on the value of executed actions rather than the anticipated value of a planned action. Thus, little is known about the neural basis of how individuals think (or fail to think about their actions and the potential consequences before they act. We scanned individuals with fMRI while they thought about performing actions that they knew would likely be correct or incorrect. Here we show that merely imagining an error, as opposed to imagining a correct outcome, increases activity in the dorsal anterior cingulate cortex, independently of subsequent actions. This activity overlaps with regions that respond to actual error commission. The findings show a distinct network that signals the prospective outcomes of one’s planned actions. A number of clinical disorders such as schizophrenia and drug abuse involve a failure to take the potential consequences of an action into account prior to acting. Our results thus suggest how dysfunctions of the medial prefrontal cortex may contribute to such failures.

  16. Neural dynamics of learning sound-action associations.

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    Adam McNamara

    Full Text Available A motor component is pre-requisite to any communicative act as one must inherently move to communicate. To learn to make a communicative act, the brain must be able to dynamically associate arbitrary percepts to the neural substrate underlying the pre-requisite motor activity. We aimed to investigate whether brain regions involved in complex gestures (ventral pre-motor cortex, Brodmann Area 44 were involved in mediating association between novel abstract auditory stimuli and novel gestural movements. In a functional resonance imaging (fMRI study we asked participants to learn associations between previously unrelated novel sounds and meaningless gestures inside the scanner. We use functional connectivity analysis to eliminate the often present confound of 'strategic covert naming' when dealing with BA44 and to rule out effects of non-specific reductions in signal. Brodmann Area 44, a region incorporating Broca's region showed strong, bilateral, negative correlation of BOLD (blood oxygen level dependent response with learning of sound-action associations during data acquisition. Left-inferior-parietal-lobule (l-IPL and bilateral loci in and around visual area V5, right-orbital-frontal-gyrus, right-hippocampus, left-para-hippocampus, right-head-of-caudate, right-insula and left-lingual-gyrus also showed decreases in BOLD response with learning. Concurrent with these decreases in BOLD response, an increasing connectivity between areas of the imaged network as well as the right-middle-frontal-gyrus with rising learning performance was revealed by a psychophysiological interaction (PPI analysis. The increasing connectivity therefore occurs within an increasingly energy efficient network as learning proceeds. Strongest learning related connectivity between regions was found when analysing BA44 and l-IPL seeds. The results clearly show that BA44 and l-IPL is dynamically involved in linking gesture and sound and therefore provides evidence that one of

  17. Neural correlates of transitive and intransitive action imitation: An investigation using voxel-based morphometry

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    Carolina Bonivento

    2014-01-01

    Full Text Available The ability to reproduce visually presented actions has been studied through neuropsychological observations of patients with ideomotor apraxia. These studies include attempts to understand the neural basis of action reproduction based on lesion–symptom mapping in different patient groups. While there is a convergence of evidence that areas in the parietal and frontal lobes within the left hemisphere are involved in the imitation of a variety of actions, questions remain about whether the results generalize beyond the imitation of tool use and whether the presence of a strong grasp component of the action is critical. Here we used voxel-based lesion–symptom mapping to assess the neural substrates of imitating meaningful (familiar, MF and meaningless (unfamiliar, ML tool-related (transitive and non-tool related (intransitive actions. The analysis showed that the left parietal cortex was involved in the imitation of transitive gestures, regardless of whether they were meaningful or not. In addition there was poor reproduction of meaningless actions (both transitive and intransitive following damage of the right frontal cortex. These findings suggest a role of right frontal regions in processing of unfamiliar actions.

  18. Neural correlates of transitive and intransitive action imitation: an investigation using voxel-based morphometry.

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    Bonivento, Carolina; Rothstein, Pia; Humphreys, Glyn; Chechlacz, Magdalena

    2014-01-01

    The ability to reproduce visually presented actions has been studied through neuropsychological observations of patients with ideomotor apraxia. These studies include attempts to understand the neural basis of action reproduction based on lesion-symptom mapping in different patient groups. While there is a convergence of evidence that areas in the parietal and frontal lobes within the left hemisphere are involved in the imitation of a variety of actions, questions remain about whether the results generalize beyond the imitation of tool use and whether the presence of a strong grasp component of the action is critical. Here we used voxel-based lesion-symptom mapping to assess the neural substrates of imitating meaningful (familiar, MF) and meaningless (unfamiliar, ML) tool-related (transitive) and non-tool related (intransitive) actions. The analysis showed that the left parietal cortex was involved in the imitation of transitive gestures, regardless of whether they were meaningful or not. In addition there was poor reproduction of meaningless actions (both transitive and intransitive) following damage of the right frontal cortex. These findings suggest a role of right frontal regions in processing of unfamiliar actions.

  19. A Neural Dynamic Model Generates Descriptions of Object-Oriented Actions.

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    Richter, Mathis; Lins, Jonas; Schöner, Gregor

    2017-01-01

    Describing actions entails that relations between objects are discovered. A pervasively neural account of this process requires that fundamental problems are solved: the neural pointer problem, the binding problem, and the problem of generating discrete processing steps from time-continuous neural processes. We present a prototypical solution to these problems in a neural dynamic model that comprises dynamic neural fields holding representations close to sensorimotor surfaces as well as dynamic neural nodes holding discrete, language-like representations. Making the connection between these two types of representations enables the model to describe actions as well as to perceptually ground movement phrases-all based on real visual input. We demonstrate how the dynamic neural processes autonomously generate the processing steps required to describe or ground object-oriented actions. By solving the fundamental problems of neural pointing, binding, and emergent discrete processing, the model may be a first but critical step toward a systematic neural processing account of higher cognition.

  20. Neural networks for harmonic structure in music perception and action.

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    Bianco, R; Novembre, G; Keller, P E; Kim, Seung-Goo; Scharf, F; Friederici, A D; Villringer, A; Sammler, D

    2016-11-15

    The ability to predict upcoming structured events based on long-term knowledge and contextual priors is a fundamental principle of human cognition. Tonal music triggers predictive processes based on structural properties of harmony, i.e., regularities defining the arrangement of chords into well-formed musical sequences. While the neural architecture of structure-based predictions during music perception is well described, little is known about the neural networks for analogous predictions in musical actions and how they relate to auditory perception. To fill this gap, expert pianists were presented with harmonically congruent or incongruent chord progressions, either as musical actions (photos of a hand playing chords) that they were required to watch and imitate without sound, or in an auditory format that they listened to without playing. By combining task-based functional magnetic resonance imaging (fMRI) with functional connectivity at rest, we identified distinct sub-regions in right inferior frontal gyrus (rIFG) interconnected with parietal and temporal areas for processing action and audio sequences, respectively. We argue that the differential contribution of parietal and temporal areas is tied to motoric and auditory long-term representations of harmonic regularities that dynamically interact with computations in rIFG. Parsing of the structural dependencies in rIFG is co-determined by both stimulus- or task-demands. In line with contemporary models of prefrontal cortex organization and dual stream models of visual-spatial and auditory processing, we show that the processing of musical harmony is a network capacity with dissociated dorsal and ventral motor and auditory circuits, which both provide the infrastructure for predictive mechanisms optimising action and perception performance. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Sight and sound of actions share a common neural network.

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    Giusti, M A; Bozzacchi, C; Pizzamiglio, L; Di Russo, F

    2010-11-01

    The mirror-neuron system (MNS) connects sensory information that describes an action with a motor plan for performing that action. Recently, studies using the repetition-suppression paradigm have shown that strong activation occurs in the left premotor and superior temporal areas in response to action-related, but not non-action-related, stimuli. However, few studies have investigated the mirror system by using event-related potentials (ERPs) and employing more than one sensory modality in the same sample. In the present study, we compared ERPs that occurred in response to visual and auditory action/non-action-related stimuli to search for evidence of overlapping activations for the two modalities. The results confirmed previous studies that investigated auditory MNS and extended these studies by showing that similar activity existed for the visual modality. Furthermore, we confirmed that the responses to action- and non-action-related stimuli were distinct by demonstrating that, in the case of action-related stimuli, activity was restricted mainly to the left hemisphere, whereas for non-action-related stimuli, activity tended to be more bilateral. The time course of ERP brain sources showed a clear sequence of events that subtended the processing of action-related stimuli. This activity seemed to occur in the left temporal lobe and, in agreement with findings from previous studies of the mirror-neuron network, the information involved appeared to be conveyed subsequently to the premotor area. The left temporo-parietal activity observed following a delay might reflect processing associated with stimulus-related motor preparation. © 2010 The Authors. European Journal of Neuroscience © 2010 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  2. Neural coding of cooperative vs. affective human interactions: 150 ms to code the action's purpose.

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    Alice Mado Proverbio

    Full Text Available The timing and neural processing of the understanding of social interactions was investigated by presenting scenes in which 2 people performed cooperative or affective actions. While the role of the human mirror neuron system (MNS in understanding actions and intentions is widely accepted, little is known about the time course within which these aspects of visual information are automatically extracted. Event-Related Potentials were recorded in 35 university students perceiving 260 pictures of cooperative (e.g., 2 people dragging a box or affective (e.g., 2 people smiling and holding hands interactions. The action's goal was automatically discriminated at about 150-170 ms, as reflected by occipito/temporal N170 response. The swLORETA inverse solution revealed the strongest sources in the right posterior cingulate cortex (CC for affective actions and in the right pSTS for cooperative actions. It was found a right hemispheric asymmetry that involved the fusiform gyrus (BA37, the posterior CC, and the medial frontal gyrus (BA10/11 for the processing of affective interactions, particularly in the 155-175 ms time window. In a later time window (200-250 ms the processing of cooperative interactions activated the left post-central gyrus (BA3, the left parahippocampal gyrus, the left superior frontal gyrus (BA10, as well as the right premotor cortex (BA6. Women showed a greater response discriminative of the action's goal compared to men at P300 and anterior negativity level (220-500 ms. These findings might be related to a greater responsiveness of the female vs. male MNS. In addition, the discriminative effect was bilateral in women and was smaller and left-sided in men. Evidence was provided that perceptually similar social interactions are discriminated on the basis of the agents' intentions quite early in neural processing, differentially activating regions devoted to face/body/action coding, the limbic system and the MNS.

  3. Applauding with closed hands: neural signature of action-sentence compatibility effects.

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    Pia Aravena

    Full Text Available BACKGROUND: Behavioral studies have provided evidence for an action-sentence compatibility effect (ACE that suggests a coupling of motor mechanisms and action-sentence comprehension. When both processes are concurrent, the action sentence primes the actual movement, and simultaneously, the action affects comprehension. The aim of the present study was to investigate brain markers of bidirectional impact of language comprehension and motor processes. METHODOLOGY/PRINCIPAL FINDINGS: Participants listened to sentences describing an action that involved an open hand, a closed hand, or no manual action. Each participant was asked to press a button to indicate his/her understanding of the sentence. Each participant was assigned a hand-shape, either closed or open, which had to be used to activate the button. There were two groups (depending on the assigned hand-shape and three categories (compatible, incompatible and neutral defined according to the compatibility between the response and the sentence. ACEs were found in both groups. Brain markers of semantic processing exhibited an N400-like component around the Cz electrode position. This component distinguishes between compatible and incompatible, with a greater negative deflection for incompatible. Motor response elicited a motor potential (MP and a re-afferent potential (RAP, which are both enhanced in the compatible condition. CONCLUSIONS/SIGNIFICANCE: The present findings provide the first ACE cortical measurements of semantic processing and the motor response. N400-like effects suggest that incompatibility with motor processes interferes in sentence comprehension in a semantic fashion. Modulation of motor potentials (MP and RAP revealed a multimodal semantic facilitation of the motor response. Both results provide neural evidence of an action-sentence bidirectional relationship. Our results suggest that ACE is not an epiphenomenal post-sentence comprehension process. In contrast, motor

  4. Grasping actions and social interaction: neural bases and anatomical circuitry in the monkey

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    Rozzi, Stefano; Coudé, Gino

    2015-01-01

    The study of the neural mechanisms underlying grasping actions showed that cognitive functions are deeply embedded in motor organization. In the first part of this review, we describe the anatomical structure of the motor cortex in the monkey and the cortical and sub-cortical connections of the different motor areas. In the second part, we review the neurophysiological literature showing that motor neurons are not only involved in movement execution, but also in the transformation of object physical features into motor programs appropriate to grasp them (through visuo-motor transformations). We also discuss evidence indicating that motor neurons can encode the goal of motor acts and the intention behind action execution. Then, we describe one of the mechanisms—the mirror mechanism—considered to be at the basis of action understanding and intention reading, and describe the anatomo-functional pathways through which information about the social context can reach the areas containing mirror neurons. Finally, we briefly show that a clear similarity exists between monkey and human in the organization of the motor and mirror systems. Based on monkey and human literature, we conclude that the mirror mechanism relies on a more extended network than previously thought, and possibly subserves basic social functions. We propose that this mechanism is also involved in preparing appropriate complementary response to observed actions, allowing two individuals to become attuned and cooperate in joint actions. PMID:26236258

  5. Grasping actions and social interaction: neural bases and anatomical circuitry in the monkey.

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    Stefano eRozzi

    2015-07-01

    Full Text Available The study of the neural mechanisms underlying grasping actions showed that cognitive functions are deeply embedded in motor organization. In the first part of this review, we describe the anatomical structure of the motor cortex in the monkey and the cortical and sub-cortical connections of the different motor areas. In the second part, we review the neurophysiological literature showing that motor neurons are not only involved in movement execution, but also in the transformation of object physical features into motor programs appropriate to grasp them (through visuo-motor transformations. We also discuss evidence indicating that motor neurons can encode the goal of motor acts and the intention behind action execution. Then, we describe one of the mechanisms – the mirror mechanism – considered to be at the basis of action understanding and intention reading, and describe the anatomo-functional pathways through which information about the social context can reach the areas containing mirror neurons. Finally, we briefly show that a clear similarity exists between monkey and human in the organization of the motor and mirror systems. Based on monkey and human literature, we conclude that the mirror mechanism relies on a more extended network than previously thought, and possibly subserves basic social functions. We propose that this mechanism is also involved in preparing appropriate complementary response to observed actions, allowing two individuals to become attuned and cooperate in joint actions.

  6. Comparable mechanisms for action and language: Neural systems behind intentions, goals and means

    NARCIS (Netherlands)

    Schie, H.T. van; Toni, I.; Bekkering, H.

    2006-01-01

    In this position paper we explore correspondence between neural systems for language and action starting from recent electrophysiological findings on the roles of posterior and frontal areas in goal-directed grasping actions. The paper compares the perceptual and motor organization for action and

  7. Neurophysiology of Grasping Actions: Evidence from ERPs

    Science.gov (United States)

    Koester, Dirk; Schack, Thomas; Westerholz, Jan

    2016-01-01

    We use our hands very frequently to interact with our environment. Neuropsychology together with lesion models and intracranial recordings and imaging work yielded important insights into the functional neuroanatomical correlates of grasping, one important function of our hands, pointing toward a functional parietofrontal brain network. Event-related potentials (ERPs) register directly electrical brain activity and are endowed with high temporal resolution but have long been assumed to be susceptible to movement artifacts. Recent work has shown that reliable ERPs can be obtained during movement execution. Here, we review the available ERP work on (uni) manual grasping actions. We discuss various ERP components and how they may be related to functional components of grasping according to traditional distinctions of manual actions such as planning and control phases. The ERP results are largely in line with the assumption of a parietofrontal network. But other questions remain, in particular regarding the temporal succession of frontal and parietal ERP effects. With the low number of ERP studies on grasping, not all ERP effects appear to be coherent with one another. Understanding the control of our hands may help to develop further neurocognitive theories of grasping and to make progress in prosthetics, rehabilitation or development of technical systems for support of human actions. PMID:28066310

  8. Neural mechanisms of mindfulness and meditation: Evidence from neuroimaging studies

    Institute of Scientific and Technical Information of China (English)

    William; R; Marchand

    2014-01-01

    Mindfulness is the dispassionate,moment-by-moment awareness of sensations,emotions and thoughts.Mindfulness-based interventions are being increasingly used for stress,psychological well being,coping with chronic illness as well as adjunctive treatments for psychiatric disorders.However,the neural mechanisms associated with mindfulness have not been well characterized.Recent functional and structural neuroimaging studies are beginning to provide insights into neural processes associated with the practice of mindfulness.A review of this literature revealed compelling evidence that mindfulness impacts the function of the medial cortex and associated default mode network as well as insula and amygdala.Additionally,mindfulness practice appears to effect lateral frontal regions and basal ganglia,at least in some cases.Structural imaging studies are consistent with these findings and also indicate changes in the hippocampus.While many questions remain unanswered,the current literature provides evidence of brain regions and networks relevant for understanding neural processes associated with mindfulness.

  9. Neural networks for harmonic structure in music perception and action

    OpenAIRE

    Bianco, R.; Novembre, G.; Keller, P. E.; Kim, S G; Scharf, F; Friederici, A.D.; Villringer, A; Sammler, D.

    2016-01-01

    The ability to predict upcoming structured events based on long-term knowledge and contextual priors is a fundamental principle of human cognition. Tonal music triggers predictive processes based on structural properties of harmony, i.e., regularities defining the arrangement of chords into well-formed musical sequences. While the neural architecture of structure-based predictions during music perception is well described, little is known about the neural networks for analogous predictions in...

  10. Neural associative memories for the integration of language, vision and action in an autonomous agent.

    Science.gov (United States)

    Markert, H; Kaufmann, U; Kara Kayikci, Z; Palm, G

    2009-03-01

    Language understanding is a long-standing problem in computer science. However, the human brain is capable of processing complex languages with seemingly no difficulties. This paper shows a model for language understanding using biologically plausible neural networks composed of associative memories. The model is able to deal with ambiguities on the single word and grammatical level. The language system is embedded into a robot in order to demonstrate the correct semantical understanding of the input sentences by letting the robot perform corresponding actions. For that purpose, a simple neural action planning system has been combined with neural networks for visual object recognition and visual attention control mechanisms.

  11. Symmetry Detection in Visual Impairment: Behavioral Evidence and Neural Correlates

    Directory of Open Access Journals (Sweden)

    Zaira Cattaneo

    2014-05-01

    Full Text Available Bilateral symmetry is an extremely salient feature for the human visual system. An interesting issue is whether the perceptual salience of symmetry is rooted in normal visual development. In this review, we discuss empirical work on visual and tactile symmetry detection in normally sighted and visually impaired individuals. On the one hand, available evidence suggests that efficient visual symmetry detection may need normal binocular vision development. On the other hand, converging evidence suggests that symmetry can develop as a principle of haptic perceptual organization in individuals lacking visual experience. Certain features of visual symmetry detection, however, such as the higher salience of the patterns containing a vertical axis of symmetry, do not systematically apply to the haptic modality. The neural correlates (revealed with neuroimaging associated with visual and haptic symmetry detection are also discussed.

  12. Neural and temporal dynamics underlying visual selection for action

    NARCIS (Netherlands)

    Elk, M. van; Schie, H.T. van; Neggers, S.F.W.; Bekkering, H.

    2010-01-01

    The present study investigated the selection for action hypothesis, according to which a subject's action intention to perform a movement influences the way in which visual information is being processed. Subjects were instructed in separate blocks either to grasp or to point to a three-dimensional

  13. Neural Mechanisms Underlying Action Observation in Adults with Down Syndrome

    Science.gov (United States)

    Virji-Babul, Naznin; Moiseev, Alexander; Cheung, Teresa; Weeks, Daniel J.; Cheyne, Douglas; Ribary, Urs

    2010-01-01

    Results of a magnetoencephalography (MEG) brain imaging study conducted to examine the cortical responses during action execution and action observation in 10 healthy adults and 8 age-matched adults with Down syndrome are reported. During execution, the motor responses were strongly lateralized on the ipsilateral rather than the contralateral side…

  14. Neural Mechanisms Underlying Action Observation in Adults with Down Syndrome

    Science.gov (United States)

    Virji-Babul, Naznin; Moiseev, Alexander; Cheung, Teresa; Weeks, Daniel J.; Cheyne, Douglas; Ribary, Urs

    2010-01-01

    Results of a magnetoencephalography (MEG) brain imaging study conducted to examine the cortical responses during action execution and action observation in 10 healthy adults and 8 age-matched adults with Down syndrome are reported. During execution, the motor responses were strongly lateralized on the ipsilateral rather than the contralateral side…

  15. Intention, emotion, and action: a neural theory based on semantic pointers.

    Science.gov (United States)

    Schröder, Tobias; Stewart, Terrence C; Thagard, Paul

    2014-06-01

    We propose a unified theory of intentions as neural processes that integrate representations of states of affairs, actions, and emotional evaluation. We show how this theory provides answers to philosophical questions about the concept of intention, psychological questions about human behavior, computational questions about the relations between belief and action, and neuroscientific questions about how the brain produces actions. Our theory of intention ties together biologically plausible mechanisms for belief, planning, and motor control. The computational feasibility of these mechanisms is shown by a model that simulates psychologically important cases of intention. © 2013 Cognitive Science Society, Inc.

  16. Action mechanisms for social cognition: behavioral and neural correlates of developing Theory of Mind.

    Science.gov (United States)

    Bowman, Lindsay C; Thorpe, Samuel G; Cannon, Erin N; Fox, Nathan A

    2016-08-29

    Many psychological theories posit foundational links between two fundamental constructs: (1) our ability to produce, perceive, and represent action; and (2) our ability to understand the meaning and motivation behind the action (i.e. Theory of Mind; ToM). This position is contentious, however, and long-standing competing theories of social-cognitive development debate roles for basic action-processing in ToM. Developmental research is key to investigating these hypotheses, but whether individual differences in neural and behavioral measures of motor action relate to social-cognitive development is unknown. We examined 3- to 5-year-old children's (N = 26) EEG mu-desynchronization during production of object-directed action, and explored associations between mu-desynchronization and children's behavioral motor skills, behavioral action-representation abilities, and behavioral ToM. For children with high (but not low) mu-desynchronization, motor skill related to action-representation abilities, and action-representation mediated relations between motor skill and ToM. Results demonstrate novel foundational links between action-processing and ToM, suggesting that basic motor action may be a key mechanism for social-cognitive development, thus shedding light on the origins and emergence of higher social cognition.

  17. Action prediction in younger versus older adults: neural correlates of motor familiarity.

    Directory of Open Access Journals (Sweden)

    Nadine Diersch

    Full Text Available Generating predictions during action observation is essential for efficient navigation through our social environment. With age, the sensitivity in action prediction declines. In younger adults, the action observation network (AON, consisting of premotor, parietal and occipitotemporal cortices, has been implicated in transforming executed and observed actions into a common code. Much less is known about age-related changes in the neural representation of observed actions. Using fMRI, the present study measured brain activity in younger and older adults during the prediction of temporarily occluded actions (figure skating elements and simple movement exercises. All participants were highly familiar with the movement exercises whereas only some participants were experienced figure skaters. With respect to the AON, the results confirm that this network was preferentially engaged for the more familiar movement exercises. Compared to younger adults, older adults recruited visual regions to perform the task and, additionally, the hippocampus and caudate when the observed actions were familiar to them. Thus, instead of effectively exploiting the sensorimotor matching properties of the AON, older adults seemed to rely predominantly on the visual dynamics of the observed actions to perform the task. Our data further suggest that the caudate played an important role during the prediction of the less familiar figure skating elements in better-performing groups. Together, these findings show that action prediction engages a distributed network in the brain, which is modulated by the content of the observed actions and the age and experience of the observer.

  18. Action mechanisms for social cognition: behavioral and neural correlates of developing Theory of Mind

    Science.gov (United States)

    Bowman, Lindsay C.; Thorpe, Samuel G.; Cannon, Erin N.; Fox, Nathan A.

    2016-01-01

    Many psychological theories posit foundational links between two fundamental constructs: (1) our ability to produce, perceive, and represent action; and (2) our ability to understand the meaning and motivation behind the action (i.e. Theory of Mind; ToM). This position is contentious, however, and long-standing competing theories of social-cognitive development debate roles for basic action-processing in ToM. Developmental research is key to investigating these hypotheses, but whether individual differences in neural and behavioral measures of motor action relate to social-cognitive development is unknown. We examined 3- to 5-year-old children’s (N = 26) EEG mu-desynchronization during production of object-directed action, and explored associations between mu-desynchronization and children’s behavioral motor skills, behavioral action-representation abilities, and behavioral ToM. For children with high (but not low) mu-desynchronization, motor skill related to action-representation abilities, and action-representation mediated relations between motor skill and ToM. Results demonstrate novel foundational links between action-processing and ToM, suggesting that basic motor action may be a key mechanism for social-cognitive development, thus shedding light on the origins and emergence of higher social cognition. PMID:27573916

  19. Attribution of intentional causation influences the perception of observed movements: Behavioural evidence and neural correlates

    Directory of Open Access Journals (Sweden)

    James W Moore

    2013-01-01

    Full Text Available Recent research on human agency suggests that intentional causation is associated with a subjective compression in the temporal interval between actions and their effects. That is, intentional movements and their causal effects are perceived as closer together in time than equivalent unintentional movements and their causal effects. This so-called intentional binding effect is consistently found for one’s own self-generated actions. It has also been suggested that intentional binding occurs when observing intentional movements of others. However, this evidence is undermined by limitations of the paradigm used. In the current study we aimed to overcome these limitations using a more rigorous design in combination with functional Magnetic Resonance Imaging (fMRI to explore the neural underpinnings of intentional binding of observed movements. In particular, we aimed to identify brain areas sensitive to the interaction between intentionality and causality attributed to the observed action. Our behavioural results confirmed the occurrence of intentional binding for observed movements using this more rigorous paradigm. Our fMRI results highlighted a collection of brain regions whose activity was sensitive to the interaction between intentionality and causation. Intriguingly, these brain regions have previously been implicated in the sense of agency over one’s own movements. We discuss the implications of these results for intentional binding specifically, and the sense of agency more generally.

  20. Dissociating modality-specific and supramodal neural systems for action understanding.

    Science.gov (United States)

    Spunt, Robert P; Lieberman, Matthew D

    2012-03-01

    The neural basis of action understanding in humans remains disputed, with some research implicating the putative mirror neuron system (MNS) and some a mentalizing system (MZS) for inferring mental states. The basis for this dispute may be that action understanding is a heterogeneous construct: actions can be understood from sensory information about body movements or from language about action, and with the goal of understanding the implementation ("how") or motive ("why") of an action. Although extant research implicates the MNS in understanding implementation and the MZS in understanding motive, it remains unknown to what extent these systems subserve modality-specific or supramodal functions in action understanding. While undergoing fMRI, 21 volunteers considered the implementation ("How is she doing it?") and motive ("Why is she doing it?") for actions presented in video or text. Bilateral parietal and right frontal areas of the MNS showed a modality-specific association with perceiving actions in videos, while left-hemisphere MNS showed a supramodal association with understanding implementation. Largely left-hemisphere MZS showed a supramodal association with understanding motive; however, connectivity among the MZS and MNS during the inference of motive was modality specific, being significantly stronger when motive was understood from actions in videos compared to text. These results support a tripartite model of MNS and MZS contributions to action understanding, where distinct areas of the MNS contribute to action perception ("perceiving what") and the representation of action implementation ("knowing how"), while the MZS supports an abstract, modality-independent representation of the mental states that explain action performance ("knowing why").

  1. Deep Manifold Learning Combined With Convolutional Neural Networks for Action Recognition.

    Science.gov (United States)

    Chen, Xin; Weng, Jian; Lu, Wei; Xu, Jiaming; Weng, Jiasi

    2017-09-15

    Learning deep representations have been applied in action recognition widely. However, there have been a few investigations on how to utilize the structural manifold information among different action videos to enhance the recognition accuracy and efficiency. In this paper, we propose to incorporate the manifold of training samples into deep learning, which is defined as deep manifold learning (DML). The proposed DML framework can be adapted to most existing deep networks to learn more discriminative features for action recognition. When applied to a convolutional neural network, DML embeds the previous convolutional layer's manifold into the next convolutional layer; thus, the discriminative capacity of the next layer can be promoted. We also apply the DML on a restricted Boltzmann machine, which can alleviate the overfitting problem. Experimental results on four standard action databases (i.e., UCF101, HMDB51, KTH, and UCF sports) show that the proposed method outperforms the state-of-the-art methods.

  2. Self-Organizing Neural Integration of Pose-Motion Features for Human Action Recognition

    Directory of Open Access Journals (Sweden)

    German Ignacio Parisi

    2015-06-01

    Full Text Available The visual recognition of complex, articulated human movements is fundamental for a wide range of artificial systems oriented towards human-robot communication, action classification, and action-driven perception. These challenging tasks may generally involve the processing of a huge amount of visual information and learning-based mechanisms for generalizing a set of training actions and classifying new samples. To operate in natural environments, a crucial property is the efficient and robust recognition of actions, also under noisy conditions caused by, for instance, systematic sensor errors and temporarily occluded persons. Studies of the mammalian visual system and its outperforming ability to process biological motion information suggest separate neural pathways for the distinct processing of pose and motion features at multiple levels and the subsequent integration of these visual cues for action perception. We present a neurobiologically-motivated approach to achieve noise-tolerant action recognition in real time. Our model consists of self-organizing Growing When Required (GWR networks that obtain progressively generalized representations of sensory inputs and learn inherent spatiotemporal dependencies. During the training, the GWR networks dynamically change their topological structure to better match the input space. We first extract pose and motion features from video sequences and then cluster actions in terms of prototypical pose-motion trajectories. Multi-cue trajectories from matching action frames are subsequently combined to provide action dynamics in the joint feature space. Reported experiments show that our approach outperforms previous results on a dataset of full-body actions captured with a depth sensor, and ranks among the best 21 results for a public benchmark of domestic daily actions.

  3. Self-organizing neural integration of pose-motion features for human action recognition.

    Science.gov (United States)

    Parisi, German I; Weber, Cornelius; Wermter, Stefan

    2015-01-01

    The visual recognition of complex, articulated human movements is fundamental for a wide range of artificial systems oriented toward human-robot communication, action classification, and action-driven perception. These challenging tasks may generally involve the processing of a huge amount of visual information and learning-based mechanisms for generalizing a set of training actions and classifying new samples. To operate in natural environments, a crucial property is the efficient and robust recognition of actions, also under noisy conditions caused by, for instance, systematic sensor errors and temporarily occluded persons. Studies of the mammalian visual system and its outperforming ability to process biological motion information suggest separate neural pathways for the distinct processing of pose and motion features at multiple levels and the subsequent integration of these visual cues for action perception. We present a neurobiologically-motivated approach to achieve noise-tolerant action recognition in real time. Our model consists of self-organizing Growing When Required (GWR) networks that obtain progressively generalized representations of sensory inputs and learn inherent spatio-temporal dependencies. During the training, the GWR networks dynamically change their topological structure to better match the input space. We first extract pose and motion features from video sequences and then cluster actions in terms of prototypical pose-motion trajectories. Multi-cue trajectories from matching action frames are subsequently combined to provide action dynamics in the joint feature space. Reported experiments show that our approach outperforms previous results on a dataset of full-body actions captured with a depth sensor, and ranks among the best results for a public benchmark of domestic daily actions.

  4. Assistive Technology in Australia: Integrating theory and evidence into action.

    Science.gov (United States)

    Steel, Emily J; Layton, Natasha A

    2016-12-01

    Occupational therapists use a range of strategies to influence the relationship between person, environment and occupation and facilitate people's participation and inclusion in society. Technology is a fundamental environmental factor capable of enabling inclusion, and occupational therapy models articulate a role for assistive technology (AT) devices and services, but there is a gap between theory, research and practice. The context of AT provision in Australia presents systemic barriers that prevent optimal application of AT devices and services for societal health promotion and in individualised solutions. The Integrating Theory, Evidence and Action method (ITEA) was used to answer the question 'How can occupational therapy support AT provision to enable older people and people with disability?' A wide range of sources were systematically analysed to explore the complexities of AT provision in Australia. The International Classification of Functioning, Disability and Health (ICF) and IMPACT(2) model are used as frameworks to reconstruct evidence into statements that summarise the theory, process and outcomes of AT provision. Analysis of the influence of the global disability rights and local policies and AT provision systems is used to highlight important aspects for occupational therapists to consider in research and practice. Pragmatic recommendations are provided to enable practitioners to translate theory and evidence into action. AT provision can be improved by focusing on evidence for and congruence between theory, process and outcomes, rather than isolated interventions. Occupational therapists should consider the influence of contextual factors on practice, and work with consumers to improve access and equity in AT provision systems. © 2016 Occupational Therapy Australia.

  5. Acetaminophen reduces social pain: behavioral and neural evidence.

    Science.gov (United States)

    Dewall, C Nathan; Macdonald, Geoff; Webster, Gregory D; Masten, Carrie L; Baumeister, Roy F; Powell, Caitlin; Combs, David; Schurtz, David R; Stillman, Tyler F; Tice, Dianne M; Eisenberger, Naomi I

    2010-07-01

    Pain, whether caused by physical injury or social rejection, is an inevitable part of life. These two types of pain-physical and social-may rely on some of the same behavioral and neural mechanisms that register pain-related affect. To the extent that these pain processes overlap, acetaminophen, a physical pain suppressant that acts through central (rather than peripheral) neural mechanisms, may also reduce behavioral and neural responses to social rejection. In two experiments, participants took acetaminophen or placebo daily for 3 weeks. Doses of acetaminophen reduced reports of social pain on a daily basis (Experiment 1). We used functional magnetic resonance imaging to measure participants' brain activity (Experiment 2), and found that acetaminophen reduced neural responses to social rejection in brain regions previously associated with distress caused by social pain and the affective component of physical pain (dorsal anterior cingulate cortex, anterior insula). Thus, acetaminophen reduces behavioral and neural responses associated with the pain of social rejection, demonstrating substantial overlap between social and physical pain.

  6. An integrative neural model of social perception, action observation, and theory of mind.

    Science.gov (United States)

    Yang, Daniel Y-J; Rosenblau, Gabriela; Keifer, Cara; Pelphrey, Kevin A

    2015-04-01

    In the field of social neuroscience, major branches of research have been instrumental in describing independent components of typical and aberrant social information processing, but the field as a whole lacks a comprehensive model that integrates different branches. We review existing research related to the neural basis of three key neural systems underlying social information processing: social perception, action observation, and theory of mind. We propose an integrative model that unites these three processes and highlights the posterior superior temporal sulcus (pSTS), which plays a central role in all three systems. Furthermore, we integrate these neural systems with the dual system account of implicit and explicit social information processing. Large-scale meta-analyses based on Neurosynth confirmed that the pSTS is at the intersection of the three neural systems. Resting-state functional connectivity analysis with 1000 subjects confirmed that the pSTS is connected to all other regions in these systems. The findings presented in this review are specifically relevant for psychiatric research especially disorders characterized by social deficits such as autism spectrum disorder.

  7. An integrative neural model of social perception, action observation, and theory of mind

    Science.gov (United States)

    Yang, Daniel Y.-J.; Rosenblau, Gabriela; Keifer, Cara; Pelphrey, Kevin A.

    2016-01-01

    In the field of social neuroscience, major branches of research have been instrumental in describing independent components of typical and aberrant social information processing, but the field as a whole lacks a comprehensive model that integrates different branches. We review existing research related to the neural basis of three key neural systems underlying social information processing: social perception, action observation, and theory of mind. We propose an integrative model that unites these three processes and highlights the posterior superior temporal sulcus (pSTS), which plays a central role in all three systems. Furthermore, we integrate these neural systems with the dual system account of implicit and explicit social information processing. Large-scale meta-analyses based on Neurosynth confirmed that the pSTS is at the intersection of the three neural systems. Resting-state functional connectivity analysis with 1000 subjects confirmed that the pSTS is connected to all other regions in these systems. The findings presented in this review are specifically relevant for psychiatric research especially disorders characterized by social deficits such as autism spectrum disorder. PMID:25660957

  8. Neural network development in late adolescents during observation of risk-taking action.

    Directory of Open Access Journals (Sweden)

    Miyuki Tamura

    Full Text Available Emotional maturity and social awareness are important for adolescents, particularly college students beginning to face the challenges and risks of the adult world. However, there has been relatively little research into personality maturation and psychological development during late adolescence and the neural changes underlying this development. We investigated the correlation between psychological properties (neuroticism, extraversion, anxiety, and depression and age among late adolescents (n = 25, from 18 years and 1 month to 22 years and 8 months. The results revealed that late adolescents became less neurotic, less anxious, less depressive and more extraverted as they aged. Participants then observed video clips depicting hand movements with and without a risk of harm (risk-taking or safe actions during functional magnetic resonance imaging (fMRI. The results revealed that risk-taking actions elicited significantly stronger activation in the bilateral inferior parietal lobule, temporal visual regions (superior/middle temporal areas, and parieto-occipital visual areas (cuneus, middle occipital gyri, precuneus. We found positive correlations of age and extraversion with neural activation in the insula, middle temporal gyrus, lingual gyrus, and precuneus. We also found a negative correlation of age and anxiety with activation in the angular gyrus, precentral gyrus, and red nucleus/substantia nigra. Moreover, we found that insula activation mediated the relationship between age and extraversion. Overall, our results indicate that late adolescents become less anxious and more extraverted with age, a process involving functional neural changes in brain networks related to social cognition and emotional processing. The possible neural mechanisms of psychological and social maturation during late adolescence are discussed.

  9. Pattern recognition in field crickets: concepts and neural evidence.

    Science.gov (United States)

    Kostarakos, Konstantinos; Hedwig, Berthold

    2015-01-01

    Since decades the acoustic communication behavior of crickets is in the focus of neurobiology aiming to analyze the neural basis of male singing and female phonotactic behavior. For temporal pattern recognition several different concepts have been proposed to elucidate the possible neural mechanisms underlying the tuning of phonotaxis in females. These concepts encompass either some form of a feature detecting mechanism using cross-correlation processing, temporal filter properties of brain neurons or an autocorrelation processing based on a delay-line and coincidence detection mechanism. Current data based on intracellular recordings of auditory brain neurons indicate a sequential processing by excitation and inhibition in a local auditory network within the protocerebrum. The response properties of the brain neurons point towards the concept of an autocorrelation-like mechanism underlying female pattern recognition in which delay-lines by long lasting inhibition may be involved.

  10. Using accelerometers for physical actions recognition by a neural fuzzy network.

    Science.gov (United States)

    Liu, Shing-Hong; Chang, Yuan-Jen

    2009-11-01

    Triaxial accelerometers were employed to monitor human actions under various conditions. This study aimed to determine an optimum classification scheme and sensor placement positions for recognizing different types of physical action. Three triaxial accelerometers were placed on the chest, waist, and thigh, and their abilities to recognize the three actions of walking, sitting down, and falling were determined. The features of the resultant triaxial signals from each accelerometer were extracted by an autoregression (AR) model. A self-constructing neural fuzzy inference network (SONFIN) was used to recognize the three actions. The performance of the SONFIN was assessed based on statistical parameters, sensitivity, specificity, and total classification accuracy. The results show that the SONFIN provided a stability total classification accuracy of 96.3% and 88.7% for the training and testing data, when the parameters of the 60-order AR model were used as the input feature vector, and the accelerometer was placed anywhere on the abdomen. Seven elderly individuals performing the three basic actions had 80.4% confirmation for the testing data.

  11. Mental training enhances attentional stability: neural and behavioral evidence.

    Science.gov (United States)

    Lutz, Antoine; Slagter, Heleen A; Rawlings, Nancy B; Francis, Andrew D; Greischar, Lawrence L; Davidson, Richard J

    2009-10-21

    The capacity to stabilize the content of attention over time varies among individuals, and its impairment is a hallmark of several mental illnesses. Impairments in sustained attention in patients with attention disorders have been associated with increased trial-to-trial variability in reaction time and event-related potential deficits during attention tasks. At present, it is unclear whether the ability to sustain attention and its underlying brain circuitry are transformable through training. Here, we show, with dichotic listening task performance and electroencephalography, that training attention, as cultivated by meditation, can improve the ability to sustain attention. Three months of intensive meditation training reduced variability in attentional processing of target tones, as indicated by both enhanced theta-band phase consistency of oscillatory neural responses over anterior brain areas and reduced reaction time variability. Furthermore, those individuals who showed the greatest increase in neural response consistency showed the largest decrease in behavioral response variability. Notably, we also observed reduced variability in neural processing, in particular in low-frequency bands, regardless of whether the deviant tone was attended or unattended. Focused attention meditation may thus affect both distracter and target processing, perhaps by enhancing entrainment of neuronal oscillations to sensory input rhythms, a mechanism important for controlling the content of attention. These novel findings highlight the mechanisms underlying focused attention meditation and support the notion that mental training can significantly affect attention and brain function.

  12. Insulin-like growth factor actions during development of neural stem cells and progenitors in the central nervous system.

    Science.gov (United States)

    Ye, Ping; D'Ercole, A Joseph

    2006-01-01

    Insulin-like growth factor-I (IGF-I) plays a key role in normal development. Recent studies show that IGF-I exerts a wide variety actions in the central nervous system during development as well as in adulthood. This report reviews recent developments on IGF-I actions and its mechanisms in the central nervous system, with a focus on its actions during the development of neural stem cells and progenitors. Available data strongly indicate that IGF-I shortens the length of the cell cycle in neuron progenitors during embryonic life and has an influence on the growth of all neural cell types. The phosphatidylinositol-3 kinase/Akt and mitogen-activated protein kinase pathways seem to be the predominant mediators of IGF-I-stimulated neural cell proliferation and survival. IGF-I actions, however, likely depend on cell type, developmental stage, and microenvironmental milieu.

  13. Evidence for the Automatic Evaluation of Self-Generated Actions

    Science.gov (United States)

    Aarts, Kristien; De Houwer, Jan; Pourtois, Gilles

    2012-01-01

    The accuracy of simple actions is swiftly determined through specific monitoring brain systems. However, it remains unclear whether this evaluation is accompanied by a rapid and compatible emotional appraisal of the action that allows to mark incorrect actions as negative/bad and conversely correct actions as positive/good. In this study, we used…

  14. Wavelet transform for real-time detection of action potentials in neural signals.

    Science.gov (United States)

    Quotb, Adam; Bornat, Yannick; Renaud, Sylvie

    2011-01-01

    We present a study on wavelet detection methods of neuronal action potentials (APs). Our final goal is to implement the selected algorithms on custom integrated electronics for on-line processing of neural signals; therefore we take real-time computing as a hard specification and silicon area as a price to pay. Using simulated neural signals including APs, we characterize an efficient wavelet method for AP extraction by evaluating its detection rate and its implementation cost. We compare software implementation for three methods: adaptive threshold, discrete wavelet transform (DWT), and stationary wavelet transform (SWT). We evaluate detection rate and implementation cost for detection functions dynamically comparing a signal with an adaptive threshold proportional to its SD, where the signal is the raw neural signal, respectively: (i) non-processed; (ii) processed by a DWT; (iii) processed by a SWT. We also use different mother wavelets and test different data formats to set an optimal compromise between accuracy and silicon cost. Detection accuracy is evaluated together with false negative and false positive detections. Simulation results show that for on-line AP detection implemented on a configurable digital integrated circuit, APs underneath the noise level can be detected using SWT with a well-selected mother wavelet, combined to an adaptive threshold.

  15. Experimental evidence of a chaotic region in a neural pacemaker

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Hua-Guang, E-mail: guhuaguang@tongji.edu.cn [School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092 (China); Department of Electronic Engineering, City University of Hong Kong, Hong Kong SAR (China); Jia, Bing [School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092 (China); Chen, Guan-Rong [Department of Electronic Engineering, City University of Hong Kong, Hong Kong SAR (China)

    2013-03-15

    In this Letter, we report the finding of period-adding scenarios with chaos in firing patterns, observed in biological experiments on a neural pacemaker, with fixed extra-cellular potassium concentration at different levels and taken extra-cellular calcium concentration as the bifurcation parameter. The experimental bifurcations in the two-dimensional parameter space demonstrate the existence of a chaotic region interwoven with the periodic region thereby forming a period-adding sequence with chaos. The behavior of the pacemaker in this region is qualitatively similar to that of the Hindmarsh–Rose neuron model in a well-known comb-shaped chaotic region in two-dimensional parameter spaces.

  16. Consequences of converting graded to action potentials upon neural information coding and energy efficiency.

    Science.gov (United States)

    Sengupta, Biswa; Laughlin, Simon Barry; Niven, Jeremy Edward

    2014-01-01

    Information is encoded in neural circuits using both graded and action potentials, converting between them within single neurons and successive processing layers. This conversion is accompanied by information loss and a drop in energy efficiency. We investigate the biophysical causes of this loss of information and efficiency by comparing spiking neuron models, containing stochastic voltage-gated Na(+) and K(+) channels, with generator potential and graded potential models lacking voltage-gated Na(+) channels. We identify three causes of information loss in the generator potential that are the by-product of action potential generation: (1) the voltage-gated Na(+) channels necessary for action potential generation increase intrinsic noise and (2) introduce non-linearities, and (3) the finite duration of the action potential creates a 'footprint' in the generator potential that obscures incoming signals. These three processes reduce information rates by ∼50% in generator potentials, to ∼3 times that of spike trains. Both generator potentials and graded potentials consume almost an order of magnitude less energy per second than spike trains. Because of the lower information rates of generator potentials they are substantially less energy efficient than graded potentials. However, both are an order of magnitude more efficient than spike trains due to the higher energy costs and low information content of spikes, emphasizing that there is a two-fold cost of converting analogue to digital; information loss and cost inflation.

  17. The role of expectation in multisensory body representation - neural evidence.

    Science.gov (United States)

    Ferri, Francesca; Ambrosini, Ettore; Pinti, Paola; Merla, Arcangelo; Costantini, Marcello

    2017-08-01

    Sensory events contribute to body ownership, the feeling that the body belongs to me. However, the encoding of sensory events is not only reactive, but also proactive in that our brain generates prediction about forthcoming stimuli. In previous studies, we have shown that prediction of sensory events is a sufficient condition to induce the sense of body ownership. In this study, we investigated the underlying neural mechanisms. Participants were seated with their right arm resting upon a table just below another smaller table. Hence, the real hand was hidden from the participant's view and a life-sized rubber model of a right hand was placed on the small table in front of them. Participants observed a wooden plank while approaching - without touching - the rubber hand. We measured the phenomenology of the illusion by means of questionnaire. Neural activity was recorded by means of near-infrared spectroscopy (fNIRS). Results showed higher activation of multisensory parietal cortices in the rubber hand illusion induced by touch expectation. Furthermore, such activity was correlated with the subjective feeling of owning the rubber hand. Our results enrich current models of body ownership suggesting that our multisensory brain regions generate prediction on what could be my body and what could not. This finding might have interesting implications in all those cases in which body representation is altered, anorexia, bulimia nervosa and obesity, among others. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  18. Neural recording front-end IC using action potential detection and analog buffer with digital delay for data compression.

    Science.gov (United States)

    Liu, Lei; Yao, Lei; Zou, Xiaodan; Goh, Wang Ling; Je, Minkyu

    2013-01-01

    This paper presents a neural recording analog front-end IC intended for simultaneous neural recording with action potential (AP) detection for data compression in wireless multichannel neural implants. The proposed neural recording front-end IC detects the neural spikes and sends only the preserved AP information for wireless transmission in order to reduce the overall power consumption of the neural implant. The IC consists of a low-noise neural amplifier, an AP detection circuit and an analog buffer with digital delay. The neural amplifier makes use of a current-reuse technique to maximize the transconductance efficiency for attaining a good noise efficiency factor. The AP detection circuit uses an adaptive threshold voltage to generate an enable signal for the subsequent functional blocks. The analog buffer with digital delay is employed using a finite impulse response (FIR) filter which preserves the AP waveform before the enable signal as well as provides low-pass filtering. The neural recording front-end IC has been designed using standard CMOS 0.18-µm technology occupying a core area of 220 µm by 820 µm.

  19. Experimental evidence for action imitation in killer whales (Orcinus orca).

    Science.gov (United States)

    Abramson, José Z; Hernández-Lloreda, Victoria; Call, Josep; Colmenares, Fernando

    2013-01-01

    Comparative experimental studies of imitative learning have focused mainly on primates and birds. However, cetaceans are promising candidates to display imitative learning as they have evolved in socioecological settings that have selected for large brains, complex sociality, and coordinated predatory tactics. Here we tested imitative learning in killer whales, Orcinus orca. We used a 'do-as-other-does' paradigm in which 3 subjects witnessed a conspecific demonstrator's performance that included 15 familiar and 4 novel behaviours. The three subjects (1) learned the copy command signal 'Do that' very quickly, that is, 20 trials on average; (2) copied 100 % of the demonstrator's familiar and novel actions; (3) achieved full matches in the first attempt for 8-13 familiar behaviours (out of 15) and for the 2 novel behaviours (out of 2) in one subject; and (4) took no longer than 8 trials to accurately copy any familiar behaviour, and no longer than 16 trials to copy any novel behaviour. This study provides experimental evidence for body imitation, including production imitation, in killer whales that is comparable to that observed in dolphins tested under similar conditions. These findings suggest that imitative learning may underpin some of the group-specific traditions reported in killer whales in the field.

  20. Calcium phosphopeptides -- mechanisms of action and evidence for clinical efficacy.

    Science.gov (United States)

    Cochrane, N J; Reynolds, E C

    2012-09-01

    Phosphoproteins/phosphopeptides with clusters of acidic residues are found throughout nature, where they aid in the prevention of unwanted precipitation of solid calcium phosphates. The acidic residues, particularly phosphoserine, interact with calcium and stabilize clusters of calcium and phosphate. Saliva and milk are two examples of biological fluids that contain such phosphoprotein/phosphopeptide-stabilized calcium phosphates, and both share a similar evolutionary pathway. Saliva has been shown to have remineralization potential and is of critical importance in maintaining the mineral content of teeth in the oral environment. Milk can be enzymatically modified to release casein phosphopeptides that contain the clusters of residues that allow milk to stabilize high concentrations of calcium and phosphate. These casein phosphopeptide-stabilized amorphous calcium phosphate nanocomplexes (CPP-ACP) can stabilize even higher concentrations of calcium and phosphate than milk and can be considered a salivary biomimetic, since they share many similarities to statherin. The mechanisms of action and the growing body of scientific evidence that supports the use of CPP-ACP to augment fluoride in inhibiting demineralization and enhancing the remineralization of white-spot lesions are reviewed.

  1. Neural Substrates of Semantic Prospection – Evidence from the Dementias

    Directory of Open Access Journals (Sweden)

    Muireann eIrish

    2016-05-01

    Full Text Available The ability to envisage personally relevant events at a future time point represents an incredibly sophisticated cognitive endeavor and one that appears to be intimately linked to episodic memory integrity. Far less is known regarding the neurocognitive mechanisms underpinning the capacity to envisage non-personal future occurrences, known as semantic future thinking. Moreover the degree of overlap between the neural substrates supporting episodic and semantic forms of prospection remains unclear. To this end, we sought to investigate the capacity for episodic and semantic future thinking in Alzheimer’s disease (n = 15 and disease-matched behavioral-variant frontotemporal dementia (n = 15, neurodegenerative disorders characterized by significant medial temporal lobe and frontal pathology. Participants completed an assessment of past and future thinking across personal (episodic and non-personal (semantic domains, as part of a larger neuropsychological battery investigating episodic and semantic processing, and their performance was contrasted with 20 age- and education-matched healthy older Controls. Participants underwent whole-brain T1 weighted structural imaging and voxel-based morphometry analysis was conducted to determine the relationship between grey matter integrity and episodic and semantic future thinking. Relative to Controls, both patient groups displayed marked future thinking impairments, extending across episodic and semantic domains. Analyses of covariance revealed that while episodic future thinking deficits could be explained solely in terms of episodic memory proficiency, semantic prospection deficits reflected the interplay between episodic and semantic processing. Distinct neural correlates emerged for each form of future simulation with differential involvement of prefrontal, lateral temporal and medial temporal regions. Notably, the hippocampus was implicated irrespective of future thinking domain, with the suggestion of

  2. Neural Mechanisms of Illusory Motion: Evidence from ERP Study

    Directory of Open Access Journals (Sweden)

    Xu Y. A. N. Yun

    2011-05-01

    Full Text Available ERPs were used to examine the neural correlates of illusory motion, by presenting the Rice Wave illusion (CI, its two variants (WI and NI and a real motion video (RM. Results showed that: Firstly, RM elicited a more negative deflection than CI, NI and WI between 200–350ms. Secondly, between 500–600ms, CI elicited a more positive deflection than NI and WI, and RM elicited a more positive deflection than CI, what's more interesting was the sequential enhancement of brain activity with the corresponding motion strength. We inferred that the former component might reflect the successful encoding of the local motion signals in detectors at the lower stage; while the latter one might be involved in the intensive representations of visual input in real/illusory motion perception, this was the whole motion-signal organization in the later stage of motion perception. Finally, between 1185–1450 ms, a significant positive component was found between illusory/real motion tasks than NI (no motion. Overall, we demonstrated that there was a stronger deflection under the corresponding lager motion strength. These results reflected not only the different temporal patterns between illusory and real motion but also extending to their distinguishing working memory representation and storage.

  3. Evidence for single top quark production using Bayesian neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Kau, Daekwang [Florida State Univ., Tallahassee, FL (United States)

    2007-01-01

    We present results of a search for single top quark production in p$\\bar{p}$ collisions using a dataset of approximately 1 fb-1 collected with the D0 detector. This analysis considers the muon+jets and electron+jets final states and makes use of Bayesian neural networks to separate the expected signals from backgrounds. The observed excess is associated with a p-value of 0.081%, assuming the background-only hypothesis, which corresponds to an excess over background of 3.2 standard deviations for a Gaussian density. The p-value computed using the SM signal cross section of 2.9 pb is 1.6%, corresponding to an expected significance of 2.2 standard deviations. Assuming the observed excess is due to single top production, we measure a single top quark production cross section of σ(p$\\bar{p}$ → tb + X, tqb + X) = 4.4 ± 1.5 pb.

  4. Neural evidence for a multifaceted model of attachment security.

    Science.gov (United States)

    Canterberry, Melanie; Gillath, Omri

    2013-06-01

    The sense of attachment security has been linked with a host of beneficial outcomes related to personal and relational well-being. Moreover, research has demonstrated that the sense of attachment security can be enhanced via cognitive priming techniques. Studies using such techniques have shown that security priming results with similar outcomes as dispositional attachment security. The way security priming leads to these effects, however, is yet to be unveiled. Using fMRI we took one step in that direction and examined the neural mechanisms underlying enhanced attachment security. Participants were exposed to explicit and implicit security- and insecurity-related words. Security priming led to co-occurring activation in brain areas reflective of cognitive, affective, and behavioral processes (e.g., medial frontal cortex, parahippocampus, BA 6). There were activation differences based on attachment style. This research serves as an important step in mapping out the security process and supports a conceptualization of security as part of a behavioral system with multiple components. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Neural Stem Cell Differentiation Is Dictated by Distinct Actions of Nuclear Receptor Corepressors and Histone Deacetylases

    Directory of Open Access Journals (Sweden)

    Gonçalo Castelo-Branco

    2014-09-01

    Full Text Available Signaling factors including retinoic acid (RA and thyroid hormone (T3 promote neuronal, oligodendrocyte, and astrocyte differentiation of cortical neural stem cells (NSCs. However, the functional specificity of transcriptional repressor checkpoints controlling these differentiation programs remains unclear. Here, we show by genome-wide analysis that histone deacetylase (HDAC2 and HDAC3 show overlapping and distinct promoter occupancy at neuronal and oligodendrocyte-related genes in NSCs. The absence of HDAC3, but not HDAC2, initiated a neuronal differentiation pathway in NSCs. The ablation of the corepressor NCOR or HDAC2, in conjunction with T3 treatment, resulted in increased expression of oligodendrocyte genes, revealing a direct HDAC2-mediated repression of Sox8 and Sox10 expression. Interestingly, Sox10 was required also for maintaining the more differentiated state by repression of stem cell programming factors such as Sox2 and Sox9. Distinct and nonredundant actions of NCORs and HDACs are thus critical for control of lineage progression and differentiation programs in neural progenitors.

  6. Serotonin transporter polymorphism modulates neural correlates of real-life joint action. An investigation with functional near-infrared spectroscopy (fNIRS).

    Science.gov (United States)

    Herrmann, M J; Bogon, J; Quester, S; Cordes, A; Stenneken, P; Reif, A; Ehlis, A-C

    2015-04-30

    A functional polymorphism (5-HTTLPR) within the serotonin transporter gene (SERT) has been associated with personality dimensions such as neuroticism, with emotional reactivity to negative events, and with an increased risk of affective disorders. More specifically, the short (S) allele of 5-HTTLPR has been linked to increased amygdala activity and has been identified as a risk allele for depressive disorders. Recently, Homberg and Lesch (2011) urged for a conceptual change in the current deficit-oriented connotation of the 5-HTTLPR S-allele and argued that the S-allele could be considered adaptive in certain contexts. They postulated that S-allele carriers show hypervigilant behavior in social situations and should thus show increased social conformity. Therefore, we tested whether 5-HTTLPR modulates the neural correlates of real-life social joint action through functional near-infrared spectroscopy (fNIRS). Thirty participants, homozygote for 5-HTTLPR, were measured and analyzed while they were involved in a previously published joint-action paradigm, which reliably leads to an activation of the left parietal cortex. We found that homozygote S-allele carriers showed increased inferior parietal lobe activation, compared to the LL-allele carriers for the contrast "joint action greater solo action". Therefore, our results provide evidence for beneficial effects of the S-allele on the neural correlates of social interactions.

  7. Swallowing and Dysphagia Rehabilitation: Translating Principles of Neural Plasticity into Clinically Oriented Evidence

    Science.gov (United States)

    Robbins, JoAnne; Butler, Susan G.; Daniels, Stephanie K.; Gross, Roxann Diez; Langmore, Susan; Lazarus, Cathy L.; Martin-Harris, Bonnie; McCabe, Daniel; Musson, Nan; Rosenbek, John

    2008-01-01

    Purpose: This review presents the state of swallowing rehabilitation science as it relates to evidence for neural plastic changes in the brain. The case is made for essential collaboration between clinical and basic scientists to expand the positive influences of dysphagia rehabilitation in synergy with growth in technology and knowledge. The…

  8. Sentential Negation Might Share Neurophysiological Mechanisms with Action Inhibition. Evidence from Frontal Theta Rhythm.

    Science.gov (United States)

    de Vega, Manuel; Morera, Yurena; León, Inmaculada; Beltrán, David; Casado, Pilar; Martín-Loeches, Manuel

    2016-06-01

    According to the literature, negations such as "not" or "don't" reduce the accessibility in memory of the concepts under their scope. Moreover, negations applied to action contents (e.g., "don't write the letter") impede the activation of motor processes in the brain, inducing "disembodied" representations. These facts provide important information on the behavioral and neural consequences of negations. However, how negations themselves are processed in the brain is still poorly understood. In two electrophysiological experiments, we explored whether sentential negation shares neural mechanisms with action monitoring or inhibition. Human participants read action-related sentences in affirmative or negative form ("now you will cut the bread" vs "now you will not cut the bread") while performing a simultaneous Go/NoGo task. The analysis of the EEG rhythms revealed that theta oscillations were significantly reduced for NoGo trials in the context of negative sentences compared with affirmative sentences. Given the fact that theta oscillations are often considered as neural markers of response inhibition processes, their modulation by negative sentences strongly suggests that negation uses neural resources of response inhibition. We propose a new approach that views the syntactic operator of negation as relying on the neural machinery of high-order action-monitoring processes. Previous studies have shown that linguistic negation reduces the accessibility of the negated concepts and suppresses the activation of specific brain regions that operate in affirmative statements. Although these studies focus on the consequences of negation on cognitive and neural processes, the proper neural mechanisms of negation have not yet been explored. In the present EEG study, we tested the hypothesis that negation uses the neural network of action inhibition. Using a Go/NoGo task embedded in a sentence comprehension task, we found that negation in the context of NoGo trials modulates

  9. A Prospective Longitudinal Study of Perceived Infant Outcomes at 18-24 months: Neural and Psychological Correlates of Parental Thoughts and Actions Assessed during the First Month Postpartum

    Directory of Open Access Journals (Sweden)

    Pilyoung eKim

    2015-11-01

    Full Text Available The first postpartum months constitute a critical period for parents to establish an emotional bond with their infants. Neural responses to infant-related stimuli have been associated with parental sensitivity. However, the associations among these neural responses, parenting, and later infant outcomes for mothers and fathers are unknown. In the current longitudinal study, we investigated the relationships between parental thoughts/actions and neural activation in mothers and fathers in the neonatal period with infant outcomes at the toddler stage. At the first month postpartum, mothers (n=21 and fathers (n=19 underwent a neuroimaging session during which they listened to their own and unfamiliar baby’s cry. Parenting-related thoughts/behaviors were assessed by interview twice at the first month and 3-4 months postpartum and infants’ socioemotional outcomes were reported by mothers and fathers at 18-24 months postpartum. In mothers, higher levels of anxious thoughts/actions about parenting at the first month postpartum, but not at 3-4 months postpartum, were associated with infant’s low socioemotional competencies at 18-24 months. Anxious thoughts/actions were also associated with heightened responses in the motor cortex and reduced responses in the substantia nigra to own infant cry sounds. On the other hand, in fathers, higher levels of positive perception of being a parent at the first month postpartum, but not at 3-4 months postpartum, were associated with higher infant socioemotional competencies at 18-24 months. Positive thoughts were associated with heightened responses in the auditory cortex and caudate to own infant cry sounds. The current study provides evidence that parental thoughts are related to concurrent neural responses to their infants at the first month postpartum as well as their infant’s future socioemotional outcome at 18-24 months. Parent differences suggest that anxious thoughts in mothers and positive thoughts in

  10. From evidence to action. Understanding clinical practice guidelines.

    NARCIS (Netherlands)

    Poolman, R.W.; Verheyen, C.C.P.M.; Kerkhoffs, G.M.; Bhandari, M.; Schünemann, H.J.

    2009-01-01

    Good guidelines will help us to take evidence into practice. In a survey among Dutch orthopedic surgeons, development and use of evidence-based guidelines was perceived as one of the best ways of moving from opinion-based to evidence-based orthopedic practice. The increasing number of guidelines mea

  11. On the inference of agency in operant action : an examination of the cognitive and neural underpinnings in health and schizophrenia

    NARCIS (Netherlands)

    Renes, R.A.

    2016-01-01

    This dissertation elucidates cognitive and neural underpinnings of the sense of agency, which is the feeling that we are in control of our actions and the subsequent consequences. This consciously accessible sensation of control is pervasive, sometimes subtle, and can even be illusory in nature. Fur

  12. Neural strategies for selective attention distinguish fast-action video game players.

    Science.gov (United States)

    Krishnan, Lavanya; Kang, Albert; Sperling, George; Srinivasan, Ramesh

    2013-01-01

    We investigated the psychophysical and neurophysiological differences between fast-action video game players (specifically first person shooter players, FPS) and non-action players (role-playing game players, RPG) in a visual search task. We measured both successful detections (hit rates) and steady-state visually evoked EEG potentials (SSVEPs). Search difficulty was varied along two dimensions: number of adjacent attended and ignored regions (1, 2 and 4), and presentation rate of novel search arrays (3, 8.6 and 20 Hz). Hit rates decreased with increasing presentation rates and number of regions, with the FPS players performing on average better than the RPG players. The largest differences in hit rate, between groups, occurred when four regions were simultaneously attended. We computed signal-to-noise ratio (SNR) of SSVEPs and used partial least squares regression to model hit rates, SNRs and their relationship at 3 Hz and 8.6 Hz. The following are the most significant results: RPG players' parietal responses to the attended 8.6 Hz flicker were predictive of hit rate and were positively correlated with it, indicating attentional signal enhancement. FPS players' parietal responses to the ignored 3 Hz flicker were predictive of hit rate and were positively correlated with it, indicating distractor suppression. Consistent with these parietal responses, RPG players' frontal responses to the attended 8.6 Hz flicker, increased as task difficulty increased with number of regions; FPS players' frontal responses to the ignored 3 Hz flicker increased with number of regions. Thus the FPS players appear to employ an active suppression mechanism to deploy selective attention simultaneously to multiple interleaved regions, while RPG primarily use signal enhancement. These results suggest that fast-action gaming can affect neural strategies and the corresponding networks underlying attention, presumably by training mechanisms of distractor suppression.

  13. Shifted magnetic alignment in vertebrates: Evidence for neural lateralization?

    Science.gov (United States)

    Malkemper, E Pascal; Painter, Michael S; Landler, Lukas

    2016-06-21

    A wealth of evidence provides support for magnetic alignment (MA) behavior in a variety of disparate species within the animal kingdom, in which an animal, or a group of animals, show a tendency to align the body axis in a consistent orientation relative to the geomagnetic field lines. Interestingly, among vertebrates, MA typically coincides with the north-south magnetic axis, however, the mean directional preferences of an individual or group of organisms is often rotated clockwise from the north-south axis. We hypothesize that this shift is not a coincidence, and future studies of this subtle, yet consistent phenomenon may help to reveal some properties of the underlying sensory or processing mechanisms, that, to date, are not well understood. Furthermore, characterizing the fine structure exhibited in MA behaviors may provide key insights to the biophysical substrates mediating magnetoreception in vertebrates. Therefore, in order to determine if a consistent shift is exhibited in taxonomically diverse vertebrates, we performed a meta-analysis on published MA datasets from 23 vertebrate species that exhibited an axial north-south preference. This analysis revealed a significant clockwise shift from the north-south magnetic axis. We summarize and discuss possible competing hypotheses regarding the proximate mechanisms underlying the clockwise shifted MA and conclude that the most likely cause of such a shift would be a lateralization in central processing of magnetic information. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Interaction of sound and sight during action perception: evidence for shared modality-dependent action representations.

    Science.gov (United States)

    Alaerts, Kaat; Swinnen, Stephan P; Wenderoth, Nicole

    2009-10-01

    Seeing or hearing manual actions activates the mirror neuron system, i.e., specialized neurons within motor areas which fire not only when an action is performed but also when it is passively perceived. Although it has been shown that mirror neurons respond to either action-specific vision or sound, it remains a topic of debate whether and how vision and sound interact during action perception. Here we used transcranial magnetic stimulation to explore multimodal interactions in the human motor system, namely at the level of the primary motor cortex (M1). Corticomotor excitability in M1 was measured while subjects perceived unimodal visual (V), unimodal auditory (A), or multimodal (V+A) stimuli of a simple hand action. In addition, incongruent multimodal stimuli were included, in which incongruent vision or sound was presented simultaneously with the auditory or visual action stimulus. A selective response increase was observed to the congruent multimodal stimulus as compared to the unimodal and incongruent multimodal stimuli. These findings speak in favour of 'shared' action representations in the human motor system that are evoked in a 'modality-dependent' way, i.e., they are elicited most robustly by the simultaneous presentation of congruent auditory and visual stimuli. Multimodality in the perception of hand movements bears functional similarities to speech perception, suggesting that multimodal convergence is a generic feature of the mirror system which applies to action perception in general.

  15. The Social Determinants of Tuberculosis: From Evidence to Action

    Science.gov (United States)

    Boccia, Delia; Evans, Carlton A.; Adato, Michelle; Petticrew, Mark; Porter, John D. H.

    2011-01-01

    Growing consensus indicates that progress in tuberculosis control in the low- and middle-income world will require not only investment in strengthening tuberculosis control programs, diagnostics, and treatment but also action on the social determinants of tuberculosis. However, practical ideas for action are scarcer than is notional support for this idea. We developed a framework based on the recent World Health Organization Commission on Social Determinants of Health and on current understanding of the social determinants of tuberculosis. Interventions from outside the health sector—specifically, in social protection and urban planning—have the potential to strengthen tuberculosis control. PMID:21330583

  16. Distinctive laterality of neural networks supporting action understanding in left- and right-handed individuals: An EEG coherence study.

    Science.gov (United States)

    Kelly, Rachel; Mizelle, J C; Wheaton, Lewis A

    2015-08-01

    Prior work has demonstrated that perspective and handedness of observed actions can affect action understanding differently in right and left-handed persons, suggesting potential differences in the neural networks underlying action understanding between right and left-handed individuals. We sought to evaluate potential differences in these neural networks using electroencephalography (EEG). Right- and left-handed participants observed images of tool-use actions from egocentric and allocentric perspectives, with right- and left-handed actors performing the actions. Participants judged the outcome of the observed actions, and response accuracy and latency were recorded. Behaviorally, the highest accuracy and shortest latency was found in the egocentric perspective for right- and left-handed observers. Handedness of subject showed an effect on accuracy and latency also, where right-handed observers were faster to respond than left-handed observers, but on average were less accurate. Mu band (8-10 Hz) cortico-cortical coherence analysis indicated that right-handed observers have coherence in the motor dominant left parietal-premotor networks when looking at an egocentric right or allocentric left hands. When looking in an egocentric perspective at a left hand or allocentric right hand, coherence was lateralized to right parietal-premotor areas. In left-handed observers, bilateral parietal-premotor coherence patterns were observed regardless of actor handedness. These findings suggest that the cortical networks involved in understanding action outcomes are dependent on hand dominance, and notably right handed participants seem to utilize motor systems based on the limb seen performing the action. The decreased accuracy for right-handed participants on allocentric images could be due to asymmetrical lateralization of encoding action and motoric dominance, which may interfere with translating allocentric limb action outcomes. Further neurophysiological studies will

  17. Neural representation of reward probability: evidence from the illusion of control.

    Science.gov (United States)

    Kool, Wouter; Getz, Sarah J; Botvinick, Matthew M

    2013-06-01

    To support reward-based decision-making, the brain must encode potential outcomes both in terms of their incentive value and their probability of occurrence. Recent research has made it clear that the brain bears multiple representations of reward magnitude, meaning that a single choice option may be represented differently-and even inconsistently-in different brain areas. There are some hints that the same may be true for reward probability. Preliminary evidence hints that, even as systematic distortions of probability are expressed in behavior, these may not always be uniformly reflected at the neural level: Some neural representations of probability may be immune from such distortions. This study provides new evidence consistent with this possibility. Participants in a behavioral experiment displayed a classic "illusion of control," providing higher estimates of reward probability for gambles they had chosen than for identical gambles that were imposed on them. However, an fMRI study of the same task revealed that neural prediction error signals, arising when gamble outcomes were revealed, were unaffected by the illusion of control. The resulting behavioral-neural dissociation reinforces the case for multiple, inconsistent internal representations of reward probability, while also prompting a reinterpretation of the illusion of control effect itself.

  18. Effects of action observation therapy and mirror therapy after stroke on rehabilitation outcomes and neural mechanisms by MEG: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Shih, Tsai-Yu; Wu, Ching-Yi; Lin, Keh-Chung; Cheng, Chia-Hsiung; Hsieh, Yu-Wei; Chen, Chia-Ling; Lai, Chih-Jou; Chen, Chih-Chi

    2017-10-04

    Loss of upper-extremity motor function is one of the most debilitating deficits following stroke. Two promising treatment approaches, action observation therapy (AOT) and mirror therapy (MT), aim to enhance motor learning and promote neural reorganization in patients through different afferent inputs and patterns of visual feedback. Both approaches involve different patterns of motor observation, imitation, and execution but share some similar neural bases of the mirror neuron system. AOT and MT used in stroke rehabilitation may confer differential benefits and neural activities that remain to be determined. This clinical trial aims to investigate and compare treatment effects and neural activity changes of AOT and MT with those of the control intervention in patients with subacute stroke. An estimated total of 90 patients with subacute stroke will be recruited for this study. All participants will be randomly assigned to receive AOT, MT, or control intervention for a 3-week training period (15 sessions). Outcome measurements will be taken at baseline, immediately after treatment, and at the 3-month follow-up. For the magnetoencephalography (MEG) study, we anticipate that we will recruit 12 to 15 patients per group. The primary outcome will be the Fugl-Meyer Assessment score. Secondary outcomes will include the modified Rankin Scale, the Box and Block Test, the ABILHAND questionnaire, the Questionnaire Upon Mental Imagery, the Functional Independence Measure, activity monitors, the Stroke Impact Scale version 3.0, and MEG signals. This clinical trial will provide scientific evidence of treatment effects on motor, functional outcomes, and neural activity mechanisms after AOT and MT in patients with subacute stroke. Further application and use of AOT and MT may include telerehabilitation or home-based rehabilitation through web-based or video teaching. ClinicalTrials.gov, ID: NCT02871700 . Registered on 1 August 2016.

  19. Evidence for a distributed hierarchy of action representation in the brain

    Science.gov (United States)

    Grafton, Scott T.; de C. Hamilton, Antonia F.

    2007-01-01

    Complex human behavior is organized around temporally distal outcomes. Behavioral studies based on tasks such as normal prehension, multi-step object use and imitation establish the existence of relative hierarchies of motor control. The retrieval errors in apraxia also support the notion of a hierarchical model for representing action in the brain. In this review, three functional brain imaging studies of action observation using the method of repetition suppression are used to identify a putative neural architecture that supports action understanding at the level of kinematics, object centered goals and ultimately, motor outcomes. These results, based on observation, may match a similar functional anatomic hierarchy for action planning and execution. If this is true, then the findings support a functional anatomic model that is distributed across a set of interconnected brain areas that are differentially recruited for different aspects of goal oriented behavior, rather than a homogeneous mirror neuron system for organizing and understanding all behavior. PMID:17706312

  20. Neural Signatures of the Response to Emotional Distraction: A Review of Evidence from Brain Imaging Investigations

    Directory of Open Access Journals (Sweden)

    Alexandru D Iordan

    2013-06-01

    Full Text Available Prompt responses to emotional, potentially threatening, stimuli are supported by neural mechanisms that allow for privileged access of emotional information to processing resources. The existence of these mechanisms can also make emotional stimuli potent distracters, particularly when task-irrelevant. The ability to deploy cognitive control in order to cope with emotional distraction is essential for adaptive behavior, while reduced control may lead to enhanced emotional distractibility, which is often a hallmark of affective disorders. Evidence suggests that increased susceptibility to emotional distraction is linked to changes in the processing of emotional information that affect both the basic response to and coping with emotional distraction, but the neural correlates of these phenomena are not clear. The present review discusses emerging evidence from brain imaging studies addressing these issues, and highlights the following three aspects. First, the response to emotional distraction is associated with opposing patterns of activity in a ventral ‘hot’ affective system (HotEmo, showing increased activity and a dorsal ‘cold’ executive system (ColdEx, showing decreased activity. Second, coping with emotional distraction involves top-down control in order to counteract the bottom-up influence of emotional distraction, and involves interactions between the amygdala and the prefrontal cortex. Third, both the response to and coping with emotional distraction are influenced by individual differences affecting emotional sensitivity and distractibility, which are linked to alterations of both HotEmo and ColdEx neural systems. Collectively, the available evidence identifies specific neural signatures of the response to emotional challenge, which are fundamental to understanding the mechanisms of emotion-cognition interactions in healthy functioning, and the changes linked to individual variation in emotional distractibility and susceptibility

  1. The Music of Your Emotions: Neural Substrates Involved in Detection of Emotional Correspondence between Auditory and Visual Music Actions

    OpenAIRE

    Petrini, K.; Crabbe, F.; Sheridan, C; Pollick, Frank

    2011-01-01

    In humans, emotions from music serve important communicative roles. Despite a growing interest in the neural basis of music perception, action and emotion, the majority of previous studies in this area have focused on the auditory aspects of music performances. Here we investigate how the brain processes the emotions elicited by audiovisual music performances. We used event-related functional magnetic resonance imaging, and in Experiment 1 we defined the areas responding to audiovisual (music...

  2. Self-reported empathy and neural activity during action imitation and observation in schizophrenia

    Directory of Open Access Journals (Sweden)

    William P. Horan

    2014-01-01

    Conclusions: Although patients with schizophrenia demonstrated largely normal patterns of neural activation across the finger movement and facial expression tasks, they reported decreased self perceived empathy and failed to show the typical relationship between neural activity and self-reported empathy seen in controls. These findings suggest that patients show a disjunction between automatic neural responses to low level social cues and higher level, integrative social cognitive processes involved in self-perceived empathy.

  3. Enhanced Neural Processing of Goal-directed Actions After Active Training in 4-Month-Old Infants.

    Science.gov (United States)

    Bakker, Marta; Sommerville, Jessica A; Gredebäck, Gustaf

    2016-03-01

    The current study explores the neural correlates of action perception and its relation to infants' active experience performing goal-directed actions. Study 1 provided active training with sticky mittens that enables grasping and object manipulation in prereaching 4-month-olds. After training, EEG was recorded while infants observed images of hands grasping toward (congruent) or away from (incongruent) objects. We demonstrate that brief active training facilitates social perception as indexed by larger amplitude of the P400 ERP component to congruent compared with incongruent trials. Study 2 presented 4-month-old infants with passive training in which they observed an experimenter perform goal-directed reaching actions, followed by an identical ERP session to that used in Study 1. The second study did not demonstrate any differentiation between congruent and incongruent trials. These results suggest that (1) active experience alters the brains' response to goal-directed actions performed by others and (2) visual exposure alone is not sufficient in developing the neural networks subserving goal processing during action observation in infancy.

  4. Do Bans on Affirmative Action Hurt Minority Students? Evidence from the Texas Top 10% Plan

    Science.gov (United States)

    Cortes, Kalena E.

    2010-01-01

    In light of the recent bans on affirmative action in higher education, this paper provides new evidence on the effects of alternative admissions policies on the persistence and college completion of minority students. I find that the change from affirmative action to the Top 10% Plan in Texas decreased both retention and graduation rates of…

  5. Recognition of the physiological actions of the triphasic EMG pattern by a dynamic recurrent neural network.

    Science.gov (United States)

    Cheron, Guy; Cebolla, Ana Maria; Bengoetxea, Ana; Leurs, Françoise; Dan, Bernard

    2007-03-06

    Triphasic electromyographic (EMG) patterns with a sequence of activity in agonist (AG1), antagonist (ANT) and again in agonist (AG2) muscles are characteristic of ballistic movements. They have been studied in terms of rectangular pulse-width or pulse-height modulation. In order to take into account the complexity of the EMG signal within the bursts, we used a dynamic recurrent neural network (DRNN) for the identification of this pattern in subjects performing fast elbow flexion movements. Biceps and triceps EMGs were fed to all 35 fully-connected hidden units of the DRNN for mapping onto elbow angular acceleration signals. DRNN training was supervised, involving learning rule adaptations of synaptic weights and time constants of each unit. We demonstrated that the DRNN is able to perfectly reproduce the acceleration profile of the ballistic movements. Then we tested the physiological plausibility of all the networks that reached an error level below 0.001 by selectively increasing the amplitude of each burst of the triphasic pattern and evaluating the effects on the simulated accelerating profile. Nineteen percent of these simulations reproduced the physiological action classically attributed to the 3 EMG bursts: AG1 increase showed an increase of the first accelerating pulse, ANT an increase of the braking pulse and AG2 an increase of the clamping pulse. These networks also recognized the physiological function of the time interval between AG1 and ANT, reproducing the linear relationship between time interval and movement amplitude. This task-dynamics recognition has implications for the development of DRNN as diagnostic tools and prosthetic controllers.

  6. The grammar of visual narrative: Neural evidence for constituent structure in sequential image comprehension.

    Science.gov (United States)

    Cohn, Neil; Jackendoff, Ray; Holcomb, Phillip J; Kuperberg, Gina R

    2014-11-01

    Constituent structure has long been established as a central feature of human language. Analogous to how syntax organizes words in sentences, a narrative grammar organizes sequential images into hierarchic constituents. Here we show that the brain draws upon this constituent structure to comprehend wordless visual narratives. We recorded neural responses as participants viewed sequences of visual images (comics strips) in which blank images either disrupted individual narrative constituents or fell at natural constituent boundaries. A disruption of either the first or the second narrative constituent produced a left-lateralized anterior negativity effect between 500 and 700ms. Disruption of the second constituent also elicited a posteriorly-distributed positivity (P600) effect. These neural responses are similar to those associated with structural violations in language and music. These findings provide evidence that comprehenders use a narrative structure to comprehend visual sequences and that the brain engages similar neurocognitive mechanisms to build structure across multiple domains.

  7. Cervical cancer control in India: taking evidence to action.

    Science.gov (United States)

    Farooqui, Habib Hasan; Zodpey, Sanjay

    2012-05-01

    The most prevalent types of human papillomavirus in cervical cancer in India are HPV 16 and HPV 18, found in 60.7 per cent and 16 per cent of cases respectively. A comprehensive strategy with a judicious mix of interventions on health promotion, specific protection (vaccination), early diagnosis (screening), and treatment should be instituted to prevent and control cervical cancer in India. Proponents of vaccination and screening argue for enhanced investments on these interventions based on their relative cost-effectiveness. For policymakers, the major concerns about these interventions remain affordability and cost to government. Herein we try to review comprehensively the evidence on prevention and control interventions and to recommend appropriate policies to guide public health decision-making.

  8. Evidence for sex-specific shifting of neural processes underlying learning and memory following stress.

    Science.gov (United States)

    Beck, Kevin D; Luine, Victoria N

    2010-02-09

    Recent human research has been focused upon determining whether there is evidence that stress responses cause qualitative changes in neural activity such that people change their learning strategies from a spatial/contextual memory process through the hippocampus to a procedural stimulus-response process through the caudate nucleus. Moreover, interest has shifted to determining whether males and females exhibit the same type of stress-induced change in neural processing of associations. Presented is a select review of 2 different animal models that have examined how acute or chronic stressors change learning in a sex-specific manner. This is followed by a brief review of recent human studies documenting how learning and memory functions change following stressor exposure. In both cases, it is clear that ovarian hormones have a significant influence on how stress affects learning processes in females. We then examine the evidence for a role of acetylcholine, dopamine, norepinephrine, or serotonin in modulating this shifting of processing and how that may differ across sex. Conclusions drawn suggest that there may be evidence for sex-specific changes in amygdala and hippocampus neuromodulation; however, the behavioral data are still not conclusive as to whether this represents a common or sex-specific shift in how males and females process associations after stressor exposure.

  9. Neural encoding of acupuncture needling sensations: evidence from a FMRI study.

    Science.gov (United States)

    Wang, Xiaoling; Chan, Suk-Tak; Fang, Jiliang; Nixon, Erika E; Liu, Jing; Kwong, Kenneth K; Rosen, Bruce R; Hui, Kathleen K S

    2013-01-01

    Deqi response, a psychophysical response characterized by a spectrum of different needling sensations, is essential for Chinese acupuncture clinical efficacy. Previous neuroimaging research works have investigated the neural correlates of an overall deqi response by summating the scores of different needling sensations. However, the roles of individual sensations in brain activity and how they interact with each other remain to be clarified. In this study, we applied fMRI to investigate the neural correlates of individual components of deqi during acupuncture on the right LV3 (Taichong) acupoint. We selected a subset of deqi responses, namely, pressure, heaviness, fullness, numbness, and tingling. Using the individual components of deqi of different subjects as covariates in the analysis of percentage change of bold signal, pressure was found to be a striking sensation, contributing to most of negative activation of a limbic-paralimbic-neocortical network (LPNN). The similar or opposite neural activity in the heavily overlapping regions is found to be responding to different needling sensations, including bilateral LPNN, right orbitofrontal cortex, and bilateral posterior parietal cortex. These findings provide the neuroimaging evidence of how the individual needle sensations interact in the brain, showing that the modulatory effects of different needling sensations contribute to acupuncture modulations of LPNN network.

  10. Neural Encoding of Acupuncture Needling Sensations: Evidence from a fMRI Study

    Directory of Open Access Journals (Sweden)

    Xiaoling Wang

    2013-01-01

    Full Text Available Deqi response, a psychophysical response characterized by a spectrum of different needling sensations, is essential for Chinese acupuncture clinical efficacy. Previous neuroimaging research works have investigated the neural correlates of an overall deqi response by summating the scores of different needling sensations. However, the roles of individual sensations in brain activity and how they interact with each other remain to be clarified. In this study, we applied fMRI to investigate the neural correlates of individual components of deqi during acupuncture on the right LV3 (Taichong acupoint. We selected a subset of deqi responses, namely, pressure, heaviness, fullness, numbness, and tingling. Using the individual components of deqi of different subjects as covariates in the analysis of percentage change of bold signal, pressure was found to be a striking sensation, contributing to most of negative activation of a limbic-paralimbic-neocortical network (LPNN. The similar or opposite neural activity in the heavily overlapping regions is found to be responding to different needling sensations, including bilateral LPNN, right orbitofrontal cortex, and bilateral posterior parietal cortex. These findings provide the neuroimaging evidence of how the individual needle sensations interact in the brain, showing that the modulatory effects of different needling sensations contribute to acupuncture modulations of LPNN network.

  11. Variations in retrieval monitoring during action memory judgments: evidence from event-related potentials (ERPs).

    Science.gov (United States)

    Leynes, P Andrew; Kakadia, Bhavika

    2013-02-01

    The present study investigated the neuroscience of memory for actions using event-related potentials (ERPs). Actions were performed, initiated but not completed (i.e., interrupted), or watched while the experimenter performed the action during encoding. Memory was assessed in a reality monitoring (RM) test (performed vs. watched actions), as well as in an internal source monitoring (ISM) test (performed vs. interrupted) while ERPs were recorded. Behavioral measures provided evidence of robust old/new recognition for all actions, but the analysis of source errors revealed that interrupted actions were often confused with performed actions. The ERP correlate of recollection, the parietal "old/new" effect (700-900ms), was observed for all actions. The right frontal "old/new" effect (1500-1800ms) that correlates with general memory monitoring was observed in RM but not in ISM. Instead, ISM was associated with the late posterior negativity (LPN) that has been connected to more specific memory monitoring. This pattern of ERP findings suggest that, in this context, general monitoring was used to discriminate self- versus other-performed actions, whereas more specific monitoring was required to support the discrimination of completed and interrupted actions. We argue that the mix of general/specific monitoring processes is shaped by the global retrieval context, which includes the number of memory features that overlap and the combination of sources being considered among other factors.

  12. Recognizing Combinations of Facial Action Units with Different Intensity Using a Mixture of Hidden Markov Models and Neural Network

    CERN Document Server

    Khademi, Mahmoud; Kiapour, Mohammad H; Kiaei, Ali A

    2010-01-01

    Facial Action Coding System consists of 44 action units (AUs) and more than 7000 combinations. Hidden Markov models (HMMs) classifier has been used successfully to recognize facial action units (AUs) and expressions due to its ability to deal with AU dynamics. However, a separate HMM is necessary for each single AU and each AU combination. Since combinations of AU numbering in thousands, a more efficient method will be needed. In this paper an accurate real-time sequence-based system for representation and recognition of facial AUs is presented. Our system has the following characteristics: 1) employing a mixture of HMMs and neural network, we develop a novel accurate classifier, which can deal with AU dynamics, recognize subtle changes, and it is also robust to intensity variations, 2) although we use an HMM for each single AU only, by employing a neural network we can recognize each single and combination AU, and 3) using both geometric and appearance-based features, and applying efficient dimension reducti...

  13. Evaluation of the legal consequences of action affects neural activity and emotional experience during the resolution of moral dilemmas.

    Science.gov (United States)

    Pletti, Carolina; Sarlo, Michela; Palomba, Daniela; Rumiati, Rino; Lotto, Lorella

    2015-03-01

    In any modern society killing is regarded as a severe violation of the legal codes that is subjected to penal judgment. Therefore, it is likely that people take legal consequences into account when deciding about the hypothetical killing of one person in classic moral dilemmas, with legal concerns contributing to decision-making. In particular, by differing for the degree of intentionality and emotional salience, Footbridge- and Trolley-type dilemmas might promote differential assignment of blame and punishment while implicating the same severity of harm. The present study was aimed at comparing the neural activity, subjective emotional reactions, and behavioral choices in two groups of participants who either took (Legal group) or did not take (No Legal group) legal consequences into account when deciding on Footbridge-type and Trolley-type moral dilemmas. Stimulus- and response-locked ERPs were measured to investigate the neural activity underlying two separate phases of the decision process. No difference in behavioral choices was found between groups. However, the No Legal group reported greater overall emotional impact, associated with lower preparation for action, suggesting greater conflict between alternative motor responses representing the different decision choices. In contrast, the Legal group showed an overall dampened affective experience during decision-making associated with greater overall action readiness and intention to act, reflecting lower conflict in responding. On these bases, we suggest that in moral dilemmas legal consequences of actions provide a sort of reference point on which people can rely to support a decision, independent of dilemma type.

  14. The porous boundaries between explicit and implicit memory: behavioral and neural evidence.

    Science.gov (United States)

    Dew, Ilana T Z; Cabeza, Roberto

    2011-04-01

    Explicit memory refers to the conscious retrieval of past information or experiences, whereas implicit memory refers to an unintentional or nonconscious form of retrieval. Much of the literature in cognitive psychology and cognitive neuroscience has focused on differences between explicit and implicit memory, and the traditional view is that they rely on distinct brain systems. However, the potential interplay between implicit and explicit memory is not always clear. This review draws from behavioral and functional neuroimaging evidence to evaluate three areas in which implicit and explicit memory may be interrelated. First, we discuss views of familiarity-based recognition in terms of its relationship with implicit memory. Second, we review the challenges of distinguishing between implicit memory and involuntary aware memory, at both behavioral and neural levels. Finally, we examine evidence indicating that implicit and explicit retrieval of relational information may rely on a common neural mechanism. Taken together, these areas indicate that, under certain circumstances, there may be an important and influential relationship between conscious and nonconscious expressions of memory.

  15. Do bans on affirmative action hurt minority students? Evidence from the Texas Top 10% Plan

    OpenAIRE

    2010-01-01

    In light of the recent bans on affirmative action in higher education, this paper provides new evidence on the effects of alternative admissions policies on the persistence and college completion of minority students. I find that the change from affirmative action to the Top 10% Plan in Texas decreased both retention and graduation rates of lower-ranked minority students. Results show that both fall-to-fall freshmen retention and six-year college graduation of seconddecile minority students d...

  16. Interactions between auditory and visual semantic stimulus classes: evidence for common processing networks for speech and body actions.

    Science.gov (United States)

    Meyer, Georg F; Greenlee, Mark; Wuerger, Sophie

    2011-09-01

    Incongruencies between auditory and visual signals negatively affect human performance and cause selective activation in neuroimaging studies; therefore, they are increasingly used to probe audiovisual integration mechanisms. An open question is whether the increased BOLD response reflects computational demands in integrating mismatching low-level signals or reflects simultaneous unimodal conceptual representations of the competing signals. To address this question, we explore the effect of semantic congruency within and across three signal categories (speech, body actions, and unfamiliar patterns) for signals with matched low-level statistics. In a localizer experiment, unimodal (auditory and visual) and bimodal stimuli were used to identify ROIs. All three semantic categories cause overlapping activation patterns. We find no evidence for areas that show greater BOLD response to bimodal stimuli than predicted by the sum of the two unimodal responses. Conjunction analysis of the unimodal responses in each category identifies a network including posterior temporal, inferior frontal, and premotor areas. Semantic congruency effects are measured in the main experiment. We find that incongruent combinations of two meaningful stimuli (speech and body actions) but not combinations of meaningful with meaningless stimuli lead to increased BOLD response in the posterior STS (pSTS) bilaterally, the left SMA, the inferior frontal gyrus, the inferior parietal lobule, and the anterior insula. These interactions are not seen in premotor areas. Our findings are consistent with the hypothesis that pSTS and frontal areas form a recognition network that combines sensory categorical representations (in pSTS) with action hypothesis generation in inferior frontal gyrus/premotor areas. We argue that the same neural networks process speech and body actions.

  17. Action observation as a useful approach for enhancing recovery of verb production: new evidence from aphasia.

    Science.gov (United States)

    Bonifazi, S; Tomaiuolo, F; Altoè, G; Ceravolo, M G; Provinciali, L; Marangolo, P

    2013-08-01

    Evidence exists that the observation of actions performed by others enhance word retrieval and can be used in aphasia rehabilitation to treat naming impairments. The aim of the present study was to assess to what extent action observation treatment may improve verb retrieval in chronic aphasics. This was an observational study. Patients were recruited from the Neurorehabilitation Centre of Ancona Hospital. Six aphasic patients underwent an intensive language training to improve verb naming. Language evaluation was carried out before and after the treatment. A rehabilitation therapy based on observation of actions was administered daily to each patient for two consecutive weeks. Four different rehabilitation procedures were adopted: 1) "observation of action performed by the examiner"; 2) "observation and then execution of action"; 3) "observation of videoclips of actions"; and, as a control condition; 4) "observation of action and execution of meaningless movement". In four participants, a significant improvement in verb retrieval was found for the three experimental procedures (χ² (3)=75.212, Pobserved in the two patients with severe deficits in verb semantics (χ² (3)=0.592, P=0.892). Action observation therapy may become a useful intervention strategy to promote verb retrieval in aphasic patients. The observation of videoclips of actions may be an efficacious alternative approach to traditional rehabilitation programs for lexical deficits. This finding endorses the planning of innovative low-cost interventions in language rehabilitation.

  18. Comparative investigations of manual action representations: evidence that chimpanzees represent the costs of potential future actions involving tools.

    Science.gov (United States)

    Frey, Scott H; Povinelli, Daniel J

    2012-01-12

    The ability to adjust one's ongoing actions in the anticipation of forthcoming task demands is considered as strong evidence for the existence of internal action representations. Studies of action selection in tool use reveal that the behaviours that we choose in the present moment differ depending on what we intend to do next. Further, they point to a specialized role for mechanisms within the human cerebellum and dominant left cerebral hemisphere in representing the likely sensory costs of intended future actions. Recently, the question of whether similar mechanisms exist in other primates has received growing, but still limited, attention. Here, we present data that bear on this issue from a species that is a natural user of tools, our nearest living relative, the chimpanzee. In experiment 1, a subset of chimpanzees showed a non-significant tendency for their grip preferences to be affected by anticipation of the demands associated with bringing a tool's baited end to their mouths. In experiment 2, chimpanzees' initial grip preferences were consistently affected by anticipation of the forthcoming movements in a task that involves using a tool to extract a food reward. The partial discrepancy between the results of these two studies is attributed to the ability to accurately represent differences between the motor costs associated with executing the two response alternatives available within each task. These findings suggest that chimpanzees are capable of accurately representing the costs of intended future actions, and using those predictions to select movements in the present even in the context of externally directed tool use.

  19. Knowing when not to swing: EEG evidence that enhanced perception-action coupling underlies baseball batter expertise.

    Science.gov (United States)

    Muraskin, Jordan; Sherwin, Jason; Sajda, Paul

    2015-12-01

    Given a decision that requires less than half a second for evaluating the characteristics of the incoming pitch and generating a motor response, hitting a baseball potentially requires unique perception-action coupling to achieve high performance. We designed a rapid perceptual decision-making experiment modeled as a Go/No-Go task yet tailored to reflect a real scenario confronted by a baseball hitter. For groups of experts (Division I baseball players) and novices (non-players), we recorded electroencephalography (EEG) while they performed the task. We analyzed evoked EEG single-trial variability, contingent negative variation (CNV), and pre-stimulus alpha power with respect to the expert vs. novice groups. We found strong evidence for differences in inhibitory processes between the two groups, specifically differential activity in supplementary motor areas (SMA), indicative of enhanced inhibitory control in the expert (baseball player) group. We also found selective activity in the fusiform gyrus (FG) and orbital gyrus in the expert group, suggesting an enhanced perception-action coupling in baseball players that differentiates them from matched controls. In sum, our results show that EEG correlates of decision formation can be used to identify neural markers of high-performance athletes. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Evidence-Based Practice and School Libraries: Interconnections of Evidence, Advocacy, and Actions

    Science.gov (United States)

    Todd, Ross J.

    2015-01-01

    This author states that a professional focus on evidence based practice (EBP) for school libraries emerged from the International Association of School Librarianship conference when he presented the concept. He challenged the school library profession to actively engage in professional and reflective practices that chart, measure, document, and…

  1. Dissociable neural systems for timing: evidence from subjects with basal ganglia lesions.

    Directory of Open Access Journals (Sweden)

    H Branch Coslett

    Full Text Available BACKGROUND: The neural basis of timing remains poorly understood. Although controversy persists, many lines of evidence, including studies in animals, functional imaging studies in humans and lesion studies in humans and animals suggest that the basal ganglia are important for temporal processing [1]. METHODOLOGY/PRINCIPAL FINDINGS: We report data from a wide range of timing tasks from two subjects with disabling neurologic deficits caused by bilateral lesions of the basal ganglia. Both subjects perform well on tasks assessing time estimation, reproduction and production tasks. Additionally, one subject performed normally on psychophysical tasks requiring the comparison of time intervals ranging from milliseconds to seconds; the second subject performed abnormally on the psychophysical task with a 300ms standard but did well with 600ms, 2000ms and 8000ms standards. Both subjects performed poorly on an isochronous rhythm production task on which they are required to maintain rhythmic tapping. CONCLUSIONS/SIGNIFICANCE: As studies of subjects with brain lesions permit strong inferences regarding the necessity of brain structures, these data demonstrate that the basal ganglia are not crucial for many sub- or supra-second timing operations in humans but are needed for the timing procedures that underlie the production of movements. This dissociation suggests that distinct and dissociable processes may be employed to measure time intervals. Inconsistencies in findings regarding the neural basis of timing may reflect the availability of multiple temporal processing routines that are flexibly implemented in response to task demands.

  2. Promoting Student Engagement through Evidence-Based Action Research with Teachers

    Science.gov (United States)

    Strambler, Michael J.; McKown, Clark

    2013-01-01

    We present findings from a group-randomized teacher action research intervention to promote academic engagement and achievement among elementary school students. Eighteen teachers from 3 elementary schools were randomly assigned to 1 of 2 groups. Intervention teachers studied evidence-based instructional practices that cultivate academic…

  3. Neural mechanisms of time-based prospective memory: evidence for transient monitoring.

    Directory of Open Access Journals (Sweden)

    Kevin M Oksanen

    Full Text Available In daily life, we often need to remember to perform an action after, or at, a specific period of time (e.g., take pizza out of oven in 15 minutes. Surprisingly, little is known about the neural mechanisms that support this form of memory, termed time-based prospective memory (PM. Here we pioneer an fMRI paradigm that enables examination of both sustained and transient processes engaged during time-based PM. Participants were scanned while performing a demanding on-going task (n-back working memory, with and without an additional time-based PM demand. During the PM condition participants could access a hidden clock with a specific button-press response, while in the control condition, pseudo-clocks randomly appeared and were removed via the same response. Analyses tested for sustained activation associated with the PM condition, and also transient activation associated with clock-checks and the PM target response. Contrary to prior findings with event-based PM (i.e., remembering to perform a future action when a specific event occurs, no sustained PM-related activity was observed in anterior prefrontal cortex (aPFC or elsewhere in the brain; instead, transient clock-related activity was observed in this region. Critically, the activation was anticipatory, increasing before clock-check responses. Anticipatory activity prior to the PM target response was weaker in aPFC, but strong in pre-Supplementary Motor Area (pre-SMA; relative to clock-check responses, suggesting a functional double dissociation related to volitional decision-making. Together, the results suggest that aPFC-activity dynamics during time-based PM reflect a distinct transient monitoring process, enabling integration of the PM intention with current temporal information to facilitate scheduling of upcoming PM-related actions.

  4. Neural evidence for description dependent reward processing in the framing effect.

    Science.gov (United States)

    Yu, Rongjun; Zhang, Ping

    2014-01-01

    Human decision making can be influenced by emotionally valenced contexts, known as the framing effect. We used event-related brain potentials to investigate how framing influences the encoding of reward. We found that the feedback related negativity (FRN), which indexes the "worse than expected" negative prediction error in the anterior cingulate cortex (ACC), was more negative for the negative frame than for the positive frame in the win domain. Consistent with previous findings that the FRN is not sensitive to "better than expected" positive prediction error, the FRN did not differentiate the positive and negative frame in the loss domain. Our results provide neural evidence that the description invariance principle which states that reward representation and decision making are not influenced by how options are presented is violated in the framing effect.

  5. Neural and Behavioral Evidence for Infants' Sensitivity to the Trustworthiness of Faces.

    Science.gov (United States)

    Jessen, Sarah; Grossmann, Tobias

    2016-11-01

    Face evaluation is a key aspect of face processing in humans, serving important functions in regulating social interactions. Adults and preschool children readily evaluate faces with respect to a person's trustworthiness and dominance. However, it is unclear whether face evaluation is mainly a product of extensive learning or a foundational building block of face perception already during infancy. We examined infants' sensitivity to facial signs of trustworthiness (Experiment 1) and dominance (Experiment 2) by measuring ERPs and looking behavior in response to faces that varied with respect to the two facial attributes. Results revealed that 7-month-old infants are sensitive to facial signs of trustworthiness but not dominance. This sensitivity was reflected in infants' behavioral preference and in the modulation of brain responses previously linked to emotion detection from faces. These findings provide first evidence that processing faces with respect to trustworthiness has its origins in infancy and shed light on the behavioral and neural correlates of this early emerging sensitivity.

  6. Action Mechanisms for Social Cognition: Behavioral and Neural Correlates of Developing Theory of Mind

    Science.gov (United States)

    Bowman, Lindsay C.; Thorpe, Samuel G.; Cannon, Erin N.; Fox, Nathan A.

    2017-01-01

    Many psychological theories posit foundational links between two fundamental constructs: (1) our ability to produce, perceive, and represent action; and (2) our ability to understand the meaning and motivation behind the action (i.e. Theory of Mind; ToM). This position is contentious, however, and long-standing competing theories of…

  7. Neurocognitive mechanisms underlying social learning in infancy: infants' neural processing of the effects of others' actions.

    Science.gov (United States)

    Paulus, Markus; Hunnius, Sabine; Bekkering, Harold

    2013-10-01

    Social transmission of knowledge is one of the reasons for human evolutionary success, and it has been suggested that already human infants possess eminent social learning abilities. However, nothing is known about the neurocognitive mechanisms that subserve infants' acquisition of novel action knowledge through the observation of other people's actions and their consequences in the physical world. In an electroencephalogram study on social learning in infancy, we demonstrate that 9-month-old infants represent the environmental effects of others' actions in their own motor system, although they never achieved these effects themselves before. The results provide first insights into the neurocognitive basis of human infants' unique ability for social learning of novel action knowledge.

  8. Cognitive enhancement through action video game training: great expectations require greater evidence.

    Science.gov (United States)

    Bisoglio, Joseph; Michaels, Timothy I; Mervis, Joshua E; Ashinoff, Brandon K

    2014-01-01

    Action video game training may hold promise as a cognitive intervention with the potential to enhance daily functioning and remediate impairments, but this must be more thoroughly evaluated through evidence-based practices. We review current research on the effect of action video game training on visual attention and visuospatial processing, executive functions, and learning and memory. Focusing on studies that utilize strict experimental controls and synthesize behavioral and neurophysiological data, we examine whether there is sufficient evidence to support a causal relationship between action video game training and beneficial changes in cognition. Convergent lines of behavioral and neurophysiological evidence tentatively support the efficacy of training, but the magnitude and specificity of these effects remain obscure. Causal inference is thus far limited by a lack of standardized and well-controlled methodology. Considering future directions, we suggest stringent adherence to evidence-based practices and collaboration modeled after clinical trial networks. Finally, we recommend the exploration of more complex causal models, such as indirect causal relationships and interactions that may be masking true effects.

  9. Will Increasing Folic Acid in Fortified Grain Products Further Reduce Neural Tube Defects without Causing Harm?: Consideration of the Evidence

    Science.gov (United States)

    Will Increasing Folic Acid in Fortified Grain Products Further Reduce Neural Tube Defects without Causing Harm?: Consideration of the Evidence. In the January issue of this journal, Johnston (1) includes our group’s recent analysis of data from the 1999-2002 National Health and Nutrition Examination...

  10. Neural alpha oscillations index the balance between self-other integration and segregation in real-time joint action.

    Science.gov (United States)

    Novembre, Giacomo; Sammler, Daniela; Keller, Peter E

    2016-08-01

    Shared knowledge and interpersonal coordination are prerequisites for most forms of social behavior. Influential approaches to joint action have conceptualized these capacities in relation to the separate constructs of co-representation (knowledge) and self-other entrainment (coordination). Here we investigated how brain mechanisms involved in co-representation and entrainment interact to support joint action. To do so, we used a musical joint action paradigm to show that the neural mechanisms underlying co-representation and self-other entrainment are linked via a process - indexed by EEG alpha oscillations - regulating the balance between self-other integration and segregation in real time. Pairs of pianists performed short musical items while action familiarity and interpersonal (behavioral) synchronization accuracy were manipulated in a factorial design. Action familiarity referred to whether or not pianists had rehearsed the musical material performed by the other beforehand. Interpersonal synchronization was manipulated via congruent or incongruent tempo change instructions that biased performance timing towards the impending, new tempo. It was observed that, when pianists were familiar with each other's parts, millisecond variations in interpersonal synchronized behavior were associated with a modulation of alpha power over right centro-parietal scalp regions. Specifically, high behavioral entrainment was associated with self-other integration, as indexed by alpha suppression. Conversely, low behavioral entrainment encouraged reliance on internal knowledge and thus led to self-other segregation, indexed by alpha enhancement. These findings suggest that alpha oscillations index the processing of information about self and other depending on the compatibility of internal knowledge and external (environmental) events at finely resolved timescales.

  11. Enhancement of cognitive and neural functions through complex reasoning training: evidence from normal and clinical populations.

    Science.gov (United States)

    Chapman, Sandra B; Mudar, Raksha A

    2014-01-01

    Public awareness of cognitive health is fairly recent compared to physical health. Growing evidence suggests that cognitive training offers promise in augmenting cognitive brain performance in normal and clinical populations. Targeting higher-order cognitive functions, such as reasoning in particular, may promote generalized cognitive changes necessary for supporting the complexities of daily life. This data-driven perspective highlights cognitive and brain changes measured in randomized clinical trials that trained gist reasoning strategies in populations ranging from teenagers to healthy older adults, individuals with brain injury to those at-risk for Alzheimer's disease. The evidence presented across studies support the potential for Gist reasoning training to strengthen cognitive performance in trained and untrained domains and to engage more efficient communication across widespread neural networks that support higher-order cognition. The meaningful benefits of Gist training provide compelling motivation to examine optimal dose for sustained benefits as well as to explore additive benefits of meditation, physical exercise, and/or improved sleep in future studies.

  12. Enhancement of Cognitive and Neural Functions through Complex Reasoning Training: Evidence from Normal and Clinical Populations

    Directory of Open Access Journals (Sweden)

    Sandra Bond Chapman

    2014-04-01

    Full Text Available Public awareness of cognitive health is fairly recent compared to physical health. Growing evidence suggests that cognitive training offers promise in augmenting cognitive brain performance in normal and clinical populations. Targeting higher-order cognitive functions, such as reasoning in particular, may promote generalized cognitive changes necessary for supporting the complexities of daily life. This data-driven perspective highlights cognitive and brain changes measured in randomized clinical trials that trained gist reasoning strategies in populations ranging from teenagers to healthy older adults, individuals with brain injury to those at-risk for Alzheimer’s disease. The evidence presented across studies support the potential for Gist reasoning training to strengthen cognitive performance in trained and untrained domains and to engage more efficient communication across widespread neural networks that support higher-order cognition. The meaningful benefits of Gist training provide compelling motivation to examine optimal dose for sustained benefits as well as to explore additive benefits of meditation, physical exercise, and/or improved sleep in future studies.

  13. The 'fractionable autism triad': a review of evidence from behavioural, genetic, cognitive and neural research.

    Science.gov (United States)

    Happé, Francesca; Ronald, Angelica

    2008-12-01

    Autism is diagnosed on the basis of a triad of impairments in social interaction, communication, and flexible imaginative functions (with restricted and repetitive behaviors and interests; RRBIs). There has been a strong presumption that these different features of the syndrome are strongly intertwined and proceed from a common cause at the genetic, cognitive and neural levels. In this review we examine evidence for an alternative approach, considering the triad as largely 'fractionable'. We present evidence from our own twin studies, and review relevant literature on autism and autistic-like traits in other groups. We suggest that largely independent genes may operate on social skills/impairments, communication abilities, and RRBIs, requiring a change in molecular-genetic research approaches. At the cognitive level, we suggest that satisfactory accounts exist for each of the triad domains, but no single unitary account can explain both social and nonsocial features of autism. We discuss the implications of the fractionable-triad approach for both diagnosis and future research directions.

  14. Neural dynamics of event segmentation in music: converging evidence for dissociable ventral and dorsal networks.

    Science.gov (United States)

    Sridharan, Devarajan; Levitin, Daniel J; Chafe, Chris H; Berger, Jonathan; Menon, Vinod

    2007-08-02

    The real world presents our sensory systems with a continuous stream of undifferentiated information. Segmentation of this stream at event boundaries is necessary for object identification and feature extraction. Here, we investigate the neural dynamics of event segmentation in entire musical symphonies under natural listening conditions. We isolated time-dependent sequences of brain responses in a 10 s window surrounding transitions between movements of symphonic works. A strikingly right-lateralized network of brain regions showed peak response during the movement transitions when, paradoxically, there was no physical stimulus. Model-dependent and model-free analysis techniques provided converging evidence for activity in two distinct functional networks at the movement transition: a ventral fronto-temporal network associated with detecting salient events, followed in time by a dorsal fronto-parietal network associated with maintaining attention and updating working memory. Our study provides direct experimental evidence for dissociable and causally linked ventral and dorsal networks during event segmentation of ecologically valid auditory stimuli.

  15. Central perception of position sense involves a distributed neural network - Evidence from lesion-behavior analyses.

    Science.gov (United States)

    Findlater, Sonja E; Desai, Jamsheed A; Semrau, Jennifer A; Kenzie, Jeffrey M; Rorden, Chris; Herter, Troy M; Scott, Stephen H; Dukelow, Sean P

    2016-06-01

    It is well established that proprioceptive inputs from the periphery are important for the constant update of arm position for perception and guiding motor action. The degree to which we are consciously aware of the position of our limb depends on the task. Our understanding of the central processing of position sense is rather limited, largely based on findings in animals and individual human case studies. The present study used statistical lesion-behavior analysis and an arm position matching task to investigate position sense in a large sample of subjects after acute stroke. We excluded subjects who performed abnormally on clinical testing or a robotic visually guided reaching task with their matching arm in order to minimize the potential confound of ipsilesional impairment. Our findings revealed that a number of regions are important for processing position sense and include the posterior parietal cortex, the transverse temporal gyrus, and the arcuate fasciculus. Further, our results revealed that position sense has dissociable components - spatial variability, perceived workspace area, and perceived workspace location. Each component is associated with unique neuroanatomical correlates. These findings extend the current understanding of the neural processing of position sense and identify some brain areas that are not classically associated with proprioception.

  16. A critical view of the use of genetic tools to unveil neural circuits: the case of leptin action in reproduction.

    Science.gov (United States)

    Elias, Carol F

    2014-01-01

    The remarkable development and refinement of the Cre-loxP system coupled with the nonstop production of new mouse models and virus vectors have impelled the growth of various fields of investigation. In this article, I will discuss the data collected using these genetic tools in our area of interest, giving specific emphasis to the identification of the neuronal populations that relay leptin action in reproductive physiology. A series of mouse models that allow manipulation of the leptin receptor gene have been generated. Of those, I will discuss the use of two models of leptin receptor gene reexpression (LepR(neo/neo) and LepR(loxTB/loxTB)) and one model of leptin signaling blockade (LepR(flox/flox)). I will also highlight the differences of using stereotaxic delivery of virus vectors expressing DNA-recombinases (Flp and Cre) and mouse models expressing Cre-recombinase. Our findings indicate that leptin action in the ventral premammillary nucleus is sufficient, but not required, for leptin action in reproduction and that leptin action in Kiss1 neurons arises after pubertal maturation; therefore, direct leptin signaling in Kiss1 neurons is neither required nor sufficient for the permissive action of leptin in pubertal development. It also became evident that the full action of leptin in the reproductive neuroendocrine axis requires the engagement of an integrated circuitry, yet to be fully unveiled.

  17. Predicting others' actions via grasp and gaze: evidence for distinct brain networks.

    Science.gov (United States)

    Ramsey, Richard; Cross, Emily S; Hamilton, Antonia F de C

    2012-07-01

    During social interactions, how do we predict what other people are going to do next? One view is that we use our own motor experience to simulate and predict other people's actions. For example, when we see Sally look at a coffee cup or grasp a hammer, our own motor system provides a signal that anticipates her next action. Previous research has typically examined such gaze and grasp-based simulation processes separately, and it is not known whether similar cognitive and brain systems underpin the perception of object-directed gaze and grasp. Here we use functional magnetic resonance imaging to examine to what extent gaze- and grasp-perception rely on common or distinct brain networks. Using a 'peeping window' protocol, we controlled what an observed actor could see and grasp. The actor could peep through one window to see if an object was present and reach through a different window to grasp the object. However, the actor could not peep and grasp at the same time. We compared gaze and grasp conditions where an object was present with matched conditions where the object was absent. When participants observed another person gaze at an object, left anterior inferior parietal lobule (aIPL) and parietal operculum showed a greater response than when the object was absent. In contrast, when participants observed the actor grasp an object, premotor, posterior parietal, fusiform and middle occipital brain regions showed a greater response than when the object was absent. These results point towards a division in the neural substrates for different types of motor simulation. We suggest that left aIPL and parietal operculum are involved in a predictive process that signals a future hand interaction with an object based on another person's eye gaze, whereas a broader set of brain areas, including parts of the action observation network, are engaged during observation of an ongoing object-directed hand action.

  18. The importance of actions and the worth of an object: dissociable neural systems representing core value and economic value.

    Science.gov (United States)

    Brosch, Tobias; Coppin, Géraldine; Schwartz, Sophie; Sander, David

    2012-06-01

    Neuroeconomic research has delineated neural regions involved in the computation of value, referring to a currency for concrete choices and decisions ('economic value'). Research in psychology and sociology, on the other hand, uses the term 'value' to describe motivational constructs that guide choices and behaviors across situations ('core value'). As a first step towards an integration of these literatures, we compared the neural regions computing economic value and core value. Replicating previous work, economic value computations activated a network centered on medial orbitofrontal cortex. Core value computations activated medial prefrontal cortex, a region involved in the processing of self-relevant information and dorsal striatum, involved in action selection. Core value ratings correlated with activity in precuneus and anterior prefrontal cortex, potentially reflecting the degree to which a core value is perceived as internalized part of one's self-concept. Distributed activation pattern in insula and ACC allowed differentiating individual core value types. These patterns may represent evaluation profiles reflecting prototypical fundamental concerns expressed in the core value types. Our findings suggest mechanisms by which core values, as motivationally important long-term goals anchored in the self-schema, may have the behavioral power to drive decisions and behaviors in the absence of immediately rewarding behavioral options.

  19. Evidence for dual mechanisms of action prediction dependent on acquired visual-motor experiences.

    Science.gov (United States)

    Mulligan, Desmond; Lohse, Keith R; Hodges, Nicola J

    2016-10-01

    To test mechanisms underpinning action prediction, we directly controlled experience in a dart-throwing training study. A motor-visual group physically practiced throwing darts and a perceptual training group learned to associate dart throw actions (occluded video clips) with landing outcomes. A final control group did not practice. Accuracy was assessed on related prediction tests before and after practice (involving temporally occluded video clips). These tests were performed while additionally performing simple, action-incongruent secondary motor tasks with either the right (observed throwing arm) or left effector, in addition to an attention control task. Motor proficiency tests were also performed. Although both trained groups improved their prediction accuracy after training, only the motor-visual group showed interference associated with the right-arm secondary motor task after practice. No interference was shown for the left-arm motor task. These effects were evidenced regardless of whether predictions were made in response to video stimuli or static clips. Moreover, improvements on the motor proficiency test were only shown for the motor-visual group. These results show evidence in support of motor simulation processes during action prediction among observers with motor experience. Prediction accuracy can be achieved via nonmotor processes (for the perceptual group), but there was no evidence that physically experienced performers could effectively switch processes to maintain prediction accuracy. (PsycINFO Database Record

  20. Evidence-based modeling of mode-of-action for functional ingredients influencing Alzheimer’s disease through neurotrophin pathway

    Directory of Open Access Journals (Sweden)

    Erfan Younesi

    2014-08-01

    Full Text Available Background: Brain-derived neurotrophic factor (BDNF is the most widely expressed member of the neurotrophin family in the human brain and is crucially involved in the development of neural circuits, modulation of synaptic plasticity, and regulation of cognitive functions, including learning and memory. Many studies have shown the association of altered BDNF levels with neurodegenerative and neuropsychiatric disorders. However, BDNF is not able to cross the blood-brain barrier and, thus, its delivery to the nervous system is a challenge. Therefore, functional diets with the ability to induce production of BDNF in the brain may offer an alternative route. The objective of this study was three-fold: first, to find out diets that are causally linked to the agonistic activity of BDNF in the neurotrophin signaling pathway; second and mainly, to investigate mode-of-action of these functional diets through systems-based mechanistic modeling in the context of Alzheimer’s disease; and third, to demonstrate the proof-of-concept application of systems biology methods, that are well established in the pharmaceutical sector, to the emerging field of functional food. Methods: In the first step, two cause-and-effect models of BDNF signaling in two states, i.e. normal state and Alzheimer’s disease state, were constructed using published knowledge in scientific literature and pathway databases. A “differential model analysis” between the two states was performed by which mechanistic mode-of-action of BDNF in neurotrophin signaling pathway could be explained with a high molecular resolution in both normal and disease states. The BDNF mode-of-action model was further validated using the “biomarkerguided validation” approach. In the second step, scientific evidence on the effect of various functional diets on BDNF levels and BDNF-related biological processes or outcomes was harvested from biomedical literature using a disease-specific semantic search

  1. Why Don't We Move Slower? The Value of Time in the Neural Control of Action.

    Science.gov (United States)

    Berret, Bastien; Jean, Frédéric

    2016-01-27

    To want something now rather than later is a common attitude that reflects the brain's tendency to value the passage of time. Because the time taken to accomplish an action inevitably delays task achievement and reward acquisition, this idea was ported to neural movement control within the "cost of time" theory. This theory provides a normative framework to account for the underpinnings of movement time formation within the brain and the origin of a self-selected pace in human and animal motion. Then, how does the brain exactly value time in the control of action? To tackle this issue, we used an inverse optimal control approach and developed a general methodology allowing to squarely sample infinitesimal values of the time cost from experimental motion data. The cost of time underlying saccades was found to have a concave growth, thereby confirming previous results on hyperbolic reward discounting, yet without making any prior assumption about this hypothetical nature. For self-paced reaching, however, movement time was primarily valued according to a striking sigmoidal shape; its rate of change consistently presented a steep rise before a maximum was reached and a slower decay was observed. Theoretical properties of uniqueness and robustness of the inferred time cost were established for the class of problems under investigation, thus reinforcing the significance of the present findings. These results may offer a unique opportunity to uncover how the brain values the passage of time in healthy and pathological motor control and shed new light on the processes underlying action invigoration. Movement time is a fundamental characteristic of neural motor control, but the principles underlying its formation remain little known. This work addresses that question within the inverse optimal control framework where the challenge is to uncover what optimality criterion underlies a system's behavior. Here we rely on the "cost of time" theory that finds its roots into the

  2. Neural and behavioral correlates of selective stopping: Evidence for a different strategy adoption.

    Science.gov (United States)

    Sánchez-Carmona, Alberto J; Albert, Jacobo; Hinojosa, José A

    2016-10-01

    The present study examined the neural and behavioral correlates of selective stopping, a form of inhibition that has scarcely been investigated. The selectivity of the inhibitory process is needed when individuals have to deal with an environment filled with multiple stimuli, some of which require inhibition and some of which do not. The stimulus-selective stop-signal task has been used to explore this issue assuming that all participants interrupt their ongoing responses selectively to stop but not to ignore signals. However, recent behavioral evidence suggests that some individuals do not carry out the task as experimenters expect, since they seemed to interrupt their response non-selectively to both signals. In the present study, we detected and controlled the cognitive strategy adopted by participants (n=57) when they performed a stimulus-selective stop-signal task before comparing brain activation between conditions. In order to determine both the onset and the end of the response cancellation process underlying each strategy and to fully take advantage of the precise temporal resolution of event-related potentials, we used a mass univariate approach. Source localization techniques were also employed to estimate the neural underpinnings of the effects observed at the scalp level. Our results from scalp and source level analysis support the behavioral-based strategy classification. Specific effects were observed depending on the strategy adopted by participants. Thus, when contrasting successful stop versus ignore conditions, increased activation was only evident for subjects who were classified as using a strategy whereby the response interruption process was selective to stop trials. This increased activity was observed during the P3 time window in several left-lateralized brain regions, including middle and inferior frontal gyri, as well as parietal and insular cortices. By contrast, in those participants who used a strategy characterized by stopping non

  3. Youth Excel: towards a pan-Canadian platform linking evidence and action for prevention.

    Science.gov (United States)

    Riley, Barbara L; Manske, Steve; Cameron, Roy

    2011-05-15

    Population-level intervention is required to prevent cancer and other chronic diseases. It also promotes health for those living with established risk factors and illness. In this article, the authors describe a vision and approach for continuously improving population-level programs and policies within and beyond the health sector. The vision and approach are anchored in contemporary thinking about what is required to link evidence and action in the field of population and public health. The authors believe that, as a cancer prevention and control community, organizations and practitioners must be able to use the best available evidence to inform action and continually generate evidence that improves prevention policies and programs on an ongoing basis. These imperatives require leaders in policy, practice, and research fields to work together to jointly plan, conduct, and act on relevant evidence. The Propel Center and colleagues are implementing this approach in Youth Excel-a pan-Canadian initiative that brings together national and provincial organizations from health and education sectors and capitalizes on a history of collaboration. The objective of Youth Excel is to build sustainable capacity for knowledge development and exchange that can guide and redirect prevention efforts in a rapidly evolving social environment. This goal is to contribute to creating health-promoting environments and to accelerate progress in preventing cancer and other diseases among youth and young adults and in the wider population. Although prevention is the aim, health-promoting environments also can support health gains for individuals of all ages and with established illness. In addition, the approach Youth Excel is taking to link evidence and action may be applicable to early intervention and treatment components of cancer control.

  4. Linking perception, cognition, and action: psychophysical observations and neural network modelling.

    Directory of Open Access Journals (Sweden)

    Juan Carlos Méndez

    Full Text Available It has been argued that perception, decision making, and movement planning are in reality tightly interwoven brain processes. However, how they are implemented in neural circuits is still a matter of debate. We tested human subjects in a temporal categorization task in which intervals had to be categorized as short or long. Subjects communicated their decision by moving a cursor into one of two possible targets, which appeared separated by different angles from trial to trial. Even though there was a 1 second-long delay between interval presentation and decision communication, categorization difficulty affected subjects' performance, reaction (RT and movement time (MT. In addition, reaction and movement times were also influenced by the distance between the targets. This implies that not only perceptual, but also movement-related considerations were incorporated into the decision process. Therefore, we searched for a model that could use categorization difficulty and target separation to describe subjects' performance, RT, and MT. We developed a network consisting of two mutually inhibiting neural populations, each tuned to one of the possible categories and composed of an accumulation and a memory node. This network sequentially acquired interval information, maintained it in working memory and was then attracted to one of two possible states, corresponding to a categorical decision. It faithfully replicated subjects' RT and MT as a function of categorization difficulty and target distance; it also replicated performance as a function of categorization difficulty. Furthermore, this model was used to make new predictions about the effect of untested durations, target distances and delay durations. To our knowledge, this is the first biologically plausible model that has been proposed to account for decision making and communication by integrating both sensory and motor planning information.

  5. Complex Dynamic Thresholds and Generation of the Action Potentials in the Neural-Activity Model

    Science.gov (United States)

    Kirillov, S. Yu.; Nekorkin, V. I.

    2016-05-01

    This work is devoted to studying the processes of activation of the neurons whose excitation thresholds are not constant and vary in time (the so-called dynamic thresholds). The neuron dynamics is described by the FitzHugh-Nagumo model with nonlinear behavior of the recovery variable. The neuron response to the external pulsed activating action in the presence of a slowly varying synaptic current is studied within the framework of this model. The structure of the dynamic threshold is studied and its properties depending on the external-action parameters are established. It is found that the formation of the "folds" in the separatrix threshold manifold in the model phase space is a typical feature of the complex dynamic threshold. High neuron sensitivity to the action of the comparatively weak slow control signals is established. This explains the capability of the neurons to perform flexible tuning of their selective properties for detecting various external signals in sufficiently short times (of the order of duration of several spikes).

  6. Normative findings of electrically evoked compound action potential measurements using the neural response telemetry of the Nucleus CI24M cochlear implant system.

    NARCIS (Netherlands)

    Cafarelli-Dees, D.; Dillier, N.; Lai, W.K.; Wallenberg, E. von; Dijk, B. van; Akdas, F.; Aksit, M.; Batman, C.; Beynon, A.J.; Burdo, S.; Chanal, J.M.; Collet, L.; Conway, M.; Coudert, C.; Craddock, L.; Cullington, H.; Deggouj, N.; Fraysse, B.; Grabel, S.; Kiefer, J.; Kiss, J.G.; Lenarz, T.; Mair, A.; Maune, S.; Muller-Deile, J.; Piron, J.P.; Razza, S.; Tasche, C.; Thai-Van, H.; Toth, F.; Truy, E.; Uziel, A.; Smoorenburg, G.F.

    2005-01-01

    One hundred and forty-seven adult recipients of the Nucleus 24 cochlear implant system, from 13 different European countries, were tested using neural response telemetry to measure the electrically evoked compound action potential (ECAP), according to a standardised postoperative measurement procedu

  7. Heritability of the neural response to emotional pictures: evidence from ERPs in an adult twin sample.

    Science.gov (United States)

    Weinberg, Anna; Venables, Noah C; Proudfit, Greg Hajcak; Patrick, Christopher J

    2015-03-01

    Affect-modulated event-related potentials (ERPs) are increasingly used to study psychopathology and individual differences in emotion processing. Many have suggested that variation in these neural responses reflects genetically mediated risk. However, to date, no studies have demonstrated genetic contributions to affect-modulated ERPs. The present study therefore sought to examine the heritability of a range of ERPs elicited during affective picture viewing. One hundred and thirty monozygotic and 124 dizygotic twin pairs passively viewed 30 pleasant, 30 neutral and 30 unpleasant images for 6 s each. The early posterior negativity was scored for each subject; in addition, the P300/late positive potential (LPP) was scored in multiple time windows and sites. Results indicate that the centro-parietal P300 (occurring between 300 and 600 ms) is subject to substantial genetic contributions. Furthermore, variance in the P300 elicited by affective stimuli was moderately heritable even after controlling for the P300 elicited by neutral stimuli. Later and more frontal activation (i.e. between 1000 and 3000 ms) also showed evidence of heritablity. Early parietal, and perhaps later frontal portions of the P300/LPP complex, may therefore represent promising neurobehavioral markers of genetically influenced processing of emotional information. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  8. Musical experience facilitates lexical tone processing among Mandarin speakers: Behavioral and neural evidence.

    Science.gov (United States)

    Tang, Wei; Xiong, Wen; Zhang, Yu-Xuan; Dong, Qi; Nan, Yun

    2016-10-01

    Music and speech share many sound attributes. Pitch, as the percept of fundamental frequency, often occupies the center of researchers' attention in studies on the relationship between music and speech. One widely held assumption is that music experience may confer an advantage in speech tone processing. The cross-domain effects of musical training on non-tonal language speakers' linguistic pitch processing have been relatively well established. However, it remains unclear whether musical experience improves the processing of lexical tone for native tone language speakers who actually use lexical tones in their daily communication. Using a passive oddball paradigm, the present study revealed that among Mandarin speakers, musicians demonstrated enlarged electrical responses to lexical tone changes as reflected by the increased mismatch negativity (MMN) amplitudes, as well as faster behavioral discrimination performance compared with age- and IQ-matched nonmusicians. The current results suggest that in spite of the preexisting long-term experience with lexical tones in both musicians and nonmusicians, musical experience can still modulate the cortical plasticity of linguistic tone processing and is associated with enhanced neural processing of speech tones. Our current results thus provide the first electrophysiological evidence supporting the notion that pitch expertise in the music domain may indeed be transferable to the speech domain even for native tone language speakers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Neural Correlates of Indicators of Sound Change in Cantonese: Evidence from Cortical and Subcortical Processes

    Science.gov (United States)

    Maggu, Akshay R.; Liu, Fang; Antoniou, Mark; Wong, Patrick C. M.

    2016-01-01

    Across time, languages undergo changes in phonetic, syntactic, and semantic dimensions. Social, cognitive, and cultural factors contribute to sound change, a phenomenon in which the phonetics of a language undergo changes over time. Individuals who misperceive and produce speech in a slightly divergent manner (called innovators) contribute to variability in the society, eventually leading to sound change. However, the cause of variability in these individuals is still unknown. In this study, we examined whether such misperceptions are represented in neural processes of the auditory system. We investigated behavioral, subcortical (via FFR), and cortical (via P300) manifestations of sound change processing in Cantonese, a Chinese language in which several lexical tones are merging. Across the merging categories, we observed a similar gradation of speech perception abilities in both behavior and the brain (subcortical and cortical processes). Further, we also found that behavioral evidence of tone merging correlated with subjects' encoding at the subcortical and cortical levels. These findings indicate that tone-merger categories, that are indicators of sound change in Cantonese, are represented neurophysiologically with high fidelity. Using our results, we speculate that innovators encode speech in a slightly deviant neurophysiological manner, and thus produce speech divergently that eventually spreads across the community and contributes to sound change. PMID:28066218

  10. Neural mechanisms underlying pain's ability to reorient attention: evidence for sensitization of somatic threat detectors.

    Science.gov (United States)

    Dowman, Robert

    2014-06-01

    Pain typically signals damage to the body, and as such can be perceived as threatening and can elicit a strong emotional response. This ecological significance undoubtedly underlies pain's well-known ability to demand attention. However, the neural mechanisms underlying this ability are poorly understood. Previous work from the author's laboratory has reported behavioral evidence suggesting that participants disengage their attention from an incorrectly cued visual target stimulus and reorient it toward a somatic target more rapidly when the somatic target is painful than when it is nonpainful. Furthermore, electrophysiological data suggest that this effect is mediated by a stimulus-driven process, in which somatic threat detectors located in the dorsal posterior insula activate the medial and lateral prefrontal cortex areas involved in reorienting attention toward the painful target. In these previous studies, the painful and nonpainful somatic targets were given in separate experiments involving different participants. Here, the nonpainful and painful somatic targets were presented in random order within the same block of trials. Unlike in the previous studies, both the nonpainful and painful somatic targets activated the somatic threat detectors, and the times taken to disengage and reorient attention were the same for both. These electrophysiological and behavioral data suggest that somatic threat detectors can become sensitized to nonpainful somatic stimuli that are presented in a context that includes painful stimuli.

  11. Cross-Modal Decoding of Neural Patterns Associated with Working Memory: Evidence for Attention-Based Accounts of Working Memory.

    Science.gov (United States)

    Majerus, Steve; Cowan, Nelson; Péters, Frédéric; Van Calster, Laurens; Phillips, Christophe; Schrouff, Jessica

    2016-01-01

    Recent studies suggest common neural substrates involved in verbal and visual working memory (WM), interpreted as reflecting shared attention-based, short-term retention mechanisms. We used a machine-learning approach to determine more directly the extent to which common neural patterns characterize retention in verbal WM and visual WM. Verbal WM was assessed via a standard delayed probe recognition task for letter sequences of variable length. Visual WM was assessed via a visual array WM task involving the maintenance of variable amounts of visual information in the focus of attention. We trained a classifier to distinguish neural activation patterns associated with high- and low-visual WM load and tested the ability of this classifier to predict verbal WM load (high-low) from their associated neural activation patterns, and vice versa. We observed significant between-task prediction of load effects during WM maintenance, in posterior parietal and superior frontal regions of the dorsal attention network; in contrast, between-task prediction in sensory processing cortices was restricted to the encoding stage. Furthermore, between-task prediction of load effects was strongest in those participants presenting the highest capacity for the visual WM task. This study provides novel evidence for common, attention-based neural patterns supporting verbal and visual WM. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Neural network evidence for the coupling of presaccadic visual remapping to predictive eye position updating

    Directory of Open Access Journals (Sweden)

    Hrishikesh M Rao

    2016-06-01

    Full Text Available As we look around a scene, we perceive it as continuous and stable even though each saccadic eye movement changes the visual input to the retinas. How the brain achieves this perceptual stabilization is unknown, but a major hypothesis is that it relies on presaccadic remapping, a process in which neurons shift their visual sensitivity to a new location in the scene just before each saccade. This hypothesis is difficult to test in vivo because complete, selective inactivation of remapping is currently intractable. We tested it in silico with a hierarchical, sheet-based neural network model of the visual and oculomotor system. The model generated saccadic commands to move a video camera abruptly. Visual input from the camera and internal copies of the saccadic movement commands, or corollary discharge, converged at a map-level simulation of the frontal eye field (FEF, a primate brain area known to receive such inputs. FEF output was combined with eye position signals to yield a suitable coordinate frame for guiding arm movements of a robot. Our operational definition of perceptual stability was useful stability, quantified as continuously accurate pointing to a visual object despite camera saccades. During training, the emergence of useful stability was correlated tightly with the emergence of presaccadic remapping in the FEF. Remapping depended on corollary discharge but its timing was synchronized to the updating of eye position. When coupled to predictive eye position signals, remapping served to stabilize the target representation for continuously accurate pointing. Graded inactivations of pathways in the model replicated, and helped to interpret, previous in vivo experiments. The results support the hypothesis that visual stability requires presaccadic remapping, provide explanations for the function and timing of remapping, and offer testable hypotheses for in vivo studies. We conclude that remapping allows for seamless coordinate frame

  13. Transferability of Training Benefits Differs across Neural Events: Evidence from ERPs.

    Science.gov (United States)

    Garner, Kelly G; Matthews, Natasha; Remington, Roger W; Dux, Paul E

    2015-10-01

    Humans can show striking capacity limitations in sensorimotor processing. Fortunately, these limitations can be attenuated with training. However, less fortunately, training benefits often remain limited to trained tasks. Recent behavioral observations suggest that the extent to which training transfers may depend on the specific stage of information processing that is being executed. Training benefits for a task that taps the consolidation of sensory information (sensory encoding) transfer to new stimulus-response mappings, whereas benefits for selecting an appropriate action (decision-making/response selection) remain specific to the trained mappings. Therefore, training may have dissociable influences on the neural events underlying subsequent sensorimotor processing stages. Here, we used EEG to investigate this possibility. In a pretraining baseline session, participants completed two four-alternative-choice response time tasks, presented both as a single task and as part of a dual task (with another task). The training group completed a further 3,000 training trials on one of the four-alternative-choice tasks. Hence, one task became trained, whereas the other remained untrained. At test, a negative-going component that is sensitive to sensory-encoding demands (N2) showed increased amplitudes and reduced latencies for trained and untrained mappings relative to a no-train control group. In contrast, the onset of the stimulus-locked lateralized readiness potential, a component that reflects the activation of motor plans, was reduced only for tasks that employed trained stimulus-response mappings, relative to untrained stimulus-response mappings and controls. Collectively, these results show that training benefits are dissociable for the brain events that reflect distinct sensorimotor processing stages.

  14. The method of educational assessment affects children's neural processing and performance: behavioural and fMRI Evidence

    Science.gov (United States)

    Howard, Steven J.; Burianová, Hana; Calleia, Alysha; Fynes-Clinton, Samuel; Kervin, Lisa; Bokosmaty, Sahar

    2017-08-01

    Standardised educational assessments are now widespread, yet their development has given comparatively more consideration to what to assess than how to optimally assess students' competencies. Existing evidence from behavioural studies with children and neuroscience studies with adults suggest that the method of assessment may affect neural processing and performance, but current evidence remains limited. To investigate the impact of assessment methods on neural processing and performance in young children, we used functional magnetic resonance imaging to identify and quantify the neural correlates during performance across a range of current approaches to standardised spelling assessment. Results indicated that children's test performance declined as the cognitive load of assessment method increased. Activation of neural nodes associated with working memory further suggests that this performance decline may be a consequence of a higher cognitive load, rather than the complexity of the content. These findings provide insights into principles of assessment (re)design, to ensure assessment results are an accurate reflection of students' true levels of competency.

  15. Interactive actions of Bdnf methylation and cell metabolism for building neural resilience under the influence of diet.

    Science.gov (United States)

    Tyagi, Ethika; Zhuang, Yumei; Agrawal, Rahul; Ying, Zhe; Gomez-Pinilla, Fernando

    2015-01-01

    Quality nutrition during the period of brain formation is a predictor of brain functional capacity and plasticity during adulthood; however it is not clear how this conferred plasticity imparts long-term neural resilience. Here we report that early exposure to dietary omega-3 fatty acids orchestrates key interactions between metabolic signals and Bdnf methylation creating a reservoir of neuroplasticity that can protect the brain against the deleterious effects of switching to a Western diet (WD). We observed that the switch to a WD increased Bdnf methylation specific to exon IV, in proportion to anxiety-like behavior, in Sprague Dawley rats reared in low omega-3 fatty acid diet, and these effects were abolished by the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine. Blocking methylation also counteracted the reducing action of WD on the transcription regulator CTCF binding to Bdnf promoter IV. In vitro studies confirmed that CTCF binding to Bdnf promoter IV is essential for the action of DHA on BDNF regulation. Diet is also intrinsically associated to cell metabolism, and here we show that the switch to WD downregulated cell metabolism (NAD/NADH ratio and SIRT1). The fact that DNA methyltransferase inhibitor did not alter these parameters suggests they occur upstream to methylation. In turn, the methylation inhibitor counteracted the action of WD on PGC-1α, a mitochondrial transcription co-activator and BDNF regulator, suggesting that PGC-1α is an effector of Bdnf methylation. Results support a model in which diet can build an "epigenetic memory" during brain formation that confers resilience to metabolic perturbations occurring in adulthood.

  16. From damage response to action potentials: early evolution of neural and contractile modules in stem eukaryotes.

    Science.gov (United States)

    Brunet, Thibaut; Arendt, Detlev

    2016-01-05

    Eukaryotic cells convert external stimuli into membrane depolarization, which in turn triggers effector responses such as secretion and contraction. Here, we put forward an evolutionary hypothesis for the origin of the depolarization-contraction-secretion (DCS) coupling, the functional core of animal neuromuscular circuits. We propose that DCS coupling evolved in unicellular stem eukaryotes as part of an 'emergency response' to calcium influx upon membrane rupture. We detail how this initial response was subsequently modified into an ancient mechanosensory-effector arc, present in the last eukaryotic common ancestor, which enabled contractile amoeboid movement that is widespread in extant eukaryotes. Elaborating on calcium-triggered membrane depolarization, we reason that the first action potentials evolved alongside the membrane of sensory-motile cilia, with the first voltage-sensitive sodium/calcium channels (Nav/Cav) enabling a fast and coordinated response of the entire cilium to mechanosensory stimuli. From the cilium, action potentials then spread across the entire cell, enabling global cellular responses such as concerted contraction in several independent eukaryote lineages. In animals, this process led to the invention of mechanosensory contractile cells. These gave rise to mechanosensory receptor cells, neurons and muscle cells by division of labour and can be regarded as the founder cell type of the nervous system. © 2015 The Authors.

  17. Exploring the neural correlates of goal-directed action and intention understanding.

    Science.gov (United States)

    Carter, Elizabeth J; Hodgins, Jessica K; Rakison, David H

    2011-01-15

    Because we are a cooperative species, understanding the goals and intentions of others is critical for human survival. In this fMRI study, participants viewed reaching behaviors in which one of four animated characters moved a hand towards one of two objects and either (a) picked up the object, (b) missed the object, or (c) changed his path halfway to lift the other object. The characters included a human, a humanoid robot, stacked boxes with an arm, and a mechanical claw. The first three moved in an identical, human-like biological pattern. Right posterior superior temporal sulcus (pSTS) activity increased when the human or humanoid robot shifted goals or missed the target relative to obtaining the original goal. This suggests that the pSTS was engaged differentially for figures that appeared more human-like rather than for all human-like motion. Medial frontal areas that are part of a protagonist-monitoring network with the right pSTS (e.g., Mason and Just, 2006) were most engaged for the human character, followed by the robot character. The current data suggest that goal-directed action and intention understanding require this network and it is used similarly for the two processes. Moreover, it is modulated by character identity rather than only the presence of biological motion. We discuss the implications for behavioral theories of goal-directed action and intention understanding.

  18. AKT signaling mediates IGF-I survival actions on otic neural progenitors.

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    Maria R Aburto

    Full Text Available BACKGROUND: Otic neurons and sensory cells derive from common progenitors whose transition into mature cells requires the coordination of cell survival, proliferation and differentiation programmes. Neurotrophic support and survival of post-mitotic otic neurons have been intensively studied, but the bases underlying the regulation of programmed cell death in immature proliferative otic neuroblasts remains poorly understood. The protein kinase AKT acts as a node, playing a critical role in controlling cell survival and cell cycle progression. AKT is activated by trophic factors, including insulin-like growth factor I (IGF-I, through the generation of the lipidic second messenger phosphatidylinositol 3-phosphate by phosphatidylinositol 3-kinase (PI3K. Here we have investigated the role of IGF-dependent activation of the PI3K-AKT pathway in maintenance of otic neuroblasts. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of organotypic cultures of chicken (Gallus gallus otic vesicles and acoustic-vestibular ganglia, Western blotting, immunohistochemistry and in situ hybridization, we show that IGF-I-activation of AKT protects neural progenitors from programmed cell death. IGF-I maintains otic neuroblasts in an undifferentiated and proliferative state, which is characterised by the upregulation of the forkhead box M1 (FoxM1 transcription factor. By contrast, our results indicate that post-mitotic p27(Kip-positive neurons become IGF-I independent as they extend their neuronal processes. Neurons gradually reduce their expression of the Igf1r, while they increase that of the neurotrophin receptor, TrkC. CONCLUSIONS/SIGNIFICANCE: Proliferative otic neuroblasts are dependent on the activation of the PI3K-AKT pathway by IGF-I for survival during the otic neuronal progenitor phase of early inner ear development.

  19. Physiological modules for generating discrete and rhythmic movements: action identification by a dynamic recurrent neural network.

    Directory of Open Access Journals (Sweden)

    Ana eBengoetxea

    2014-09-01

    Full Text Available In this study we employed a dynamic recurrent neural network (DRNN in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane and sagittal plane. We then trained a DRNN to predict the movement of the wrist from information in the EMG signals from seven different muscles. We trained different instances of the same network on a single movement direction, on all four movement directions in a single movement plane, or on all eight possible movement patterns and looked at the ability of the DRNN to generalize and predict movements for trials that were not included in the training set. Within a single movement plane, a DRNN trained on one movement direction was not able to predict movements of the hand for trials in the other three directions, but a DRNN trained simultaneously on all four movement directions could generalize across movement directions within the same plane. Similarly, the DRNN was able to reproduce the kinematics of the hand for both movement planes, but only if it was trained on examples performed in each one. As we will discuss, these results indicate that there are important dynamical constraints on the mapping of EMG to hand movement that depend on both the time sequence of the movement and on the anatomical constraints of the musculoskeletal system. In a second step, we injected EMG signals constructed from different synergies derived by the PCA in order to identify the mechanical significance of each of these components. From these results, one can surmise that discrete-rhythmic movements may be constructed from three different fundamental modules, one regulating the co-activation of all muscles over the time span of the movement and two others patterns of reciprocal activation operating in orthogonal

  20. Physiological modules for generating discrete and rhythmic movements: action identification by a dynamic recurrent neural network.

    Science.gov (United States)

    Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana M; Dan, Bernard; McIntyre, Joseph; Cheron, Guy

    2014-01-01

    In this study we employed a dynamic recurrent neural network (DRNN) in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane and sagittal plane). We then trained a DRNN to predict the movement of the wrist from information in the EMG signals from seven different muscles. We trained different instances of the same network on a single movement direction, on all four movement directions in a single movement plane, or on all eight possible movement patterns and looked at the ability of the DRNN to generalize and predict movements for trials that were not included in the training set. Within a single movement plane, a DRNN trained on one movement direction was not able to predict movements of the hand for trials in the other three directions, but a DRNN trained simultaneously on all four movement directions could generalize across movement directions within the same plane. Similarly, the DRNN was able to reproduce the kinematics of the hand for both movement planes, but only if it was trained on examples performed in each one. As we will discuss, these results indicate that there are important dynamical constraints on the mapping of EMG to hand movement that depend on both the time sequence of the movement and on the anatomical constraints of the musculoskeletal system. In a second step, we injected EMG signals constructed from different synergies derived by the PCA in order to identify the mechanical significance of each of these components. From these results, one can surmise that discrete-rhythmic movements may be constructed from three different fundamental modules, one regulating the co-activation of all muscles over the time span of the movement and two others elliciting patterns of reciprocal activation operating in orthogonal directions.

  1. 涡虫神经再生的分子机制%Molecular actions guiding neural regeneration in planarian

    Institute of Scientific and Technical Information of China (English)

    张燕芬; 叶波平; 王大勇

    2008-01-01

    Planarian is among the simplest animals that possess a centralized nervous system (CNS),and its neural regeneration involves the replacement of cells lost to normal 'wear and tear' (cell turnover),and/or injury.In this review,we state and discuss the recent studies on molecular control of neural regeneration in planarians.The spatial and temporal expression patterns of genes in intact and regenerating planarian CNS have already been described relatively clearly.The bone morphogenetic protein (BMP) and Writ signaling pathways are identified to regulate neural regeneration.During neural regeneration,conserved axon guidance mechanisms are necessary for proper wiring of the nervous system.In addition,apoptosis may play an important role in controlling cell numbers,eliminating unnecessary tissues or cells and remodeling the old tissues for regenerating CNS.The bilateral symmetry is established by determination of anterior-posterior (A-P) and dorsal-ventral (D-V) patterns.Moreover,neurons positive to dopamine,serotonin (5-HT),and gamma-aminobutyric acid (GABA) have been detected in planarians.Therefore,planarians present us with new,experimentally accessible contexts to study the molecular actions guiding neural regeneration.%涡虫是具有简单中枢神经系统的模式动物之一,其神经再生过程包括受损细胞的替换以及细胞的再生过程.本文阐述并讨论了近年来利用涡虫进行神经再生研究取得的研究进展.目前,参与涡虫神经再生相关基因的时空间表达图谱己被相对清晰地勾勒出来.骨形成蛋白和Wnt信号通路已被鉴定参与神经再生的调控.在神经再生过程中,保守的轴突导向机制为神经系统网络的正确形成所必需.此外,细胞凋亡在控制细胞数量、消除多余组织和细胞以及重新塑造再生的神经系统中发挥着重要作用.而且,在涡虫中多巴胺能神经元、五羟色胺能神经元和γ-氨基丁酸能神经元可以被有效地予以标

  2. Evidence for an immune-dependent action of praziquantel on Schistosoma mansoni in mice.

    Science.gov (United States)

    Doenhoff, M J; Sabah, A A; Fletcher, C; Webbe, G; Bain, J

    1987-01-01

    Effective schistosomicidal action of praziquantel against Schistosoma mansoni infections in mice appears to be dependent to some extent on appropriate immunological stimulation. Indirect evidence consistent with this hypothesis was obtained by demonstrating a positive relationship between drug efficacy and both the intensity and the age of the parasitic infection. More directly, it has previously been shown that praziquantel kills fewer S. mansoni worms in immunosuppressed T cell-deprived mice than in immunologically intact controls; and we show here that infections 5 weeks old, against which the drug alone is sub-optimally active, are more effectively killed by a combination of drug and a rabbit antiserum raised against adult worm antigens.

  3. A virtual reality-based system integrated with fmri to study neural mechanisms of action observation-execution: a proof of concept study.

    Science.gov (United States)

    Adamovich, S V; August, K; Merians, A; Tunik, E

    2009-01-01

    Emerging evidence shows that interactive virtual environments (VEs) may be a promising tool for studying sensorimotor processes and for rehabilitation. However, the potential of VEs to recruit action observation-execution neural networks is largely unknown. For the first time, a functional MRI-compatible virtual reality system (VR) has been developed to provide a window into studying brain-behavior interactions. This system is capable of measuring the complex span of hand-finger movements and simultaneously streaming this kinematic data to control the motion of representations of human hands in virtual reality. In a blocked fMRI design, thirteen healthy subjects observed, with the intent to imitate (OTI), finger sequences performed by the virtual hand avatar seen in 1st person perspective and animated by pre-recorded kinematic data. Following this, subjects imitated the observed sequence while viewing the virtual hand avatar animated by their own movement in real-time. These blocks were interleaved with rest periods during which subjects viewed static virtual hand avatars and control trials in which the avatars were replaced with moving non-anthropomorphic objects. We show three main findings. First, both observation with intent to imitate and imitation with real-time virtual avatar feedback, were associated with activation in a distributed frontoparietal network typically recruited for observation and execution of real-world actions. Second, we noted a time-variant increase in activation in the left insular cortex for observation with intent to imitate actions performed by the virtual avatar. Third, imitation with virtual avatar feedback (relative to the control condition) was associated with a localized recruitment of the angular gyrus, precuneus, and extrastriate body area, regions which are (along with insular cortex) associated with the sense of agency. Our data suggest that the virtual hand avatars may have served as disembodied training tools in the

  4. Intelligence moderates reinforcement learning: a mini-review of the neural evidence.

    Science.gov (United States)

    Chen, Chong

    2015-06-01

    Our understanding of the neural basis of reinforcement learning and intelligence, two key factors contributing to human strivings, has progressed significantly recently. However, the overlap of these two lines of research, namely, how intelligence affects neural responses during reinforcement learning, remains uninvestigated. A mini-review of three existing studies suggests that higher IQ (especially fluid IQ) may enhance the neural signal of positive prediction error in dorsolateral prefrontal cortex, dorsal anterior cingulate cortex, and striatum, several brain substrates of reinforcement learning or intelligence.

  5. Evidence for a Sex-Dependent MAOA× Childhood Stress Interaction in the Neural Circuitry of Aggression.

    Science.gov (United States)

    Holz, Nathalie; Boecker, Regina; Buchmann, Arlette F; Blomeyer, Dorothea; Baumeister, Sarah; Hohmann, Sarah; Jennen-Steinmetz, Christine; Wolf, Isabella; Rietschel, Marcella; Witt, Stephanie H; Plichta, Michael M; Meyer-Lindenberg, Andreas; Schmidt, Martin H; Esser, Günter; Banaschewski, Tobias; Brandeis, Daniel; Laucht, Manfred

    2016-03-01

    Converging evidence emphasizes the role of an interaction between monoamine oxidase A (MAOA) genotype, environmental adversity, and sex in the pathophysiology of aggression. The present study aimed to clarify the impact of this interaction on neural activity in aggression-related brain systems. Functional magnetic resonance imaging was performed in 125 healthy adults from a high-risk community sample followed since birth. DNA was genotyped for the MAOA-VNTR (variable number of tandem repeats). Exposure to childhood life stress (CLS) between the ages of 4 and 11 years was assessed using a standardized parent interview, aggression by the Youth/Young Adult Self-Report between the ages of 15 and 25 years, and the VIRA-R (Vragenlijst Instrumentele En Reactieve Agressie) at the age of 15 years. Significant interactions were obtained between MAOA genotype, CLS, and sex relating to amygdala, hippocampus, and anterior cingulate cortex (ACC) response, respectively. Activity in the amygdala and hippocampus during emotional face-matching increased with the level of CLS in male MAOA-L, while decreasing in male MAOA-H, with the reverse pattern present in females. Findings in the opposite direction in the ACC during a flanker NoGo task suggested that increased emotional activity coincided with decreased inhibitory control. Moreover, increasing amygdala activity was associated with higher Y(A)SR aggression in male MAOA-L and female MAOA-H carriers. Likewise, a significant association between amygdala activity and reactive aggression was detected in female MAOA-H carriers. The results point to a moderating role of sex in the MAOA× CLS interaction for intermediate phenotypes of emotional and inhibitory processing, suggesting a possible mechanism in conferring susceptibility to violence-related disorders.

  6. The neural basis of semantic cognition: converging evidence from neuropsychology, neuroimaging and TMS.

    Science.gov (United States)

    Jefferies, Elizabeth

    2013-03-01

    Recent studies suggest that a complex, distributed neural network underpins semantic cognition. This article reviews our contribution to this emerging picture and traces the putative roles of each region within this network. Neuropsychological studies indicate that semantic cognition draws on at least two interacting components: semantic representations [degraded in semantic dementia (SD)] and control processes [deficient in patients with multimodal semantic impairment following stroke aphasia (SA)]. To explore the first component, we employed distortion-corrected functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) in healthy volunteers: these studies convergently indicated that the anterior temporal lobes (ATLs; atrophied in SD) combine information from different modalities within an amodal semantic "hub". Regions of cortex that code specific semantic features ("spokes") also make a critical contribution to knowledge within particular categories. This network of brain regions interacts with semantic control processes reliant on left inferior frontal gyrus (LIFG), posterior middle temporal gyrus (pMTG) and inferior parietal cortices. SA patients with damage to these regions have difficulty focussing on aspects of knowledge that are relevant to the current goal or context, in both verbal and non-verbal tasks. SA patients with LIFG and temporoparietal lesions show similar deficits of semantic control, suggesting that a large-scale distributed cortical network underpins semantic control. Convergent evidence is again provided by fMRI and TMS. We separately manipulated the representational and control demands of a semantic task in fMRI, and found a dissociation within the temporal lobe: ATL was sensitive to the number of meanings retrieved, while pMTG and LIFG showed effects of semantic selection. Moreover, TMS to LIFG and pMTG produced equal disruption of tasks tapping semantic control. The next challenges are to delineate the

  7. Evidence for a neural source of the precedence effect in sound localization.

    Science.gov (United States)

    Brown, Andrew D; Jones, Heath G; Kan, Alan; Thakkar, Tanvi; Stecker, G Christopher; Goupell, Matthew J; Litovsky, Ruth Y

    2015-11-01

    Normal-hearing human listeners and a variety of studied animal species localize sound sources accurately in reverberant environments by responding to the directional cues carried by the first-arriving sound rather than spurious cues carried by later-arriving reflections, which are not perceived discretely. This phenomenon is known as the precedence effect (PE) in sound localization. Despite decades of study, the biological basis of the PE remains unclear. Though the PE was once widely attributed to central processes such as synaptic inhibition in the auditory midbrain, a more recent hypothesis holds that the PE may arise essentially as a by-product of normal cochlear function. Here we evaluated the PE in a unique human patient population with demonstrated sensitivity to binaural information but without functional cochleae. Users of bilateral cochlear implants (CIs) were tested in a psychophysical task that assessed the number and location(s) of auditory images perceived for simulated source-echo (lead-lag) stimuli. A parallel experiment was conducted in a group of normal-hearing (NH) listeners. Key findings were as follows: 1) Subjects in both groups exhibited lead-lag fusion. 2) Fusion was marginally weaker in CI users than in NH listeners but could be augmented by systematically attenuating the amplitude of the lag stimulus to coarsely simulate adaptation observed in acoustically stimulated auditory nerve fibers. 3) Dominance of the lead in localization varied substantially among both NH and CI subjects but was evident in both groups. Taken together, data suggest that aspects of the PE can be elicited in CI users, who lack functional cochleae, thus suggesting that neural mechanisms are sufficient to produce the PE.

  8. Neural correlates of uncertain decision making: ERP evidence from the Iowa Gambling Task

    Directory of Open Access Journals (Sweden)

    Ji-fang eCui

    2013-11-01

    Full Text Available In our daily life, it is very common to make decisions in uncertain situations. The Iowa Gambling Task (IGT has been widely used in laboratory studies because of its good simulation of uncertainty in real life activities. The present study aimed to examine the neural correlates of uncertain decision making with the IGT. Twenty-six university students completed this study. An adapted IGT was administered to them, and the EEG data were recorded. The adapted IGT we used allowed us to analyze the choice evaluation, response selection, and feedback evaluation stages of uncertain decision making within the same paradigm. In the choice evaluation stage, the advantageous decks evoked larger P3 amplitude in the left hemisphere, while the disadvantageous decks evoked larger P3 in the right hemisphere. In the response selection stage, the response of pass (the card was not turned over; the participants neither won nor lost money evoked larger negativity preceding the response compared to that of play (the card was turned over; the participant either won or lost money. In the feedback evaluation stage, feedback-related negativity was only sensitive to the valence (win/loss but not the magnitude (large/small of the outcome, and P3 was sensitive to both the valence and the magnitude of the outcome. These results were consistent with the notion that a positive somatic state was represented in the left hemisphere and a negative somatic state was represented in the right hemisphere. There were also anticipatory ERP effects that guided the participants’ responses and provided evidence for the somatic marker hypothesis with more precise timing.

  9. Deciding not to decide: computational and neural evidence for hidden behavior in sequential choice.

    Science.gov (United States)

    Gluth, Sebastian; Rieskamp, Jörg; Büchel, Christian

    2013-10-01

    Understanding the cognitive and neural processes that underlie human decision making requires the successful prediction of how, but also of when, people choose. Sequential sampling models (SSMs) have greatly advanced the decision sciences by assuming decisions to emerge from a bounded evidence accumulation process so that response times (RTs) become predictable. Here, we demonstrate a difficulty of SSMs that occurs when people are not forced to respond at once but are allowed to sample information sequentially: The decision maker might decide to delay the choice and terminate the accumulation process temporarily, a scenario not accounted for by the standard SSM approach. We developed several SSMs for predicting RTs from two independent samples of an electroencephalography (EEG) and a functional magnetic resonance imaging (fMRI) study. In these studies, participants bought or rejected fictitious stocks based on sequentially presented cues and were free to respond at any time. Standard SSM implementations did not describe RT distributions adequately. However, by adding a mechanism for postponing decisions to the model we obtained an accurate fit to the data. Time-frequency analysis of EEG data revealed alternating states of de- and increasing oscillatory power in beta-band frequencies (14-30 Hz), indicating that responses were repeatedly prepared and inhibited and thus lending further support for the existence of a decision not to decide. Finally, the extended model accounted for the results of an adapted version of our paradigm in which participants had to press a button for sampling more information. Our results show how computational modeling of decisions and RTs support a deeper understanding of the hidden dynamics in cognition.

  10. Deciding not to decide: computational and neural evidence for hidden behavior in sequential choice.

    Directory of Open Access Journals (Sweden)

    Sebastian Gluth

    2013-10-01

    Full Text Available Understanding the cognitive and neural processes that underlie human decision making requires the successful prediction of how, but also of when, people choose. Sequential sampling models (SSMs have greatly advanced the decision sciences by assuming decisions to emerge from a bounded evidence accumulation process so that response times (RTs become predictable. Here, we demonstrate a difficulty of SSMs that occurs when people are not forced to respond at once but are allowed to sample information sequentially: The decision maker might decide to delay the choice and terminate the accumulation process temporarily, a scenario not accounted for by the standard SSM approach. We developed several SSMs for predicting RTs from two independent samples of an electroencephalography (EEG and a functional magnetic resonance imaging (fMRI study. In these studies, participants bought or rejected fictitious stocks based on sequentially presented cues and were free to respond at any time. Standard SSM implementations did not describe RT distributions adequately. However, by adding a mechanism for postponing decisions to the model we obtained an accurate fit to the data. Time-frequency analysis of EEG data revealed alternating states of de- and increasing oscillatory power in beta-band frequencies (14-30 Hz, indicating that responses were repeatedly prepared and inhibited and thus lending further support for the existence of a decision not to decide. Finally, the extended model accounted for the results of an adapted version of our paradigm in which participants had to press a button for sampling more information. Our results show how computational modeling of decisions and RTs support a deeper understanding of the hidden dynamics in cognition.

  11. Work at night and breast cancer - report on evidence-based options for preventive actions

    DEFF Research Database (Denmark)

    Bonde, Jens Peter; Hansen, Johnni; Kolstad, Henrik A.

    2012-01-01

    actions, 16 researchers in basic, epidemiological and applied sciences convened at a workshop in Copenhagen 26-27 October 2011. This paper summarizes the evidence from epidemiological and experimental studies and presents possible recommendations for prevention of the effects of night work on breast...... cancer. Among those studies that quantified duration of shift work, there were statistically significant elevations in risk only after about 20 years working night shift. It is unclear from these studies whether or not there is a modest but real elevated risk for shorter durations. Hence, restriction...... by suppression of melatonin secretion. Work during the night is widespread worldwide. To provide additional evidence-based recommendations on prevention of diseases related to night shift work, large studies on the impact of various shift schedules and type of light on circadian rhythms need to be conducted...

  12. Connectivity patterns during music listening: Evidence for action-based processing in musicians.

    Science.gov (United States)

    Alluri, Vinoo; Toiviainen, Petri; Burunat, Iballa; Kliuchko, Marina; Vuust, Peter; Brattico, Elvira

    2017-03-28

    Musical expertise is visible both in the morphology and functionality of the brain. Recent research indicates that functional integration between multi-sensory, somato-motor, default-mode (DMN), and salience (SN) networks of the brain differentiates musicians from non-musicians during resting state. Here, we aimed at determining whether brain networks differentially exchange information in musicians as opposed to non-musicians during naturalistic music listening. Whole-brain graph-theory analyses were performed on participants' fMRI responses. Group-level differences revealed that musicians' primary hubs comprised cerebral and cerebellar sensorimotor regions whereas non-musicians' dominant hubs encompassed DMN-related regions. Community structure analyses of the key hubs revealed greater integration of motor and somatosensory homunculi representing the upper limbs and torso in musicians. Furthermore, musicians who started training at an earlier age exhibited greater centrality in the auditory cortex, and areas related to top-down processes, attention, emotion, somatosensory processing, and non-verbal processing of speech. We here reveal how brain networks organize themselves in a naturalistic music listening situation wherein musicians automatically engage neural networks that are action-based while non-musicians use those that are perception-based to process an incoming auditory stream. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

  13. Granger causality mapping during joint actions reveals evidence for forward models that could overcome sensory-motor delays.

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    Idil Kokal

    Full Text Available Studies investigating joint actions have suggested a central role for the putative mirror neuron system (pMNS because of the close link between perception and action provided by these brain regions [1], [2], [3]. In contrast, our previous functional magnetic resonance imaging (fMRI experiment demonstrated that the BOLD response of the pMNS does not suggest that it directly integrates observed and executed actions during joint actions [4]. To test whether the pMNS might contribute indirectly to the integration process by sending information to brain areas responsible for this integration (integration network, here we used Granger causality mapping (GCM [5]. We explored the directional information flow between the anterior sites of the pMNS and previously identified integrative brain regions. We found that the left BA44 sent more information than it received to both the integration network (left thalamus, right middle occipital gyrus and cerebellum and more posterior nodes of the pMNS (BA2. Thus, during joint actions, two anatomically separate networks therefore seem effectively connected and the information flow is predominantly from anterior to posterior areas of the brain. These findings suggest that the pMNS is involved indirectly in joint actions by transforming observed and executed actions into a common code and is part of a generative model that could predict the future somatosensory and visual consequences of observed and executed actions in order to overcome otherwise inevitable neural delays.

  14. Interprofessional collaborative practice within cancer teams: Translating evidence into action. A mixed methods study protocol

    Directory of Open Access Journals (Sweden)

    Roberge Danièle

    2010-07-01

    Full Text Available Abstract Background A regional integrated cancer network has implemented a program (educational workshops, reflective and mentoring activities designed to support the uptake of evidence-informed interprofessional collaborative practices (referred to in this text as EIPCP within cancer teams. This research project, which relates to the Registered Nurses' Association of Ontario (RNAO Best Practice Guidelines and other sources of research evidence, represents a unique opportunity to learn more about the factors and processes involved in the translation of evidence-based recommendations into professional practices. The planned study seeks to address context-specific challenges and the concerns of nurses and other stakeholders regarding the uptake of evidence-based recommendations to effectively promote and support interprofessional collaborative practices. Aim This study aims to examine the uptake of evidence-based recommendations from best practice guidelines intended to enhance interprofessional collaborative practices within cancer teams. Design The planned study constitutes a practical trial, defined as a trial designed to provide comprehensive information that is grounded in real-world healthcare dynamics. An exploratory mixed methods study design will be used. It will involve collecting quantitative data to assess professionals' knowledge and attitudes, as well as practice environment factors associated with effective uptake of evidence-based recommendations. Semi-structured interviews will be conducted concurrently with care providers to gather qualitative data for describing the processes involved in the translation of evidence into action from both the users' (n = 12 and providers' (n = 24 perspectives. The Graham et al. Ottawa Model of Research Use will serve to construct operational definitions of concepts, and to establish the initial coding labels to be used in the thematic analysis of the qualitative data. Quantitative and qualitative

  15. "Cuts in Action": A High-Density EEG Study Investigating the Neural Correlates of Different Editing Techniques in Film.

    Science.gov (United States)

    Heimann, Katrin S; Uithol, Sebo; Calbi, Marta; Umiltà, Maria A; Guerra, Michele; Gallese, Vittorio

    2016-11-24

    In spite of their striking differences with real-life perception, films are perceived and understood without effort. Cognitive film theory attributes this to the system of continuity editing, a system of editing guidelines outlining the effect of different cuts and edits on spectators. A major principle in this framework is the 180° rule, a rule recommendation that, to avoid spectators' attention to the editing, two edited shots of the same event or action should not be filmed from angles differing in a way that expectations of spatial continuity are strongly violated. In the present study, we used high-density EEG to explore the neural underpinnings of this rule. In particular, our analysis shows that cuts and edits in general elicit early ERP component indicating the registration of syntactic violations as known from language, music, and action processing. However, continuity edits and cuts-across the line differ from each other regarding later components likely to be indicating the differences in spatial remapping as well as in the degree of conscious awareness of one's own perception. Interestingly, a time-frequency analysis of the occipital alpha rhythm did not support the hypothesis that such differences in processing routes are mainly linked to visual attention. On the contrary, our study found specific modulations of the central mu rhythm ERD as an indicator of sensorimotor activity, suggesting that sensorimotor networks might play an important role. We think that these findings shed new light on current discussions about the role of attention and embodied perception in film perception and should be considered when explaining spectators' different experience of different kinds of cuts.

  16. Facial Action and Emotional Language: ERP Evidence that Blocking Facial Feedback Selectively Impairs Sentence Comprehension.

    Science.gov (United States)

    Davis, Joshua D; Winkielman, Piotr; Coulson, Seana

    2015-11-01

    There is a lively and theoretically important debate about whether, how, and when embodiment contributes to language comprehension. This study addressed these questions by testing how interference with facial action impacts the brain's real-time response to emotional language. Participants read sentences about positive and negative events (e.g., "She reached inside the pocket of her coat from last winter and found some (cash/bugs) inside it.") while ERPs were recorded. Facial action was manipulated within participants by asking participants to hold chopsticks in their mouths using a position that allowed or blocked smiling, as confirmed by EMG. Blocking smiling did not influence ERPs to the valenced words (e.g., cash, bugs) but did influence ERPs to final words of sentences describing positive events. Results show that affectively positive sentences can evoke smiles and that such facial action can facilitate the semantic processing indexed by the N400 component. Overall, this study offers causal evidence that embodiment impacts some aspects of high-level comprehension, presumably involving the construction of the situation model.

  17. Motor imagery during action observation: A brief review of evidence, theory and future research opportunities

    Directory of Open Access Journals (Sweden)

    Daniel Lloyd Eaves

    2016-11-01

    Full Text Available Motor imagery (MI and action observation (AO have traditionally been viewed as two separate techniques, which can both be used alongside physical practice to enhance motor learning and rehabilitation. Their independent use has been shown to be effective, and there is clear evidence that the two processes can elicit similar activity in the motor system. Building on these well-established findings, research has now turned to investigate the effects of their combined use. In this article, we first review the available neurophysiological and behavioral evidence for the effects of combined action observation and motor imagery (‘AO+MI’ on motor processes. We next describe a conceptual framework for their combined use, and then discuss several areas for future research into AO+MI processes. In this review, we advocate a more integrated approach to AO+MI techniques than has previously been adopted by movement scientists and practitioners alike. We hope this early review of an emergent body of research, along with a related set of research questions, can inspire new work in this area. We are optimistic that future research will further confirm if, how, and when this combined approach to AO+MI can be more effective in motor learning and rehabilitation settings, relative to the more traditional application of AO or MI independently.

  18. The music of your emotions: neural substrates involved in detection of emotional correspondence between auditory and visual music actions.

    Science.gov (United States)

    Petrini, Karin; Crabbe, Frances; Sheridan, Carol; Pollick, Frank E

    2011-04-29

    In humans, emotions from music serve important communicative roles. Despite a growing interest in the neural basis of music perception, action and emotion, the majority of previous studies in this area have focused on the auditory aspects of music performances. Here we investigate how the brain processes the emotions elicited by audiovisual music performances. We used event-related functional magnetic resonance imaging, and in Experiment 1 we defined the areas responding to audiovisual (musician's movements with music), visual (musician's movements only), and auditory emotional (music only) displays. Subsequently a region of interest analysis was performed to examine if any of the areas detected in Experiment 1 showed greater activation for emotionally mismatching performances (combining the musician's movements with mismatching emotional sound) than for emotionally matching music performances (combining the musician's movements with matching emotional sound) as presented in Experiment 2 to the same participants. The insula and the left thalamus were found to respond consistently to visual, auditory and audiovisual emotional information and to have increased activation for emotionally mismatching displays in comparison with emotionally matching displays. In contrast, the right thalamus was found to respond to audiovisual emotional displays and to have similar activation for emotionally matching and mismatching displays. These results suggest that the insula and left thalamus have an active role in detecting emotional correspondence between auditory and visual information during music performances, whereas the right thalamus has a different role.

  19. The music of your emotions: neural substrates involved in detection of emotional correspondence between auditory and visual music actions.

    Directory of Open Access Journals (Sweden)

    Karin Petrini

    Full Text Available In humans, emotions from music serve important communicative roles. Despite a growing interest in the neural basis of music perception, action and emotion, the majority of previous studies in this area have focused on the auditory aspects of music performances. Here we investigate how the brain processes the emotions elicited by audiovisual music performances. We used event-related functional magnetic resonance imaging, and in Experiment 1 we defined the areas responding to audiovisual (musician's movements with music, visual (musician's movements only, and auditory emotional (music only displays. Subsequently a region of interest analysis was performed to examine if any of the areas detected in Experiment 1 showed greater activation for emotionally mismatching performances (combining the musician's movements with mismatching emotional sound than for emotionally matching music performances (combining the musician's movements with matching emotional sound as presented in Experiment 2 to the same participants. The insula and the left thalamus were found to respond consistently to visual, auditory and audiovisual emotional information and to have increased activation for emotionally mismatching displays in comparison with emotionally matching displays. In contrast, the right thalamus was found to respond to audiovisual emotional displays and to have similar activation for emotionally matching and mismatching displays. These results suggest that the insula and left thalamus have an active role in detecting emotional correspondence between auditory and visual information during music performances, whereas the right thalamus has a different role.

  20. Signed language and human action processing: evidence for functional constraints on the human mirror-neuron system.

    Science.gov (United States)

    Corina, David P; Knapp, Heather Patterson

    2008-12-01

    In the quest to further understand the neural underpinning of human communication, researchers have turned to studies of naturally occurring signed languages used in Deaf communities. The comparison of the commonalities and differences between spoken and signed languages provides an opportunity to determine core neural systems responsible for linguistic communication independent of the modality in which a language is expressed. The present article examines such studies, and in addition asks what we can learn about human languages by contrasting formal visual-gestural linguistic systems (signed languages) with more general human action perception. To understand visual language perception, it is important to distinguish the demands of general human motion processing from the highly task-dependent demands associated with extracting linguistic meaning from arbitrary, conventionalized gestures. This endeavor is particularly important because theorists have suggested close homologies between perception and production of actions and functions of human language and social communication. We review recent behavioral, functional imaging, and neuropsychological studies that explore dissociations between the processing of human actions and signed languages. These data suggest incomplete overlap between the mirror-neuron systems proposed to mediate human action and language.

  1. Modelling and evaluating customer loyalty using neural networks: Evidence from startup insurance companies

    Directory of Open Access Journals (Sweden)

    Azarnoush Ansari

    2016-06-01

    Full Text Available The purpose of this study is to investigate the customer–service provider relationship in the insurance industry using artificial neural networks and linear regression. Using a sample of 389 customers from 10 different startup insurance companies, it was found that artificial neural networks are an efficient way to evaluate the factors affecting customer loyalty. The results indicated that customer satisfaction and perceived value are significant predictors of customer loyalty. Additionally, it was found that trust, perceived quality, and empathy have a significant impact on both customer satisfaction and perceived value. The results also showed that customer commitment to service provider is positively associated with customer satisfaction and loyalty. After comparing the performance of linear regression models with artificial neural networks, it was found that the use of neural networks is a better approach for analyzing the customer loyalty, satisfaction, and perceived value. The use of new techniques such as artificial neural networks for analyzing the customer behavior can be particularly beneficial for startup companies who aspire to gain competitive advantage over their strong and well-established rivals.

  2. The Neural Correlates Underlying Belief Reasoning for Self and for Others: Evidence from ERPs

    Science.gov (United States)

    Jiang, Qin; Wang, Qi; Li, Peng; Li, Hong

    2016-01-01

    Belief reasoning is typical mental state reasoning in theory of mind (ToM). Although previous studies have explored the neural bases of belief reasoning, the neural correlates of belief reasoning for self and for others are rarely addressed. The decoupling mechanism of distinguishing the mental state of others from one’s own is essential for ToM processing. To address the electrophysiological bases underlying the decoupling mechanism, the present event-related potential study compared the time course of neural activities associated with belief reasoning for self and for others when the belief belonging to self was consistent or inconsistent with others. Results showed that during a 450–600 ms period, belief reasoning for self elicited a larger late positive component (LPC) than for others when beliefs were inconsistent with each other. The LPC divergence is assumed to reflect the categorization of agencies in ToM processes. PMID:27757093

  3. An action-incongruent secondary task modulates prediction accuracy in experienced performers: evidence for motor simulation.

    Science.gov (United States)

    Mulligan, Desmond; Lohse, Keith R; Hodges, Nicola J

    2016-07-01

    We provide behavioral evidence that the human motor system is involved in the perceptual decision processes of skilled performers, directly linking prediction accuracy to the (in)ability of the motor system to activate in a response-specific way. Experienced and non-experienced dart players were asked to predict, from temporally occluded video sequences, the landing position of a dart thrown previously by themselves (self) or another (other). This prediction task was performed while additionally performing (a) an action-incongruent secondary motor task (right arm force production), (b) a congruent secondary motor task (mimicking) or (c) an attention-matched task (tone-monitoring). Non-experienced dart players were not affected by any of the secondary task manipulations, relative to control conditions, yet prediction accuracy decreased for the experienced players when additionally performing the force-production, motor task. This interference effect was present for 'self' as well as 'other' decisions, reducing the accuracy of experienced participants to a novice level. The mimicking (congruent) secondary task condition did not interfere with (or facilitate) prediction accuracy for either group. We conclude that visual-motor experience moderates the process of decision making, such that a seemingly visual-cognitive prediction task relies on activation of the motor system for experienced performers. This fits with a motor simulation account of action prediction in sports and other tasks, and alerts to the specificity of these simulative processes.

  4. Poverty and child health in the UK: using evidence for action.

    Science.gov (United States)

    Wickham, Sophie; Anwar, Elspeth; Barr, Ben; Law, Catherine; Taylor-Robinson, David

    2016-08-01

    There are currently high levels of child poverty in the UK, and for the first time in almost two decades child poverty has started to rise in absolute terms. Child poverty is associated with a wide range of health-damaging impacts, negative educational outcomes and adverse long-term social and psychological outcomes. The poor health associated with child poverty limits children's potential and development, leading to poor health and life chances in adulthood. This article outlines some key definitions with regard to child poverty, reviews the links between child poverty and a range of health, developmental, behavioural and social outcomes for children, describes gaps in the evidence base and provides an overview of current policies relevant to child poverty in the UK. Finally, the article outlines how child health professionals can take action by (1) supporting policies to reduce child poverty, (2) providing services that reduce the health consequences of child poverty and (3) measuring and understanding the problem and assessing the impact of action.

  5. Poverty and child health in the UK: using evidence for action

    Science.gov (United States)

    Wickham, Sophie; Anwar, Elspeth; Barr, Ben; Law, Catherine; Taylor-Robinson, David

    2016-01-01

    There are currently high levels of child poverty in the UK, and for the first time in almost two decades child poverty has started to rise in absolute terms. Child poverty is associated with a wide range of health-damaging impacts, negative educational outcomes and adverse long-term social and psychological outcomes. The poor health associated with child poverty limits children's potential and development, leading to poor health and life chances in adulthood. This article outlines some key definitions with regard to child poverty, reviews the links between child poverty and a range of health, developmental, behavioural and social outcomes for children, describes gaps in the evidence base and provides an overview of current policies relevant to child poverty in the UK. Finally, the article outlines how child health professionals can take action by (1) supporting policies to reduce child poverty, (2) providing services that reduce the health consequences of child poverty and (3) measuring and understanding the problem and assessing the impact of action. PMID:26857824

  6. Neural Basis of Intrinsic Motivation: Evidence from Event-Related Potentials

    Directory of Open Access Journals (Sweden)

    Jia Jin

    2015-01-01

    Full Text Available Human intrinsic motivation is of great importance in human behavior. However, although researchers have focused on this topic for decades, its neural basis was still unclear. The current study employed event-related potentials to investigate the neural disparity between an interesting stop-watch (SW task and a boring watch-stop task (WS to understand the neural mechanisms of intrinsic motivation. Our data showed that, in the cue priming stage, the cue of the SW task elicited smaller N2 amplitude than that of the WS task. Furthermore, in the outcome feedback stage, the outcome of the SW task induced smaller FRN amplitude and larger P300 amplitude than that of the WS task. These results suggested that human intrinsic motivation did exist and that it can be detected at the neural level. Furthermore, intrinsic motivation could be quantitatively indexed by the amplitude of ERP components, such as N2, FRN, and P300, in the cue priming stage or feedback stage. Quantitative measurements would also be convenient for intrinsic motivation to be added as a candidate social factor in the construction of a machine learning model.

  7. Neural Basis of Intrinsic Motivation: Evidence from Event-Related Potentials.

    Science.gov (United States)

    Jin, Jia; Yu, Liping; Ma, Qingguo

    2015-01-01

    Human intrinsic motivation is of great importance in human behavior. However, although researchers have focused on this topic for decades, its neural basis was still unclear. The current study employed event-related potentials to investigate the neural disparity between an interesting stop-watch (SW) task and a boring watch-stop task (WS) to understand the neural mechanisms of intrinsic motivation. Our data showed that, in the cue priming stage, the cue of the SW task elicited smaller N2 amplitude than that of the WS task. Furthermore, in the outcome feedback stage, the outcome of the SW task induced smaller FRN amplitude and larger P300 amplitude than that of the WS task. These results suggested that human intrinsic motivation did exist and that it can be detected at the neural level. Furthermore, intrinsic motivation could be quantitatively indexed by the amplitude of ERP components, such as N2, FRN, and P300, in the cue priming stage or feedback stage. Quantitative measurements would also be convenient for intrinsic motivation to be added as a candidate social factor in the construction of a machine learning model.

  8. Neural systems for social cognition in Klinefelter syndrome (47.XXY) : evidence from fMRI

    NARCIS (Netherlands)

    van Rijn, S.; Swaab, H; Baas, D; de Haan, E; Kahn, R.S.; Aleman, A.

    2012-01-01

    Klinefelter syndrome (KS) is a chromosomal condition (47, XXY) that may help us to unravel gene-brain behavior pathways to psychopathology. The phenotype includes social cognitive impairments and increased risk for autism traits. We used functional MRI to study neural mechanisms underlying social in

  9. Neural Correlates of Visual Perceptual Expertise: Evidence from Cognitive Neuroscience Using Functional Neuroimaging

    Science.gov (United States)

    Gegenfurtner, Andreas; Kok, Ellen M.; van Geel, Koos; de Bruin, Anique B. H.; Sorger, Bettina

    2017-01-01

    Functional neuroimaging is a useful approach to study the neural correlates of visual perceptual expertise. The purpose of this paper is to review the functional-neuroimaging methods that have been implemented in previous research in this context. First, we will discuss research questions typically addressed in visual expertise research. Second,…

  10. Neural Signatures of Number Processing in Human Infants: Evidence for Two Core Systems Underlying Numerical Cognition

    Science.gov (United States)

    Hyde, Daniel C.; Spelke, Elizabeth S.

    2011-01-01

    Behavioral research suggests that two cognitive systems are at the foundations of numerical thinking: one for representing 1-3 objects in parallel and one for representing and comparing large, approximate numerical magnitudes. We tested for dissociable neural signatures of these systems in preverbal infants by recording event-related potentials…

  11. cables1 is required for embryonic neural development: molecular, cellular, and behavioral evidence from the zebrafish.

    Science.gov (United States)

    Groeneweg, Jolijn W; White, Yvonne A R; Kokel, David; Peterson, Randall T; Zukerberg, Lawrence R; Berin, Inna; Rueda, Bo R; Wood, Antony W

    2011-01-01

    In vitro studies have suggested that the Cables1 gene regulates epithelial cell proliferation, whereas other studies suggest a role in promoting neural differentiation. In efforts to clarify the functions of Cables1 in vivo, we conducted gain- and loss-of-function studies targeting its ortholog (cables1) in the zebrafish embryo. Similar to rodents, zebrafish cables1 mRNA expression is detected most robustly in embryonic neural tissues. Antisense knockdown of cables1 leads to increased numbers of apoptotic cells, particularly in brain tissue, in addition to a distinct behavioral phenotype, characterized by hyperactivity in response to stimulation. Apoptosis and the behavioral abnormality could be rescued by co-expression of a morpholino-resistant cables1 construct. Suppression of p53 expression in cables1 morphants partially rescued both apoptosis and the behavioral phenotype, suggesting that the phenotype of cables1 morphants is due in part to p53-dependent apoptosis. Alterations in the expression patterns of several neural transcription factors were observed in cables1 morphants during early neurulation, suggesting that cables1 is required for early neural differentiation. Ectopic overexpression of cables1 strongly disrupted embryonic morphogenesis, while overexpression of a cables1 mutant lacking the C-terminal cyclin box had little effect, suggesting functional importance of the cyclin box. Lastly, marked reductions in p35, but not Cdk5, were observed in cables1 morphants. Collectively, these data suggest that cables1 is important for neural differentiation during embryogenesis, in a mechanism that likely involves interactions with the Cdk5/p35 kinase pathway.

  12. Erythropoietin modulates neural and cognitive processing of emotional information in biomarker models of antidepressant drug action in depressed patients

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla W; Favaron, Elisa; Hafizi, Sepehr

    2010-01-01

    Erythropoietin (Epo) has neuroprotective and neurotrophic effects, and may be a novel therapeutic agent in the treatment of psychiatric disorders. We have demonstrated antidepressant-like effects of Epo on the neural and cognitive processing of facial expressions in healthy volunteers. The current...... study investigates the effects of Epo on the neural and cognitive response to emotional facial expressions in depressed patients....

  13. On the Nature of the Intrinsic Connectivity of the Cat Motor Cortex: Evidence for a Recurrent Neural Network Topology

    DEFF Research Database (Denmark)

    Capaday, Charles; Ethier, C; Brizzi, L

    2009-01-01

    Capaday C, Ethier C, Brizzi L, Sik A, van Vreeswijk C, Gingras D. On the nature of the intrinsic connectivity of the cat motor cortex: evidence for a recurrent neural network topology. J Neurophysiol 102: 2131-2141, 2009. First published July 22, 2009; doi: 10.1152/jn.91319.2008. The details...... and functional significance of the intrinsic horizontal connections between neurons in the motor cortex (MCx) remain to be clarified. To further elucidate the nature of this intracortical connectivity pattern, experiments were done on the MCx of three cats. The anterograde tracer biocytin was ejected...

  14. Evidence for Neural Computations of Temporal Coherence in an Auditory Scene and Their Enhancement during Active Listening.

    Science.gov (United States)

    O'Sullivan, James A; Shamma, Shihab A; Lalor, Edmund C

    2015-05-06

    The human brain has evolved to operate effectively in highly complex acoustic environments, segregating multiple sound sources into perceptually distinct auditory objects. A recent theory seeks to explain this ability by arguing that stream segregation occurs primarily due to the temporal coherence of the neural populations that encode the various features of an individual acoustic source. This theory has received support from both psychoacoustic and functional magnetic resonance imaging (fMRI) studies that use stimuli which model complex acoustic environments. Termed stochastic figure-ground (SFG) stimuli, they are composed of a "figure" and background that overlap in spectrotemporal space, such that the only way to segregate the figure is by computing the coherence of its frequency components over time. Here, we extend these psychoacoustic and fMRI findings by using the greater temporal resolution of electroencephalography to investigate the neural computation of temporal coherence. We present subjects with modified SFG stimuli wherein the temporal coherence of the figure is modulated stochastically over time, which allows us to use linear regression methods to extract a signature of the neural processing of this temporal coherence. We do this under both active and passive listening conditions. Our findings show an early effect of coherence during passive listening, lasting from ∼115 to 185 ms post-stimulus. When subjects are actively listening to the stimuli, these responses are larger and last longer, up to ∼265 ms. These findings provide evidence for early and preattentive neural computations of temporal coherence that are enhanced by active analysis of an auditory scene.

  15. Neural Correlates of Developmental Speech and Language Disorders: Evidence from Neuroimaging.

    Science.gov (United States)

    Liégeois, Frédérique; Mayes, Angela; Morgan, Angela

    2014-01-01

    Disorders of speech and language arise out of a complex interaction of genetic, environmental, and neural factors. Little is understood about the neural bases of these disorders. Here we systematically reviewed neuroimaging findings in Speech disorders (SD) and Language disorders (LD) over the last five years (2008-2013; 10 articles). In participants with SD, structural and functional anomalies in the left supramarginal gyrus suggest a possible deficit in sensory feedback or integration. In LD, cortical and subcortical anomalies were reported in a widespread language network, with little consistency across studies except in the superior temporal gyri. In summary, both functional and structural anomalies are associated with LD and SD, including greater activity and volumes relative to controls. The variability in neuroimaging approach and heterogeneity within and across participant samples restricts our full understanding of the neurobiology of these conditions- reducing the potential for devising novel interventions targeted at the underlying pathology.

  16. The moon illusion and size-distance scaling--evidence for shared neural patterns.

    Science.gov (United States)

    Weidner, Ralph; Plewan, Thorsten; Chen, Qi; Buchner, Axel; Weiss, Peter H; Fink, Gereon R

    2014-08-01

    A moon near to the horizon is perceived larger than a moon at the zenith, although--obviously--the moon does not change its size. In this study, the neural mechanisms underlying the "moon illusion" were investigated using a virtual 3-D environment and fMRI. Illusory perception of an increased moon size was associated with increased neural activity in ventral visual pathway areas including the lingual and fusiform gyri. The functional role of these areas was further explored in a second experiment. Left V3v was found to be involved in integrating retinal size and distance information, thus indicating that the brain regions that dynamically integrate retinal size and distance play a key role in generating the moon illusion.

  17. Neural evidence that three dimensions organize mental state representation: Rationality, social impact, and valence.

    Science.gov (United States)

    Tamir, Diana I; Thornton, Mark A; Contreras, Juan Manuel; Mitchell, Jason P

    2016-01-05

    How do people understand the minds of others? Existing psychological theories have suggested a number of dimensions that perceivers could use to make sense of others' internal mental states. However, it remains unclear which of these dimensions, if any, the brain spontaneously uses when we think about others. The present study used multivoxel pattern analysis (MVPA) of neuroimaging data to identify the primary organizing principles of social cognition. We derived four unique dimensions of mental state representation from existing psychological theories and used functional magnetic resonance imaging to test whether these dimensions organize the neural encoding of others' mental states. MVPA revealed that three such dimensions could predict neural patterns within the medial prefrontal and parietal cortices, temporoparietal junction, and anterior temporal lobes during social thought: rationality, social impact, and valence. These results suggest that these dimensions serve as organizing principles for our understanding of other people.

  18. Neural networks and forecasting stock price movements-accounting approach: Empirical evidence from Iran

    Directory of Open Access Journals (Sweden)

    Hossein Naderi

    2012-08-01

    Full Text Available Stock market prediction is one of the most important interesting areas of research in business. Stock markets prediction is normally assumed as tedious task since there are many factors influencing the market. The primary objective of this paper is to forecast trend closing price movement of Tehran Stock Exchange (TSE using financial accounting ratios from year 2003 to year 2008. The proposed study of this paper uses two approaches namely Artificial Neural Networks and multi-layer perceptron. Independent variables are accounting ratios and dependent variable of stock price , so the latter was gathered for the industry of Motor Vehicles and Auto Parts. The results of this study show that neural networks models are useful tools in forecasting stock price movements in emerging markets but multi-layer perception provides better results in term of lowering error terms.

  19. Bilingualism increases neural response consistency and attentional control: evidence for sensory and cognitive coupling.

    Science.gov (United States)

    Krizman, Jennifer; Skoe, Erika; Marian, Viorica; Kraus, Nina

    2014-01-01

    Auditory processing is presumed to be influenced by cognitive processes - including attentional control - in a top-down manner. In bilinguals, activation of both languages during daily communication hones inhibitory skills, which subsequently bolster attentional control. We hypothesize that the heightened attentional demands of bilingual communication strengthens connections between cognitive (i.e., attentional control) and auditory processing, leading to greater across-trial consistency in the auditory evoked response (i.e., neural consistency) in bilinguals. To assess this, we collected passively-elicited auditory evoked responses to the syllable [da] in adolescent Spanish-English bilinguals and English monolinguals and separately obtained measures of attentional control and language ability. Bilinguals demonstrated enhanced attentional control and more consistent brainstem and cortical responses. In bilinguals, but not monolinguals, brainstem consistency tracked with language proficiency and attentional control. We interpret these enhancements in neural consistency as the outcome of strengthened attentional control that emerged from experience communicating in two languages.

  20. Neural evidence for a distinction between short-term memory and the focus of attention

    OpenAIRE

    Lewis-Peacock, Jarrod A.; Drysdale, Andrew T.; Oberauer, Klaus; Postle, Bradley R.

    2012-01-01

    It is widely assumed that the short-term retention of information is accomplished via maintenance of an active neural trace. However, we demonstrate that memory can be preserved across a brief delay despite the apparent loss of sustained representations. Delay-period activity may in fact reflect the focus of attention, rather than short-term memory. We unconfounded attention and memory by causing external and internal shifts of attention away from items that were being actively retained. Mult...

  1. Altered Neural Substrates of Cognitive Control in Childhood ADHD: Evidence From Functional Magnetic Resonance Imaging

    Science.gov (United States)

    Vaidya, Chandan J.; Bunge, Silvia A.; Dudukovic, Nicole M.; Zalecki, Christine A.; Elliott, Glen R.; Gabrieli, John D.E.

    2015-01-01

    Objective The study compared the neural bases of two cognitive control operations, interference suppression and response inhibition, between children with and children without attention deficit hyperactivity disorder (ADHD). Method Ten children (7–11 years of age) with combined-type ADHD and 10 comparison subjects matched for age and gender underwent rapid event-related functional magnetic resonance imaging (fMRI) during performance of a modified flanker task. Functional maps were generated through group averaging and performance-based correlational analyses. Results Interference suppression in ADHD subjects was characterized by reduced engagement of a frontal-striatal-temporal-parietal network that subserved healthy performance. In contrast, response inhibition performance relied upon different regions in the two groups, frontal-striatal in comparison subjects but right superior temporal in ADHD children. Conclusions Alteration in the neural basis of two cognitive control operations in childhood ADHD was characterized by distinct, rather than unitary, patterns of functional abnormality. Greater between-group overlap in the neural network activated for interference suppression than in response inhibition suggests that components of cognitive control are differentially sensitive to ADHD. The ADHD children's inability to activate the caudate nucleus constitutes a core abnormality in ADHD. Observed functional abnormalities did not result from prolonged stimulant exposure, since most children were medication naive. PMID:16135618

  2. Differential brain activation to angry faces by elite warfighters: neural processing evidence for enhanced threat detection.

    Directory of Open Access Journals (Sweden)

    Martin P Paulus

    Full Text Available BACKGROUND: Little is known about the neural basis of elite performers and their optimal performance in extreme environments. The purpose of this study was to examine brain processing differences between elite warfighters and comparison subjects in brain structures that are important for emotion processing and interoception. METHODOLOGY/PRINCIPAL FINDINGS: Navy Sea, Air, and Land Forces (SEALs while off duty (n = 11 were compared with n = 23 healthy male volunteers while performing a simple emotion face-processing task during functional magnetic resonance imaging. Irrespective of the target emotion, elite warfighters relative to comparison subjects showed relatively greater right-sided insula, but attenuated left-sided insula, activation. Navy SEALs showed selectively greater activation to angry target faces relative to fearful or happy target faces bilaterally in the insula. This was not accounted for by contrasting positive versus negative emotions. Finally, these individuals also showed slower response latencies to fearful and happy target faces than did comparison subjects. CONCLUSIONS/SIGNIFICANCE: These findings support the hypothesis that elite warfighters deploy greater processing resources toward potential threat-related facial expressions and reduced processing resources to non-threat-related facial expressions. Moreover, rather than expending more effort in general, elite warfighters show more focused neural and performance tuning. In other words, greater neural processing resources are directed toward threat stimuli and processing resources are conserved when facing a nonthreat stimulus situation.

  3. The Athlete’s Brain: Cross-Sectional Evidence for Neural Efficiency during Cycling Exercise

    Directory of Open Access Journals (Sweden)

    Sebastian Ludyga

    2016-01-01

    Full Text Available The “neural efficiency” hypothesis suggests that experts are characterized by a more efficient cortical function in cognitive tests. Although this hypothesis has been extended to a variety of movement-related tasks within the last years, it is unclear whether or not neural efficiency is present in cyclists performing endurance exercise. Therefore, this study examined brain cortical activity at rest and during exercise between cyclists of higher (HIGH; n=14; 55.6 ± 2.8 mL/min/kg and lower (LOW; n=15; 46.4 ± 4.1 mL/min/kg maximal oxygen consumption (VO2MAX. Male and female participants performed a graded exercise test with spirometry to assess VO2MAX. After 3 to 5 days, EEG was recorded at rest with eyes closed and during cycling at the individual anaerobic threshold over a 30 min period. Possible differences in alpha/beta ratio as well as alpha and beta power were investigated at frontal, central, and parietal sites. The statistical analysis revealed significant differences between groups (F=12.04; p=0.002, as the alpha/beta ratio was increased in HIGH compared to LOW in both the resting state (p≤0.018 and the exercise condition (p≤0.025. The present results indicate enhanced neural efficiency in subjects with high VO2MAX, possibly due to the inhibition of task-irrelevant cognitive processes.

  4. The Athlete's Brain: Cross-Sectional Evidence for Neural Efficiency during Cycling Exercise.

    Science.gov (United States)

    Ludyga, Sebastian; Gronwald, Thomas; Hottenrott, Kuno

    2016-01-01

    The "neural efficiency" hypothesis suggests that experts are characterized by a more efficient cortical function in cognitive tests. Although this hypothesis has been extended to a variety of movement-related tasks within the last years, it is unclear whether or not neural efficiency is present in cyclists performing endurance exercise. Therefore, this study examined brain cortical activity at rest and during exercise between cyclists of higher (HIGH; n = 14; 55.6 ± 2.8 mL/min/kg) and lower (LOW; n = 15; 46.4 ± 4.1 mL/min/kg) maximal oxygen consumption (VO2MAX). Male and female participants performed a graded exercise test with spirometry to assess VO2MAX. After 3 to 5 days, EEG was recorded at rest with eyes closed and during cycling at the individual anaerobic threshold over a 30 min period. Possible differences in alpha/beta ratio as well as alpha and beta power were investigated at frontal, central, and parietal sites. The statistical analysis revealed significant differences between groups (F = 12.04; p = 0.002), as the alpha/beta ratio was increased in HIGH compared to LOW in both the resting state (p ≤ 0.018) and the exercise condition (p ≤ 0.025). The present results indicate enhanced neural efficiency in subjects with high VO2MAX, possibly due to the inhibition of task-irrelevant cognitive processes.

  5. What are they up to? The role of sensory evidence and prior knowledge in action understanding.

    Directory of Open Access Journals (Sweden)

    Valerian Chambon

    Full Text Available Explaining or predicting the behaviour of our conspecifics requires the ability to infer the intentions that motivate it. Such inferences are assumed to rely on two types of information: (1 the sensory information conveyed by movement kinematics and (2 the observer's prior expectations--acquired from past experience or derived from prior knowledge. However, the respective contribution of these two sources of information is still controversial. This controversy stems in part from the fact that "intention" is an umbrella term that may embrace various sub-types each being assigned different scopes and targets. We hypothesized that variations in the scope and target of intentions may account for variations in the contribution of visual kinematics and prior knowledge to the intention inference process. To test this hypothesis, we conducted four behavioural experiments in which participants were instructed to identify different types of intention: basic intentions (i.e. simple goal of a motor act, superordinate intentions (i.e. general goal of a sequence of motor acts, or social intentions (i.e. intentions accomplished in a context of reciprocal interaction. For each of the above-mentioned intentions, we varied (1 the amount of visual information available from the action scene and (2 participant's prior expectations concerning the intention that was more likely to be accomplished. First, we showed that intentional judgments depend on a consistent interaction between visual information and participant's prior expectations. Moreover, we demonstrated that this interaction varied according to the type of intention to be inferred, with participant's priors rather than perceptual evidence exerting a greater effect on the inference of social and superordinate intentions. The results are discussed by appealing to the specific properties of each type of intention considered and further interpreted in the light of a hierarchical model of action representation.

  6. Cross-linguistic differences in the neural representation of human language: evidence from users of signed languages.

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    Corina, David P; Lawyer, Laurel A; Cates, Deborah

    2012-01-01

    Studies of deaf individuals who are users of signed languages have provided profound insight into the neural representation of human language. Case studies of deaf signers who have incurred left- and right-hemisphere damage have shown that left-hemisphere resources are a necessary component of sign language processing. These data suggest that, despite frank differences in the input and output modality of language, core left perisylvian regions universally serve linguistic function. Neuroimaging studies of deaf signers have generally provided support for this claim. However, more fine-tuned studies of linguistic processing in deaf signers are beginning to show evidence of important differences in the representation of signed and spoken languages. In this paper, we provide a critical review of this literature and present compelling evidence for language-specific cortical representations in deaf signers. These data lend support to the claim that the neural representation of language may show substantive cross-linguistic differences. We discuss the theoretical implications of these findings with respect to an emerging understanding of the neurobiology of language.

  7. Cross-linguistic differences in the neural representation of human language: evidence from users of signed languages.

    Directory of Open Access Journals (Sweden)

    David eCorina

    2013-01-01

    Full Text Available Studies of deaf individuals who are users of signed languages have provided profound insight into the neural representation of human language. Case studies of deaf signers who have incurred left- and right-hemisphere damage have shown that left-hemisphere resources are a necessary component of sign language processing. These data suggest that, despite frank differences in the input and output modality of language,; core left perisylvian regions universally serve linguistic function. Neuroimaging studies of deaf signers have generally provided support for this claim. However, more fine-tuned studies of linguistic processing in deaf signers are beginning to show evidence of important differences in the representation of signed and spoken languages. In this paper, we provide a critical review of this literature and present compelling evidence for language-specific cortical representations in deaf signers. These data lend support to the claim that the neural representation of language may show substantive cross-linguistic differences. We discuss the theoretical implications of these findings with respect to an emerging understanding of the neurobiology of language.

  8. Nurse task shifting for antiretroviral treatment services in Namibia: implementation research to move evidence into action.

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    Gabrielle O'Malley

    Full Text Available BACKGROUND: Evidence from several sub-Saharan countries support nurse-initiated antiretroviral treatment as a feasible alternative to doctor-led models characteristic of early responses to the HIV epidemic. However, service delivery models shown to be effective in one country may not be readily adopted in another. This study used an implementation research approach to assist policy makers and other stakeholders to assess the acceptability and feasibility of task shifting in the Namibian context. METHODS: The Namibian Ministry of Health and Social Services implemented a Task Shifting Demonstration Project (TSDP at 9 sites at different levels of the health system. Six months after implementation, a mixed methods evaluation was conducted. Seventy semi-structured interviews were conducted with patients, managers, doctors and nurses directly involved with the TSDP. Physician-evaluators observed and compared health service provision between doctors and nurses for 40 patients (80 observations, documenting performance in agreement with the national guidelines on 13 clinical care indicators. RESULTS: Doctors, nurses, and patients interviewed believed task shifting would improve access to and quality of HIV services. Doctors and nurses both reported an increase in nurses' skills as a result of the project. Observation data showed doctors and nurses were in considerable agreement (>80% with each other on all dimensions of HIV care and ≥90% on eight dimensions. To ensure success of national scale-up of the task shifting model, challenges involving infrastructure, on-going mentoring, and nursing scope of practice should be anticipated and addressed. CONCLUSION: In combination with findings from other studies in the region, data from the TSDP provided critical and timely information to the Namibian Ministry of Health and Social Services, thus helping to move evidence into action. Small-scale implementation research projects enable stakeholders to learn by

  9. Neural mechanisms of human perceptual learning: electrophysiological evidence for a two-stage process.

    Science.gov (United States)

    Hamamé, Carlos M; Cosmelli, Diego; Henriquez, Rodrigo; Aboitiz, Francisco

    2011-04-26

    Humans and other animals change the way they perceive the world due to experience. This process has been labeled as perceptual learning, and implies that adult nervous systems can adaptively modify the way in which they process sensory stimulation. However, the mechanisms by which the brain modifies this capacity have not been sufficiently analyzed. We studied the neural mechanisms of human perceptual learning by combining electroencephalographic (EEG) recordings of brain activity and the assessment of psychophysical performance during training in a visual search task. All participants improved their perceptual performance as reflected by an increase in sensitivity (d') and a decrease in reaction time. The EEG signal was acquired throughout the entire experiment revealing amplitude increments, specific and unspecific to the trained stimulus, in event-related potential (ERP) components N2pc and P3 respectively. P3 unspecific modification can be related to context or task-based learning, while N2pc may be reflecting a more specific attentional-related boosting of target detection. Moreover, bell and U-shaped profiles of oscillatory brain activity in gamma (30-60 Hz) and alpha (8-14 Hz) frequency bands may suggest the existence of two phases for learning acquisition, which can be understood as distinctive optimization mechanisms in stimulus processing. We conclude that there are reorganizations in several neural processes that contribute differently to perceptual learning in a visual search task. We propose an integrative model of neural activity reorganization, whereby perceptual learning takes place as a two-stage phenomenon including perceptual, attentional and contextual processes.

  10. Neural mechanisms of human perceptual learning: electrophysiological evidence for a two-stage process.

    Directory of Open Access Journals (Sweden)

    Carlos M Hamamé

    Full Text Available BACKGROUND: Humans and other animals change the way they perceive the world due to experience. This process has been labeled as perceptual learning, and implies that adult nervous systems can adaptively modify the way in which they process sensory stimulation. However, the mechanisms by which the brain modifies this capacity have not been sufficiently analyzed. METHODOLOGY/PRINCIPAL FINDINGS: We studied the neural mechanisms of human perceptual learning by combining electroencephalographic (EEG recordings of brain activity and the assessment of psychophysical performance during training in a visual search task. All participants improved their perceptual performance as reflected by an increase in sensitivity (d' and a decrease in reaction time. The EEG signal was acquired throughout the entire experiment revealing amplitude increments, specific and unspecific to the trained stimulus, in event-related potential (ERP components N2pc and P3 respectively. P3 unspecific modification can be related to context or task-based learning, while N2pc may be reflecting a more specific attentional-related boosting of target detection. Moreover, bell and U-shaped profiles of oscillatory brain activity in gamma (30-60 Hz and alpha (8-14 Hz frequency bands may suggest the existence of two phases for learning acquisition, which can be understood as distinctive optimization mechanisms in stimulus processing. CONCLUSIONS/SIGNIFICANCE: We conclude that there are reorganizations in several neural processes that contribute differently to perceptual learning in a visual search task. We propose an integrative model of neural activity reorganization, whereby perceptual learning takes place as a two-stage phenomenon including perceptual, attentional and contextual processes.

  11. Is recursion language-specific? Evidence of recursive mechanisms in the structure of intentional action.

    Science.gov (United States)

    Vicari, Giuseppe; Adenzato, Mauro

    2014-05-01

    In their 2002 seminal paper Hauser, Chomsky and Fitch hypothesize that recursion is the only human-specific and language-specific mechanism of the faculty of language. While debate focused primarily on the meaning of recursion in the hypothesis and on the human-specific and syntax-specific character of recursion, the present work focuses on the claim that recursion is language-specific. We argue that there are recursive structures in the domain of motor intentionality by way of extending John R. Searle's analysis of intentional action. We then discuss evidence from cognitive science and neuroscience supporting the claim that motor-intentional recursion is language-independent and suggest some explanatory hypotheses: (1) linguistic recursion is embodied in sensory-motor processing; (2) linguistic and motor-intentional recursions are distinct and mutually independent mechanisms. Finally, we propose some reflections about the epistemic status of HCF as presenting an empirically falsifiable hypothesis, and on the possibility of testing recursion in different cognitive domains.

  12. Neural and Behavioral Evidence for an Online Resetting Process in Visual Working Memory.

    Science.gov (United States)

    Balaban, Halely; Luria, Roy

    2017-02-01

    Visual working memory (VWM) guides behavior by holding a set of active representations and modifying them according to changes in the environment. This updating process relies on a unique mapping between each VWM representation and an actual object in the environment. Here, we destroyed this mapping by either presenting a coherent object but then breaking it into independent parts or presenting an object but then abruptly replacing it with a different object. This allowed us to introduce the neural marker and behavioral consequence of an online resetting process in humans' VWM. Across seven experiments, we demonstrate that this resetting process involves abandoning the old VWM contents because they no longer correspond to the objects in the environment. Then, VWM encodes the novel information and reestablishes the correspondence between the new representations and the objects. The resetting process was marked by a unique neural signature: a sharp drop in the amplitude of the electrophysiological index of VWM contents (the contralateral delay activity), presumably indicating the loss of the existent object-to-representation mappings. This marker was missing when an updating process occurred. Moreover, when tracking moving items, VWM failed to detect salient changes in the object's shape when these changes occurred during the resetting process. This happened despite the object being fully visible, presumably because the mapping between the object and a VWM representation was lost. Importantly, we show that resetting, its neural marker, and the behavioral cost it entails, are specific to situations that involve a destruction of the objects-to-representations correspondence. Visual working memory (VWM) maintains task-relevant information in an online state. Previous studies showed that VWM representations are accessed and modified after changes in the environment. Here, we show that this updating process critically depends on an ongoing mapping between the

  13. Neural evidence for compromised motor imagery in right hemiparetic cerebral palsy

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    Michiel Van Elk

    2010-11-01

    Full Text Available In the present EEG study we investigated the neural and temporal dynamics of motor imagery in participants with right-sided HCP (n = 10 and in left-handed control participants (n = 10. A mental rotation task was used in which participants were required to judge the laterality of hand pictures. At a behavioral level participants with HCP were slower in making hand laterality judgments compared to control subjects, especially when presented with pictures representing the affected hand. At a neural level, individuals with HCP were characterized by a reduced rotation-related negativity (RRN over parietal areas, that was delayed in onset with respect to control participants. Interestingly, participants that were relatively mildly impaired showed a stronger RRN for the rotation of right hand stimuli than participants that were more strongly impaired in their motor function, suggesting a direct relation between the motor imagery process and the biomechanical constraints of the participant. Together, the results provide new insights in the relation between motor imagery and motor capabilities and indicate that participants with HCP may be characterized by a compromised ability to use motor imagery.

  14. Development of social skills in children: neural and behavioral evidence for the elaboration of cognitive models

    Science.gov (United States)

    Soto-Icaza, Patricia; Aboitiz, Francisco; Billeke, Pablo

    2015-01-01

    Social skills refer to a wide group of abilities that allow us to interact and communicate with others. Children learn how to solve social situations by predicting and understanding other's behaviors. The way in which humans learn to interact successfully with others encompasses a complex interaction between neural, behavioral, and environmental elements. These have a role in the accomplishment of positive developmental outcomes, including peer acceptance, academic achievement, and mental health. All these social abilities depend on widespread brain networks that are recently being studied by neuroscience. In this paper, we will first review the studies on this topic, aiming to clarify the behavioral and neural mechanisms related to the acquisition of social skills during infancy and their appearance in time. Second, we will briefly describe how developmental diseases like Autism Spectrum Disorders (ASD) can inform about the neurobiological mechanisms of social skills. We finally sketch a general framework for the elaboration of cognitive models in order to facilitate the comprehension of human social development. PMID:26483621

  15. Development of social skills in children: neural and behavioral evidence for the elaboration of cognitive models.

    Science.gov (United States)

    Soto-Icaza, Patricia; Aboitiz, Francisco; Billeke, Pablo

    2015-01-01

    Social skills refer to a wide group of abilities that allow us to interact and communicate with others. Children learn how to solve social situations by predicting and understanding other's behaviors. The way in which humans learn to interact successfully with others encompasses a complex interaction between neural, behavioral, and environmental elements. These have a role in the accomplishment of positive developmental outcomes, including peer acceptance, academic achievement, and mental health. All these social abilities depend on widespread brain networks that are recently being studied by neuroscience. In this paper, we will first review the studies on this topic, aiming to clarify the behavioral and neural mechanisms related to the acquisition of social skills during infancy and their appearance in time. Second, we will briefly describe how developmental diseases like Autism Spectrum Disorders (ASD) can inform about the neurobiological mechanisms of social skills. We finally sketch a general framework for the elaboration of cognitive models in order to facilitate the comprehension of human social development.

  16. Neural evidence for a 3-state model of visual short-term memory.

    Science.gov (United States)

    Nee, Derek Evan; Jonides, John

    2013-07-01

    Recent research has suggested that short-term memory (STM) can be partitioned into three distinct states. By this model, a single item is held in the focus of attention making it available for immediate processing (focus of attention), a capacity-limited set of additional items is actively maintained for future processing (direct access region), and other recently presented information is passively active, but can nevertheless influence ongoing cognition (activated portion of long-term memory). While there is both behavioral and neural support for this 3-state model in verbal STM, it is unclear whether the model generalizes to non-verbal STM. Here, we tested a 3-state model of visual STM using fMRI. We found a triple dissociation of regions involved in the access of each hypothesized state. The inferior parietal cortex mediated access to the focus of attention, the medial temporal lobe (MTL) including the hippocampus mediated access to the direct access region, and the left ventrolateral prefrontal cortex (VLPFC) mediated access to the activated portion of long-term memory. Direct comparison with previously collected verbal STM data revealed overlapping neural activations involved in the access of each state across different forms of content suggesting that mechanisms of access are domain general. These data support a 3-state model of STM.

  17. Evidence-Based Practice and Teacher Action-Research: A Reflection on the Nature and Direction of "Change"

    Science.gov (United States)

    Colucci-Gray, Laura; Das, Sharmistha; Gray, Donald; Robson, Dean; Spratt, Jennifer

    2013-01-01

    This study was conceived as an opportunity to reflect on the place of action-research in the contested landscape of educational change in the UK where increasing emphasis has been put on the use of evidence to drive reform. In the context of a government-sponsored project in Scotland, this study looked at the impact of a scholarship initiative…

  18. Systematic implementation of evidence-based practice in a clinical nursing setting : a participatory action research project

    NARCIS (Netherlands)

    Friesen-Storms, Jolanda; Moser, Albine; Loo, Sandra van der; Beurskens, Anna; Bours, Gerrie

    2015-01-01

    Aims and objectives: To describe the process of implementing evidence-based practice (EBP) in a clinical nursing setting. Background: EBP has become a major issue in nursing, it is insufficiently integrated in daily practice and its implementation is complex. Design: Participatory action researc

  19. Analytics4Action Evaluation Framework: A Review of Evidence-Based Learning Analytics Interventions at the Open University UK

    Science.gov (United States)

    Rienties, Bart; Boroowa, Avinash; Cross, Simon; Kubiak, Chris; Mayles, Kevin; Murphy, Sam

    2016-01-01

    There is an urgent need to develop an evidence-based framework for learning analytics whereby stakeholders can manage, evaluate, and make decisions about which types of interventions work well and under which conditions. In this article, we will work towards developing a foundation of an Analytics4Action Evaluation Framework (A4AEF) that is…

  20. From evidence to action to deliver a healthy start for the next generation.

    Science.gov (United States)

    Mason, Elizabeth; McDougall, Lori; Lawn, Joy E; Gupta, Anuradha; Claeson, Mariam; Pillay, Yogan; Presern, Carole; Lukong, Martina Baye; Mann, Gillian; Wijnroks, Marijke; Azad, Kishwar; Taylor, Katherine; Beattie, Allison; Bhutta, Zulfiqar A; Chopra, Mickey

    2014-08-01

    attention to increasing of health worker numbers and skills with attention to high-quality childbirth care for newborn babies as well as mothers and children; and (5) evaluation, tracking coverage of priority interventions and packages of care with clear accountability to accelerate progress and reach the poorest groups. The Every Newborn Action Plan provides an evidence-based roadmap towards care for every woman, and a healthy start for every newborn baby, with a right to be counted, survive, and thrive wherever they are born.

  1. How treatment affects the brain: meta-analysis evidence of neural substrates underpinning drug therapy and psychotherapy in major depression.

    Science.gov (United States)

    Boccia, Maddalena; Piccardi, Laura; Guariglia, Paola

    2016-06-01

    The idea that modifications of affect, behavior and cognition produced by psychotherapy are mediated by biological underpinnings predates the advent of the modern neurosciences. Recently, several studies demonstrated that psychotherapy outcomes are linked to modifications in specific brain regions. This opened the debate over the similarities and dissimilarities between psychotherapy and pharmacotherapy. In this study, we used activation likelihood estimation meta-analysis to investigate the effects of psychotherapy (PsyTh) and pharmacotherapy (DrugTh) on brain functioning in Major Depression (MD). Our results demonstrate that the two therapies modify different neural circuits. Specifically, PsyTh induces selective modifications in the left inferior and superior frontal gyri, middle temporal gyrus, lingual gyrus and middle cingulate cortex, as well as in the right middle frontal gyrus and precentral gyrus. Otherwise, DrugTh selectively affected brain activation in the right insula in MD patients. These results are in line with previous evidence of the synergy between psychotherapy and pharmacotherapy but they also demonstrate that the two therapies have different neural underpinnings.

  2. Electroencephalogram evidence for the activation of human mirror neuron system during the observation of intransitive shadow and line drawing actions

    Institute of Scientific and Technical Information of China (English)

    Huaping Zhu; Yaoru Sun; Fang Wang

    2013-01-01

    Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system during the observation of intransitive movements by shadows and line drawings of hands. This study examined the suppression of electroencephalography mu waves hand actions, hand shadow actions and actions made by line drawings of hands. The results showed significant desynchronization of the mu rhythm ("mu suppression") across the sensorimotor cortex (recorded at C3, Cz and C4), the frontal cortex (recorded at F3, Fz and F4) and the central and right posterior parietal cortex (recorded at Pz and P4) under all three conditions. Our experimental findings suggest that the observation of "impoverished hand actions", such as intransitive movements of shadows and line drawings of hands, is able to activate widespread cortical areas related to the putative human mirror neuron system.

  3. Neural correlates of "feeling-of-not-knowing":Evidence from functional MRI

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The neural correlates of "feeling-of-not- knowing" ("FOnK", i.e. the feeling-of-knowing judgments that accurately predicted "not knowing" or "misses" in the criterion test) were investigated by the event-related fMRI method through an RJR (recall-judgment-recognition) procedure that adopted unrelated word pairs as materials. Results revealed that, relative to the inaccurate "FOnK" predictions, the accurate ones were associated with activities in right ventral prefrontal cortex (PFC) and insula, the areas that were known to subserve "cue specification" in which the retrieval cues were converted into "descriptors" that could be used for direct memory search. This result implied that the accurate "FOnK" predictions relayed more on "cue specification" process than the inaccurate ones and was in consistent with the cue familiarity heuristic hypothesis of feeling-of-knowing.

  4. Neural evidence reveals the rapid effects of reward history on selective attention.

    Science.gov (United States)

    MacLean, Mary H; Giesbrecht, Barry

    2015-05-05

    Selective attention is often framed as being primarily driven by two factors: task-relevance and physical salience. However, factors like selection and reward history, which are neither currently task-relevant nor physically salient, can reliably and persistently influence visual selective attention. The current study investigated the nature of the persistent effects of irrelevant, physically non-salient, reward-associated features. These features affected one of the earliest reliable neural indicators of visual selective attention in humans, the P1 event-related potential, measured one week after the reward associations were learned. However, the effects of reward history were moderated by current task demands. The modulation of visually evoked activity supports the hypothesis that reward history influences the innate salience of reward associated features, such that even when no longer relevant, nor physically salient, these features have a rapid, persistent, and robust effect on early visual selective attention.

  5. COGNITIVE LEARNING OF INTELLIGENCE SYSTEMS USING NEURAL NETWORKS: EVIDENCE FROM THE AUSTRALIAN CAPITAL MARKETS

    Directory of Open Access Journals (Sweden)

    Joachim Tan

    2002-01-01

    Full Text Available Artificial neural networks (ANNs allow users to improve forecasts through pattern recognition. The purpose of this paper is to validate ANNs as a detection tool in four financial markets. This study investigates whether market inefficiencies exist using ANN as a model. It also investigates whether additional publicly available information can provide investors with a trading advantage. In finance, any forecasting advantage obtained through the use of publicly available information albeit internal or/and external market factors suggest inefficiencies in the financial markets. In this paper, we explore the efficiency of the United States, Japan, Hong Kong and Australia. In Australia, using the ASX 200 index, we demonstrate how the inclusion of external information to our ANN improves our forecasting. Our results show accounting for external market signals significantly improves forecasts of the ASX200 index by an additional 10 percent. This suggests the inclusion of publicly available information from other markets, can improve predictions and returns for investors.

  6. Neural correlates of the popular music phenomenon: evidence from functional MRI and PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qiaozhen [The Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Psychiatry, Hangzhou (China); Zhejiang University Medical PET Center, Hangzhou (China); Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou (China); Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou (China); The Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Nuclear Medicine, Hangzhou, Zhejiang (China); Zhang, Ying; Hou, Haifeng; Du, Fenglei; Wu, Shuang; Chen, Lin; Shen, Yehua; Chao, Fangfang; Zhang, Hong; Tian, Mei [Zhejiang University Medical PET Center, Hangzhou (China); Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou (China); Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou (China); The Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Nuclear Medicine, Hangzhou, Zhejiang (China); Chung, June-key [Seoul National University Hospital, Department of Nuclear Medicine, Seoul (Korea, Republic of)

    2017-06-15

    Music can induce different emotions. However, its neural mechanism remains unknown. The aim of this study was to use functional magnetic resonance imaging (fMRI) and position emission tomography (PET) imaging for mapping of neural changes under the most popular music in healthy volunteers. Blood-oxygen-level-dependent (BOLD) fMRI and monoamine receptor PET imaging with {sup 11}C-N-methylspiperone ({sup 11}C-NMSP) were conducted under the popular music Gangnam Style and light music A Comme Amour in healthy subjects. PET and fMRI images were analyzed by using the Statistical Parametric Mapping software (SPM). Significantly increased fMRI BOLD signals were found in the bilateral superior temporal cortices, left cerebellum, left putamen and right thalamus cortex. Monoamine receptor availability was increased significantly in the left superior temporal gyrus and left putamen, but decreased in the bilateral superior occipital cortices under the Gangnam Style compared with the light music condition. Significant positive correlation was found between {sup 11}C-NMSP binding and fMRI BOLD signals in the left temporal cortex. Furthermore, increased {sup 11}C-NMSP binding in the left putamen was positively correlated with the mood arousal level score under the Gangnam Style condition. Popular music Gangnam Style can arouse pleasure experience and strong emotional response. The left putamen is positively correlated with the mood arousal level score under the Gangnam Style condition. Our results revealed characteristic patterns of brain activity associated with Gangnam Style, and may also provide more general insights into the music-induced emotional processing. (orig.)

  7. Mechanisms of action of spa therapies in rheumatic diseases: what scientific evidence is there?

    Science.gov (United States)

    Fioravanti, Antonella; Cantarini, Luca; Guidelli, Giacomo Maria; Galeazzi, Mauro

    2011-01-01

    Spa therapy represents a popular treatment for many rheumatic diseases. The mechanisms by which immersion in mineral or thermal water or the application of mud alleviates suffering in rheumatic diseases are not fully understood. The net benefit is probably the result of a combination of factors, with mechanical, thermal and chemical effects among the most prominent ones. Buoyancy, immersion, resistance and temperature all play important roles. According to the gate theory, pain relief may be due to the pressure and temperature of the water on skin; hot stimuli may influence muscle tone and pain intensity, helping to reduce muscle spasm and to increase the pain threshold. Mud-bath therapy increases plasma β-endorphin levels and secretion of corticotrophin, cortisol, growth hormone and prolactin. It has recently been demonstrated that thermal mud-pack therapy induces a reduction in the circulating levels of prostaglandin E2 (PGE2), leukotriene B4 (LTB4), interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α), important mediators of inflammation and pain. Spa therapy has been found to cause an increase in insulin-like growth factor-1 (IGF1), which stimulates cartilage metabolism, and transforming growth factor-β (TGF-β). There is also evidence of the positive action of mud-packs and thermal baths on the oxidant/antioxidant system, with a reduction in the release of reactive oxygen (ROS) and nitrogen (RNS) species. Overall, thermal stress has an immunosuppressive effect. Many other non-specific factors may also contribute to the beneficial effects observed after spa therapy in some rheumatic diseases, including effects on cardiovascular risk factors, and changes in the environment, pleasant surroundings and the absence of work duties.

  8. Active vision during action execution, observation and imagery: evidence for shared motor representations.

    Directory of Open Access Journals (Sweden)

    Sheree A McCormick

    Full Text Available The concept of shared motor representations between action execution and various covert conditions has been demonstrated through a number of psychophysiological modalities over the past two decades. Rarely, however, have researchers considered the congruence of physical, imaginary and observed movement markers in a single paradigm and never in a design where eye movement metrics are the markers. In this study, participants were required to perform a forward reach and point Fitts' Task on a digitizing tablet whilst wearing an eye movement system. Gaze metrics were used to compare behaviour congruence between action execution, action observation, and guided and unguided movement imagery conditions. The data showed that participants attended the same task-related visual cues between conditions but the strategy was different. Specifically, the number of fixations was significantly different between action execution and all covert conditions. In addition, fixation duration was congruent between action execution and action observation only, and both conditions displayed an indirect Fitts' Law effect. We therefore extend the understanding of the common motor representation by demonstrating, for the first time, common spatial eye movement metrics across simulation conditions and some specific temporal congruence for action execution and action observation. Our findings suggest that action observation may be an effective technique in supporting motor processes. The use of video as an adjunct to physical techniques may be beneficial in supporting motor planning in both performance and clinical rehabilitation environments.

  9. Motor-related brain activity during action observation: a neural substrate for electrocorticographic brain-computer interfaces after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Jennifer L Collinger

    2014-02-01

    Full Text Available After spinal cord injury (SCI, motor commands from the brain are unable to reach peripheral nerves and muscles below the level of the lesion. Action observation, in which a person observes someone else performing an action, has been used to augment traditional rehabilitation paradigms. Similarly, action observation can be used to derive the relationship between brain activity and movement kinematics for a motor-based brain-computer interface (BCI even when the user cannot generate overt movements. BCIs use brain signals to control external devices to replace functions that have been lost due to SCI or other motor impairment. Previous studies have reported congruent motor cortical activity during observed and overt movements using magnetoencephalography (MEG and functional magnetic resonance imaging (fMRI. Recent single-unit studies using intracortical microelectrodes also demonstrated that a large number of motor cortical neurons had similar firing rate patterns between overt and observed movements. Given the increasing interest in electrocorticography (ECoG-based BCIs, our goal was to identify whether action observation-related cortical activity could be recorded using ECoG during grasping tasks. Specifically, we aimed to identify congruent neural activity during observed and executed movements in both the sensorimotor rhythm (10-40 Hz and the high-gamma band (65-115 Hz which contains significant movement-related information. We observed significant motor-related high-gamma band activity during action observation in both able-bodied individuals and one participant with a complete C4 SCI. Furthermore, in able-bodied participants, both the low and high frequency bands demonstrated congruent activity between action execution and observation. Our results suggest that action observation could be an effective and critical procedure for deriving the mapping from ECoG signals to intended movement for an ECoG-based BCI system for individuals with

  10. Erythropoietin modulates neural and cognitive processing of emotional information in biomarker models of antidepressant drug action in depressed patients

    DEFF Research Database (Denmark)

    Miskowiak, Kamilla W; Favaron, Elisa; Hafizi, Sepehr

    2010-01-01

    Erythropoietin (Epo) has neuroprotective and neurotrophic effects, and may be a novel therapeutic agent in the treatment of psychiatric disorders. We have demonstrated antidepressant-like effects of Epo on the neural and cognitive processing of facial expressions in healthy volunteers. The curren...

  11. Affirmative Action in Education: Evidence From Engineering College Admissions in India. NBER Working Paper No. 13926

    Science.gov (United States)

    Bertrand, Marianne; Hanna, Rema; Mullainathan, Sendhil

    2008-01-01

    Many countries mandate affirmative action in university admissions for traditionally disadvantaged groups. Little is known about either the efficacy or costs of these programs. This paper examines affirmative action in engineering colleges in India for "lower-caste" groups. We find that it successfully targets the financially…

  12. Pupillometric evidence for the locus coeruleus-noradrenaline system facilitating attentional processing of action-triggered visual stimuli.

    Science.gov (United States)

    Kihara, Ken; Takeuchi, Tatsuto; Yoshimoto, Sanae; Kondo, Hirohito M; Kawahara, Jun I

    2015-01-01

    It has been argued that attentional processing of visual stimuli is facilitated by a voluntary action that triggers the stimulus onset. However, the relationship between action-induced facilitation of attention and the neural substrates has not been well established. The present study investigated whether the locus coeruleus-noradrenaline (LC-NA) system is involved in this facilitation effect. A rapid serial visual presentation paradigm was used to assess the dynamics of transient attention in humans. Participants were instructed to change a digit stream to a letter stream by pressing a button and specifying successive targets of four letters. Pupil dilation was measured as an index of LC-NA function. Accuracy of target identification was better when the temporal delay between participants' key press and target onset was 800 ms than when targets appeared just after the key press or when targets appeared without key press. Accuracy of target identification was positively correlated with both the peak amplitude of pupil dilation and the pupil size at the time of the key press. These results indicate that target identification in the visual task is closely linked to pupil dilation. We conclude that the LC-NA system plays an important role in the facilitation of transient attention driven by voluntary action.

  13. Pupillometric evidence for the locus coeruleus-noradrenaline system facilitating attentional processing of action-triggered visual stimuli

    Directory of Open Access Journals (Sweden)

    Ken eKihara

    2015-06-01

    Full Text Available It has been argued that attentional processing of visual stimuli is facilitated by a voluntary action that triggers the stimulus onset. However, the relationship between action-induced facilitation of attention and the neural substrates has not been well established. The present study investigated whether the locus coeruleus-noradrenaline (LC-NA system is involved in this facilitation effect. A rapid serial visual presentation paradigm was used to assess the dynamics of transient attention in humans. Participants were instructed to change a digit stream to a letter stream by pressing a button and specifying successive targets of four letters. Pupil dilation was measured as an index of LC-NA function. Accuracy of target identification was better when the temporal delay between participants' key press and target onset was 800 ms than when targets appeared just after the key press or when targets appeared without key press. Accuracy of target identification was positively correlated with both the peak amplitude of pupil dilation and the pupil size at the time of the key press. These results indicate that target identification in the visual task is closely linked to pupil dilation. We conclude that the LC-NA system plays an important role in the facilitation of transient attention driven by voluntary action.

  14. Transfer of training from one working memory task to another: Behavioural and neural evidence

    Directory of Open Access Journals (Sweden)

    Erin L. Beatty

    2015-06-01

    Full Text Available N-back working memory (WM tasks necessitate the maintenance and updating of dynamic rehearsal sets during performance. The delayed matching-to-sample (dMTS task is another WM task, which in turn involves the encoding, maintenance, and retrieval of stimulus representations in sequential order. Because both n-back and dMTS engage WM function, we hypothesized that compared to a control task not taxing WM, training on the n-back task would be associated with better performance on dMTS by virtue of training a shared mental capacity. We tested this hypothesis by randomly assigning subjects (N = 43 to train on either the n-back (including 2-back and 3-back levels or an active control task. Following training, dMTS was administered in the fMRI scanner. The n-back group performed marginally better than the active control group on dMTS. In addition, although the n-back group improved more on the less difficult 2-back level than the more difficult 3-back level across training sessions, it was improvement on the 3-back level that accounted for 21% of the variance in dMTS performance. For the control group, improvement in training across sessions was unrelated to dMTS performance. At the neural level, greater activation in the left inferior frontal gyrus, right posterior parietal cortex and the cerebellum distinguished the n-back group from the control group in the maintenance phase of dMTS. Degree of improvement on the 3-back level across training sessions was correlated with activation in right lateral prefrontal and motor cortices in the maintenance phase of dMTS. Our results suggest that although n-back training is more likely to improve performance in easier blocks, it is improvement in more difficult blocks that is predictive of performance on a target task drawing on WM. In addition, the extent to which training on a task can transfer to another task is likely due to the engagement of shared cognitive capacities and underlying neural substrates

  15. Erroneous and correct actions have a different affective valence: evidence from ERPs.

    Science.gov (United States)

    Aarts, Kristien; De Houwer, Jan; Pourtois, Gilles

    2013-10-01

    The accuracy of actions is swiftly determined through specific monitoring brain systems. Event-related potential (ERP) studies have shown that error commission is associated with the generation of the error-related negativity (ERN/Ne), whereas correct actions are associated with the correct-related negativity (CRN). Although the exact functional meaning of the ERN/Ne (and CRN) component remains debated, some authors have suggested that it reflects the processing of the emotional significance of actions. However, no study to date has directly linked amplitude changes at the level of the ERN/Ne-CRN to the affective processing of actions. To decode the emotional valence of actions performed during a go/no-go task, the authors used an evaluative priming method in this study. After each action following the go/no-go stimulus, participants had to categorize an evaluative word as either positive or negative. Behavioral results showed that response errors (i.e., false alarms, FAs) performed during the go/no-go task led to a faster categorization of negative than positive words. Remarkably, this evaluative priming effect was related to the magnitude of the ERN/Ne component generated during the go/no-go task. Moreover, ERP results showed that the processing of evaluative words following FAs was influenced early on after word onset (early posterior negativity-EPN effect), while it was influenced later following correct as well as incorrect actions (late positive potential-LPP effect). Altogether, these ERP results suggest that the action-related ERN-CRN component encodes the perceived emotional significance of actions, such that early stages of evaluative word processing following these actions are influenced by this automatic process.

  16. The price of your soul: neural evidence for the non-utilitarian representation of sacred values.

    Science.gov (United States)

    Berns, Gregory S; Bell, Emily; Capra, C Monica; Prietula, Michael J; Moore, Sara; Anderson, Brittany; Ginges, Jeremy; Atran, Scott

    2012-03-05

    Sacred values, such as those associated with religious or ethnic identity, underlie many important individual and group decisions in life, and individuals typically resist attempts to trade off their sacred values in exchange for material benefits. Deontological theory suggests that sacred values are processed based on rights and wrongs irrespective of outcomes, while utilitarian theory suggests that they are processed based on costs and benefits of potential outcomes, but which mode of processing an individual naturally uses is unknown. The study of decisions over sacred values is difficult because outcomes cannot typically be realized in a laboratory, and hence little is known about the neural representation and processing of sacred values. We used an experimental paradigm that used integrity as a proxy for sacredness and which paid real money to induce individuals to sell their personal values. Using functional magnetic resonance imaging (fMRI), we found that values that people refused to sell (sacred values) were associated with increased activity in the left temporoparietal junction and ventrolateral prefrontal cortex, regions previously associated with semantic rule retrieval. This suggests that sacred values affect behaviour through the retrieval and processing of deontic rules and not through a utilitarian evaluation of costs and benefits.

  17. Neural evidence of allophonic perception in children at risk for dyslexia.

    Science.gov (United States)

    Noordenbos, M W; Segers, E; Serniclaes, W; Mitterer, H; Verhoeven, L

    2012-07-01

    Learning to read is a complex process that develops normally in the majority of children and requires the mapping of graphemes to their corresponding phonemes. Problems with the mapping process nevertheless occur in about 5% of the population and are typically attributed to poor phonological representations, which are--in turn--attributed to underlying speech processing difficulties. We examined auditory discrimination of speech sounds in 6-year-old beginning readers with a familial risk of dyslexia (n=31) and no such risk (n=30) using the mismatch negativity (MMN). MMNs were recorded for stimuli belonging to either the same phoneme category (acoustic variants of /bə/) or different phoneme categories (/bə/ vs. /də/). Stimuli from different phoneme categories elicited MMNs in both the control and at-risk children, but the MMN amplitude was clearly lower in the at-risk children. In contrast, the stimuli from the same phoneme category elicited an MMN in only the children at risk for dyslexia. These results show children at risk for dyslexia to be sensitive to acoustic properties that are irrelevant in their language. Our findings thus suggest a possible cause of dyslexia in that they show 6-year-old beginning readers with at least one parent diagnosed with dyslexia to have a neural sensitivity to speech contrasts that are irrelevant in the ambient language. This sensitivity clearly hampers the development of stable phonological representations and thus leads to significant reading impairment later in life.

  18. Neural Bases of Unconscious Error Detection in a Chinese Anagram Solution Task: Evidence from ERP Study.

    Directory of Open Access Journals (Sweden)

    Hua-Zhan Yin

    Full Text Available In everyday life, error monitoring and processing are important for improving ongoing performance in response to a changing environment. However, detecting an error is not always a conscious process. The temporal activation patterns of brain areas related to cognitive control in the absence of conscious awareness of an error remain unknown. In the present study, event-related potentials (ERPs in the brain were used to explore the neural bases of unconscious error detection when subjects solved a Chinese anagram task. Our ERP data showed that the unconscious error detection (UED response elicited a more negative ERP component (N2 than did no error (NE and detect error (DE responses in the 300-400-ms time window, and the DE elicited a greater late positive component (LPC than did the UED and NE in the 900-1200-ms time window after the onset of the anagram stimuli. Taken together with the results of dipole source analysis, the N2 (anterior cingulate cortex might reflect unconscious/automatic conflict monitoring, and the LPC (superior/medial frontal gyrus might reflect conscious error recognition.

  19. Neural evidence for enhanced attention to mistakes among school-aged children with a growth mindset

    Directory of Open Access Journals (Sweden)

    Hans S. Schroder

    2017-04-01

    Full Text Available Individuals who believe intelligence is malleable (a growth mindset are better able to bounce back from failures than those who believe intelligence is immutable. Event-related potential (ERP studies among adults suggest this resilience is related to increased attention allocation to errors. Whether this mechanism is present among young children remains unknown, however. We therefore evaluated error-monitoring ERPs among 123 school-aged children while they completed a child-friendly go/no-go task. As expected, higher attention allocation to errors (indexed by larger error positivity, Pe predicted higher post-error accuracy. Moreover, replicating adult work, growth mindset was related to greater attention to mistakes (larger Pe and higher post-error accuracy. Exploratory moderation analyses revealed that growth mindset increased post-error accuracy for children who did not attend to their errors. Together, these results demonstrate the combined role of growth mindset and neural mechanisms of attention allocation in bouncing back after failure among young children.

  20. Neural evidence for enhanced attention to mistakes among school-aged children with a growth mindset.

    Science.gov (United States)

    Schroder, Hans S; Fisher, Megan E; Lin, Yanli; Lo, Sharon L; Danovitch, Judith H; Moser, Jason S

    2017-04-01

    Individuals who believe intelligence is malleable (a growth mindset) are better able to bounce back from failures than those who believe intelligence is immutable. Event-related potential (ERP) studies among adults suggest this resilience is related to increased attention allocation to errors. Whether this mechanism is present among young children remains unknown, however. We therefore evaluated error-monitoring ERPs among 123 school-aged children while they completed a child-friendly go/no-go task. As expected, higher attention allocation to errors (indexed by larger error positivity, Pe) predicted higher post-error accuracy. Moreover, replicating adult work, growth mindset was related to greater attention to mistakes (larger Pe) and higher post-error accuracy. Exploratory moderation analyses revealed that growth mindset increased post-error accuracy for children who did not attend to their errors. Together, these results demonstrate the combined role of growth mindset and neural mechanisms of attention allocation in bouncing back after failure among young children. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Neural evidence for the subliminal processing of facial trustworthiness in infancy.

    Science.gov (United States)

    Jessen, Sarah; Grossmann, Tobias

    2017-04-22

    Face evaluation is thought to play a vital role in human social interactions. One prominent aspect is the evaluation of facial signs of trustworthiness, which has been shown to occur reliably, rapidly, and without conscious awareness in adults. Recent developmental work indicates that the sensitivity to facial trustworthiness has early ontogenetic origins as it can already be observed in infancy. However, it is unclear whether infants' sensitivity to facial signs of trustworthiness relies upon conscious processing of a face or, similar to adults, occurs also in response to subliminal faces. To investigate this question, we conducted an event-related brain potential (ERP) study, in which we presented 7-month-old infants with faces varying in trustworthiness. Facial stimuli were presented subliminally (below infants' face visibility threshold) for only 50ms and then masked by presenting a scrambled face image. Our data revealed that infants' ERP responses to subliminally presented faces differed as a function of trustworthiness. Specifically, untrustworthy faces elicited an enhanced negative slow wave (800-1000ms) at frontal and central electrodes. The current findings critically extend prior work by showing that, similar to adults, infants' neural detection of facial signs of trustworthiness occurs also in response to subliminal face. This supports the view that detecting facial trustworthiness is an early developing and automatic process in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Neural signatures of third-party punishment: evidence from penetrating traumatic brain injury.

    Science.gov (United States)

    Glass, Leila; Moody, Lara; Grafman, Jordan; Krueger, Frank

    2016-02-01

    The ability to survive within a cooperative society depends on impartial third-party punishment (TPP) of social norm violations. Two cognitive mechanisms have been postulated as necessary for the successful completion of TPP: evaluation of legal responsibility and selection of a suitable punishment given the magnitude of the crime. Converging neuroimaging research suggests two supporting domain-general networks; a mentalizing network for evaluation of legal responsibility and a central-executive network for determination of punishment. A whole-brain voxel-based lesion-symptom mapping approach was used in conjunction with a rank-order TPP task to identify brain regions necessary for TPP in a large sample of patients with penetrating traumatic brain injury. Patients who demonstrated atypical TPP had specific lesions in core regions of the mentalizing (dorsomedial prefrontal cortex [PFC], ventromedial PFC) and central-executive (bilateral dorsolateral PFC, right intraparietal sulcus) networks. Altruism and executive functioning (concept formation skills) were significant predictors of TPP: altruism was uniquely associated with TPP in patients with lesions in right dorsolateral PFC and executive functioning was uniquely associated with TPP in individuals with lesions in left PFC. Our findings contribute to the extant literature to support underlying neural networks associated with TPP, with specific brain-behavior causal relationships confirming recent functional neuroimaging research.

  3. The functional neuroanatomy of actions.

    Science.gov (United States)

    Watson, Christine E; Chatterjee, Anjan

    2011-04-19

    Our current understanding of the neural basis of semantic memory is informed primarily by studies of concrete objects. However, conceptual knowledge encompasses many other, albeit less concrete, domains. This article reviews evidence from neuroimaging and patient studies that speaks to the neural basis of action concepts and the words that refer to them. These data highlight 2 important principles governing the neural instantiation of semantic knowledge. First, the organization of conceptual representations in the brain parallels perception and action. Action concepts are at least partially represented within modality-specific areas responsible for the perception and execution of dynamic actions. Second, unimodal sensory and motor cortices act as "points of entry" for more abstract action knowledge. Increasingly abstract conceptual knowledge derived from these modalities is represented in brain areas located anterior and centripetal to modality-specific regions. Extending research on the neural basis of semantics to include dynamic and relational aspects of the world gives us a more complete appreciation of the range of cognitive and communication impairments that may be experienced by patients with neurologic disease.

  4. A quantitative weight of evidence assessment of confidence in modes-of-action and their human relevance.

    Science.gov (United States)

    Dekant, Wolfgang; Bridges, James; Scialli, Anthony R

    2017-08-22

    A quantitative weight of evidence (QWoE) methodology was developed to assess confidence in postulated mode(s) of action for adverse effects in animal toxicity studies. The QWoE is appropriate for assessing adverse effects as relevant endpoints for classification and labeling purposes. The methodology involves definition of mode of actions and scoring supporting data for all key steps using predefined criteria for quality and relevance/strength of effects. Scores for all key steps are summarized, and the summary score is compared to the maximal achievable score for the mode of action. The ratio of the summary score to the maximal achievable scores gives an indication of confidence in a specific mode of action in animals. The mode of action in animals with highest confidence is then taken forward to assess appropriateness to humans. If one of the key steps cannot occur in humans, the mode of action is not relevant to humans. The methodology developed is applied to four case studies. Copyright © 2017. Published by Elsevier Inc.

  5. Dopaminergic modulation of positive expectations for goal-directed action: evidence from Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Noham eWolpe

    2015-10-01

    Full Text Available Parkinson’s disease (PD impairs the control of movement and cognition, including the planning of action and its consequences. This provides the opportunity to study the dopaminergic influences on the perception and awareness of action. Here we examined the perception of the outcome of a goal-directed action made by medicated patients with PD. A visuomotor task probed the integration of sensorimotor signals with the positive expectations of outcomes (Self priors, which in healthy adults bias perception towards success in proportion to trait optimism. We tested the hypotheses that (i the priors on the perception of the consequences of one’s own actions differ between patients and age- and sex-matched controls, and (ii that these priors are modulated by the levodopa dose equivalent in patients. There was no overall difference between patients and controls in the perceptual priors used. However, the precision of patient priors was inversely related to their levodopa dose equivalent. Patients with high levodopa dose equivalent showed more accurate priors, representing predictions that were closer to the true distribution of performance. Such accuracy has previously been demonstrated when observing the actions of others, suggesting abnormal awareness of action in these patients. These results confirm a link between dopamine and the positive expectation of the outcome of one’s own actions, and may have implications for the management of PD.

  6. Neural Correlates of Action Observation and Execution in 14-Month-Old Infants: An Event-Related EEG Desynchronization Study

    Science.gov (United States)

    Marshall, Peter J.; Young, Thomas; Meltzoff, Andrew N.

    2011-01-01

    There is increasing interest in neurobiological methods for investigating the shared representation of action perception and production in early development. We explored the extent and regional specificity of EEG desynchronization in the infant alpha frequency range (6-9 Hz) during action observation and execution in 14-month-old infants.…

  7. "Understanding the role of speech production in reading: Evidence for a print-to-speech neural network using graphical analysis": Correction to Cummine et al. (2016).

    Science.gov (United States)

    2017-05-01

    Reports an error in "Understanding the role of speech production in reading: Evidence for a print-to-speech neural network using graphical analysis" by Jacqueline Cummine, Ivor Cribben, Connie Luu, Esther Kim, Reyhaneh Bahktiari, George Georgiou and Carol A. Boliek (Neuropsychology, 2016[May], Vol 30[4], 385-397). In the article, the fifth author's name [Bakhtiari] was misspelled. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2015-49069-001.) Objective: The neural circuitry associated with language processing is complex and dynamic. Graphical models are useful for studying complex neural networks as this method provides information about unique connectivity between regions within the context of the entire network of interest. Here, the authors explored the neural networks during covert reading to determine the role of feedforward and feedback loops in covert speech production. Brain activity of skilled adult readers was assessed in real word and pseudoword reading tasks with functional MRI (fMRI). The authors provide evidence for activity coherence in the feedforward system (inferior frontal gyrus-supplementary motor area) during real word reading and in the feedback system (supramarginal gyrus-precentral gyrus) during pseudoword reading. Graphical models provided evidence of an extensive, highly connected, neural network when individuals read real words that relied on coordination of the feedforward system. In contrast, when individuals read pseudowords the authors found a limited/restricted network that relied on coordination of the feedback system. Together, these results underscore the importance of considering multiple pathways and articulatory loops during language tasks and provide evidence for a print-to-speech neural network. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. The modulating effect of personality traits on neural error monitoring: evidence from event-related FMRI.

    Directory of Open Access Journals (Sweden)

    Zrinka Sosic-Vasic

    Full Text Available The present study investigated the association between traits of the Five Factor Model of Personality (Neuroticism, Extraversion, Openness for Experiences, Agreeableness, and Conscientiousness and neural correlates of error monitoring obtained from a combined Eriksen-Flanker-Go/NoGo task during event-related functional magnetic resonance imaging in 27 healthy subjects. Individual expressions of personality traits were measured using the NEO-PI-R questionnaire. Conscientiousness correlated positively with error signaling in the left inferior frontal gyrus and adjacent anterior insula (IFG/aI. A second strong positive correlation was observed in the anterior cingulate gyrus (ACC. Neuroticism was negatively correlated with error signaling in the inferior frontal cortex possibly reflecting the negative inter-correlation between both scales observed on the behavioral level. Under present statistical thresholds no significant results were obtained for remaining scales. Aligning the personality trait of Conscientiousness with task accomplishment striving behavior the correlation in the left IFG/aI possibly reflects an inter-individually different involvement whenever task-set related memory representations are violated by the occurrence of errors. The strong correlations in the ACC may indicate that more conscientious subjects were stronger affected by these violations of a given task-set expressed by individually different, negatively valenced signals conveyed by the ACC upon occurrence of an error. Present results illustrate that for predicting individual responses to errors underlying personality traits should be taken into account and also lend external validity to the personality trait approach suggesting that personality constructs do reflect more than mere descriptive taxonomies.

  9. The modulating effect of personality traits on neural error monitoring: evidence from event-related FMRI.

    Science.gov (United States)

    Sosic-Vasic, Zrinka; Ulrich, Martin; Ruchsow, Martin; Vasic, Nenad; Grön, Georg

    2012-01-01

    The present study investigated the association between traits of the Five Factor Model of Personality (Neuroticism, Extraversion, Openness for Experiences, Agreeableness, and Conscientiousness) and neural correlates of error monitoring obtained from a combined Eriksen-Flanker-Go/NoGo task during event-related functional magnetic resonance imaging in 27 healthy subjects. Individual expressions of personality traits were measured using the NEO-PI-R questionnaire. Conscientiousness correlated positively with error signaling in the left inferior frontal gyrus and adjacent anterior insula (IFG/aI). A second strong positive correlation was observed in the anterior cingulate gyrus (ACC). Neuroticism was negatively correlated with error signaling in the inferior frontal cortex possibly reflecting the negative inter-correlation between both scales observed on the behavioral level. Under present statistical thresholds no significant results were obtained for remaining scales. Aligning the personality trait of Conscientiousness with task accomplishment striving behavior the correlation in the left IFG/aI possibly reflects an inter-individually different involvement whenever task-set related memory representations are violated by the occurrence of errors. The strong correlations in the ACC may indicate that more conscientious subjects were stronger affected by these violations of a given task-set expressed by individually different, negatively valenced signals conveyed by the ACC upon occurrence of an error. Present results illustrate that for predicting individual responses to errors underlying personality traits should be taken into account and also lend external validity to the personality trait approach suggesting that personality constructs do reflect more than mere descriptive taxonomies.

  10. Neural bases of falsification in conditional proposition testing: evidence from an fMRI study.

    Science.gov (United States)

    Liu, Jimei; Zhang, Meng; Jou, Jerwen; Wu, Xin; Li, Wei; Qiu, Jiang

    2012-08-01

    The ability of testing the validity of a conditional statement is important in our everyday life. However, the brain mechanisms underlying this process, especially falsification process which is important in daily life, but especially crucial to scientific reasoning and research is not as yet completely clear. Therefore, in the present study, we used event-related functional magnetic resonance imaging (fMRI) to examine the neural bases of the falsification process in testing the validity of a conditional statement as used in Wason's (1966) selection task. Our fMRI results showed that: (1) compared with the baseline condition, both Falsification (by using Modus Ponens, and Modus Tollens) and Non-Falsification conditions (affirming the consequent, and denying the antecedent) activated the left frontal areas (BA44/45, or BA6), and basal ganglia, the areas previously found in the rule-guided conditional reasoning operations; the parietal area (BA40, BA7) for recruiting cognitive resources to represent and maintain the different evidential information in working memory. (2) The left middle frontal gyrus (BA9) and cerebellum were shown to be activated in the contrast of Falsification condition versus Non-Falsification condition and in the contrast of MT versus Non-Falsification condition. These results indicated that the left middle frontal gyrus (BA9) might be the key brain region involved in the falsification process of conditional statement for which abstracting and integrating logical relationships, and inhibiting the distraction of the irrelevant information were the essential processes. Moreover, the cerebellum was found to be responsible for constructing an internal working model. In addition, our brain imaging results might support the dual-process theory of reasoning.

  11. Neural evidence for distracter suppression during visual search in real-world scenes.

    Science.gov (United States)

    Seidl, Katharina N; Peelen, Marius V; Kastner, Sabine

    2012-08-22

    Selecting visual information from cluttered real-world scenes involves the matching of visual input to the observer's attentional set--an internal representation of objects that are relevant for current behavioral goals. When goals change, a new attentional set needs to be instantiated, requiring the suppression of the previous set to prevent distraction by objects that are no longer relevant. In the present fMRI study, we investigated how such suppression is implemented at the neural level. We measured human brain activity in response to natural scene photographs that could contain objects from (1) a currently relevant (target) category, (2) a previously but not presently relevant (distracter) category, and/or (3) a never relevant (neutral) category. Across conditions, multivoxel response patterns in object-selective cortex carried information about objects present in the scenes. However, this information strongly depended on the task relevance of the objects. As expected, information about the target category was significantly increased relative to the neutral category, indicating top-down enhancement of task-relevant information. Importantly, information about the distracter category was significantly reduced relative to the neutral category, indicating that the processing of previously relevant objects was suppressed. Such active suppression at the level of high-order visual cortex may serve to prevent the erroneous selection of, or interference from, objects that are no longer relevant to ongoing behavior. We conclude that the enhancement of relevant information and the suppression of distracting information both contribute to the efficient selection of visual information from cluttered real-world scenes.

  12. Health inequity in people with intellectual disabilities: from evidence to action applying an appreciative inquiry approach

    NARCIS (Netherlands)

    Naaldenberg, J.; Banks, R.; Lennox, N.; Ouellette-Kunz, H.; Meijer, M.; Schrojenstein Lantman, H.M. van

    2015-01-01

    BACKGROUND: The current understanding of health inequities in people with intellectual disabilities does not readily translate into improvements in health status or health care. To identify opportunities for action, the 2013 IASSIDD health SIRG conference organized ten intensive workshops. MATERIALS

  13. Interactive actions of Bdnf methylation and cell metabolism for building neural resilience under the influence of diet

    OpenAIRE

    Tyagi, Ethika; Zhuang, Yumei; Agrawal, Rahul; Ying, Zhe; Gomez-Pinilla, Fernando

    2014-01-01

    Quality nutrition during the period of brain formation is a predictor of brain functional capacity and plasticity during adulthood; however it is not clear how this conferred plasticity imparts long-term neural resilience. Here we report that early exposure to dietary omega-3 fatty acids orchestrates key interactions between metabolic signals and Bdnf methylation creating a reservoir of neuroplasticity that can protect the brain against the deleterious effects of switching to a western diet (...

  14. Prevention and control of noncommunicable diseases through evidence-based public health: implementing the NCD 2020 action plan.

    Science.gov (United States)

    Diem, Günter; Brownson, Ross C; Grabauskas, Vilius; Shatchkute, Aushra; Stachenko, Sylvie

    2016-09-01

    The control of noncommunicable diseases (NCDs) was addressed by the declaration of the 66th United Nations (UN) General Assembly followed by the World Health Organization's (WHO) NCD 2020 action plan. There is a clear need to better apply evidence in public health settings to tackle both behaviour-related factors and the underlying social and economic conditions. This article describes concepts of evidence-based public health (EBPH) and outlines a set of actions that are essential for successful global NCD prevention. The authors describe the importance of knowledge translation with the goal of increasing the effectiveness of public health services, relying on both quantitative and qualitative evidence. In particular, the role of capacity building is highlighted because it is fundamental to progress in controlling NCDs. Important challenges for capacity building include the need to bridge diverse disciplines, build the evidence base across countries and the lack of formal training in public health sciences. As brief case examples, several successful capacity-building efforts are highlighted to address challenges and further evidence-based decision making. The need for a more comprehensive public health approach, addressing social, environmental and cultural conditions, has led to government-wide and society-wide strategies that are now on the agenda due to efforts such as the WHO's NCD 2020 action plan and Health 2020: the European Policy for Health and Wellbeing. These efforts need research to generate evidence in new areas (e.g. equity and sustainability), training to build public health capacity and a continuous process of improvement and knowledge generation and translation.

  15. Neural and muscular control functions of the gut in odontocetes: morphologic evidence in beaked whales and beluga whales.

    Science.gov (United States)

    Pfeiffer, C J

    1993-01-01

    The present data provide some new and unique, gastrointestinal morphologic findings in two species of toothed whales, the Cuvier's beaked whale (Ziphius cavirostris) and the beluga or white whale (Delphinapterus leucas), which are discussed relative to their atypical feeding behavior and alimentary tract functions. Specifically, the findings show myenteric neural modifications and muscularis externa structural specializations which may support voluntary and involuntary fore- and hindgut behavior. Histologic evidence of intercalation-like striations in the gastric and colonic musculature was discovered, as well as an unusual massive size of the colonic myenteric plexuses. These observations, which are not evident in terrestrial mammalian gastrointestinal tracts, may help explain the unusual upper gastrointestinal tract motility such as ingestion-by-sucking in the absence of prehensile teeth and processing of ingesta in a multi-compartmentalized pyloric stomach. Further, the hindgut modifications may help explain the animal's acute, rectal discharge escape mechanism, likened to squid inking, which seems to be an evolved function of some cetaceans.

  16. Three speech sounds, one motor action: Evidence for speech-motor disparity from English flap production

    OpenAIRE

    Derrick, Donald; Stavness, Ian; Gick, Bryan

    2015-01-01

    The assumption that units of speech production bear a one-to-one relationship to speech motor actions pervades otherwise widely varying theories of speech motor behavior. This speech production and simulation study demonstrates that commonly occurring flap sequences may violate this assumption. In the word “Saturday,” a sequence of three sounds may be produced using a single, cyclic motor action. Under this view, the initial upward tongue tip motion, starting with the first vowel and moving t...

  17. Dissociation between Semantic Representations for Motion and Action Verbs: Evidence from Patients with Left Hemisphere Lesions

    Science.gov (United States)

    Taylor, Lawrence J.; Evans, Carys; Greer, Joanna; Senior, Carl; Coventry, Kenny R.; Ietswaart, Magdalena

    2017-01-01

    This multiple single case study contrasted left hemisphere stroke patients (N = 6) to healthy age-matched control participants (N = 15) on their understanding of action (e.g., holding, clenching) and motion verbs (e.g., crumbling, flowing). The tasks required participants to correctly identify the matching verb or associated picture. Dissociations on action and motion verb content depending on lesion site were expected. As predicted for verbs containing an action and/or motion content, modified t-tests confirmed selective deficits in processing motion verbs in patients with lesions involving posterior parietal and lateral occipitotemporal cortex. In contrast, deficits in verbs describing motionless actions were found in patients with more anterior lesions sparing posterior parietal and lateral occipitotemporal cortex. These findings support the hypotheses that semantic representations for action and motion are behaviorally and neuro-anatomically dissociable. The findings clarify the differential and critical role of perceptual and motor regions in processing modality-specific semantic knowledge as opposed to a supportive but not necessary role. We contextualize these results within theories from both cognitive psychology and cognitive neuroscience that make claims over the role of sensory and motor information in semantic representation. PMID:28261070

  18. Dissociation between Semantic Representations for Motion and Action Verbs: Evidence from Patients with Left Hemisphere Lesions.

    Science.gov (United States)

    Taylor, Lawrence J; Evans, Carys; Greer, Joanna; Senior, Carl; Coventry, Kenny R; Ietswaart, Magdalena

    2017-01-01

    This multiple single case study contrasted left hemisphere stroke patients (N = 6) to healthy age-matched control participants (N = 15) on their understanding of action (e.g., holding, clenching) and motion verbs (e.g., crumbling, flowing). The tasks required participants to correctly identify the matching verb or associated picture. Dissociations on action and motion verb content depending on lesion site were expected. As predicted for verbs containing an action and/or motion content, modified t-tests confirmed selective deficits in processing motion verbs in patients with lesions involving posterior parietal and lateral occipitotemporal cortex. In contrast, deficits in verbs describing motionless actions were found in patients with more anterior lesions sparing posterior parietal and lateral occipitotemporal cortex. These findings support the hypotheses that semantic representations for action and motion are behaviorally and neuro-anatomically dissociable. The findings clarify the differential and critical role of perceptual and motor regions in processing modality-specific semantic knowledge as opposed to a supportive but not necessary role. We contextualize these results within theories from both cognitive psychology and cognitive neuroscience that make claims over the role of sensory and motor information in semantic representation.

  19. Nucleus accumbens is involved in human action monitoring: evidence from invasive electrophysiological recordings

    Directory of Open Access Journals (Sweden)

    Thomas F Münte

    2008-03-01

    Full Text Available The Nucleus accumbens (Nacc has been proposed to act as a limbic-motor interface. Here, using invasive intraoperative recordings in an awake patient suffering from obsessive-compulsive disease (OCD, we demonstrate that its activity is modulated by the quality of performance of the subject in a choice reaction time task designed to tap action monitoring processes. Action monitoring, that is, error detection and correction, is thought to be supported by a system involving the dopaminergic midbrain, the basal ganglia, and the medial prefrontal cortex. In surface electrophysiological recordings, action monitoring is indexed by an error-related negativity (ERN appearing time-locked to the erroneous responses and emanating from the medial frontal cortex. In preoperative scalp recordings the patient's ERN was found to be signifi cantly increased compared to a large (n= 83 normal sample, suggesting enhanced action monitoring processes. Intraoperatively, error-related modulations were obtained from the Nacc but not from a site 5 mm above. Importantly, crosscorrelation analysis showed that error-related activity in the Nacc preceded surface activity by 40 ms. We propose that the Nacc is involved in action monitoring, possibly by using error signals from the dopaminergic midbrain to adjust the relative impact of limbic and prefrontal inputs on frontal control systems in order to optimize goal-directed behavior.

  20. Evidence of involvement of central neural mechanisms in generating fibromyalgia pain.

    Science.gov (United States)

    Staud, Roland

    2002-08-01

    Fibromyalgia syndrome (FMS) is characterized by widespread pain, fatigue, sleep abnormalities, and distress. Because FMS lacks consistent evidence of tissue abnormalities, recent investigations have focused on central nervous system mechanisms of pain. Abnormal temporal summation of second pain (wind-up) and central sensitization have been described recently in patients with FMS. Wind-up and central sensitization, which rely on central pain mechanisms, occur after prolonged C-nociceptor input and depend on activation of nociceptor-specific neurons and wide dynamic range neurons in the dorsal horn of the spinal cord. Other abnormal central pain mechanisms recently detected in patients with FMS include diffuse noxious inhibitory controls. These pain inhibitory mechanisms rely on spinal cord and supraspinal systems involving pain facilitatory and pain inhibitory pathways. Brain-imaging techniques that can detect neuronal activation after nociceptive stimuli have provided additional evidence for abnormal central pain mechanisms in FMS. Brain images have corroborated the augmented reported pain experience of patients with fibromyalgia during experimental pain stimuli. In addition, thalamic activity, which contributes significantly to pain processing, was decreased in fibromyalgia. However, central pain mechanisms of fibromyalgia may not depend exclusively on neuronal activation. Neuroglial activation has been found to play an important role in the induction and maintenance of chronic pain. These findings may have important implications for future research and the treatment of fibromyalgia pain.

  1. Anticipatory affect during action preparation: evidence from backward compatibility in dual-task performance.

    Science.gov (United States)

    Eder, Andreas B; Pfister, Roland; Dignath, David; Hommel, Bernhard

    2016-07-14

    Upcoming responses in the second of two subsequently performed tasks can speed up compatible responses in the temporally preceding first task. Two experiments extend previous demonstration of such backward compatibility to affective features: responses to affective stimuli were faster in Task 1 when an affectively compatible response effect was anticipated for Task 2. This emotional backward-compatibility effect demonstrates that representations of the affective consequences of the Task 2 response were activated before the selection of a response in Task 1 was completed. This finding is problematic for the assumption of a serial stimulus-response translation stage. It also shows that the affective consequence of a response is anticipated during, and has an impact on stimulus-response translation, which implies that action planning considers codes representing and predicting the emotional consequences of actions. Implications for the control of emotional actions are discussed.

  2. "Comments on Slavin": Synthesizing Evidence from Impact Evaluations in Education to Inform Action

    Science.gov (United States)

    Chatterji, Madhabi

    2008-01-01

    Traditional methods for preparing systematic reviews and syntheses of effectiveness studies rely on a limited set of methodological criteria to include studies that measure and report effects too narrowly to forward the mission of evidence-based practice. This article discusses why and how the criteria for study selection, evidence screening, and…

  3. Object manipulation and motion perception: Evidence of an influence of action planning on visual processing

    NARCIS (Netherlands)

    Lindemann, O.; Bekkering, H.

    2009-01-01

    In 3 experiments, the authors investigated the bidirectional coupling of perception and action in the context of object manipulations and motion perception. Participants prepared to grasp an X-shaped object along one of its 2 diagonals and to rotate it in a clockwise or a counterclockwise direction.

  4. Do Affirmative Action Bans Lower Minority College Enrollment and Attainment?: Evidence from Statewide Bans

    Science.gov (United States)

    Backes, Ben

    2012-01-01

    Using institutional data on race-specific college enrollment and completion, I examine whether minority students were less likely to enroll in a four-year public college or receive a degree following a statewide affirmative action ban. As in previous studies, I find that black and Hispanic enrollment dropped at the top institutions; however, there…

  5. The Theory of Reasoned Action and Self-Construal: Evidence from Three Cultures.

    Science.gov (United States)

    Park, Hee Sun; Levine, Timothy R.

    1999-01-01

    Investigates the effects of self-construals on the attitudinal and normative components of the Theory of Reasoned Action in the cultures of Korea, Hawaii, and the mainland United States. Finds that undergraduate students in all three locations scored higher on independence than interdependence, and culture appears to affect the extent to which…

  6. UN Global Action Programme and Education for Sustainable Development: A Critical Appraisal of the Evidence Base

    Science.gov (United States)

    Fischer, Daniel; Aubrecht, Elisabeth Lena; Brück, Maria; Ditges, Laura; Gathen, Lea; Jahns, Maximilian; Petersmann, Moritz; Rau, Jörn; Wellmann, Christiane

    2015-01-01

    The United Nations (UN) proclaimed the years 2005 to 2014 the World Decade on Education for Sustainable Development (ESD). As a follow up on the World Decade, the UN launched a Global Action Programme (GAP) that is designed to set the framework for international activities on ESD. The GAP focuses on five priority areas that are of high relevance…

  7. Simulating the 'other-race' effect with autoassociative neural networks: further evidence in favor of the face-space model.

    Science.gov (United States)

    Caldara, Roberto; Hervé, Abdi

    2006-01-01

    Other-race (OR) faces are less accurately recognized than same-race (SR) faces, but faster classified by race. This phenomenon has often been reported as the 'other-race' effect (ORE). Valentine (1991 Quarterly Journal of Experimental Psychology A: Human Experimental Psychology 43 161-204) proposed a theoretical multidimensional face-space model that explained both of these results, in terms of variations in exemplar density between races. According to this model, SR faces are more widely distributed across the dimensions of the space than OR faces. However, this model does not quantify nor state the dimensions coded within this face space. The aim of the present study was to test the face-space explanation of the ORE with neural network simulations by quantifying its dimensions. We found the predicted density properties of Valentine's framework in the face-projection spaces of the autoassociative memories. This was supported by an interaction for exemplar density between the race of the learned face set and the race of the faces. In addition, the elaborated face representations showed optimal responses for SR but not for OR faces within SR face spaces when explored at the individual level, as gender errors occurred significantly more often in OR than in SR face-space representations. Altogether, our results add further evidence in favor of a statistical exemplar density explanation of the ORE as suggested by Valentine, and question the plausibility of such coding for faces in the framework of recent neuroimaging studies.

  8. The Physics of Decision Making:. Stochastic Differential Equations as Models for Neural Dynamics and Evidence Accumulation in Cortical Circuits

    Science.gov (United States)

    Holmes, Philip; Eckhoff, Philip; Wong-Lin, K. F.; Bogacz, Rafal; Zacksenhouse, Miriam; Cohen, Jonathan D.

    2010-03-01

    We describe how drift-diffusion (DD) processes - systems familiar in physics - can be used to model evidence accumulation and decision-making in two-alternative, forced choice tasks. We sketch the derivation of these stochastic differential equations from biophysically-detailed models of spiking neurons. DD processes are also continuum limits of the sequential probability ratio test and are therefore optimal in the sense that they deliver decisions of specified accuracy in the shortest possible time. This leaves open the critical balance of accuracy and speed. Using the DD model, we derive a speed-accuracy tradeoff that optimizes reward rate for a simple perceptual decision task, compare human performance with this benchmark, and discuss possible reasons for prevalent sub-optimality, focussing on the question of uncertain estimates of key parameters. We present an alternative theory of robust decisions that allows for uncertainty, and show that its predictions provide better fits to experimental data than a more prevalent account that emphasises a commitment to accuracy. The article illustrates how mathematical models can illuminate the neural basis of cognitive processes.

  9. Discovering the dementia evidence base: Tools to support knowledge to action in dementia care (innovative practice).

    Science.gov (United States)

    Hayman, Sarah L; Tieman, Jennifer J

    2016-09-01

    Dementia requires expert care and decision making, based on sound evidence. Reliable evidence is difficult for busy dementia care professionals to find quickly. This study developed an experimentally tested search filter as an innovative tool to retrieve literature on dementia. It has a known retrieval performance and can be provided as an open access web link directly to current literature. The Dementia Search Filter was developed using validated methodology. An Expert Advisory Group of dementia care practitioners and researchers ratified a representative set of relevant studies and undertook post hoc relevance assessment, to ensure the usefulness of the search filter. The Dementia Search Filter is published on two websites and combined with expert searches to link to evidence on dementia, at end of life in aged care settings and more generally. Evidence accessed by the Dementia Search Filter will help overcome barriers to finding current relevant research in the field, for practitioners, researchers and decision makers.

  10. Neural evidence for competition-mediated suppression in the perception of a single object.

    Science.gov (United States)

    Cacciamani, Laura; Scalf, Paige E; Peterson, Mary A

    2015-11-01

    Multiple objects compete for representation in visual cortex. Competition may also underlie the perception of a single object. Computational models implement object perception as competition between units on opposite sides of a border. The border is assigned to the winning side, which is perceived as an object (or "figure"), whereas the other side is perceived as a shapeless ground. Behavioral experiments suggest that the ground is inhibited to a degree that depends on the extent to which it competed for object status, and that this inhibition is relayed to low-level brain areas. Here, we used fMRI to assess activation for ground regions of task-irrelevant novel silhouettes presented in the left or right visual field (LVF or RVF) while participants performed a difficult task at fixation. Silhouettes were designed so that the insides would win the competition for object status. The outsides (grounds) suggested portions of familiar objects in half of the silhouettes and novel objects in the other half. Because matches to object memories affect the competition, these two types of silhouettes operationalized, respectively, high competition and low competition from the grounds. The results showed that activation corresponding to ground regions was reduced for high- versus low-competition silhouettes in V4, where receptive fields (RFs) are large enough to encompass the familiar objects in the grounds, and in V1/V2, where RFs are much smaller. These results support a theory of object perception involving competition-mediated ground suppression and feedback from higher to lower levels. This pattern of results was observed in the left hemisphere (RVF), but not in the right hemisphere (LVF). One explanation of the lateralized findings is that task-irrelevant silhouettes in the RVF captured attention, allowing us to observe these effects, whereas those in the LVF did not. Experiment 2 provided preliminary behavioral evidence consistent with this possibility.

  11. Working memory encoding and maintenance deficits in schizophrenia: neural evidence for activation and deactivation abnormalities.

    Science.gov (United States)

    Anticevic, Alan; Repovs, Grega; Barch, Deanna M

    2013-01-01

    Substantial evidence implicates working memory (WM) as a core deficit in schizophrenia (SCZ), purportedly due to primary deficits in dorsolateral prefrontal cortex functioning. Recent findings suggest that SCZ is also associated with abnormalities in suppression of certain regions during cognitive engagement--namely the default mode system--that may further contribute to WM pathology. However, no study has systematically examined activation and suppression abnormalities across both encoding and maintenance phases of WM in SCZ. Twenty-eight patients and 24 demographically matched healthy subjects underwent functional magnetic resonance imaging at 3T while performing a delayed match-to-sample WM task. Groups were accuracy matched to rule out performance effects. Encoding load was identical across subjects to facilitate comparisons across WM phases. We examined activation differences using an assumed model approach at the whole-brain level and within meta-analytically defined WM areas. Despite matched performance, we found regions showing less recruitment during encoding and maintenance for SCZ subjects. Furthermore, we identified 2 areas closely matching the default system, which SCZ subjects failed to deactivate across WM phases. Lastly, activation in prefrontal regions predicted the degree of deactivation for healthy but not SCZ subjects. Current results replicate and extend prefrontal recruitment abnormalities across WM phases in SCZ. Results also indicate deactivation abnormalities across WM phases, possibly due to inefficient prefrontal recruitment. Such regional deactivation may be critical for suppressing sources of interference during WM trace formation. Thus, deactivation deficits may constitute an additional source of impairments, which needs to be further characterized for a complete understanding of WM pathology in SCZ.

  12. Neural networks for action representation underlying automatic mimicry: A functional magnetic-resonance imaging and dynamic causal modeling study

    Directory of Open Access Journals (Sweden)

    Akihiro T Sasaki

    2012-08-01

    Full Text Available Automatic mimicry is based on the tight linkage between motor and perception action representations in which internal models play a key role. Based on the anatomical connection, we hypothesized that the direct effective connectivity from the posterior superior temporal sulcus (pSTS to the ventral premotor area (PMv formed an inverse internal model, converting visual representation into a motor plan, and that reverse connectivity formed a forward internal model, converting the motor plan into a sensory outcome of action. To test this hypothesis, we employed dynamic causal-modeling analysis with functional magnetic-resonance imaging. Twenty-four normal participants underwent a change-detection task involving two visually-presented balls that were either manually rotated by the investigator’s right hand (‘Hand’ or automatically rotated. The effective connectivity from the pSTS to the PMv was enhanced by hand observation and suppressed by execution, corresponding to the inverse model. Opposite effects were observed from the PMv to the pSTS, suggesting the forward model. Additionally, both execution and hand observation commonly enhanced the effective connectivity from the pSTS to the inferior parietal lobule (IPL, the IPL to the primary sensorimotor cortex (S/M1, the PMv to the IPL, and the PMv to the S/M1. Representation of the hand action therefore was implemented in the motor system including the S/M1. During hand observation, effective connectivity toward the pSTS was suppressed whereas that toward the PMv and S/M1 was enhanced. Thus the action-representation network acted as a dynamic feedback-control system during action observation.

  13. Neural circuitry underlying the central hypertensive action of nesfatin-1: melanocortins, corticotropin-releasing hormone, and oxytocin.

    Science.gov (United States)

    Yosten, Gina L C; Samson, Willis K

    2014-05-15

    Nesfatin-1 is produced in the periphery and in the brain where it has been demonstrated to regulate appetite, stress hormone secretion, and cardiovascular function. The anorexigenic action of central nesfatin-1 requires recruitment of neurons producing the melanocortins and centrally projecting oxytocin (OT) and corticotropin-releasing hormone (CRH) neurons. We previously have shown that two components of this pathway, the central melanocortin and oxytocin systems, contribute to the hypertensive action of nesfatin-1 as well. We hypothesized that the cardiovascular effect of nesfatin-1 also was dependent on activation of neurons expressing CRH receptors, and that the order of activation of the melanocortin-CRH-oxytocin circuit was preserved for both the anorexigenic and hypertensive actions of the peptide. Pretreatment of male rats with the CRH-2 receptor antagonist astressin2B abrogated nesfatin-1-induced increases in mean arterial pressure (MAP). Furthermore, the hypertensive action of CRH was blocked by pretreatment with an oxytocin receptor antagonist ornithine vasotocin (OVT), indicating that the hypertensive effect of nesfatin-1 may require activation of oxytocinergic (OTergic) neurons in addition to recruitment of CRH neurons. Interestingly, we found that the hypertensive effect of α-melanocyte stimulating hormone (α-MSH) itself was not blocked by either astressin2B or OVT. These data suggest that while α-MSH-producing neurons are part of a core melanocortin-CRH-oxytocin circuit regulating food intake, and a subpopulation of melanocortin neurons activated by nesfatin-1 do mediate the hypertensive action of the peptide, α-MSH can signal independently from this circuit to increase MAP.

  14. Economic evidence on identifying clinically actionable findings with whole-genome sequencing: a scoping review.

    OpenAIRE

    2016-01-01

    The American College of Medical Genetics and Genomics (ACMG) recommends that mutations in 56 genes for 24 conditions are clinically actionable and should be reported as secondary findings after whole-genome sequencing (WGS). Our aim was to identify published economic evaluations of detecting mutations in these genes among the general population or among targeted/high-risk populations and conditions and identify gaps in knowledge. A targeted PubMed search from 1994 through November 2014 was pe...

  15. Can Authorization Reduce Poverty among Undocumented Immigrants? Evidence from the Deferred Action for Childhood Arrivals Program

    OpenAIRE

    Amuedo-Dorantes, Catalina; Antman, Francisca M.

    2016-01-01

    We explore the impact of authorization on the poverty exposure of households headed by undocumented immigrants. The identification strategy makes use of the 2012 Deferred Action for Childhood Arrivals (DACA) program, which provided a temporary work authorization and reprieve from deportation to eligible immigrants. Using a difference-in-differences approach, we compare DACA-eligible to DACA-ineligible likely unauthorized immigrants, before and after the program implementation. We find that DA...

  16. The real-time link between person perception and action: brain potential evidence for dynamic continuity.

    Science.gov (United States)

    Freeman, Jonathan B; Ambady, Nalini; Midgley, Katherine J; Holcomb, Phillip J

    2011-01-01

    Using event-related potentials, we investigated how the brain extracts information from another's face and translates it into relevant action in real time. In Study 1, participants made between-hand sex categorizations of sex-typical and sex-atypical faces. Sex-atypical faces evoked negativity between 250 and 550 ms (N300/N400 effects), reflecting the integration of accumulating sex-category knowledge into a coherent sex-category interpretation. Additionally, the lateralized readiness potential revealed that the motor cortex began preparing for a correct hand response while social category knowledge was still gradually evolving in parallel. In Study 2, participants made between-hand eye-color categorizations as part of go/no-go trials that were contingent on a target's sex. On no-go trials, although the hand did not actually move, information about eye color partially prepared the motor cortex to move the hand before perception of sex had finalized. Together, these findings demonstrate the dynamic continuity between person perception and action, such that ongoing results from face processing are immediately and continuously cascaded into the motor system over time. The preparation of action begins based on tentative perceptions of another's face before perceivers have finished interpreting what they just saw.

  17. Action observation treatment improves recovery of postsurgical orthopedic patients: evidence for a top-down effect?

    Science.gov (United States)

    Bellelli, Giuseppe; Buccino, Giovanni; Bernardini, Bruno; Padovani, Alessandro; Trabucchi, Marco

    2010-10-01

    To assess whether action observation treatment (AOT) may also improve motor recovery in postsurgical orthopedic patients, in addition to conventional physiotherapy. Randomized controlled trial. Department of rehabilitation. Patients (N=60) admitted to our department postorthopedic surgery were randomly assigned to either a case (n=30) or control (n=30) group. Exclusion criteria were age 18 years or younger and 90 years or older, Mini-Mental State Examination score of 21 of 30 or lower, no ambulating order, advanced vision impairment, malignancy, pneumonia, or heart failure. All participants underwent conventional physiotherapy. In addition, patients in the case group were asked to observe video clips showing daily actions and to imitate them afterward. Patients in the control group were asked to observe video clips with no motor content and to execute the same actions as patients in the case group afterward. Participants were scored on functional scales at baseline and after treatment by a physician blinded to group assignment. Changes in FIM and Tinetti scale scores, and dependence on walking aids. At baseline, groups did not differ in clinical and functional scale scores. After treatment, patients in the case group scored better than patients in the control group (FIM total score, P=.02; FIM motor subscore, P=.001; Tinetti scale score, P=.04); patients in the case group were assigned more frequently to 1 crutch (P=.01). In addition to conventional physiotherapy, AOT is effective in the rehabilitation of postsurgical orthopedic patients. The present results strongly support top-down effects of this treatment in motor recovery, even in nonneurologic patients. Copyright © 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Computational Framework Explains How Animals Select Actions With Rewarding Outcomes

    OpenAIRE

    Gurney, K.N.; Humphries, M.D.; Redgrave, P.

    2015-01-01

    Operant learning requires that reinforcement signals interact with action representations at a suitable neural interface. Much evidence suggests that this occurs when phasic dopamine, acting as a reinforcement prediction error, gates plasticity at cortico-striatal synapses, and thereby changes the future likelihood of selecting the action(s) coded by striatal neurons. But this hypothesis faces serious challenges. First, cortico-striatal plasticity is inexplicably complex, depending on spike t...

  19. Preliminary evidence for a postsynaptic action of beta-bungarotoxin in mammalian skeletal muscle

    Science.gov (United States)

    Storella, R. J.; Schouchoff, A. L.; Fujii, M.; Hill, J.; Fletcher, J. E.; Jiang, M. S.; Smith, L. A.

    1992-01-01

    Two hours after treatment with beta-bungarotoxin (0.34-0.4 microM), when there was complete neuromuscular block, the peak contracture response to 50 microM succinylcholine was significantly reduced by about 35% in the mouse phrenic nerve-diaphragm preparation. Additionally, significant phospholipase A2 activity was detected on primary cell cultures from skeletal muscle which were incubated for 2 hr with concentrations of beta-bungarotoxin greater than or equal to 0.1 microM. Thus, beta-bungarotoxin appears to have pharmacologically and biochemically detectable postsynaptic actions in mammalian muscle systems.

  20. Preliminary evidence for a postsynaptic action of beta-bungarotoxin in mammalian skeletal muscle

    Science.gov (United States)

    Storella, R. J.; Schouchoff, A. L.; Fujii, M.; Hill, J.; Fletcher, J. E.; Jiang, M. S.; Smith, L. A.

    1992-01-01

    Two hours after treatment with beta-bungarotoxin (0.34-0.4 microM), when there was complete neuromuscular block, the peak contracture response to 50 microM succinylcholine was significantly reduced by about 35% in the mouse phrenic nerve-diaphragm preparation. Additionally, significant phospholipase A2 activity was detected on primary cell cultures from skeletal muscle which were incubated for 2 hr with concentrations of beta-bungarotoxin greater than or equal to 0.1 microM. Thus, beta-bungarotoxin appears to have pharmacologically and biochemically detectable postsynaptic actions in mammalian muscle systems.

  1. Enforcement actions and their effectiveness in securities regulation:Empirical evidence from management earnings forecasts

    Institute of Scientific and Technical Information of China (English)

    Yunling Song; Xinwei Ji

    2012-01-01

    Due to resource constraints,securities regulators cannot find or punish all firms that have conducted irregular or even illegal activities(hereafter referred to as fraud).Those who study securities regulations can only find the instances of fraud that have been punished,not those that have not been punished,and it is these unknown cases that would make the best control sample for studies of enforcement action criteria.China’s mandatory management earnings forecasts solve this sampling problem.In the A-share market,firms that have not forecasted as mandated are likely in a position to be punished by securities regulators or are attempting to escape punishment,and their identification allows researchers to build suitable study and control samples when examining securities regulations.Our results indicate that enforcement actions taken by securities regulators are selective.The probability that a firm will be punished for irregular management forecasting is significantly related to proxies for survival rates.Specifically,fraudulent firms with lower return on assets(ROAs) or higher cash flow risk are more likely to be punished.Further analysis shows that selective enforcement of regulations has had little positive effect on the quality of listed firms’ management forecasts.

  2. What is the role of motor simulation in action and object recognition? Evidence from apraxia.

    Science.gov (United States)

    Negri, Gioia A L; Rumiati, Raffaella I; Zadini, Antonietta; Ukmar, Maja; Mahon, Bradford Z; Caramazza, Alfonso

    2007-12-01

    An important issue in contemporary cognitive neuroscience concerns the role of motor production processes in perceptual and conceptual analysis. To address this issue, we studied the performance of a large group of unilateral stroke patients across a range of tasks using the same set of common manipulable objects. All patients (n = 37) were tested for their ability to demonstrate the use of the objects, recognize the objects, recognize the corresponding object-associated pantomimes, and imitate those same pantomimes. At the group level we observed reliable correlations between object use and pantomime recognition, object use and object recognition, and pantomime imitation and pantomime recognition. At the single-case level, we document that the ability to recognize actions and objects dissociates from the ability to use those same objects. These data are problematic for the hypothesis that motor processes are constitutively involved in the recognition of actions and objects and frame new questions about the inferences that are merited by recent findings in cognitive neuroscience.

  3. Enforcement actions and their effectiveness in securities regulation: Empirical evidence from management earnings forecasts

    Directory of Open Access Journals (Sweden)

    Yunling Song

    2012-03-01

    Full Text Available Due to resource constraints, securities regulators cannot find or punish all firms that have conducted irregular or even illegal activities (hereafter referred to as fraud. Those who study securities regulations can only find the instances of fraud that have been punished, not those that have not been punished, and it is these unknown cases that would make the best control sample for studies of enforcement action criteria. China’s mandatory management earnings forecasts solve this sampling problem. In the A-share market, firms that have not forecasted as mandated are likely in a position to be punished by securities regulators or are attempting to escape punishment, and their identification allows researchers to build suitable study and control samples when examining securities regulations. Our results indicate that enforcement actions taken by securities regulators are selective. The probability that a firm will be punished for irregular management forecasting is significantly related to proxies for survival rates. Specifically, fraudulent firms with lower return on assets (ROAs or higher cash flow risk are more likely to be punished. Further analysis shows that selective enforcement of regulations has had little positive effect on the quality of listed firms’ management forecasts.

  4. 10-Month-Old Infants Are Sensitive to the Time Course of Perceived Actions: Eye-Tracking and EEG Evidence

    Science.gov (United States)

    Bache, Cathleen; Springer, Anne; Noack, Hannes; Stadler, Waltraud; Kopp, Franziska; Lindenberger, Ulman; Werkle-Bergner, Markus

    2017-01-01

    Research has shown that infants are able to track a moving target efficiently – even if it is transiently occluded from sight. This basic ability allows prediction of when and where events happen in everyday life. Yet, it is unclear whether, and how, infants internally represent the time course of ongoing movements to derive predictions. In this study, 10-month-old crawlers observed the video of a same-aged crawling baby that was transiently occluded and reappeared in either a temporally continuous or non-continuous manner (i.e., delayed by 500 ms vs. forwarded by 500 ms relative to the real-time movement). Eye movement and rhythmic neural brain activity (EEG) were measured simultaneously. Eye movement analyses showed that infants were sensitive to slight temporal shifts in movement continuation after occlusion. Furthermore, brain activity associated with sensorimotor processing differed between observation of continuous and non-continuous movements. Early sensitivity to an action’s timing may hence be explained within the internal real-time simulation account of action observation. Overall, the results support the hypothesis that 10-month-old infants are well prepared for internal representation of the time course of observed movements that are within the infants’ current motor repertoire. PMID:28769831

  5. Self-other disturbance in borderline personality disorder: Neural, self-report, and performance-based evidence.

    Science.gov (United States)

    Beeney, Joseph E; Hallquist, Michael N; Ellison, William D; Levy, Kenneth N

    2016-01-01

    Individuals with borderline personality disorder (BPD) display an impoverished sense of self and representations of self and others that shift between positive and negative poles. However, little research has investigated the nature of representational disturbance in BPD. The present study takes a multimodal approach. A card sort task was used to investigate complexity, integration, and valence of self-representation in BPD. Impairment in maintenance of self and other representations was assessed using a personality representational maintenance task. Finally, functional MRI (fMRI) was used to assess whether individuals with BPD show neural abnormalities related specifically to the self and what brain areas may be related to poor representational maintenance. Individuals with BPD sorted self-aspects suggesting more complexity of self-representation, but also less integration and more negative valence overall. On the representational maintenance task, individuals with BPD showed less consistency in their representations of self and others over the 3-hr period, but only for abstract, personality-based representations. Performance on this measure mediated between-groups brain activation in several areas supporting social cognition. We found no evidence for social-cognitive disturbance specific to the self. Additionally, the BPD group showed main effects, insensitive to condition, of hyperactivation in the medial prefrontal cortex, temporal parietal junction, several regions of the frontal pole, the precuneus and middle temporal gyrus, all areas crucial social cognition. In contrast, controls evidenced greater activation in visual, sensory, motor, and mirror neuron regions. These findings are discussed in relation to research regarding hypermentalization and the overlap between self- and other-disturbance.

  6. Compliance costs caused by agency action? Empirical evidence and implications for tax compliance

    OpenAIRE

    Eichfelder, Sebastian; Kegels, Chantal

    2012-01-01

    The compliance costs of private taxpayers are not only affected by the tax law itself but also by its implementation through the tax authorities. In this paper we analyze the effect of the tax authorities on the burden of complying with tax regulations. Using survey data of Belgian businesses and controlling for potential endogeneity, we find empirical evidence that tax authority behavior is an important cost driver. According to our estimate, a customer-unfriendly tax administration increase...

  7. Modulation of ethanol-intake by morphine: Evidence for a central site of action

    Energy Technology Data Exchange (ETDEWEB)

    Wild, K.D.; Reid, L.D. (Rensselaer Polytechnic Institute, Troy, NY (USA))

    1990-01-01

    Previous studies have shown that subcutaneous administration of low doses of morphine increase, while subcutaneous naloxone decreases, ethanol-intake in rats. However, the site of action of morphine modulation of ethanol-intake remains unclear. In an attempt to elucidate this issue, seven graded doses of morphine were given intracerebroventricularly to rats 15 min prior to an opportunity to consume water and sweetened alcoholic beverage for 2 hr. Two lower doses of intracerebroventricular morphine reliably increased ethanol-intake, while higher doses decreased intake of water. Preference ratios were reliably increased by morphine doses of 1 {mu}g and higher. The present data provide support for a central site of morphine modulation of ethanol-intake.

  8. Ecosystem health of the Great Barrier Reef: Time for effective management action based on evidence

    Science.gov (United States)

    Brodie, Jon; Pearson, Richard G.

    2016-12-01

    The Great Barrier Reef (GBR) is a World Heritage site off the north-eastern coast of Australia. The GBR is worth A 15-20 billion/year to the Australian economy and provides approximately 64,000 full time jobs. Many of the species and ecosystems of the GBR are in poor condition and continue to decline. The principal causes of the decline are catchment pollutant runoff associated with agricultural and urban land uses, climate change impacts and the effects of fishing. Many important ecosystems of the GBR region are not included inside the boundaries of the World Heritage Area. The current management regime for catchment pollutant runoff and climate change is clearly inadequate to prevent further decline. We propose a refocus of management on a "Greater GBR" (containing not only the major ecosystems and species of the GBR, but also its catchment) and on a set of management actions to halt the decline of the GBR. Proposed actions include: (1) Strengthen management in the areas of the Greater GBR where ecosystems are in good condition, with Torres Strait, northern Cape York and Hervey Bay being the systems with highest current integrity; (2) Investigate methods of cross-boundary management to achieve simultaneous cost-effective terrestrial, freshwater and marine ecosystem protection in the Greater GBR; (3) Develop a detailed, comprehensive, costed water quality management plan for the Greater GBR; (4) Use the Great Barrier Reef Marine Park Act and the Environment Protection and Biodiversity Conservation Act to regulate catchment activities that lead to damage to the Greater GBR, in conjunction with the relevant Queensland legislation; (5) Fund catchment and coastal management to the required level to solve pollution issues for the Greater GBR by 2025, before climate change impacts on Greater GBR ecosystems become overwhelming; (6) Continue enforcement of the zoning plan; (7) Australia to show commitment to protecting the Greater GBR through greenhouse gas emissions

  9. Dopamine depletion affects communicative intentionality in Parkinson's disease patients: Evidence from action kinematics.

    Science.gov (United States)

    Straulino, Elisa; Scaravilli, Tomaso; Castiello, Umberto

    2016-04-01

    Appropriate communication is at the heart of successful, healthy social interactions in humans. Deficits in social communication are a hallmark of several neurological and psychiatric disorders. Yet, very little research has been devoted to understanding the mechanisms underlying these issues. It has been suggested that dopamine is a candidate neurotransmitter system involved in stimulating communication in individuals that are not highly motivated to communicate. A typical model to study dopaminergic dysfunctions in humans is represented by Parkinson's disease (PD) patients, who show motor, cognitive and motivational symptoms. Our study aimed to investigate the effects of social communication on actions in non-demented PD patients receiving dopamine replacement therapy (Levodopa = l-Dopa) and in neurologically healthy control participants. Patients' ability to modulate motor patterning depending on the communicative intention motivating the action to be performed was evaluated both in "on" (with l-Dopa) and "off" (without l-Dopa) states. In two main conditions, participants were requested to reach towards, grasp an object, and either simply lift it (individual condition) or lift it with the intent to communicate a meaning to a partner (communicative condition). Movements' kinematics was recorded using a three-dimensional motion analysis system. The results indicate that kinematics is sensitive to communicative intention and that l-Dopa treatment has positive effects on translating communicative intentions into specific motor patterns in PD patients. Although the to-be-grasped object remained the same both the controls and the PD patients in an 'on' state adopted different kinematic patterning for the 'individual' and the 'communication' conditions. The PD patients in the 'off' state, instead, were unable to kinematically differentiate between the two conditions. We contend that social and communicative impairments are associated with abnormalities in

  10. Evidence for Action on HIV Treatment and Care Systems in low and middle-income countries: background and introduction.

    Science.gov (United States)

    Ross, David A; South, Annabelle; Weller, Ian; Hakim, James

    2012-12-01

    Despite the unprecedented scale-up of treatment for HIV in low and middle-income countries over the past decade, 49% of adults and 77% of children in need of HIV treatment still do not have access to it. ART programmes that were initially set up as an emergency response now need to be adapted to ensure that they include all the essential components and are well integrated with other health services; meet the needs of special groups, including children, adolescents, pregnant women and older people; address the mental health needs of HIV-positive people; and monitor as well as report their impact in valid and comparable ways.This supplement is an output from the Evidence for Action on HIV Treatment and Care Systems research programme consortium. Evidence for Action was a 5-year, multidisciplinary research programme, which ran from 2006 to 2011, with partners in India, Malawi, Uganda, Zambia and the United Kingdom.The primary aim of this supplement is to stimulate reflection and provide guidance on what should be in the package of HIV treatment and care systems, as national programmes look to maintain the major advances of the past decade and scale-up treatment to the other 50% of people in need of it.

  11. Do Bans on Affirmative Action Hurt Minority Students? Evidence from the Texas Top 10% Plan. Upjohn Institute Working Paper No. 10-168

    Science.gov (United States)

    Cortes, Kalena E.

    2010-01-01

    In light of the recent bans on affirmative action in higher education, this paper provides new evidence on the effects of alternative admissions policies on the persistence and college completion of minority students. I find that the change from affirmative action to the Top 10% Plan in Texas decreased both retention and graduation rates of…

  12. [Sustainable Implementation of Evidence-Based Programmes in Health Promotion: A Theoretical Framework and Concept of Interactive Knowledge to Action].

    Science.gov (United States)

    Rütten, A; Wolff, A; Streber, A

    2016-03-01

    This article discusses 2 current issues in the field of public health research: (i) transfer of scientific knowledge into practice and (ii) sustainable implementation of good practice projects. It also supports integration of scientific and practice-based evidence production. Furthermore, it supports utilisation of interactive models that transcend deductive approaches to the process of knowledge transfer. Existing theoretical approaches, pilot studies and thoughtful conceptual considerations are incorporated into a framework showing the interplay of science, politics and prevention practice, which fosters a more sustainable implementation of health promotion programmes. The framework depicts 4 key processes of interaction between science and prevention practice: interactive knowledge to action, capacity building, programme adaptation and adaptation of the implementation context. Ensuring sustainability of health promotion programmes requires a concentrated process of integrating scientific and practice-based evidence production in the context of implementation. Central to the integration process is the approach of interactive knowledge to action, which especially benefits from capacity building processes that facilitate participation and systematic interaction between relevant stakeholders. Intense cooperation also induces a dynamic interaction between multiple actors and components such as health promotion programmes, target groups, relevant organisations and social, cultural and political contexts. The reciprocal adaptation of programmes and key components of the implementation context can foster effectiveness and sustainability of programmes. Sustainable implementation of evidence-based health promotion programmes requires alternatives to recent deductive models of knowledge transfer. Interactive approaches prove to be promising alternatives. Simultaneously, they change the responsibilities of science, policy and public health practice. Existing boundaries

  13. Runway self-administration of intracerebroventricular cocaine: evidence of mixed positive and negative drug actions.

    Science.gov (United States)

    Guzman, Daniel; Ettenberg, Aaron

    2007-02-01

    In previous work from our laboratory, animals running for intravenous cocaine developed a unique approach-avoidance 'retreat behavior' that was hypothesized to result from cocaine's well documented reinforcing (positive) and anxiogenic (negative) properties. To assess the role of central mechanisms in producing cocaine's positive and negative effects, we assessed whether or not animals running a straight alley for intracerebroventricular applications of cocaine would produce a similar behavioral profile to that previously observed with intravenous applications. Retreat frequency and location were measured in male Sprague-Dawley rats trained to run an alley for one of four doses of intracerebroventricular-administered cocaine (0, 25, 50 or 100 microg cocaine/infusion). Testing involved a single trial per day over 14 consecutive days with a single infusion of cocaine delivered upon goal box entry. The 100 and 50 microg intracerebroventricular cocaine groups exhibited significantly higher retreat frequencies than the 25 and 0 microg groups and the nature and magnitude of the behavior was comparable to that previously observed with intravenous cocaine. These results suggest that the intracerebroventricular self-administration of cocaine results in mixed positive and negative consequences and therefore likely stem from the drug's actions within the central nervous system.

  14. Bilingual Children with Primary Language Impairment: Issues, Evidence and Implications for Clinical Actions

    Science.gov (United States)

    Kohnert, Kathryn

    2010-01-01

    A clear understanding of how to best provide clinical serves to bilingual children with suspected or confirmed primary language impairment (PLI) is predicated on understanding typical development in dual-language learners as well as the PLI profile. This article reviews general characteristics of children learning two languages, including three that challenge the diagnosis and treatment of PLI; uneven distribution of abilities in the child's two languages, cross-linguistic associations within bilingual learners, and individual variation in response to similar social circumstances. The diagnostic category of PLI (also referred to in the literature as specific language impairment or SLI) is described with attention to how language impairment, in the face of otherwise typical development, manifests in children learning two languages. Empirical evidence related to differential diagnosis of PLI in bilingual children is then reviewed and issues related to the generalization of treatment gains in dual-language learners with PLI are introduced. PMID:20371080

  15. Differential neural activation for camouflage detection task in Field-independent and Field-Dependent individuals: Evidence from fMRI

    Indian Academy of Sciences (India)

    Janani Rajagopalan; Shilpi Modi; Pawan Kumar; Subash Khushu; Manas K Mandal

    2015-12-01

    It is not clearly known as to why some people identify camouflaged objects with ease compared with others. The literature suggests that Field-Independent individuals detect camouflaged object better than their Field-Dependent counterparts, without having evidence at the neural activation level. A paradigm was designed to obtain neural correlates of camouflage detection, with real-life photographs, using functional magnetic resonance imaging. Twenty-three healthy human subjects were stratified as Field-Independent (Fl) and Field-Dependent (FD), with Witkins Embedded Figure Test. FIs performed better than FDs (marginal significance; =0.054) during camouflage detection task. fMRI revealed differential activation pattern between Fl and FD subjects for this task. One sample T-test showed greater activation in terms of cluster size in FDs, whereas FIs showed additional areas for the same task. On direct comparison of the two groups, Fl subjects showed additional activation in parts of primary visual cortex, thalamus, cerebellum, inferior and middle frontal gyrus. Conversely, FDs showed greater activation in inferior frontal gyms, precentral gyms, putamen, caudate nucleus and superior parietal lobule as compared to FIs. The results give preliminary evidence to the differential neural activation underlying the variances in cognitive styles of the two groups.

  16. Neural response to modulating the probability that actions of self or other result in auditory tones: A parametric fMRI study into causal ambiguity.

    Science.gov (United States)

    de Bézenac, Christophe E; Sluming, Vanessa; Gouws, André; Corcoran, Rhiannon

    2016-09-01

    In normal circumstances we can easily distinguish between changes to the external world brought about by our own actions from those with external causes. However, in certain contexts our sense of ownership and agency over acts is not so clear. Neuroimaging studies have implicated a number of regions in the sense of agency, some of which have been shown to vary continuously with action-outcome discordance. However, little is known about dynamic, ambiguous contexts characterised by a lack of information for self-other differentiation, yet such ambiguous states are important in relation to symptoms and levels of consciousness that characterise certain mental health conditions. With a block-design fMRI paradigm, we investigated neural responses to changes in the probability that a participant's irregular finger taps over 12s would result in auditory tones as opposed to tones generated by 'another's finger taps'. The main findings were that misattribution increased in ambiguous conditions where the probability of a tone belonging to self and other was equal. Task-sensitive brain regions, previously identified in self-agency, motor cognition, and ambiguity processing, showed a quadratic response to our self-to-other manipulation, with particular sensitivity to self-control. Task performance (low error and bias) was related to attenuated response in ambiguous conditions while increased response in regions associated with the default mode network was associated with greater overall error and bias towards other. These findings suggest that causal ambiguity as it occurs over time is a prominent feature in sense of agency, one that may eventually contribute to a more comprehensive understanding of positive symptoms of psychosis.

  17. Bilingual children with primary language impairment: issues, evidence and implications for clinical actions.

    Science.gov (United States)

    Kohnert, Kathryn

    2010-01-01

    A clear understanding of how to best provide clinical serves to bilingual children with suspected or confirmed primary language impairment (PLI) is predicated on understanding typical development in dual-language learners as well as the PLI profile. This article reviews general characteristics of children learning two languages, including three that challenge the diagnosis and treatment of PLI; uneven distribution of abilities in the child's two languages, cross-linguistic associations within bilingual learners, and individual variation in response to similar social circumstances. The diagnostic category of PLI (also referred to in the literature as specific language impairment or SLI) is described with attention to how language impairment, in the face of otherwise typical development, manifests in children learning two languages. Empirical evidence related to differential diagnosis of PLI in bilingual children is then reviewed and issues related to the generalization of treatment gains in dual-language learners with PLI are introduced. As a result of this activity, the careful reader will be able to (1) describe general characteristics of typically developing dual-language learners, (2) explain how primary language impairment (PLI) manifests in bilingual children, and (3) identify key clinical issues and approaches to assessment and treatment on bilingual PLI. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Yoga for the Treatment of Insomnia among Cancer Patients: Evidence, Mechanisms of Action, and Clinical Recommendations.

    Science.gov (United States)

    Mustian, Karen M; Janelsins, Michelle; Peppone, Luke J; Kamen, Charles

    Up to 90% of cancer patients report symptoms of insomnia during and after treatment. Symptoms of insomnia include excessive daytime sleepiness, difficulty falling asleep, difficulty staying asleep, and waking up too early. Insomnia symptoms are among the most prevalent, distressing and persistent cancer- and cancer treatment-related toxicities reported by patients, and can be severe enough to increase cancer morbidity and mortality. Despite the ubiquity of insomnia symptoms, they are under-screened, under-diagnosed, and under-treated in cancer patients. When insomnia symptoms are identified, providers are hesitant to prescribe, and patients are hesitant to take pharmaceuticals due to polypharmacy concerns. In addition, sleep medications do not cure insomnia. Yoga is a well-tolerated mode of exercise with promising evidence for its efficacy in improving insomnia symptoms among cancer patients. This article reviews existing clinical research on the effectiveness of yoga for treating insomnia among cancer patients. The article also provides clinical recommendations for prescribing yoga for the treatment of insomnia in this population.

  19. Evidence from the UK Zoonoses Action Plan in favour of localised anomalies of Salmonella infection on United Kingdom pig farms.

    Science.gov (United States)

    Clough, Helen E; Fenton, Sarah E; French, Nigel P; Miller, Alexander J; Cook, Alasdair J C

    2009-05-01

    Salmonella spp. are important food-borne pathogens. Abattoir studies demonstrated that almost a quarter of British finisher pigs might carry Salmonella, which led to the introduction by the British Pig Executive of their Zoonoses Action Plan (ZAP) to monitor the Salmonella status of United Kingdom pig farms by testing meat juice samples using an ELISA system. We used the K-function and approaches from the field of geostatistics to study routine data from ZAP. We demonstrated that there is statistical evidence that geographically localized anomalies of Salmonella infection were present in one of three regions studied. The physical mechanisms underlying this structure remain unclear: spatial structure might be present as a result of shared spatially structured (second-order) or non-spatially structured (first-order) risk factors, transmission processes, or a combination of both. We have demonstrated a way to use routinely collected surveillance data to enhance the knowledge of spatial disease epidemiology.

  20. The neural correlates of agrammatism: Evidence from aphasic and healthy speakers performing an overt picture description task

    Directory of Open Access Journals (Sweden)

    Eva eSchoenberger

    2014-03-01

    Full Text Available Functional brain imaging studies have improved our knowledge of the neural localization of language functions and the functional recovery after a lesion. However, the neural correlates of agrammatic symptoms in aphasia remain largely unknown. The present fMRI study examined the neural correlates of morpho-syntactic encoding and agrammatic errors in continuous language production by combining three approaches. First, the neural mechanisms underlying natural morpho-syntactic processing in a picture description task were analyzed in 15 healthy speakers. Second, agrammatic-like speech behavior was induced in the same group of healthy speakers to study the underlying functional processes by limiting the utterance length. In a third approach, five agrammatic participants performed the picture description task to gain insights in the neural correlates of agrammatism and the functional reorganization of language processing after stroke. In all approaches, utterances were analyzed for syntactic completeness, complexity and morphology. Event-related data analysis was conducted by defining every clause-like unit (CLU as an event with its onset-time and duration. Agrammatic and correct CLUs were contrasted. Due to the small sample size as well as heterogeneous lesion sizes and sites with lesion foci in the insula lobe, inferior frontal, superior temporal and inferior parietal areas the activation patterns in the agrammatic speakers were analyzed on a single subject level. In the group of healthy speakers, posterior temporal and inferior parietal areas were associated with greater morpho-syntactic demands in complete and complex CLUs. The intentional manipulation of morpho-syntactic structures and the omission of function words were associated with additional inferior frontal activation. Overall, the results revealed that the investigation of the neural correlates of agrammatic language production can be reasonably conducted with an overt language production

  1. The neural correlates of agrammatism: Evidence from aphasic and healthy speakers performing an overt picture description task

    Science.gov (United States)

    Schönberger, Eva; Heim, Stefan; Meffert, Elisabeth; Pieperhoff, Peter; da Costa Avelar, Patricia; Huber, Walter; Binkofski, Ferdinand; Grande, Marion

    2014-01-01

    Functional brain imaging studies have improved our knowledge of the neural localization of language functions and the functional reorganization after a lesion. However, the neural correlates of agrammatic symptoms in aphasia remain largely unknown. The present fMRI study examined the neural correlates of morpho-syntactic encoding and agrammatic errors in continuous language production by combining three approaches. First, the neural mechanisms underlying natural morpho-syntactic processing in a picture description task were analyzed in 15 healthy speakers. Second, agrammatic-like speech behavior was induced in the same group of healthy speakers to study the underlying functional processes by limiting the utterance length. In a third approach, five agrammatic participants performed the picture description task to gain insights in the neural correlates of agrammatism and the functional reorganization of language processing after stroke. In all approaches, utterances were analyzed for syntactic completeness, complexity, and morphology. Event-related data analysis was conducted by defining every clause-like unit (CLU) as an event with its onset-time and duration. Agrammatic and correct CLUs were contrasted. Due to the small sample size as well as heterogeneous lesion sizes and sites with lesion foci in the insula lobe, inferior frontal, superior temporal and inferior parietal areas the activation patterns in the agrammatic speakers were analyzed on a single subject level. In the group of healthy speakers, posterior temporal and inferior parietal areas were associated with greater morpho-syntactic demands in complete and complex CLUs. The intentional manipulation of morpho-syntactic structures and the omission of function words were associated with additional inferior frontal activation. Overall, the results revealed that the investigation of the neural correlates of agrammatic language production can be reasonably conducted with an overt language production paradigm

  2. Direct evidence for two different neural mechanisms for reading familiar and unfamiliar words: an intra-cerebral EEG study

    Directory of Open Access Journals (Sweden)

    Alexandra eJuphard

    2011-09-01

    Full Text Available After intensive practice, unfamiliar letter strings become familiar words and reading speed increases strikingly from a slow processing to a fast and with more global recognition of words. While this effect has been well documented at the behavioral level, its neural underpinnings are still unclear. The question is how the brain modulates the activity of the reading network according to the novelty of the items. Several models have proposed that familiar and unfamiliar words are not processed by separate networks but rather by common regions operating differently according to familiarity. This hypothesis has proved difficult to test at the neural level because the effects of familiarity and length on reading occur (a on a millisecond scale, shorter than the resolution of fMRI and (b in regions which cannot be isolated with non-invasive EEG or MEG. We overcame these limitations by using invasive intra-cerebral EEG recording in epileptic patients. Neural activity (gamma-band responses, GBR, between 50 Hz and 150 Hz was measured in three major nodes of reading network – left inferior frontal, supramarginal and inferior temporo-occipital cortices - while patients silently read familiar (words and unfamiliar (pseudo-words items of two lengths (short composed of one-syllable vs. long composed of three syllables. While all items elicited strong neural responses in the three regions, we found that the duration of the neural response increases with length only for pseudo-words, in direct relation to grapheme-to-phoneme conversion. Our results validate at the neural level the hypothesis that all words are processed by a common network operating more or less efficiently depending on words’ novelty.

  3. Real world evidence: a form of big data, transforming healthcare data into actionable real time insights and informed business decisions

    Directory of Open Access Journals (Sweden)

    Uttam Kumar Barick

    2015-09-01

    Full Text Available Data has always played an important role in assisting business decisions and overall improvement of a company’s strategies. The introduction of what has come to be named ‘BIG data’ has changed the industry paradigm altogether for a few domains like media, mobility, retail and social. Data from the real world is also considered as BIG data based on its magnitude, sources and the industry’s capacity to handle the same. Although, the healthcare industry has been using real world data for decades, digitization of health records has demonstrated its value to all the stakeholders with a reaffirmation of interest in it. Over time, companies are looking to adopt new technologies in linking these fragmented data for meaningful and actionable insights to demonstrate their value over competition. It has also been noticed that the consequences of not demonstrating the value of data are sometimes leads regulators and payers to be severe. The real challenge though is not in identifying data sets but transforming these data sets into actionable real time insights and business decisions. Evidence and value development frameworks need to work side by side, harnessing meaningful insights in parallel to product development from early phase to life-cycle management. This should in-turn create evidence and value-based insights for multiple stakeholders across the industry; ultimately supporting the patient as the end user to take informed decisions that impact access to care. This article attempts to review the current state of affairs in the area of BIG data in pharma OR BIG DIP as it is increasingly being referred to.

  4. Molecular and biochemical evidence for the involvement of calcium/calmodulin in auxin action

    Science.gov (United States)

    Yang, T.; Poovaiah, B. W.

    2000-01-01

    -dependent manner suggests that calcium/CaM regulate ZmSAUR1 at the post-translational level. Our data provide the first direct evidence for the involvement of calcium/CaM-mediated signaling in auxin-mediated signal transduction.

  5. Molecular and biochemical evidence for the involvement of calcium/calmodulin in auxin action

    Science.gov (United States)

    Yang, T.; Poovaiah, B. W.

    2000-01-01

    -dependent manner suggests that calcium/CaM regulate ZmSAUR1 at the post-translational level. Our data provide the first direct evidence for the involvement of calcium/CaM-mediated signaling in auxin-mediated signal transduction.

  6. The Neural Basis of Risk Ratings: Evidence from a Functional Magnetic Resonance Imaging (fMRI) Study

    Science.gov (United States)

    Vorhold, V.; Giessing, C.; Wiedemann, P. M.; Schutz, H.; Gauggel, S.; Fink, G. R.

    2007-01-01

    Research investigating risk perception suggests that not only the quantitative parameters used in technical risk assessment (i.e., frequency and severity of harm) but also "qualitative" aspects such as the dread a hazard provokes or its controllability influence risk judgments. It remains to be elucidated, however, which neural mechanism underlie…

  7. Musicians' Enhanced Neural Differentiation of Speech Sounds Arises Early in Life: Developmental Evidence from Ages 3 to 30

    Science.gov (United States)

    Strait, Dana L.; O'Connell, Samantha; Parbery-Clark, Alexandra; Kraus, Nina

    2014-01-01

    The perception and neural representation of acoustically similar speech sounds underlie language development. Music training hones the perception of minute acoustic differences that distinguish sounds; this training may generalize to speech processing given that adult musicians have enhanced neural differentiation of similar speech syllables compared with nonmusicians. Here, we asked whether this neural advantage in musicians is present early in life by assessing musically trained and untrained children as young as age 3. We assessed auditory brainstem responses to the speech syllables /ba/ and /ga/ as well as auditory and visual cognitive abilities in musicians and nonmusicians across 3 developmental time-points: preschoolers, school-aged children, and adults. Cross-phase analyses objectively measured the degree to which subcortical responses differed to these speech syllables in musicians and nonmusicians for each age group. Results reveal that musicians exhibit enhanced neural differentiation of stop consonants early in life and with as little as a few years of training. Furthermore, the extent of subcortical stop consonant distinction correlates with auditory-specific cognitive abilities (i.e., auditory working memory and attention). Results are interpreted according to a corticofugal framework for auditory learning in which subcortical processing enhancements are engendered by strengthened cognitive control over auditory function in musicians. PMID:23599166

  8. Using Complement Coercion to Understand the Neural Basis of Semantic Composition: Evidence from an fMRI Study

    Science.gov (United States)

    Husband, E. Matthew; Kelly, Lisa A.; Zhu, David C.

    2011-01-01

    Previous research regarding the neural basis of semantic composition has relied heavily on violation paradigms, which often compare implausible sentences that violate world knowledge to plausible sentences that do not violate world knowledge. This comparison is problematic as it may involve extralinguistic operations such as contextual repair and…

  9. Experiencing Past and Future Personal Events: Functional Neuroimaging Evidence on the Neural Bases of Mental Time Travel

    Science.gov (United States)

    Botzung, Anne; Denkova, Ekaterina; Manning, Lilianne

    2008-01-01

    Functional MRI was used in healthy subjects to investigate the existence of common neural structures supporting re-experiencing the past and pre-experiencing the future. Past and future events evocation appears to involve highly similar patterns of brain activation including, in particular, the medial prefrontal cortex, posterior regions and the…

  10. The Neural Basis of Reversible Sentence Comprehension: Evidence from Voxel-Based Lesion Symptom Mapping in Aphasia

    Science.gov (United States)

    Thothathiri, Malathi; Kimberg, Daniel Y.; Schwartz, Myrna F.

    2012-01-01

    We explored the neural basis of reversible sentence comprehension in a large group of aphasic patients (n = 79). Voxel-based lesion symptom mapping revealed a significant association between damage in temporo-parietal cortex and impaired sentence comprehension. This association remained after we controlled for phonological working memory. We…

  11. Scaling up of physical activity interventions in Brazil: how partnerships and research evidence contributed to policy action.

    Science.gov (United States)

    Parra, Diana C; Hoehner, Christine M; Hallal, Pedro C; Reis, Rodrigo S; Simoes, Eduardo J; Malta, Deborah C; Pratt, Michael; Brownson, Ross C

    2013-12-01

    The global health burden due to physical inactivity is enormous and growing. There is a need to consider new ways of generating evidence and to identify the role of government in promoting physical activity at the population level. In this paper, we summarize key findings from a large-scale cross-national collaboration to understand physical activity promotion in Brazil. We describe the main aspects of the partnership of Project GUIA (Guide for Useful Interventions for Activity in Brazil and Latin America) that sustained the collaborative effort for eight years and describe how the evidence gathered from the collaboration triggered political action in Brazil to scale up a physical activity intervention at the national level. Project GUIA is a cross-national multidisciplinary research partnership designed to understand and evaluate current efforts for physical activity promotion at the community level in Latin America. This example of scaling up is unprecedented for promoting health in the region and is an example that must be followed and evaluated.

  12. Mechanisms of action of anesthetics for the modulation of perioperative thrombosis: evidence for immune mechanisms from basic and clinical studies.

    Science.gov (United States)

    Azma, Toshiharu; Tuluc, Florin; Ito, Taishin; Aoyama-Mani, Chikako; Kawahito, Shinji; Kinoshita, Hiroyuki

    2014-01-01

    Thrombotic events occurring in either arteries or veins are the primary causes of fatal perioperative cardiovascular events. Risk factors for deep vein thrombosis, several of which are evidently associated with specific surgical procedures, are quite different from those for arterial thrombosis (e.g., aging or atherosclerotic diseases). Thrombus formed in arteries consists mainly of platelets coated with fibrin (i.e., white thrombus), while venous thrombus formed at relatively lower shear stress consists of all blood components including erythrocytes as well as leukocytes infiltrated with fibrin (red thrombus). Clinical evidence indicates beneficial roles of neuraxial anesthesia/analgesia in the prevention of VTE for patients undergoing high risk surgical procedures. To date, mechanisms of action of drugs used for neuraxial anesthesia/analgesia to prevent venous thrombosis are uncertain. However, accumulation of clinical as well as experimental findings points to the involvement of immune cells (especially monocytes) in red thrombus generation and to the interaction of anesthetics with these cells. We also suggest that adhesion molecules associated with the formation of monocyte platelet aggregates as well as substance P: neurokinin-1 receptor (SP/NK1R) pathway that involves neurogenic inflammation are crucial. Local anesthetics and NK1R antagonists are candidate drugs that may possess the capability to prevent venous thrombotic disorders in perioperative settings.

  13. Is there a domain-general cognitive structuring system? Evidence from structural priming across music, math, action descriptions, and language.

    Science.gov (United States)

    Van de Cavey, Joris; Hartsuiker, Robert J

    2016-01-01

    Cognitive processing in many domains (e.g., sentence comprehension, music listening, and math solving) requires sequential information to be organized into an integrational structure. There appears to be some overlap in integrational processing across domains, as shown by cross-domain interference effects when for example linguistic and musical stimuli are jointly presented (Koelsch, Gunter, Wittfoth, & Sammler, 2005; Slevc, Rosenberg, & Patel, 2009). These findings support theories of overlapping resources for integrational processing across domains (cfr. SSIRH Patel, 2003; SWM, Kljajevic, 2010). However, there are some limitations to the studies mentioned above, such as the frequent use of unnaturalistic integrational difficulties. In recent years, the idea has risen that evidence for domain-generality in structural processing might also be yielded though priming paradigms (cfr. Scheepers, 2003). The rationale behind this is that integrational processing across domains regularly requires the processing of dependencies across short or long distances in the sequence, involving respectively less or more syntactic working memory resources (cfr. SWM, Kljajevic, 2010), and such processing decisions might persist over time. However, whereas recent studies have shown suggestive priming of integrational structure between language and arithmetics (though often dependent on arithmetic performance, cfr. Scheepers et al., 2011; Scheepers & Sturt, 2014), it remains to be investigated to what extent we can also find evidence for priming in other domains, such as music and action (cfr. SWM, Kljajevic, 2010). Experiment 1a showed structural priming from the processing of musical sequences onto the position in the sentence structure (early or late) to which a relative clause was attached in subsequent sentence completion. Importantly, Experiment 1b showed that a similar structural manipulation based on non-hierarchically ordered color sequences did not yield any priming effect

  14. The causes of neural tube defect:evidence-based research%神经管缺陷发生原因的循证医学研究

    Institute of Scientific and Technical Information of China (English)

    谷茜; 刘佳琦; 何达; 葛智馨; 陈英耀; 厉传琳

    2011-01-01

    目的:通过系统性综述的方法,分析神经管缺陷(NTDs)的病因.方法:检索国内外文献数据库,检索时间从建库~2009年12月,纳入神经管缺陷病因学的系统性综述/Meta分析和随机对照试验,中文文献研究设计等级为病例-对照研究.结果:共纳入系统性综述/Meta分析9篇,随机对照试验2篇,病例-对照研究7篇.现有证据显示,遗传方面,MTHFR基因677位点TT基因型是非拉丁裔欧洲人群子代NTDs发生的危险因素;与HCY(同型半胱氨酸)代谢途径有关的酶或基因突变可引起NTDs发生概率增加,具有家族史及NTDs生产史其子代NTDs发病率较高.环境暴露方面,孕妇高热、父亲接触有机溶剂和使用抗癫痫药物(卡马西平和丙戊酸)是NTDs发生的危险因素,现有证据不支持紫外线照射和使用克罗米酚柠檬酸盐影响子代NTDs的发病风险的假设.生活行为方面,孕妇超重或肥胖、多次孕产史是NTDs发生的危险因素,使用IVF辅助生殖技术对NTDs发病的影响仍存在争议.结论:NTDs病因复杂,具有较高证据等级的病因学研究不多,病因仍有待探索.目前在孕早期补充叶酸是被广泛推荐使用的有效干预措施.%Objective: To analyze the causes of neural tube defect by systematic review. Methods: The international and national databases (from establishment to December 2009) were searched, all systematic reviews/Meta analysis and randomized controlled trials researches about the etiology of neural tube defect were included, case - control studies were also supplemented in Chinese literatures. Results: 9 systematic reviews/ Meta analysis researches, 2 randomized controlled trials and 7 case -control studies in Chinese were included. The current evidence suggested that TT genotype in 677 locus of MTHFR gene was a risk factor of neural tube defect of non - Latin European descents from the genetic point of view; the enzymatic mutation and gene mutation related to

  15. Exploring the neural basis of real-life joint action: measuring brain activation during joint table setting with functional near-infrared spectroscopy (fNIRS

    Directory of Open Access Journals (Sweden)

    Johanna eEgetemeir

    2011-09-01

    Full Text Available Many everyday life situations require two or more individuals to execute actions together. Assessing brain activation during naturalistic tasks to uncover relevant processes underlying such real-life joint action situations has remained a methodological challenge. In the present study, we introduce a novel joint action paradigm that enables the assessment of brain activation during real-life joint action tasks using functional near-infrared spectroscopy (fNIRS. We monitored brain activation of participants who coordinated complex actions with a partner sitting opposite them. Participants performed table-setting tasks, either alone (solo action or in cooperation with a partner (joint action, or they observed the partner performing the task (action observation. Comparing joint action and solo action revealed stronger activation (higher [oxy-Hb]-concentration during joint action in a number of areas. Among these were areas in the inferior parietal lobule (IPL that additionally showed an overlap of activation during action observation and solo action. Areas with such a close link between action observation and action execution have been associated with action simulation processes. The magnitude of activation in these IPL areas also varied according to joint action type and its respective demand on action simulation. The results validate fNIRS as an imaging technique for exploring the functional correlates of interindividual action coordination in real-life settings and suggest that coordinating actions in real-life situations requires simulating the actions of the partner.

  16. Evident?

    DEFF Research Database (Denmark)

    Plant, Peter

    2012-01-01

    Quality assurance and evidence in career guidance in Europe are often seen as self-evident approaches, but particular interests lie behind......Quality assurance and evidence in career guidance in Europe are often seen as self-evident approaches, but particular interests lie behind...

  17. Hypertonic saline does not reverse the sodium channel blocking actions of lidocaine: evidence from electrophysiologic and defibrillation studies.

    Science.gov (United States)

    Ujhelyi, M R; Schur, M; Frede, T; Bottorff, M B; Gabel, M; Markel, M L

    1997-01-01

    Studies have shown that increasing extracellular sodium concentration can partially reverse sodium channel blockade. However, there is conflicting in vitro evidence in this regard for lidocaine. The effects of lidocaine on cardiac electrophysiology and defibrillation were studied in a basal and hypernatremic state to determine reversibility of sodium channel blockade. Electrophysiologic studies measured right ventricular effective refractory period at 350 ms pacing cycle length and QRS interval, JT interval, and monophasic action potential duration during sinus rhythm and right ventricular pacing (350 ms cycle length) in 14 pentobarbital-anesthetized swine (25-30 kg). Defibrillation threshold (DFT) was measured by quantitating successful conversion of sustained ventricular fibrillation to normal sinus rhythm. Each pig was randomly assigned to a treatment group with three study phases; group 1 = baseline, lidocaine (20 mg/kg/h), and lidocaine plus placebo (D5W; n = 7); and group 2 = baseline, lidocaine, and lidocaine plus hypertonic saline (2-3 mM/kg/h; n = 7). In groups 1 and 2, lidocaine infused alone significantly (p Lidocaine alone reduced right ventricular action potential duration (APD) in groups 1 and 2 (214 +/- 18 to 206 +/- 20 ms; p lidocaine, DFT and QRS duration values were unaffected (14.7 +/- 5.4 to 16.1 +/- 3.7 J and 103 +/- 12 to 100 +/- 11 ms, respectively). However, APD and JT intervals returned to basal values when hypertonic saline was added to lidocaine (212 +/- 8 to 225 +/- 13; p Lidocaine slowed ventricular conduction velocity and reduced APD. The administration of hypertonic saline to increase extracellular sodium concentrations failed to reverse the effect of lidocaine on conduction-velocity slowing or elevated DFT values. Hypertonic saline did reverse the effects of lidocaine on repolarization parameters. These data suggest that shortening of repolarization is not a mechanism by which lidocaine makes it more difficult to defibrillate the

  18. How and to what end may consciousness contribute to action? Attributing properties of consciousness to an embodied, minimally cognitive artificial neural network

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    Holk eCruse

    2013-06-01

    Full Text Available An artificial neural network called reaCog is described which is based on a decentralized, reactive and embodied architecture to control non-trivial hexapod walking in unpredictable environment (Walknet as well as insect-like navigation (Navinet. In reaCog, these basic networks are extended in such a way that the complete system, reaCog, adopts the capability of inventing new behaviors and - via internal simulation - of planning ahead. This cognitive expansion enables the reactive system to be enriched with additional procedures. Here, we focus on the question to what extent properties of phenomena to be characterized on a different level of description as for example consciousness can be found in this minimally cognitive system. Adopting a monist view, we argue that the phenomenal aspect of mental phenomena can be neglected when discussing the function of such a system. Under this condition, reaCog is discussed to be equipped with properties as are bottom-up and top-down attention, intentions, volition and some aspects of Access Consciousness. These properties have not been explicitly implemented but emerge from the cooperation between the elements of the network. The aspects of access consciousness found in reaCog concern the above mentioned ability to plan ahead and to invent and guide (new actions. Furthermore, global accessibility of memory elements, another aspect characterizing Access Consciousness is realized by this network. reaCog allows for both reactive/automatic control and (access- conscious control of behavior. We discuss examples for interactions between both the reactive domain and the conscious domain. Metacognition or Reflexive Consciousness is not a property of reaCog. Possible expansions are discussed to allow for further properties of Access Consciousness, verbal report on internal states, and for Metacognition. In summary, we argue that already simple networks allow for properties of consciousness if leaving the phenomenal

  19. 9C.08: HEART RATE AS A PREDICTOR OF CARDIOVASCULAR OUTCOMES: NEW EVIDENCE FROM THE ACTION TRIAL DATABASE.

    Science.gov (United States)

    Meredith, P; Elliott, H L

    2015-06-01

    Received wisdom suggests that treatments which reduce heart rate (HR), or avoid cardio-acceleration, are associated with improved cardiovascular (CV) outcomes. However, in the SIGNIFY trial in 12,049 patients with symptomatic angina, a sub-group analysis demonstrated a small but significant increase in the combined risk of CV death or non-fatal MI with the new anti-anginal agent, ivabradine, which is designed to reduce heart rate. The safety and efficacy of the long-acting calcium channel blocker, Nifedipine GITS (an established anti-anginal agent) has been confirmed via the positive results in the placebo-controlled ACTION trial in patients with stable symptomatic coronary artery disease (CAD). This further, retrospective analysis of the ACTION database has evaluated the inter-relationships between baseline HR, and its on-treatment changes, on subsequent cardiovascular outcomes. The retrospective analyses of the ACTION trial were performed for quintiles of HR, using the multivariate Cox proportional hazard model, for baseline HR and the achieved HR after 6 weeks of the trial (by which time titration of both placebo and nifedipine GITS was complete). For baseline HR, the risk in the lowest (HR > 72BPM) for the primary trial endpoint (HR = 0.81 CI 0.70, 0.94); any cardiovascular (CV) event (HR = 0.82 CI 0.70, 0.96); and new onset heart failure (HR = 0.48 CI 0.31, 0.74). No significant differences were apparent for myocardial infarction (MI) or debilitating stroke. In contrast, there was no evidence that on-treatment HR was predictive of outcome: for example, for the primary efficacy endpoint (any CV event, HF, MI and debilitating stroke) the event rates were similar across the quintiles of HR. Correspondingly, there was no significant HR-related treatment effect (comparing nifedipine GITS and placebo). Whilst retrospective analyses must always be interpreted with caution, these results suggest that with "best practice therapy", CV risk is lowest at

  20. Where does brain neural activation in aesthetic responses to visual art occur? Meta-analytic evidence from neuroimaging studies.

    Science.gov (United States)

    Boccia, M; Barbetti, S; Piccardi, L; Guariglia, C; Ferlazzo, F; Giannini, A M; Zaidel, D W

    2016-01-01

    Here we aimed at finding the neural correlates of the general aspect of visual aesthetic experience (VAE) and those more strictly correlated with the content of the artworks. We applied a general activation likelihood estimation (ALE) meta-analysis to 47 fMRI experiments described in 14 published studies. We also performed four separate ALE analyses in order to identify the neural substrates of reactions to specific categories of artworks, namely portraits, representation of real-world-visual-scenes, abstract paintings, and body sculptures. The general ALE revealed that VAE relies on a bilateral network of areas, and the individual ALE analyses revealed different maximal activation for the artworks' categories as function of their content. Specifically, different content-dependent areas of the ventral visual stream are involved in VAE, but a few additional brain areas are involved as well. Thus, aesthetic-related neural responses to art recruit widely distributed networks in both hemispheres including content-dependent brain areas of the ventral visual stream. Together, the results suggest that aesthetic responses are not independent of sensory, perceptual, and cognitive processes.

  1. How the Mastery Rubric for Statistical Literacy Can Generate Actionable Evidence about Statistical and Quantitative Learning Outcomes

    Directory of Open Access Journals (Sweden)

    Rochelle E. Tractenberg

    2016-12-01

    Full Text Available Statistical literacy is essential to an informed citizenry; and two emerging trends highlight a growing need for training that achieves this literacy. The first trend is towards “big” data: while automated analyses can exploit massive amounts of data, the interpretation—and possibly more importantly, the replication—of results are challenging without adequate statistical literacy. The second trend is that science and scientific publishing are struggling with insufficient/inappropriate statistical reasoning in writing, reviewing, and editing. This paper describes a model for statistical literacy (SL and its development that can support modern scientific practice. An established curriculum development and evaluation tool—the Mastery Rubric—is integrated with a new, developmental, model of statistical literacy that reflects the complexity of reasoning and habits of mind that scientists need to cultivate in order to recognize, choose, and interpret statistical methods. This developmental model provides actionable evidence, and explicit opportunities for consequential assessment that serves students, instructors, developers/reviewers/accreditors of a curriculum, and institutions. By supporting the enrichment, rather than increasing the amount, of statistical training in the basic and life sciences, this approach supports curriculum development, evaluation, and delivery to promote statistical literacy for students and a collective quantitative proficiency more broadly.

  2. Facilitation effect of observed motor deviants in a cooperative motor task: Evidence for direct perception of social intention in action.

    Science.gov (United States)

    Quesque, François; Delevoye-Turrell, Yvonne; Coello, Yann

    2016-01-01

    Spatiotemporal parameters of voluntary motor action may help optimize human social interactions. Yet it is unknown whether individuals performing a cooperative task spontaneously perceive subtly informative social cues emerging through voluntary actions. In the present study, an auditory cue was provided through headphones to an actor and a partner who faced each other. Depending on the pitch of the auditory cue, either the actor or the partner were required to grasp and move a wooden dowel under time constraints from a central to a lateral position. Before this main action, the actor performed a preparatory action under no time constraint, consisting in placing the wooden dowel on the central location when receiving either a neutral ("prêt"-ready) or an informative auditory cue relative to who will be asked to perform the main action (the actor: "moi"-me, or the partner: "lui"-him). Although the task focused on the main action, analysis of motor performances revealed that actors performed the preparatory action with longer reaction times and higher trajectories when informed that the partner would be performing the main action. In this same condition, partners executed the main actions with shorter reaction times and lower velocities, despite having received no previous informative cues. These results demonstrate that the mere observation of socially driven motor actions spontaneously influences the low-level kinematics of voluntary motor actions performed by the observer during a cooperative motor task. These findings indicate that social intention can be anticipated from the mere observation of action patterns.

  3. The Smoke around Mirror Neurons: Goals as Sociocultural and Emotional Organizers of Perception and Action in Learning

    Science.gov (United States)

    Immordino-Yang, Mary Helen

    2008-01-01

    From the pragmatists to the neo-Piagetians, development has been understood to involve cycles of perception and action--the internalization of interactions with the world and the construction of skills for acting in the world. From a neurobiological standpoint, new evidence suggests that neural activities related to action and perception converge…

  4. The Smoke around Mirror Neurons: Goals as Sociocultural and Emotional Organizers of Perception and Action in Learning

    Science.gov (United States)

    Immordino-Yang, Mary Helen

    2008-01-01

    From the pragmatists to the neo-Piagetians, development has been understood to involve cycles of perception and action--the internalization of interactions with the world and the construction of skills for acting in the world. From a neurobiological standpoint, new evidence suggests that neural activities related to action and perception converge…

  5. Evidence for increased SOX3 dosage as a risk factor for X-linked hypopituitarism and neural tube defects.

    Science.gov (United States)

    Bauters, Marijke; Frints, Suzanna G; Van Esch, Hilde; Spruijt, Liesbeth; Baldewijns, Marcella M; de Die-Smulders, Christine E M; Fryns, Jean-Pierre; Marynen, Peter; Froyen, Guy

    2014-08-01

    Genomic duplications of varying lengths at Xq26-q27 involving SOX3 have been described in families with X-linked hypopituitarism. Using array-CGH we detected a 1.1 Mb microduplication at Xq27 in a large family with three males suffering from X-linked hypopituitarism. The duplication was mapped from 138.7 to 139.8 Mb, harboring only two annotated genes, SOX3 and ATP11C, and was shown to be a direct tandem copy number gain. Unexpectedly, the microduplication did not fully segregate with the disease in this family suggesting that SOX3 duplications have variable penetrance for X-linked hypopituitarism. In the same family, a female fetus presenting with a neural tube defect was also shown to carry the SOX3 copy number gain. Since we also demonstrated increased SOX3 mRNA levels in amnion cells derived from an unrelated t(X;22)(q27;q11) female fetus with spina bifida, we propose that increased levels of SOX3 could be a risk factor for neural tube defects.

  6. Mind your errors: evidence for a neural mechanism linking growth mind-set to adaptive posterror adjustments.

    Science.gov (United States)

    Moser, Jason S; Schroder, Hans S; Heeter, Carrie; Moran, Tim P; Lee, Yu-Hao

    2011-12-01

    How well people bounce back from mistakes depends on their beliefs about learning and intelligence. For individuals with a growth mind-set, who believe intelligence develops through effort, mistakes are seen as opportunities to learn and improve. For individuals with a fixed mind-set, who believe intelligence is a stable characteristic, mistakes indicate lack of ability. We examined performance-monitoring event-related potentials (ERPs) to probe the neural mechanisms underlying these different reactions to mistakes. Findings revealed that a growth mind-set was associated with enhancement of the error positivity component (Pe), which reflects awareness of and allocation of attention to mistakes. More growth-minded individuals also showed superior accuracy after mistakes compared with individuals endorsing a more fixed mind-set. It is critical to note that Pe amplitude mediated the relationship between mind-set and posterror accuracy. These results suggest that neural mechanisms indexing on-line awareness of and attention to mistakes are intimately involved in growth-minded individuals' ability to rebound from mistakes.

  7. Theory of Mind and the Whole Brain Functional Connectivity: Behavioral and Neural Evidences with the Amsterdam Resting State Questionnaire.

    Science.gov (United States)

    Marchetti, Antonella; Baglio, Francesca; Costantini, Isa; Dipasquale, Ottavia; Savazzi, Federica; Nemni, Raffaello; Sangiuliano Intra, Francesca; Tagliabue, Semira; Valle, Annalisa; Massaro, Davide; Castelli, Ilaria

    2015-01-01

    A topic of common interest to psychologists and philosophers is the spontaneous flow of thoughts when the individual is awake but not involved in cognitive demands. This argument, classically referred to as the "stream of consciousness" of James, is now known in the psychological literature as "Mind-Wandering." Although of great interest, this construct has been scarcely investigated so far. Diaz et al. (2013) created the Amsterdam Resting State Questionnaire (ARSQ), composed of 27 items, distributed in seven factors: discontinuity of mind, theory of mind (ToM), self, planning, sleepiness, comfort, and somatic awareness. The present study aims at: testing psychometric properties of the ARSQ in a sample of 670 Italian subjects; exploring the neural correlates of a subsample of participants (N = 28) divided into two groups on the basis of the scores obtained in the ToM factor. Results show a satisfactory reliability of the original factional structure in the Italian sample. In the subjects with a high mean in the ToM factor compared to low mean subjects, functional MRI revealed: a network (48 nodes) with higher functional connectivity (FC) with a dominance of the left hemisphere; an increased within-lobe FC in frontal and insular lobes. In both neural and behavioral terms, our results support the idea that the mind, which does not rest even when explicitly asked to do so, has various and interesting mentalistic-like contents.

  8. THEORY OF MIND AND THE WHOLE BRAIN FUNCTIONAL CONNECTIVITY: BEHAVIORAL AND NEURAL EVIDENCES WITH THE AMSTERDAM RESTING STATE QUESTIONNAIRE

    Directory of Open Access Journals (Sweden)

    ANTONELLA eMARCHETTI

    2015-12-01

    Full Text Available A topic of common interest to psychologists and philosophers is the spontaneous flow of thoughts when the individual is awake but not involved in cognitive demands. This argument, classically referred to as the stream of consciousness of James, is now known in the psychological literature as Mind-Wandering. Although of great interest, this construct has been scarcely investigated so far. Diaz and colleagues (2013 created the Amsterdam Resting State Questionnaire (ARSQ, composed of 27 items, distributed in seven factors: discontinuity of mind, theory of mind (ToM, self, planning, sleepiness, comfort and somatic awareness. The present study aims at: testing psychometric properties of the ARSQ in a sample of 670 Italian subjects; exploring the neural correlates of a subsample of participants (N=28 divided into two groups on the basis of the scores obtained in the ToM factor. Results show a satisfactory reliability of the original factional structure in the Italian sample. In the subjects with a high mean in the ToM factor compared to low mean subjects, functional MRI revealed: a network (48 nodes with higher functional connectivity (FC with a dominance of the left hemisphere; an increased within-lobe FC in frontal and insular lobes. In both neural and behavioral terms, our results support the idea that the mind, which does not rest even when explicitly asked to do so, has various and interesting mentalistic-like contents.

  9. Preliminary Evidence for Impaired Brain Activity of Neural Reward Processing in Children and Adolescents with Reactive Attachment Disorder.

    Science.gov (United States)

    Tomoda, Akemi

    2016-01-01

    Childhood maltreatment, which markedly increases risks for psychopathology, is associated with structural and functional brain differences. Especially, exposure to parental verbal abuse (PVA) or interparental violence during childhood is associated with negative outcomes such as depression, posttraumatic stress disorder (PTSD), and reduced cognitive abilities. Other forms of childhood maltreatment have been associated with brain structure or developmental alteration. Our earlier studies elucidated potential discernible effects of PVA and witnessing domestic violence during childhood on brain morphology, including gray matter volume or cortical thickness. Brain regions that process and convey the adverse sensory input of the abuse might be modified specifically by such experiences, particularly in subjects exposed to a single type of maltreatment. Exposure to multiple types of maltreatment is more commonly associated with morphological alterations in the corticolimbic regions. These findings fit with preclinical studies showing that sensory cortices are highly plastic structures. Using tasks with high and low monetary rewards while subjects underwent functional MRI, we also examined whether neural activity during reward processing was altered, or not, in children and adolescents with reactive attachment disorder (RAD). Significantly reduced activity in the caudate and nucleus accumbens was observed during a high monetary reward condition in the RAD group compared to the typically developed group. The striatal neural reward activity in the RAD group was also markedly decreased. The present results suggest that dopaminergic dysfunction occurred in the striatum in children and adolescents with RAD, potentially leading to a future risk of psychiatric disorders such as dependence.

  10. Evidence for the embodiment of space perception: Concurrent hand but not arm action moderates reachability and egocentric distance perception.

    Directory of Open Access Journals (Sweden)

    Stephane eGrade

    2015-06-01

    Full Text Available The perception of reachability (i.e., whether an object is within reach relies on body representations and action simulation. Similarly, egocentric distance estimation (i.e., the perception of the distance an object is from the self is thought to be partly derived from embodied action simulation. Although motor simulation is important for both, it is unclear whether the cognitive processes underlying these behaviors rely on the same motor processes. To investigate this, we measured the impact of a motor interference dual-task paradigm on reachability judgment, egocentric distance estimation, and allocentric length estimation (i.e., how distant two stimuli are from each other independent from the self used as a control task. Participants were required to make concurrent actions with either hand actions of foam ball grip squeezing or arm actions of weight lifting, or no concurrent actions. Results showed that concurrent squeeze actions significantly slowed response speed in the reachability judgment and egocentric distance estimation tasks, but that there was no impact of the concurrent actions on allocentric length estimation. Together, these results suggest that reachability and distance perception, both egocentric perspective tasks, and in contrast to the allocentric perspective task, involve action simulation cognitive processes. The results are discussed in terms of the implication of action simulation when evaluating the position of a target relative to the observer’s body, supporting an embodied view of spatial cognition.

  11. Designer Self-Assemble Peptides Maximize the Therapeutic Benefits of Neural Stem Cell Transplantation for Alzheimer's Disease via Enhancing Neuron Differentiation and Paracrine Action.

    Science.gov (United States)

    Cui, Guo-hong; Shao, Shui-jin; Yang, Jia-jun; Liu, Jian-ren; Guo, Hai-dong

    2016-03-01

    The neuropathological hallmarks of Alzheimer's disease (AD) include the presence of extracellular amyloid-β peptide (Aβ) in the form of amyloid plaques and neuronal loss. Neural stem cell (NSC) is being scrutinized as a promising cell replacement therapy for various neurodegenerative diseases. However, the unfavorable niche at the site of degenerative disease is hostile to the survival and differentiation of transplanted cells. Here, we undertook in vitro and in vivo works to examine whether a designer self-assemble peptide (DSP), which contains one functional domain Tyr-Ile-Gly-Ser-Arg (YIGSR) derived from laminin, promotes the survival and neuronal differentiation of NSC and behavioral improvement. We found that DSP could undergo spontaneous assembly into well-ordered nanofibers, and it not only facilitated the cell viability in normal culture condition, but also decreased the number of apoptotic cells induced by Aβ in vitro. NSC seeded in DSP showed much more neuronal differentiation than that seeded in self-assemble peptide (SP) or alone. In the AD model, NSC transplantation in DSP-treated AD rats demonstrated much more obvious cognitive rescue with restoration of learning/memory function compared with NSC transplantation in SP, NSC alone, or DSP alone treated ones. Interestingly, DSP enhanced the survival and neuronal differentiation of transplanted NSC. Apoptosis levels in the CA1 region and Aβ level in the hippocampus were significantly decreased in the group of NSC transplantation in DSP. Moreover, synaptic function, indicated by the expression of pre-synaptic protein synapsin-1, was restored and the secretion of anti-inflammatory and neurotrophic factors were increased, such as IL-10, brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), and insulin-like growth factor 1 (IGF-1), while the expression of pro-inflammatory factors were decreased, such as TNF-α and IL-1β. These data firstly unveiled that the biomaterial DSP can

  12. Stronger Discounting of External Cause by Action in Human Adults: Evidence for an Action-Based Hypothesis of Visual Collision Perception

    Science.gov (United States)

    Mitsumatsu, Hidemichi

    2013-01-01

    When an actor performs an action on an external object, the actor feels that he or she is exerting a force on that object. By extension, when an observer views a collision between 2 objects, he or she is able to perceive the force that is exerted on the objects during the collision. The latter case is puzzling, as force is not a visual feature per…

  13. The impact of social action funds on child health in a conflict affected country: evidence from Angola.

    Science.gov (United States)

    Djimeu, Eric W

    2014-04-01

    Although recent evidence shows significant and long-lasting detrimental effects of armed conflict on child health, there is lack of studies rigorously assessing the effectiveness of different social and economic development interventions aiming to mitigate the impact of armed conflict on child health. In order to fill this knowledge gap, this study assesses the impact of health projects and water, sanitation, and waste management interventions financed by the Angola Social Action Fund (ASAF) from 1994 to 2001 on child health. I use data from Inquérito aos Agregados Familiares sobre Despesas e Receitas 2000/2001(IDR 2001), a household survey on expenditures and incomes conducted between February 2000 and February 2001 in Angola. IDR 2001 uses a stratified sampling design in which 12 households were surveyed in a random fashion in each aldeia (village) in rural areas and bairro (neighborhood) in urban areas. Using propensity score matching, a fixed effects model, and propensity-based weighted regression, I find that ASAF leads to a statistically significant increase of the height-for-age Z-scores (HAZ) by 0.335 standard deviations of children less than 5 years. This finding is robust to different implementations of the propensity score model specification and when conducting the sensitivity analysis of hidden bias. The main result that emerges from an analysis of heterogeneous effects shows that ASAF has no impact on children living in war displaced households. Despite many challenges faced by conflict affected countries, social funds which are one the key instruments of the World Bank used to promote development at the local level can be used to mitigate the impact of armed conflict on child health. For children living in war displaced households, specific interventions should be designed to mitigate the impact of armed conflict. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Binding Action and Emotion in Social Understanding

    Science.gov (United States)

    Ferri, Francesca; Ebisch, Sjoerd J. H.; Costantini, Marcello; Salone, Anatolia; Arciero, Giampiero; Mazzola, Viridiana; Ferro, Filippo Maria; Romani, Gian Luca; Gallese, Vittorio

    2013-01-01

    In social life actions are tightly linked with emotions. The integration of affective- and action-related information has to be considered as a fundamental component of appropriate social understanding. The present functional magnetic resonance imaging study aimed at investigating whether an emotion (Happiness, Anger or Neutral) dynamically expressed by an observed agent modulates brain activity underlying the perception of his grasping action. As control stimuli, participants observed the same agent either only expressing an emotion or only performing a grasping action. Our results showed that the observation of an action embedded in an emotional context (agent’s facial expression), compared with the observation of the same action embedded in a neutral context, elicits higher neural response at the level of motor frontal cortices, temporal and occipital cortices, bilaterally. Particularly, the dynamic facial expression of anger modulates the re-enactment of a motor representation of the observed action. This is supported by the evidence that observing actions embedded in the context of anger, but not happiness, compared with a neutral context, elicits stronger activity in the bilateral pre-central gyrus and inferior frontal gyrus, besides the pre-supplementary motor area, a region playing a central role in motor control. Angry faces not only seem to modulate the simulation of actions, but may also trigger motor reaction. These findings suggest that emotions exert a modulatory role on action observation in different cortical areas involved in action processing. PMID:23349792

  15. The neural substrates of response inhibition to negative information across explicit and implicit tasks in GAD patients: Electrophysiological evidence from an ERP study

    Directory of Open Access Journals (Sweden)

    Fengqiong eYu

    2015-03-01

    Full Text Available Background: It has been established that the inability to inhibit a response to negative stimuli is the genesis of anxiety. However, the neural substrates of response inhibition to sad faces across explicit and implicit tasks in general anxiety disorder (GAD patients remain unclear.Methods: Electrophysiological data were recorded when subjects performed two modified emotional go/no-go tasks in which neutral and sad faces were presented: one task was explicit (emotion categorization, and the other task was implicit (gender categorization.Results: In the explicit task, electrophysiological evidence showed decreased amplitudes of no-go/go difference waves at the N2 interval in the GAD group compared to the control group. However, in the implicit task, the amplitudes of no-go/go difference waves at the N2 interval showed a reversed trend. Source localization analysis on no-go/N2 components revealed a decreased current source density (CSD in the right dorsal lateral prefrontal cortex in GAD individuals relative to controls. In the implicit task, the left superior temporal gyrus and the left inferior parietal lobe showed enhanced activation in GAD individuals and may compensate for the dysfunction of the right dorsal lateral prefrontal cortex.Conclusions: These findings indicated that the processing of response inhibition to socially sad faces in GAD individuals was interrupted in the explicit task. However, this processing was preserved in the implicit task. The neural substrates of response inhibition to sad faces were dissociated between implicit and explicit tasks.

  16. Aging and decision making under uncertainty: behavioral and neural evidence for the preservation of decision making in the absence of learning in old age.

    Science.gov (United States)

    Hosseini, S M Hadi; Rostami, Maryam; Yomogida, Yukihito; Takahashi, Makoto; Tsukiura, Takashi; Kawashima, Ryuta

    2010-10-01

    Decision making under uncertainty is an essential component of everyday life. Recent psychological studies suggest that older adults, despite age-related neurological decline, can make advantageous decisions when information about the contingencies of the outcomes is available. In this study, a two-choice prediction paradigm has been used, in conjunction with functional magnetic resonance imaging (fMRI), to investigate the effects of normal aging on neural substrates underlying uncertain decision making in the absence of learning that have not been addressed in previous neuroimaging studies. Neuroimaging results showed that both the healthy older and young adults recruited a network of brain regions comprising the right dorsolateral prefrontal cortex, bilateral inferior parietal lobule, medial frontal cortex, and right lateral orbitofrontal cortex during the prediction task. As was hypothesized, the performance of older adults in the prediction task was not impaired compared to young adults. Although no significant age-related increases in brain activity have been found, we observed an age-related decrease in activity in the right inferior parietal lobule. We speculate that the observed age-related decrease in parietal activity could be explained by age-related differences in decision making behavior revealed by questionnaire results and maximizing scores. Together, this study demonstrates behavioral and neural evidence for the preservation of decision making in older adults when information about the contingencies of the outcome is available.

  17. No neural evidence of statistical learning during exposure to artificial languages in children with autism spectrum disorders.

    Science.gov (United States)

    Scott-Van Zeeland, Ashley A; McNealy, Kristin; Wang, A Ting; Sigman, Marian; Bookheimer, Susan Y; Dapretto, Mirella

    2010-08-15

    Language delay is a hallmark feature of autism spectrum disorders (ASD). The identification of word boundaries in continuous speech is a critical first step in language acquisition that can be accomplished via statistical learning and reliance on speech cues. Importantly, early word segmentation skills have been shown to predict later language development in typically developing (TD) children. Here we investigated the neural correlates of online word segmentation in children with and without ASD with a well-established behavioral paradigm previously validated for functional magnetic resonance imaging. Eighteen high-functioning boys with ASD and 18 age- and IQ-matched TD boys underwent functional magnetic resonance imaging while listening to two artificial languages (containing statistical or statistical + prosodic cues to word boundaries) and a random speech stream. Consistent with prior findings, in TD control subjects, activity in fronto-temporal-parietal networks decreased as the number of cues to word boundaries increased. The ASD children, however, did not show this facilitatory effect. Furthermore, statistical contrasts modeling changes in activity over time identified significant learning-related signal increases for both artificial languages in basal ganglia and left temporo-parietal cortex only in TD children. Finally, the level of communicative impairment in ASD children was inversely correlated with signal increases in these same regions during exposure to the artificial languages. This is the first study to demonstrate significant abnormalities in the neural architecture subserving language-related learning in ASD children and to link the communicative impairments observed in this population to decreased sensitivity to the statistical and speech cues available in the language input. Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  18. Evolvable Neural Software System

    Science.gov (United States)

    Curtis, Steven A.

    2009-01-01

    The Evolvable Neural Software System (ENSS) is composed of sets of Neural Basis Functions (NBFs), which can be totally autonomously created and removed according to the changing needs and requirements of the software system. The resulting structure is both hierarchical and self-similar in that a given set of NBFs may have a ruler NBF, which in turn communicates with other sets of NBFs. These sets of NBFs may function as nodes to a ruler node, which are also NBF constructs. In this manner, the synthetic neural system can exhibit the complexity, three-dimensional connectivity, and adaptability of biological neural systems. An added advantage of ENSS over a natural neural system is its ability to modify its core genetic code in response to environmental changes as reflected in needs and requirements. The neural system is fully adaptive and evolvable and is trainable before release. It continues to rewire itself while on the job. The NBF is a unique, bilevel intelligence neural system composed of a higher-level heuristic neural system (HNS) and a lower-level, autonomic neural system (ANS). Taken together, the HNS and the ANS give each NBF the complete capabilities of a biological neural system to match sensory inputs to actions. Another feature of the NBF is the Evolvable Neural Interface (ENI), which links the HNS and ANS. The ENI solves the interface problem between these two systems by actively adapting and evolving from a primitive initial state (a Neural Thread) to a complicated, operational ENI and successfully adapting to a training sequence of sensory input. This simulates the adaptation of a biological neural system in a developmental phase. Within the greater multi-NBF and multi-node ENSS, self-similar ENI s provide the basis for inter-NBF and inter-node connectivity.

  19. Evidence of mirror neurons in human inferior frontal gyrus.

    Science.gov (United States)

    Kilner, James M; Neal, Alice; Weiskopf, Nikolaus; Friston, Karl J; Frith, Chris D

    2009-08-12

    There is much current debate about the existence of mirror neurons in humans. To identify mirror neurons in the inferior frontal gyrus (IFG) of humans, we used a repetition suppression paradigm while measuring neural activity with functional magnetic resonance imaging. Subjects either executed or observed a series of actions. Here we show that in the IFG, responses were suppressed both when an executed action was followed by the same rather than a different observed action and when an observed action was followed by the same rather than a different executed action. This pattern of responses is consistent with that predicted by mirror neurons and is evidence of mirror neurons in the human IFG.

  20. Left occipitotemporal cortex contributes to the discrimination of tool-associated hand actions: fMRI and TMS evidence

    Directory of Open Access Journals (Sweden)

    Francesca ePerini

    2014-08-01

    Full Text Available Functional neuroimaging studies have implicated the left lateral occipitotemporal cortex (LOTC in both tool and hand perception but the functional role of this region is not fully known. Here, by using a task manipulation, we tested whether tool-/hand-selective LOTC contributes to the discrimination of tool-associated hand actions. Participants viewed briefly presented pictures of kitchen and garage tools while they performed one of two tasks: in the action task, they judged whether the tool is associated with a hand rotation action (e.g., screwdriver or a hand squeeze action (e.g., garlic press, while in the location task they judged whether the tool is typically found in the kitchen (e.g., garlic press or in the garage (e.g., screwdriver. Both tasks were performed on the same stimulus set and were matched for difficulty. Contrasting fMRI responses between these tasks showed stronger activity during the action task than the location task in both tool- and hand-selective LOTC regions, which closely overlapped. No differences were found in nearby object- and motion-selective control regions. Importantly, these findings were confirmed by a TMS study, which showed that effective TMS over the tool-/hand-selective LOTC region significantly slowed responses for tool action discriminations relative to tool location discriminations, with no such difference during sham TMS. We conclude that left LOTC contributes to the discrimination of tool-associated hand actions.

  1. Neural processing of recollection, familiarity and priming at encoding: evidence from a forced-choice recognition paradigm.

    Science.gov (United States)

    Meng, Yingfang; Ye, Xiaohong; Gonsalves, Brian D

    2014-10-17

    The distinction between neural mechanisms of explicit and implicit expressions of memory has been well studied at the retrieval stage, but less at encoding. In addition, dissociations obtained in many studies are complicated by methodological difficulties in obtaining process-pure measures of different types of memory. In this experiment, we applied a subsequent memory paradigm and a two-stage forced-choice recognition test to classify study ERP data into four categories: subsequent remembered (later retrieved accompanied by detailed information), subsequent known (later retrieved accompanied by a feeling of familiarity), subsequent primed (later retrieved without conscious awareness) and subsequent forgotten (not retrieved). Differences in subsequent memory effects (DM effects) were measured by comparing ERP waveform associated with later memory based on recollection, familiarity or priming with ERP waveform for later forgotten items. The recollection DM effect involved a robust sustained (onset at 300 ms) prefrontal positive-going DM effect which was right-lateralized, and a later (onset at 800 ms) occipital negative-going DM effect. Familiarity involved an earlier (300-400 ms) prefrontal positive-going DM effect and a later (500-600 ms) parietal positive-going DM effect. Priming involved a negative-going DM effect which onset at 600 ms, mainly distributed over anterior brain sites. These results revealed a sequence of components that represented cognitive processes underlying the encoding of verbal information into episodic memory, and separately supported later remembering, knowing and priming.

  2. Overlap between the neural correlates of cued recall and source memory: evidence for a generic recollection network?

    Science.gov (United States)

    Hayama, Hiroki R.; Vilberg, Kaia L.

    2012-01-01

    Recall of a studied item and retrieval of its encoding context (source memory) both depend upon recollection of qualitative information about the study episode. The present study investigated whether recall and source memory engage overlapping neural regions. Subjects (N=18) studied a series of words which were presented either to the left or right of fixation. fMRI data were collected during a subsequent test phase in which three-letter word stems were presented, two-thirds of which could be completed by a study item. Instructions were to use each stem as a cue to recall a studied word and, when recall was successful, to indicate the word’s study location. When recall failed, the stem was to be completed with the first word to come to mind. Relative to stems for which recall failed, word stems eliciting successful recall were associated with enhanced activity in a variety of cortical regions, including bilateral parietal, posterior midline, and parahippocampal cortex. Activity in these regions was enhanced when recall was accompanied by successful rather than unsuccessful source retrieval. It is proposed that the regions form part of a ‘recollection network’ in which activity is graded according to the amount of information retrieved about a study episode. PMID:22288393

  3. Neural networks involved in mathematical thinking: evidence from linear and non-linear analysis of electroencephalographic activity.

    Science.gov (United States)

    Micheloyannis, Sifis; Sakkalis, Vagelis; Vourkas, Michalis; Stam, Cornelis J; Simos, Panagiotis G

    2005-01-20

    Using linear and non-linear methods, electroencephalographic (EEG) signals were measured at various brain regions to provide information regarding patterns of local and coordinated activity during performance of three arithmetic tasks (number comparison, single-digit multiplication, and two-digit multiplication) and two control tasks that did not require arithmetic operations. It was hypothesized that these measures would reveal the engagement of local and increasingly complex cortical networks as a function of task specificity and complexity. Results indicated regionally increased neuronal signalling as a function of task complexity at frontal, temporal and parietal brain regions, although more robust task-related changes in EEG-indices of activation were derived over the left hemisphere. Both linear and non-linear indices of synchronization among EEG signals recorded from over different brain regions were consistent with the notion of more "local" processing for the number comparison task. Conversely, multiplication tasks were associated with a widespread pattern of distant signal synchronizations, which could potentially indicate increased demands for neural networks cooperation during performance of tasks that involve a greater number of cognitive operations.

  4. Normal perception of Mooney faces in developmental prosopagnosia: Evidence from the N170 component and rapid neural adaptation.

    Science.gov (United States)

    Towler, John; Gosling, Angela; Duchaine, Bradley; Eimer, Martin

    2016-03-01

    Individuals with developmental prosopagnosia (DP) have a severe difficulty recognizing the faces of known individuals in the absence of any history of neurological damage. These recognition problems may be linked to selective deficits in the holistic/configural processing of faces. We used two-tone Mooney images to study the processing of faces versus non-face objects in DP when it is based on holistic information (or the facial gestalt) in the absence of obvious local cues about facial features. A rapid adaptation procedure was employed for a group of 16 DPs. Naturalistic photographs of upright faces were preceded by upright or inverted Mooney faces or by Mooney houses. DPs showed face-sensitive N170 components in response to Mooney faces versus houses, and N170 amplitude reductions for inverted as compared to upright Mooney faces. They also showed the typical pattern of N170 adaptation effects, with reduced N170 components when upright naturalistic test faces were preceded by upright Mooney faces, demonstrating that the perception of Mooney and naturalistic faces recruits shared neural populations. Our findings demonstrate that individuals with DP can utilize global information about face configurations for categorical discriminations between faces and non-face objects, and suggest that face processing deficits emerge primarily at more fine-grained higher level stages of face perception.

  5. Structure and Mutagenesis of Neural Cell Adhesion Molecule Domains Evidence for Flexibility in the Placement of Polysialic Acid Attachment Sites

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Deirdre A.; Swartzentruber, Kristin G.; Lavie, Arnon; Colley, Karen J. (UICM)

    2010-11-09

    The addition of {alpha}2,8-polysialic acid to the N-glycans of the neural cell adhesion molecule, NCAM, is critical for brain development and plays roles in synaptic plasticity, learning and memory, neuronal regeneration, and the growth and invasiveness of cancer cells. Our previous work indicates that the polysialylation of two N-glycans located on the fifth immunoglobulin domain (Ig5) of NCAM requires the presence of specific sequences in the adjacent fibronectin type III repeat (FN1). To understand the relationship of these two domains, we have solved the crystal structure of the NCAM Ig5-FN1 tandem. Unexpectedly, the structure reveals that the sites of Ig5 polysialylation are on the opposite face from the FN1 residues previously found to be critical for N-glycan polysialylation, suggesting that the Ig5-FN1 domain relationship may be flexible and/or that there is flexibility in the placement of Ig5 glycosylation sites for polysialylation. To test the latter possibility, new Ig5 glycosylation sites were engineered and their polysialylation tested. We observed some flexibility in glycosylation site location for polysialylation and demonstrate that the lack of polysialylation of a glycan attached to Asn-423 may be in part related to a lack of terminal processing. The data also suggest that, although the polysialyltransferases do not require the Ig5 domain for NCAM recognition, their ability to engage with this domain is necessary for polysialylation to occur on Ig5 N-glycans.

  6. Short historical survey of pattern formation in the endo-mesoderm and the neural anlage in the vertebrates: the role of vertical and planar inductive actions.

    Science.gov (United States)

    Nieuwkoop, P D

    1997-04-01

    After some introductory remarks about vertical versus horizontal inductive interactions and about planar versus homoiogenetic induction, the author discusses: a) the historical development of the more recently studied endo-mesoderm induction in the Urodeles and in the anuran Xenopus laevis, b) the possible causal relationship between endo-mesoderm induction and the initiation of the gastrulation process, and c) the older history of the regional neural induction as initially studied in the Urodeles and only recently analysed in the anuran Xenopus laevis. The essential vertical interaction in the neural induction process both in urodelian and in anuran amphibians is emphasized.

  7. Perception-Action in children with ASD

    Directory of Open Access Journals (Sweden)

    Claes eVon Hofsten

    2012-12-01

    Full Text Available How do disturbances to perception and action relate to the deficiencies expressed by children with autism? The ability to predict what is going to happen next is crucial for the construction of all actions and children develop these predictive abilities early in development. Children with autism, however, are deficient in the ability to foresee future events and to plan movements and movement sequences. They are also deficient in the understanding of other people’s actions. This includes communicative actions as they are ultimately based on movements. Today there are two promising neurobiological interpretation of ASD. First, there is strong evidence that the Mirror Neuron System (MNS is impaired. As stated by this hypothesis, action production and action understanding are intimately related. Both these functions rely on predictive models of the sensory consequences of actions and depend on connectivity between the parietal and pre-motor areas. Secondly, action prediction is accomplished through a system that includes a loop from the posterior parietal cortex through the cerebellum and back to the premotor and motor areas of the brain. Impairment of this loop is probably also part of the explanation of the prediction problems in children with ASD. Both the cortico-cerebellar loop and the MNS rely on distant neural connections. There are multiple evidence that such connections are weak in children with autism.

  8. Precision Medicine Intelligence - evidence scoring evaluating the clinical actionability of BRAF V600E in multiple non-melanoma solid tumors.

    Science.gov (United States)

    Crescenzo, A

    2016-07-01

    With the ever-increasing growth of next-generation sequencing literature, how can researchers and clinicians assess clinical actionability and utility and objectively assign confidence to gene variant-phenotype associations? This article presents an informatics solution for clinical interpretation of patient-derived genomic and molecular data containing manually curated scientific evidence supporting gene variant-disease and -drug response phenotypes in somatic cancers. An algorithm for direct evidence scoring will be used to demonstrate the diverse utility of BRAF V600E in treating many common cancers.

  9. Expressive timing facilitates the neural processing of phrase boundaries in music: evidence from event-related potentials.

    Directory of Open Access Journals (Sweden)

    Eva Istók

    Full Text Available The organization of sound into meaningful units is fundamental to the processing of auditory information such as speech and music. In expressive music performance, structural units or phrases may become particularly distinguishable through subtle timing variations highlighting musical phrase boundaries. As such, expressive timing may support the successful parsing of otherwise continuous musical material. By means of the event-related potential technique (ERP, we investigated whether expressive timing modulates the neural processing of musical phrases. Musicians and laymen listened to short atonal scale-like melodies that were presented either isochronously (deadpan or with expressive timing cues emphasizing the melodies' two-phrase structure. Melodies were presented in an active and a passive condition. Expressive timing facilitated the processing of phrase boundaries as indicated by decreased N2b amplitude and enhanced P3a amplitude for target phrase boundaries and larger P2 amplitude for non-target boundaries. When timing cues were lacking, task demands increased especially for laymen as reflected by reduced P3a amplitude. In line, the N2b occurred earlier for musicians in both conditions indicating general faster target detection compared to laymen. Importantly, the elicitation of a P3a-like response to phrase boundaries marked by a pitch leap during passive exposure suggests that expressive timing information is automatically encoded and may lead to an involuntary allocation of attention towards significant events within a melody. We conclude that subtle timing variations in music performance prepare the listener for musical key events by directing and guiding attention towards their occurrences. That is, expressive timing facilitates the structuring and parsing of continuous musical material even when the auditory input is unattended.

  10. Expressive timing facilitates the neural processing of phrase boundaries in music: evidence from event-related potentials.

    Science.gov (United States)

    Istók, Eva; Friberg, Anders; Huotilainen, Minna; Tervaniemi, Mari

    2013-01-01

    The organization of sound into meaningful units is fundamental to the processing of auditory information such as speech and music. In expressive music performance, structural units or phrases may become particularly distinguishable through subtle timing variations highlighting musical phrase boundaries. As such, expressive timing may support the successful parsing of otherwise continuous musical material. By means of the event-related potential technique (ERP), we investigated whether expressive timing modulates the neural processing of musical phrases. Musicians and laymen listened to short atonal scale-like melodies that were presented either isochronously (deadpan) or with expressive timing cues emphasizing the melodies' two-phrase structure. Melodies were presented in an active and a passive condition. Expressive timing facilitated the processing of phrase boundaries as indicated by decreased N2b amplitude and enhanced P3a amplitude for target phrase boundaries and larger P2 amplitude for non-target boundaries. When timing cues were lacking, task demands increased especially for laymen as reflected by reduced P3a amplitude. In line, the N2b occurred earlier for musicians in both conditions indicating general faster target detection compared to laymen. Importantly, the elicitation of a P3a-like response to phrase boundaries marked by a pitch leap during passive exposure suggests that expressive timing information is automatically encoded and may lead to an involuntary allocation of attention towards significant events within a melody. We conclude that subtle timing variations in music performance prepare the listener for musical key events by directing and guiding attention towards their occurrences. That is, expressive timing facilitates the structuring and parsing of continuous musical material even when the auditory input is unattended.

  11. Neural evidence for the use of digit-image mnemonic in a superior memorist: An fMRI study

    Directory of Open Access Journals (Sweden)

    Li-Jun eYin

    2015-03-01

    Full Text Available Some superior memorists demonstrated exceptional memory for reciting a large body of information. The underlying neural correlates, however, are seldom addressed. C.L., the current holder of Guinness World Record for reciting 67,890 digits in π, participated in this functional magnetic resonance imaging (fMRI study. Thirteen participants without any mnemonics training were included as controls. Our previous studies suggested that C.L. used a digit-image mnemonic in studying and recalling lists of digits, namely associating 2-digit groups of ‘00’ to ‘99’ with images and generating vivid stories out of them (Hu, Ericsson, Yang & Lu, 2009. Thus, 2-digit condition was included, with 1-digit numbers and letters as control conditions. We hypothesized that 2-digit condition in C.L. should elicit the strongest activity in the brain regions which are associated with his mnemonic. Functional MRI results revealed that bilateral frontal poles (FPs, BA10, left superior parietal lobule (SPL, left premotor cortex (PMC, and left dorsolateral prefrontal cortex (DLPFC, were more engaged in both the study and recall phase of 2-digit condition for C.L. relative to controls. Moreover, the left middle/inferior frontal gyri (M/IFG and intraparietal sulci (IPS were less engaged in the study phase of 2-digit condition for C.L. (vs. controls. These results suggested that C.L. relied more on brain regions that are associated with episodic memory other than verbal rehearsal while he used his mnemonic strategies. This study supported theoretical accounts of restructured cognitive mechanisms for the acquisition of superior memory performance.

  12. Neural Consequences of Increasing Body Weight: Evidence from Somatosensory Evoked Potentials and the Frequency-Specificity of Brain Oscillations

    Science.gov (United States)

    Lhomond, Olivia; Teasdale, Normand; Simoneau, Martin; Mouchnino, Laurence

    2016-01-01

    Previous studies on the control of human balance suggested that increased pressure under the feet, leading to reduced plantar sole mechanoreceptors sensitivity, increases body sway. Although this suggestion is attracting, it is unclear whether increased plantar sole pressure simply reduces the transmission of plantar sole afferent to the cortex or also alters the sensorimotor integrative mechanisms. Here we used electrical stimulation applied under the sole of the foot to probe the sensorimotor mechanisms processing foot mechanoreceptors. Balance control of healthy individuals was assessed either when wearing a loaded vest or in normal-weight condition. In the Loaded condition, we observed decreased cortical activity over the primary somatosensory cortex (SI) for both an early P50-N90 somatosensory evoked potential (SEP) and for oscillatory brain activity within the gamma band (30–80 Hz). These reductions were interpreted as a disrupted early sensory transmission (i.e., decreased early SEP) leading to a decreased perception of plantar sole sensory information (i.e., decreased gamma band power). These early sensory mechanisms for the Loaded condition were associated with an increase in the late P170-N210 SEP and oscillatory brain activity within the beta band (19–24 Hz). These neural signatures involved areas which are engaged in sensorimotor integrative processes (secondary somatosensory cortex (SII) and right temporoparietal junction). Altered early and late sensory processes may result from the increase pressure on the mechanoreceptors of the foot sole and not from postural instability per se. Indeed, postural instability with normal weight condition did not lead to SEP changes. PMID:27445758

  13. Meditation experience predicts less negative appraisal of pain: electrophysiological evidence for the involvement of anticipatory neural responses.

    Science.gov (United States)

    Brown, Christopher A; Jones, Anthony K P

    2010-09-01

    The aim of mindfulness meditation is to develop present-focused, non-judgmental, attention. Therefore, experience in meditation should be associated with less anticipation and negative appraisal of pain. In this study we compared a group of individuals with meditation experience to a control group to test whether any differences in the affective appraisal of pain could be explained by lower anticipatory neural processing. Anticipatory and pain-evoked ERPs and reported pain unpleasantness were recorded in response to laser stimuli of matched subjective intensity between the two groups. ERP data were analysed after source estimation with LORETA. No group effects were found on the laser energies used to induce pain. More experienced meditators perceived the pain as less unpleasant relative to controls, with meditation experience correlating inversely with unpleasantness ratings. ERP source data for anticipation showed that in meditators, lower activity in midcingulate cortex relative to controls was related to the lower unpleasantness ratings, and was predicted by lifetime meditation experience. Meditators also reversed the normal positive correlation between medial prefrontal cortical activity and pain unpleasantness during anticipation. Meditation was also associated with lower activity in S2 and insula during the pain-evoked response, although the experiment could not disambiguate this activity from the preceding anticipation response. Our data is consistent with the hypothesis that meditation reduces the anticipation and negative appraisal of pain, but effects on pain-evoked activity are less clear and may originate from preceding anticipatory activity. Further work is required to directly test the causal relationship between meditation, pain anticipation, and pain experience.

  14. The decision to engage cognitive control is driven by expected reward-value: neural and behavioral evidence.

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    Matthew L Dixon

    Full Text Available Cognitive control is a fundamental skill reflecting the active use of task-rules to guide behavior and suppress inappropriate automatic responses. Prior work has traditionally used paradigms in which subjects are told when to engage cognitive control. Thus, surprisingly little is known about the factors that influence individuals' initial decision of whether or not to act in a reflective, rule-based manner. To examine this, we took three classic cognitive control tasks (Stroop, Wisconsin Card Sorting Task, Go/No-Go task and created novel 'free-choice' versions in which human subjects were free to select an automatic, pre-potent action, or an action requiring rule-based cognitive control, and earned varying amounts of money based on their choices. Our findings demonstrated that subjects' decision to engage cognitive control was driven by an explicit representation of monetary rewards expected to be obtained from rule-use. Subjects rarely engaged cognitive control when the expected outcome was of equal or lesser value as compared to the value of the automatic response, but frequently engaged cognitive control when it was expected to yield a larger monetary outcome. Additionally, we exploited fMRI-adaptation to show that the lateral prefrontal cortex (LPFC represents associations between rules and expected reward outcomes. Together, these findings suggest that individuals are more likely to act in a reflective, rule-based manner when they expect that it will result in a desired outcome. Thus, choosing to exert cognitive control is not simply a matter of reason and willpower, but rather, conforms to standard mechanisms of value-based decision making. Finally, in contrast to current models of LPFC function, our results suggest that the LPFC plays a direct role in representing motivational incentives.

  15. A new framework for cortico-striatal plasticity: behavioural theory meets in vitro data at the reinforcement-action interface

    OpenAIRE

    Gurney, Kevin; Humphries, Mark D.; Redgrave, Peter

    2015-01-01

    Operant learning requires that reinforcement signals interact with action representations at a suitable neural interface. Much evidence suggests that this occurs when phasic dopamine, acting as a reinforcement prediction error, gates plasticity at cortico-striatal synapses, and thereby changes the future likelihood of selecting the action(s) coded by striatal neurons. But this hypothesis faces serious challenges. First, cortico-striatal plasticity is inexplicably complex, depending on spike t...

  16. Feeling safe in the plane: neural mechanisms underlying superior action control in airplane pilot trainees – a combined EEG/MRS study

    Science.gov (United States)

    Dharmadhikari, Shalmali; Chmielewski, Witold; Glaubitz, Benjamin; Schmidt-Wilcke, Tobias; Edden, Richard; Dydak, Ulrike; Beste, Christian

    2015-01-01

    In day-to-day life, we need to apply strategies to cascade different actions for efficient unfolding of behaviour. While deficits in action cascading are examined extensively, almost nothing is known about the neuronal mechanisms mediating superior performance above the normal level. To examine this question, we investigate action control in airplane pilot trainees. We use a stop-change paradigm that is able to estimate the efficiency of action cascading on the basis of mathematical constraints. Behavioural and EEG data is analyzed along these constraints and integrated with neurochemical data obtained using Magnetic Resonance Spectroscopy (MRS) from the striatal gamma-aminobutyric acid (GABA) -ergic system. We show that high performance in action cascading, as exemplified in airplane pilot trainees, can be driven by intensified attentional processes, circumventing response selection processes. The results indicate that the efficiency of action cascading and hence the speed of responding as well as attentional gating functions are modulated by striatal GABA and Glutamate + Glutamine concentrations. In superior performance in action cascading similar increases in the concentrations of GABA and Glutamate + Glutamine lead to stronger neurophysiological and behavioural effects as compared to subjects with normal performance in action cascading. PMID:24753040

  17. Neural control of lengthening contractions.

    Science.gov (United States)

    Duchateau, Jacques; Enoka, Roger M

    2016-01-01

    A number of studies over the last few decades have established that the control strategy employed by the nervous system during lengthening (eccentric) differs from those used during shortening (concentric) and isometric contractions. The purpose of this review is to summarize current knowledge on the neural control of lengthening contractions. After a brief discussion of methodological issues that can confound the comparison between lengthening and shortening actions, the review provides evidence that untrained individuals are usually unable to fully activate their muscles during a maximal lengthening contraction and that motor unit activity during submaximal lengthening actions differs from that during shortening actions. Contrary to common knowledge, however, more recent studies have found that the recruitment order of motor units is similar during submaximal shortening and lengthening contractions, but that discharge rate is systematically lower during lengthening actions. Subsequently, the review examines the mechanisms responsible for the specific control of maximal and submaximal lengthening contractions as reported by recent studies on the modulation of cortical and spinal excitability. As similar modulation has been observed regardless of contraction intensity, it appears that spinal and corticospinal excitability are reduced during lengthening compared with shortening and isometric contractions. Nonetheless, the modulation observed during lengthening contractions is mainly attributable to inhibition at the spinal level.

  18. Comparing the processing of music and language meaning using EEG and FMRI provides evidence for similar and distinct neural representations.

    Directory of Open Access Journals (Sweden)

    Nikolaus Steinbeis

    Full Text Available Recent demonstrations that music is capable of conveying semantically meaningful information has raised several questions as to what the underlying mechanisms of establishing meaning in music are, and if the meaning of music is represented in comparable fashion to language meaning. This paper presents evidence showing that expressed affect is a primary pathway to music meaning and that meaning in music is represented in a very similar fashion to language meaning. In two experiments using EEG and fMRI, it was shown that single chords varying in harmonic roughness (consonance/dissonance and thus perceived affect could prime the processing of subsequently presented affective target words, as indicated by an increased N400 and activation of the right middle temporal gyrus (MTG. Most importantly, however, when primed by affective words, single chords incongruous to the preceding affect also elicited an N400 and activated the right posterior STS, an area implicated in processing meaning of a variety of signals (e.g. prosody, voices, motion. This provides an important piece of evidence in support of music meaning being represented in a very similar but also distinct fashion to language meaning: Both elicit an N400, but activate different portions of the right temporal lobe.

  19. Comparing the processing of music and language meaning using EEG and FMRI provides evidence for similar and distinct neural representations.

    Science.gov (United States)

    Steinbeis, Nikolaus; Koelsch, Stefan

    2008-05-21

    Recent demonstrations that music is capable of conveying semantically meaningful information has raised several questions as to what the underlying mechanisms of establishing meaning in music are, and if the meaning of music is represented in comparable fashion to language meaning. This paper presents evidence showing that expressed affect is a primary pathway to music meaning and that meaning in music is represented in a very similar fashion to language meaning. In two experiments using EEG and fMRI, it was shown that single chords varying in harmonic roughness (consonance/dissonance) and thus perceived affect could prime the processing of subsequently presented affective target words, as indicated by an increased N400 and activation of the right middle temporal gyrus (MTG). Most importantly, however, when primed by affective words, single chords incongruous to the preceding affect also elicited an N400 and activated the right posterior STS, an area implicated in processing meaning of a variety of signals (e.g. prosody, voices, motion). This provides an important piece of evidence in support of music meaning being represented in a very similar but also distinct fashion to language meaning: Both elicit an N400, but activate different portions of the right temporal lobe.

  20. Neural correlates of sensory prediction errors in monkeys: evidence for internal models of voluntary self-motion in the cerebellum.

    Science.gov (United States)

    Cullen, Kathleen E; Brooks, Jessica X

    2015-02-01

    During self-motion, the vestibular system makes essential contributions to postural stability and self-motion perception. To ensure accurate perception and motor control, it is critical to distinguish between vestibular sensory inputs that are the result of externally applied motion (exafference) and that are the result of our own actions (reafference). Indeed, although the vestibular sensors encode vestibular afference and reafference with equal fidelity, neurons at the first central stage of sensory processing selectively encode vestibular exafference. The mechanism underlying this reafferent suppression compares the brain's motor-based expectation of sensory feedback with the actual sensory consequences of voluntary self-motion, effectively computing the sensory prediction error (i.e., exafference). It is generally thought that sensory prediction errors are computed in the cerebellum, yet it has been challenging to explicitly demonstrate this. We have recently addressed this question and found that deep cerebellar nuclei neurons explicitly encode sensory prediction errors during self-motion. Importantly, in everyday life, sensory prediction errors occur in response to changes in the effector or world (muscle strength, load, etc.), as well as in response to externally applied sensory stimulation. Accordingly, we hypothesize that altering the relationship between motor commands and the actual movement parameters will result in the updating in the cerebellum-based computation of exafference. If our hypothesis is correct, under these conditions, neuronal responses should initially be increased--consistent with a sudden increase in the sensory prediction error. Then, over time, as the internal model is updated, response modulation should decrease in parallel with a reduction in sensory prediction error, until vestibular reafference is again suppressed. The finding that the internal model predicting the sensory consequences of motor commands adapts for new

  1. Predicate structures, gesture, and simultaneity in the representation of action in British Sign Language: evidence from deaf children and adults.

    Science.gov (United States)

    Cormier, Kearsy; Smith, Sandra; Sevcikova, Zed

    2013-01-01

    British Sign Language (BSL) signers use a variety of structures, such as constructed action (CA), depicting constructions (DCs), or lexical verbs, to represent action and other verbal meanings. This study examines the use of these verbal predicate structures and their gestural counterparts, both separately and simultaneously, in narratives by deaf children with various levels of exposure to BSL (ages 5;1 to 7;5) and deaf adult native BSL signers. Results reveal that all groups used the same types of predicative structures, including children with minimal BSL exposure. However, adults used CA, DCs, and/or lexical signs simultaneously more frequently than children. These results suggest that simultaneous use of CA with lexical and depicting predicates is more complex than the use of these predicate structures alone and thus may take deaf children more time to master.

  2. Chlordiazepoxide enhances the anxiogenic action of CGS 8216 in the social interaction test: evidence for benzodiazepine withdrawal?

    Science.gov (United States)

    File, S E; Pellow, S

    1985-07-01

    The benzodiazepine receptor 'inverse agonist' CGS 8216 has a specific anxiogenic action in the social interaction test that cannot be reversed by other compounds acting at the benzodiazepine site: Ro 15-1788, FG 7142 or beta-CCE. We tried to reverse the anxiogenic effect with chlordiazepoxide, which is able to antagonise the anxiogenic effects of several other compounds acting at benzodiazepine or related sites. Chlordiazepoxide given acutely (10-20 mg/kg) was unable to antagonise the anxiogenic action of CGS 8216 (5-10 mg/kg); instead there was a tendency to enhance its effects. The effects of chlordiazepoxide after 5 days pretreatment were then assessed, since chronic treatment is necessary to reverse the anxiogenic actions of Ro 15-1788 and Ro 5-4864. At 5 mg/kg chronically, chlordiazepoxide was unable to antagonise the anxiogenic effect of CGS 8216, and at 20 mg/kg there was a significant enhancement of the effects of CGS 8216 on social interaction without an effect on locomotor activity. These results are discussed in terms of withdrawal from benzodiazepine treatment.

  3. Establishing New Mappings between Familiar Phones: Neural and Behavioral Evidence for Early Automatic Processing of Nonnative Contrasts.

    Science.gov (United States)

    Barrios, Shannon L; Namyst, Anna M; Lau, Ellen F; Feldman, Naomi H; Idsardi, William J

    2016-01-01

    To attain native-like competence, second language (L2) learners must establish mappings between familiar speech sounds and new phoneme categories. For example, Spanish learners of English must learn that [d] and [ð], which are allophones of the same phoneme in Spanish, can distinguish meaning in English (i.e., /deɪ/ "day" and /ðeɪ/ "they"). Because adult listeners are less sensitive to allophonic than phonemic contrasts in their native language (L1), novel target language contrasts between L1 allophones may pose special difficulty for L2 learners. We investigate whether advanced Spanish late-learners of English overcome native language mappings to establish new phonological relations between familiar phones. We report behavioral and magnetoencepholographic (MEG) evidence from two experiments that measured the sensitivity and pre-attentive processing of three listener groups (L1 English, L1 Spanish, and advanced Spanish late-learners of English) to differences between three nonword stimulus pairs ([idi]-[iði], [idi]-[iɾi], and [iði]-[iɾi]) which differ in phones that play a different functional role in Spanish and English. Spanish and English listeners demonstrated greater sensitivity (larger d' scores) for nonword pairs distinguished by phonemic than by allophonic contrasts, mirroring previous findings. Spanish late-learners demonstrated sensitivity (large d' scores and MMN responses) to all three contrasts, suggesting that these L2 learners may have established a novel [d]-[ð] contrast despite the phonological relatedness of these sounds in the L1. Our results suggest that phonological relatedness influences perceived similarity, as evidenced by the results of the native speaker groups, but may not cause persistent difficulty for advanced L2 learners. Instead, L2 learners are able to use cues that are present in their input to establish new mappings between familiar phones.

  4. Differences in "bottom-up" and "top-down" neural activity in current and former cigarette smokers: Evidence for neural substrates which may promote nicotine abstinence through increased cognitive control.

    Science.gov (United States)

    Nestor, Liam; McCabe, Ella; Jones, Jennifer; Clancy, Luke; Garavan, Hugh

    2011-06-15

    Drug-related stimuli, through conditioning, are thought to acquire incentive motivational properties that code possible reward availability and elicit an attentional bias, possibly through increased "bottom-up" neural processing. The processes underlying this attentional bias are considered important in the maintenance of addiction, and crucially, in relapse among substance users attempting to remain abstinent. Equally, impaired "top-down" cognitive control may impair the ability to restrain "bottom-up" pre-potent behaviours, such as drug use, following exposure to drug-related stimuli. Two experiments sought to identify the neural loci of bottom-up/top-down processing during fMRI. Experiment 1 utilised an attentional bias paradigm to examine the behavioural and neural responses to neutral, emotionally evocative and smoking-related cues in control (n=13), ex-smoking (n=10 - abstinent >12months) and smoking (n=13 - mean >6.5years of use) groups. Experiment 2 used a go/no-go paradigm to examine the neural correlates of motor response inhibition and error monitoring in the same sample. The results of Experiment 1 demonstrated that, across conditions, current smokers had significantly less neural activity in cortical but significantly more activity in subcortical areas compared to both controls and ex-smokers. Ex-smokers exhibited more neural activity than both control and smoker groups in prefrontal cortical regions. Similarly, Experiment 2 revealed that smokers had reduced neural activity in prefrontal cortical regions during motor response inhibition compared to controls while ex-smokers demonstrated greater neural activity in prefrontal cortical regions compared to both controls and smokers during error monitoring. The results reveal cortical and subcortical differences between current smokers and controls and a general pattern of increased prefrontal cortical activity in ex-smokers. These findings may suggest that elevated topdown control might be an important

  5. Evidence for the role of DNA strand passage in the mechanism of action of microcin B17 on DNA gyrase.

    Science.gov (United States)

    Pierrat, Olivier A; Maxwell, Anthony

    2005-03-22

    Microcin B17 (MccB17) is a DNA gyrase poison; in previous work, this bacterial toxin was found to slowly and incompletely inhibit the reactions of supercoiling and relaxation of DNA by gyrase and to stabilize the cleavage complex, depending on the presence of ATP and the DNA topology. We now show that the action of MccB17 on the gyrase ATPase reaction and cleavage complex formation requires a linear DNA fragment of more than 150 base pairs. MccB17 is unable to stimulate the ATPase reaction by stabilizing the weak interactions between short linear DNA fragments (70 base pairs or less) and gyrase, in contrast with the quinolone ciprofloxacin. However, MccB17 can affect the ATP-dependent relaxation of DNA by gyrase lacking its DNA-wrapping or ATPase domains. From these findings, we propose a mode of action of MccB17 requiring a DNA molecule long enough to allow the transport of a segment through the DNA gate of the enzyme. Furthermore, we suggest that MccB17 may trap a transient intermediate state of the gyrase reaction present only during DNA strand passage and enzyme turnover. The proteolytic signature of MccB17 from trypsin treatment of the full enzyme requires DNA and ATP and shows a protection of the C-terminal 47-kDa domain of gyrase, indicating the involvement of this domain in the toxin mode of action and consistent with its proposed role in the mechanism of DNA strand passage. We suggest that the binding site of MccB17 is in the C-terminal domain of GyrB.

  6. Neural substrates of individual differences in human fear learning: evidence from concurrent fMRI, fear-potentiated startle, and US-expectancy data

    NARCIS (Netherlands)

    van Well, S.; Visser, R.M.; Scholte, H.S.; Kindt, M.

    2012-01-01

    To provide insight into individual differences in fear learning, we examined the emotional and cognitive expressions of discriminative fear conditioning in direct relation to its neural substrates. Contrary to previous behavioral-neural (fMRI) research on fear learning—in which the emotional

  7. Comparison of Monetary Policy Actions and Central Bank Communication on Tackling Asset Price Bubbles-Evidence from China's Stock Market.

    Science.gov (United States)

    Sun, Ou; Liu, Zhixin

    2016-01-01

    We examine the different effects of monetary policy actions and central bank communication on China's stock market bubbles with a Time-varying Parameter SVAR model. We find that with negative responses of fundamental component and positive responses of bubble component of asset prices, contractionary monetary policy induces the observed stock prices to rise during periods of large bubbles. By contrast, central bank communication acts on the market through expectation guidance and has more significant effects on stock prices in the long run, which implies that central bank communication be used as an effective long-term instrument for the central bank's policymaking.

  8. Functional magnetic resonance imaging reveals the neural substrates of arm transport and grip formation in reach-to-grasp actions in humans.

    Science.gov (United States)

    Cavina-Pratesi, Cristiana; Monaco, Simona; Fattori, Patrizia; Galletti, Claudio; McAdam, Teresa D; Quinlan, Derek J; Goodale, Melvyn A; Culham, Jody C

    2010-08-01

    Picking up a cup requires transporting the arm to the cup (transport component) and preshaping the hand appropriately to grasp the handle (grip component). Here, we used functional magnetic resonance imaging to examine the human neural substrates of the transport component and its relationship with the grip component. Participants were shown three-dimensional objects placed either at a near location, adjacent to the hand, or at a far location, within reach but not adjacent to the hand. Participants performed three tasks at each location as follows: (1) touching the object with the knuckles of the right hand; (2) grasping the object with the right hand; or (3) passively viewing the object. The transport component was manipulated by positioning the object in the far versus the near location. The grip component was manipulated by asking participants to grasp the object versus touching it. For the first time, we have identified the neural substrates of the transport component, which include the superior parieto-occipital cortex and the rostral superior parietal lobule. Consistent with past studies, we found specialization for the grip component in bilateral anterior intraparietal sulcus and left ventral premotor cortex; now, however, we also find activity for the grasp even when no transport is involved. In addition to finding areas specialized for the transport and grip components in parietal cortex, we found an integration of the two components in dorsal premotor cortex and supplementary motor areas, two regions that may be important for the coordination of reach and grasp.

  9. Toxicity induced by Prasiola crispa to fruit fly Drosophila melanogaster and cockroach Nauphoeta cinerea: evidence for bioinsecticide action.

    Science.gov (United States)

    Zemolin, Ana Paula Pegoraro; Cruz, Litiele Cezar; Paula, Mariane Trindade; Pereira, Betina Kappel; Albuquerque, Margelli Pereira; Victoria, Filipe Carvalho; Pereira, Antônio Batista; Posser, Thaís; Franco, Jeferson Luis

    2014-01-01

    The adverse effects of the alga Prasiola crispa extract (PcE) were investigated in a fruit fly (Drosophila melanogaster) and cockroach (Nauphoeta cinerea) model. In flies, toxicity was assessed as mortality and biochemical alterations including acetylcholinesterase (AChE) activity and oxidative stress markers. The cardiotoxic action of PcE was also examined in a model of semi-isolated cockroach heart. The administration of PcE (2 mg/ml) to flies for 24 h resulted in a marked increase in mortality rate (7.6-fold rise compared to control). AChE activity, glutathione (GSH) levels, and hydroperoxide formation remained unchanged. Fly glutathione S-transferase (GST) and catalase (CAT) activity were significantly altered after PcE treatment. Fraction III (ethyl acetate) of PcE was significantly more toxic to flies compared to fractions I (methanol) and II (ethanol). A significant decrease was noted in cockroach semi-isolated heart function. The addition of 5,5'-dithiobis-(2-nitrobenzoic acid (DTNB), an oxidizing agent, concomitant with the extract significantly blocked this effect, suggesting that reduced compounds may be involved in the cardiotoxic action produced by PcE. Our results show for the first time the adverse effects of PcE in two insect models, Drosophila melanogaster and Nauphoetacinerea. The insecticidal properties of PcE may be related to changes in important antioxidant/detoxifying systems, as well as to changes in insect cardiac function.

  10. The African Network for Evidence-to-Action on Disability: A role player in the realisation of the UNCRPD in Africa

    Directory of Open Access Journals (Sweden)

    Rachel Kachaje

    2014-06-01

    Full Text Available This African Journal of Disability supplement focuses on papers presented at the third AfriNEAD Symposium in 2011. In this closing editorial, we want to give an overview of the rationale and major modes of operation of the African Network for Evidence-to-Action on Disability (AfriNEAD with special focus on recommendations made at the 2011 AfriNEAD Symposium. AfriNEAD is guided and informed by the United Nations Convention on the Rights of Persons with Disabilities (UNCRPD for its research themes. The issues that emerged from AfriNEAD 2011 ranged from children and youth with disabilities; education across the lifespan; economic empowerment; the development process in Africa; health, HIV and AIDS and community-based rehabilitation; holistic wellness; to research evidence and utilisation. Disability-related stigma, the value of emancipatory research and the need to recognise a broader scope of valid methodologies were also highlighted.

  11. The human premotor cortex is 'mirror' only for biological actions.

    Science.gov (United States)

    Tai, Yen F; Scherfler, Christoph; Brooks, David J; Sawamoto, Nobukatsu; Castiello, Umberto

    2004-01-20

    Previous work has shown that both human adults and children attend to grasping actions performed by another person but not necessarily to those made by a mechanical device. According to recent neurophysiological data, the monkey premotor cortex contains "mirror" neurons that discharge both when the monkey performs specific manual grasping actions and when it observes another individual performing the same or similar actions. However, when a human model uses tools to perform grasping actions, the mirror neurons are not activated. A similar "mirror" system has been described in humans, but whether or not it is also tuned specifically to biological actions has never been tested. Here we show that when subjects observed manual grasping actions performed by a human model a significant neural response was elicited in the left premotor cortex. This activation was not evident for the observation of grasping actions performed by a robot model commanded by an experimenter. This result indicates for the first time that in humans the mirror system is biologically tuned. This system appears to be the neural substrate for biological preference during action coding.

  12. Evidence that 17alpha-estradiol is biologically active in the uterine tissue: Antiuterotonic and antiuterotrophic action

    Directory of Open Access Journals (Sweden)

    Navarrete Erika

    2005-07-01

    Full Text Available Abstract Background 17alpha-Estradiol has been considered as the hormonally inactive isomer of 17beta-estradiol. Recently, nongenomic (smooth muscle relaxation and genomic (light estrogenic activity effects of 17alpha-estradiol have been reported, but no reports have yet determined its possible antiestrogenic activity. Therefore, this study investigated: the nongenomic action of 17alpha-estradiol on uterine contractile activity and its potential agonist-antagonist activity on uterine growth. Methods Uterine rings from rats were isometrically recorded. Different concentrations (0.2–200 microM of 17alpha-estradiol were tested on spontaneous contraction and equimolarly compared with 17beta-estradiol. To examine the mechanism of 17alpha-estradiol action, its effect was studied in presence of beta2-antagonist (propranolol, antiestrogens (tamoxifen and ICI 182,780 or inhibitors of protein synthesis (cycloheximide and transcription (actinomycin D. Moreover, contractions induced by high potassium (KCl solution or calcium in depolarized tissues by KCl-calcium free solution were exposed to 17alpha-estradiol. Collaterally, we performed an uterotrophic assay in adult ovariectomized rats measuring the uterine wet weight. The administration for three days of 0.3 microM/day/Kg 17beta-estradiol was equimolarly compared with the response produced by 17alpha-estradiol. Antiuterotrophic activity was assayed by administration of 0.3 microM/day/Kg 17beta-estradiol and various doses ratios (1:1, 1:3, 1:5, and 1:100 of 17alpha-estradiol. Results The estradiol isomers elicited an immediate relaxation, concentration-dependent and reversible on spontaneous contraction. 17alpha-Estradiol presented lower potency than 17beta-estradiol although it did not antagonize 17beta-estradiol-induced relaxation. Relaxation to 17alpha-estradiol was not inhibited by propranolol, tamoxifen, ICI 182,780, cycloheximide or actinomycin D. The KCl contractions were also sensitive to 17alpha

  13. Functional responses in the human spinal cord during willed motor actions: evidence for side- and rate-dependent activity.

    Science.gov (United States)

    Maieron, Marta; Iannetti, Gian Domenico; Bodurka, Jerzy; Tracey, Irene; Bandettini, Peter A; Porro, Carlo A

    2007-04-11

    Although the spinal cord is the output station of the central motor system, little is known about the relationships between its functional activity and willed movement parameters in humans. We investigated here blood oxygenation level-dependent functional magnetic resonance imaging (fMRI) signal changes in the cervical spinal cord during a simple finger-to-thumb opposition task in 13 right-handed volunteers, using a dedicated array of 16 receive-only surface coils on a 3 Tesla MRI system. In a first experiment, we found significant fMRI signal increases on both sides of the lower cervical spinal cord while subjects performed the motor task at a comfortable pace (approximately 0.5 Hz) using either hand. Both the spatial extent of movement-related clusters and peak signal increases were significantly higher on the side of the cord ipsilateral to the moving hand than on the contralateral side. Movement-related activity was consistently larger than signal fluctuations during rest. In a second experiment, we recorded spinal cord responses while the same motor sequence was performed using the dominant hand at two different rates (approximately 0.5 or 1 Hz). The intensity but not the spatial extent of the response was larger during higher rates, and it was higher on the ipsilateral side of the cord. Notwithstanding the limited spatial resolving power of the adopted technique, the present results clearly indicate that the finger movement-related fMRI signals recorded from the spinal cord have a neural origin and that as a result of recent technological advances, fMRI can be used to obtain novel and quantitative physiological information on the activity of spinal circuits.

  14. Creation of a Research Community in a K-12 School System Using Action Research and Evidence Based Practice

    Directory of Open Access Journals (Sweden)

    Jean K. Sand

    2009-06-01

    Full Text Available Objective - The purpose of this study was to apply skills developed from an Action Research Training Model (Gordon in the design of two action research projects to ensure that students are ethical users of ideas and information. It was deemed necessary to assess prior knowledge and attitudes of students and teachers in order to identify issues to be addressed. Methods - Both projects employed the use of survey instruments, which presented students with scenarios involving aspects of information use, and asked whether or not the actions in the scenarios were examples of ethical use. The high school survey was administered to 381 students in tenth grade English classes. The elementary survey was administered to 87 students in fifth grade. A more comprehensive survey was administered at the high school level. For each student behavior addressed by the survey, there were two questions: one eliciting the teacher’s perception of how often students engaged in that behavior, and the second how often the teacher had to confront a student about the same behavior. Participation was voluntary, and 36 teachers took the survey. Results - Surveys administered at the high school level showed that most students have a good understanding of the ethical use of information regarding clear instances of plagiarism. Students’ understanding was less clear in two major areas: creating a bibliography that accurately reflects the sources used to create the work, and the level of collaboration or assistance that is appropriate in completing a research assignment. The teacher surveys showed some discrepancy between perception of the frequency of certain types of unethical student behavior and how often teachers challenged students on that behavior. The surveys showed that teachers found plagiarism to be the most prevalent behavior, while obtaining copies of exams and buying papers were the least frequently occurring behaviors. At the elementary level, results indicated

  15. Proprioception contributes to the sense of agency during visual observation of hand movements: evidence from temporal judgments of action

    DEFF Research Database (Denmark)

    Balslev, Daniela; Cole, Jonathan; Miall, R Chris

    2007-01-01

    The ability to recognize visually one's own movement is important for motor control and, through attribution of agency, for social interactions. Agency of actions may be decided by comparisons of visual feedback, efferent signals, and proprioceptive inputs. Because the ability to identify one's own...... visual feedback from passive movements is decreased relative to active movements, or in some cases is even absent, the role of proprioception in self-recognition has been questioned. Proprioception during passive and active movements may, however, differ, and so to address any role for proprioception...... synchronously or asynchronously with a random delay, and reported whether or not they felt they controlled the cursor. Movement accuracy was matched between groups. In the absence of proprioception, I.W. was less able than the control group to discriminate self- from computer-produced cursor movement based...

  16. Structures and dynamics of transnational cooperation networks: evidence based on Local Action Groups in the Veneto Region, Italy

    Directory of Open Access Journals (Sweden)

    Elena Pisani

    2014-12-01

    Full Text Available The paper assesses the structures and dynamics of transnational cooperation projects promoted by Local Action Groups (LAGs in different periods (from LEADER II to LEADER Axis using Social Network Analysis (SNA in a specific case study: the Veneto Region in Italy. The classical indexes of SNA have been critically examined, and the paper also presents innovative indexes that can capture the peculiarity of transnational cooperation: disaggregated densities of the network and transnational centrality of the node. These indexes are useful in order to quantify how transnational a network actually is, and to measure the power-information that each actor (LAG can acquire through its transnational contacts. The methodology can become a tool for Managing Authorities to implement new forms of evaluation of transnational cooperation of LAGs.

  17. An evidence-based, point-of-care tool to guide completion of asthma action plans in practice.

    Science.gov (United States)

    Kouri, Andrew; Boulet, Louis-Philippe; Kaplan, Alan; Gupta, Samir

    2017-05-01

    Asthma action plans (AAPs) reduce healthcare utilisation, improve quality of life and are recommended across guidelines. However, fewer than 25% of patients receive an AAP, partly due to prescribers' inability to complete "yellow zone" instructions (how to intensify therapy for acute loss of control). We sought to review best evidence to develop a practical, evidence-based tool to facilitate yellow zone guidance in adults.We reviewed recent asthma guidelines and adult studies addressing acute loss of asthma control (January 2010 to March 2016). We developed evidence-based rules for yellow zone therapy and operational guidelines to maximise adherence and minimise errors.We reviewed three guidelines and 11 manuscripts (2486 abstracts screened). Recommendations were comparable but some areas lacked guidance. For 15/43 asthma regimens, the commonly recommended four- to five-fold yellow zone inhaled corticosteroid dose increase was problematic due to regulatory dose limits. We identified evidence-based alternatives for 8/15 regimens. Operational guidance included increasing to a maximum of four inhalations while maintaining baseline inhaler frequency and device in the yellow zone.We developed a practical implementation tool to facilitate AAP delivery at the point of care, addressing existing gaps and uncertainties. Our tool should be implemented as part of a multifaceted approach to augment AAP usage. Copyright ©ERS 2017.

  18. The role of the epidermis in the control of scarring: evidence for mechanism of action for silicone gel.

    Science.gov (United States)

    Tandara, Andrea A; Mustoe, Thomas A

    2008-10-01

    Hypertrophic scars can be reduced by the application of silicone dressing; however, the detailed mechanism of silicone action is still unknown. It is known that silicone gel sheets cause a hydration of the epidermal layer of the skin. An in vitro co-culture experiment has shown that hydration of keratinocytes has a suppressive effect on the metabolism of the underlying fibroblasts resulting in reduced collagen deposition. We tested the hypothesis that silicone sheeting in vivo has a beneficial effect on scarring by reducing keratinocyte stimulation, with a resulting decrease in dermal thickness, hence scar hypertrophy. Silicone adhesive gel sheets were applied to scars in our rabbit ear model of hypertrophic scarring 14 days postwounding for a total of 16 days. Scarring was measured in this model by the scar elevation index (SEI), a ratio of the area of newly formed dermis to the area of the dermis of unwounded skin, and the epidermal thickness index (ETI), a ratio of the averaged epidermal height of the scar to the epidermal thickness of normal epidermis. Specific staining [anti-PCNA (proliferating cell nuclear antigen) and Masson trichrome] was performed to reveal differences in scar morphology. SEIs were significantly reduced after silicone gel sheet application versus untreated scars corresponding to a 70% reduction in scar hypertrophy. Total occlusion reduced scar hypertrophy by 80% compared to semi-occlusion. ETIs of untreated scars were increased by more than 100% compared to uninjured skin. Silicone gel treatment significantly reduced epidermal thickness by more than 30%. Our findings demonstrate that 2 weeks of silicone gel application at a very early onset of scarring reduces dermal and epidermal thickness which appears to be due to a reduction in keratinocyte stimulation. Oxygen can be ruled out as a mechanism of action of silicone occlusive treatment. Hydration of the keratinocytes seems to be the key stimulus.

  19. Evidence of the protein content of bovine and human dental pulps by the action of endodontic irrigation solutions through electrophoretic patterns

    Directory of Open Access Journals (Sweden)

    María E López

    2013-01-01

    Full Text Available Background: Sodium dodecyl sulfate polyacrylamide gel electrophoresis let to show the protein content of different tissues. Dental pulp contains connective tissue which is removed during the endodontic treatment. Many studies consider bovine rather than human pulp tissue because of its size. Aim: To evidence the protein content of bovine and human dental pulps and the action of endodontic irrigation solutions through electrophoretic patterns. Materials and Methods: Extracts of human and bovine dental pulps were prepared. Sodium hypochlorite, calcium hydroxide, chlorhexidine and ethylenediamine tetraacetic acid were used as irrigating solutions. Results: Bovine and human pulps have a small difference in two bands of proteins present between 74 kDa and 80 kDa. The denaturizing capacity of sodium hypochlorite and the washing action of calcium hydroxide and chlorhexidine were evidenced. Ethylenediamine tetraacetic acid solution was shown to contain proteins continuously during the endodontic root canal washing. Conclusions: Differences in pulp tissues and the action of irrigating solutions on their protein content would help on the understanding of the biological process of the endodontic treatment.

  20. Neural overlap in processing music and speech.

    Science.gov (United States)

    Peretz, Isabelle; Vuvan, Dominique; Lagrois, Marie-Élaine; Armony, Jorge L

    2015-03-19

    Neural overlap in processing music and speech, as measured by the co-activation of brain regions in neuroimaging studies, may suggest that parts of the neural circuitries established for language may have been recycled during evolution for musicality, or vice versa that musicality served as a springboard for language emergence. Such a perspective has important implications for several topics of general interest besides evolutionary origins. For instance, neural overlap is an important premise for the possibility of music training to influence language acquisition and literacy. However, neural overlap in processing music and speech does not entail sharing neural circuitries. Neural separability between music and speech may occur in overlapping brain regions. In this paper, we review the evidence and outline the issues faced in interpreting such neural data, and argue that converging evidence from several methodologies is needed before neural overlap is taken as evidence of sharing.

  1. Neural overlap in processing music and speech

    Science.gov (United States)

    Peretz, Isabelle; Vuvan, Dominique; Lagrois, Marie-Élaine; Armony, Jorge L.

    2015-01-01

    Neural overlap in processing music and speech, as measured by the co-activation of brain regions in neuroimaging studies, may suggest that parts of the neural circuitries established for language may have been recycled during evolution for musicality, or vice versa that musicality served as a springboard for language emergence. Such a perspective has important implications for several topics of general interest besides evolutionary origins. For instance, neural overlap is an important premise for the possibility of music training to influence language acquisition and literacy. However, neural overlap in processing music and speech does not entail sharing neural circuitries. Neural separability between music and speech may occur in overlapping brain regions. In this paper, we review the evidence and outline the issues faced in interpreting such neural data, and argue that converging evidence from several methodologies is needed before neural overlap is taken as evidence of sharing. PMID:25646513

  2. Fault diagnosis of DCT electronic control system based on neural network and evidence theory%基于神经网络和证据理论的DCT电控系统故障诊断

    Institute of Scientific and Technical Information of China (English)

    孔慧芳; 段锐; 鲍伟

    2015-01-01

    为了提高双离合器自动变速器(dual‐clutch transmission ,DCT )电控系统故障诊断精度,文章提出了一种基于神经网络和证据理论的DCT电控系统故障诊断方法。该方法首先分别用BP神经网络和RBF神经网络对DC T电控系统进行故障诊断,然后利用D‐S证据理论将两者的诊断结果进行决策融合,得出最终的诊断结果。仿真结果表明,该方法能够有效提高DC T电控系统故障诊断的精度。%In order to improve the fault diagnosis accuracy of dual‐clutch transmission(DCT ) electronic control system ,a fault diagnosis scheme based on neural network and D‐S evidence theory is devel‐oped .Both the fault diagnosis based on BP neural network and based on RBF neural network of DCT electronic control system are studied .Then the D‐S evidence theory is applied to fusing the diagnosis results of BP neural network and RBF neural network .The simulation results are presented to demon‐strate the validity and effectiveness of the fault diagnosis scheme .

  3. Electrophysiological evidence for the action of a center-surround mechanism on semantic processing in the left hemisphere

    Directory of Open Access Journals (Sweden)

    Diana eDeacon

    2013-12-01

    Full Text Available Physiological evidence was sought for a center-surround attentional mechanism (CSM, which has been proposed to assist in the retrieval of weakly activated items from semantic memory. The CSM operates by facilitating strongly related items in the center of the weakly activated area of semantic memory, and inhibiting less strongly related items in its surround. In this study weak activation was created by having subjects acquire the meanings of new words to a recall criterion of only 50%. Subjects who attained this approximate criterion level of performance were subsequently included in a semantic priming task, during which ERPs were recorded. Primes were newly learned rare words, and targets were either synonyms, nonsynonymously related words, or unrelated words. All stimuli were presented to the RVF/LH (right visual field/left hemisphere or the LVF/RH (left visual field/right hemisphere. Under RVF/LH stimulation the newly learned word primes produced facilitation on N400 for synonym targets, and inhibition for related targets. No differences were observed under LVF/RH stimulation. The LH thus, supports a CSM, whereby a synonym in the center of attention focused on the newly learned word is facilitated, whereas a related word in the surround is inhibited. The data are consistent with the view of this laboratory that semantic memory is subserved by a spreading activation system in the LH. Also consistent with our view, there was no evidence of spreading activation in the RH. The findings are discussed in the context of additional recent theories of semantic memory. Finally, the adult right hemisphere may require more learning than the LH in order to demonstrate evidence of meaning acquisition.

  4. Evidence for simvastatin anti-inflammatory actions based on quantitative analyses of NETosis and other inflammation/oxidation markers

    Directory of Open Access Journals (Sweden)

    Walid M. Al-Ghoul

    2014-01-01

    Full Text Available Simvastatin (SMV has been shown to exhibit promising anti-inflammatory properties alongside its classic cholesterol lowering action. We tested these emerging effects in a major thermal injury mouse model (3rd degree scald, ~20% TBSA with previously documented, inflammation-mediated intestinal defects. Neutrophil extracellular traps (NETs inflammation measurement methods were used alongside classic gut mucosa inflammation and leakiness measurements with exogenous melatonin treatment as a positive control. Our hypothesis is that simvastatin has protective therapeutic effects against early postburn gut mucosa inflammation and leakiness. To test this hypothesis, we compared untreated thermal injury (TI adult male mice with TI littermates treated with simvastatin (0.2 mg/kg i.p., TI+SMV immediately following burn injury and two hours before being sacrificed the day after; melatonin-treated (Mel (1.86 mg/kg i.p., TI+Mel mice were compared as a positive control. Mice were assessed for the following: (1 tissue oxidation and neutrophil infiltration in terminal ileum mucosa using classic carbonyl, Gr-1, and myeloperoxidase immunohistochemical or biochemical assays, (2 NETosis in terminal ileum and colon mucosa homogenates and peritoneal and fluid blood samples utilizing flow cytometric analyses of the surrogate NETosis biomarkers, picogreen and Gr-1, and (3 transepithelial gut leakiness as measured in terminal ileum and colon with FITC-dextran and transepithelial electrical resistance (TEER. Our results reveal that simvastatin and melatonin exhibit consistently comparable therapeutic protective effects against the following: (1 gut mucosa oxidative stress as revealed in the terminal ileum by markers of protein carbonylation as well as myeloperoxidase (MPO and Gr-1 infiltration, (2 NETosis as revealed in the gut milieu, peritoneal lavage and plasma utilizing picogreen and Gr-1 flow cytometry and microscopy, and (3 transepithelial gut leakiness as assessed

  5. mGluR2/3 mechanisms in primate dorsolateral prefrontal cortex: Evidence for both presynaptic and postsynaptic actions

    Science.gov (United States)

    Jin, Lu E.; Wang, Min; Yang, Sheng-Tao; Yang, Yang; Galvin, Veronica C.; Lightbourne, Taber C.; Ottenheimer, David; Zhong, Qiaonan; Stein, Josh; Raja, Anusha; Paspalas, Constantinos D.; Arnsten, Amy F.T.

    2016-01-01

    Cognitive deficits in psychiatric and age-related disorders generally involve dysfunction of the dorsolateral prefrontal cortex (dlPFC), but there are few treatments for these debilitating symptoms. Group II metabotropic glutamate receptors (mGluR2/3), which couple to Gi/Go, have been a focus of therapeutics based on rodent research, where mGluR2/3 have been shown to reduce axonal glutamate release and increase glial glutamate uptake. However, this strategy has had mixed results in patients, and understanding mGluR2/3 mechanisms in primates will help guide therapeutic interventions. The current study examined mGluR2/3 localization and actions in the primate dlPFC layer III circuits underlying working memory, where the persistent firing of “Delay cells” is mediated by NMDA receptors and weakened by cAMP-PKA-potassium channel signaling in dendritic spines. Immunoelectron microscopy identified postsynaptic mGluR2/3 in the spines, in addition to the traditional presynaptic and astrocytic locations. In vivo iontophoretic application of the mGluR2/3 agonists (2R, 4R)-APDC or LY379268 onto dlPFC Delay cells produced an inverted-U effect on working memory representation, with enhanced neuronal firing following low doses of mGluR2/3 agonists. The enhancing effects were reversed by an mGluR2/3 antagonist or by activating cAMP signaling, consistent with mGluR2/3 inhibiting postsynaptic cAMP signaling in spines. Systemic administration of these agonists to monkeys performing a working memory task also produced an inverted-U dose-response, where low doses improved performance but higher doses, similar to clinical trials, had mixed effects. Our data suggest that low dose mGluR2/3 stimulation may have therapeutic effects through unexpected postsynaptic actions in dlPFC, strengthening synaptic connections and improving cognitive function. PMID:27502475

  6. Evidence for Helical Magnetic fields in Kiloparsec-Scale AGN Jets and the Action of a Cosmic Battery

    Science.gov (United States)

    Gabuzda, D. C.; Christodoulou, D. M.; Contopulos, I.; Kazanas, D.

    2012-01-01

    A search for transverse kiloparsec-scale gradients in Faraday rotation-measure (RM) maps of extragalactic radio sources in the literature has yielded 6 AGNs displaying continuous, monotonic RM gradients across their jets, oriented roughly orthogonal to the local jet direction. The most natural interpretation of such transverse RM gradients is that they are caused by the systematic change in the line-of-sight components of helical magnetic fields associated with these jets. All the identified transverse RM gradients increase in the counterclockwise (CCW) direction on the sky relative to the centers of these AGNs. Taken together with the results of Contopoulos et al. who found evidence for a predominance of clockwise (CW) transverse RM gradients across parsec-scale (VLBI) jets, this provides new evidence for preferred orientations of RM gradients due to helical jet magnetic fields, with a reversal from CW in the inner jets to CCW farther from the centers of activity. This can be explained by the "Poynting-Robertson cosmic-battery" mechanism, which can generate helical magnetic fields with a. characteristic "twist," which are expelled with the jet outflows. If the Poynting-Robertson battery mechanism is not operating, an alternative mechanism must be identified, which is able to explain the 'predominance of CW /CCW RM gradients on parsec/kiloparsec scales.

  7. A role for the precuneus in thought–action fusion: Evidence from participants with significant obsessive–compulsive symptoms

    Directory of Open Access Journals (Sweden)

    Rhiannon Jones

    2014-01-01

    Full Text Available Likelihood thought–action fusion (TAF-L refers to a cognitive bias in which individuals believe that the mere thought of a negative event increases its likelihood of occurring in reality. TAF-L is most commonly associated with obsessive–compulsive disorder (OCD but is also present in depression, generalized anxiety disorder and psychosis. We induced TAF-L in individuals with high (High-OC, N = 23 and low (Low-OC, N = 24 levels of OC traits, and used low resolution electromagnetic tomography (LORETA to localise the accompanying electrical brain activity patterns. The results showed greater TAF-L in the High-OC than in the Low-OC group (p < .005, which was accompanied by significantly greater upper beta frequency (19–30 Hz activity in the precuneus (p < .05. Further, the precuneus activity was positively correlated with self-reported magnitude of TAF-L (p < .01, suggesting a specific role of this region in this cognitive bias. Results are discussed with reference to self-referential processing and the default-mode network.

  8. Modelling the control of interceptive actions

    National Research Council Canada - National Science Library

    P. J. Beek; J. C. Dessing; C. E. Peper; D. Bullock

    2003-01-01

    .... We call these short–route models as they do not address how perception–action patterns might be constrained by the dynamical properties of the sensory, neural and musculoskeletal subsystems of the human action system...

  9. Lithium promotes neural precursor cell proliferation: evidence for the involvement of the non-canonical GSK-3β-NF-AT signaling

    Directory of Open Access Journals (Sweden)

    Qu Zhaoxia

    2011-05-01

    Full Text Available Abstract Lithium, a drug that has long been used to treat bipolar disorder and some other human pathogenesis, has recently been shown to stimulate neural precursor growth. However, the involved mechanism is not clear. Here, we show that lithium induces proliferation but not survival of neural precursor cells. Mechanistic studies suggest that the effect of lithium mainly involved activation of the transcription factor NF-AT and specific induction of a subset of proliferation-related genes. While NF-AT inactivation by specific inhibition of its upstream activator calcineurin antagonized the effect of lithium on the proliferation of neural precursor cells, specific inhibition of the NF-AT inhibitor GSK-3β, similar to lithium treatment, promoted neural precursor cell proliferation. One important function of lithium appeared to increase inhibitory phosphorylation of GSK-3β, leading to GSK-3β suppression and subsequent NF-AT activation. Moreover, lithium-induced proliferation of neural precursor cells was independent of its role in inositol depletion. These findings not only provide mechanistic insights into the clinical effects of lithium, but also suggest an alternative therapeutic strategy for bipolar disorder and other neural diseases by targeting the non-canonical GSK-3β-NF-AT signaling.

  10. Somatosensory-motor adaptation of orofacial actions in posterior parietal and ventral premotor cortices.

    Directory of Open Access Journals (Sweden)

    Krystyna Grabski

    Full Text Available Recent studies have provided evidence for sensory-motor adaptive changes and action goal coding of visually guided manual action in premotor and posterior parietal cortices. To extend these results to orofacial actions, devoid of auditory and visual feedback, we used a repetition suppression paradigm while measuring neural activity with functional magnetic resonance imaging during repeated intransitive and silent lip, jaw and tongue movements. In the motor domain, this paradigm refers to decreased activity in specific neural populations due to repeated motor acts and has been proposed to reflect sensory-motor adaptation. Orofacial movements activated a set of largely overlapping, common brain areas forming a core neural network classically involved in orofacial motor control. Crucially, suppressed neural responses during repeated orofacial actions were specifically observed in the left ventral premotor cortex, the intraparietal sulcus, the inferior parietal lobule and the superior parietal lobule. Since no visual and auditory feedback were provided during orofacial actions, these results suggest somatosensory-motor adaptive control of intransitive and silent orofacial actions in these premotor and parietal regions.

  11. Managing and Mitigating the Health Risks of Climate Change: Calling for Evidence-Informed Policy and Action

    Science.gov (United States)

    Tong, Shilu; Confalonieri, Ulisses; Ebi, Kristie; Olsen, Jorn

    2016-01-01

    Summary: Climate change affects many natural and social systems and processes that are essential for life. It disrupts the Earth’s life-support systems that underpin the world’s capacity to supply adequate food and fresh water, and it disturbs the eco-physical buffering against natural disasters. Epidemiologists need to develop and improve research and monitoring programs to better understand the scale and immediacy of the threat of climate change to human health and to act within a much larger and more comprehensive framework. To address one of the greatest environmental issues of our lifetime, the scientific and policy-making communities should work together to formulate evidence-informed public policy to mitigate greenhouse gas emissions and adapt to its inevitable impacts in this generation and, more importantly, in future generations to come. PMID:27689449

  12. From science to action: Principles for undertaking environmental research that enables knowledge exchange and evidence-based decision-making.

    Science.gov (United States)

    Cvitanovic, C; McDonald, J; Hobday, A J

    2016-12-01

    Effective conservation requires knowledge exchange among scientists and decision-makers to enable learning and support evidence-based decision-making. Efforts to improve knowledge exchange have been hindered by a paucity of empirically-grounded guidance to help scientists and practitioners design and implement research programs that actively facilitate knowledge exchange. To address this, we evaluated the Ningaloo Research Program (NRP), which was designed to generate new scientific knowledge to support evidence-based decisions about the management of the Ningaloo Marine Park in north-western Australia. Specifically, we evaluated (1) outcomes of the NRP, including the extent to which new knowledge informed management decisions; (2) the barriers that prevented knowledge exchange among scientists and managers; (3) the key requirements for improving knowledge exchange processes in the future; and (4) the core capacities that are required to support knowledge exchange processes. While the NRP generated expansive and multidisciplinary science outputs directly relevant to the management of the Ningaloo Marine Park, decision-makers are largely unaware of this knowledge and little has been integrated into decision-making processes. A range of barriers prevented efficient and effective knowledge exchange among scientists and decision-makers including cultural differences among the groups, institutional barriers within decision-making agencies, scientific outputs that were not translated for decision-makers and poor alignment between research design and actual knowledge needs. We identify a set of principles to be implemented routinely as part of any applied research program, including; (i) stakeholder mapping prior to the commencement of research programs to identify all stakeholders, (ii) research questions to be co-developed with stakeholders, (iii) implementation of participatory research approaches, (iv) use of a knowledge broker, and (v) tailored knowledge management

  13. Negative symptoms and the failure to represent the expected reward value of actions: behavioral and computational modeling evidence.

    Science.gov (United States)

    Gold, James M; Waltz, James A; Matveeva, Tatyana M; Kasanova, Zuzana; Strauss, Gregory P; Herbener, Ellen S; Collins, Anne G E; Frank, Michael J

    2012-02-01

    Negative symptoms are a core feature of schizophrenia, but their pathogenesis remains unclear. Negative symptoms are defined by the absence of normal function. However, there must be a productive mechanism that leads to this absence. To test a reinforcement learning account suggesting that negative symptoms result from a failure in the representation of the expected value of rewards coupled with preserved loss-avoidance learning. Participants performed a probabilistic reinforcement learning paradigm involving stimulus pairs in which choices resulted in reward or in loss avoidance. Following training, participants indicated their valuation of the stimuli in a transfer test phase. Computational modeling was used to distinguish between alternative accounts of the data. A tertiary care research outpatient clinic. In total, 47 clinically stable patients with a diagnosis of schizophrenia or schizoaffective disorder and 28 healthy volunteers participated in the study. Patients were divided into a high-negative symptom group and a low-negative symptom group. The number of choices leading to reward or loss avoidance, as well as performance in the transfer test phase. Quantitative fits from 3 different models were examined. Patients in the high-negative symptom group demonstrated impaired learning from rewards but intact loss-avoidance learning and failed to distinguish rewarding stimuli from loss-avoiding stimuli in the transfer test phase. Model fits revealed that patients in the high-negative symptom group were better characterized by an "actor-critic" model, learning stimulus-response associations, whereas control subjects and patients in the low-negative symptom group incorporated expected value of their actions ("Q learning") into the selection process. Negative symptoms in schizophrenia are associated with a specific reinforcement learning abnormality: patients with high-negative symptoms do not represent the expected value of rewards when making decisions but learn

  14. Addressing the social and environmental determinants of urban health equity: evidence for action and a research agenda.

    Science.gov (United States)

    Friel, Sharon; Akerman, Marco; Hancock, Trevor; Kumaresan, Jacob; Marmot, Michael; Melin, Thomas; Vlahov, David

    2011-10-01

    Urban living is the new reality for the majority of the world's population. Urban change is taking place in a context of other global challenges--economic globalization, climate change, financial crises, energy and food insecurity, old and emerging armed conflicts, as well as the changing patterns of communicable and noncommunicable diseases. These health and social problems, in countries with different levels of infrastructure and health system preparedness, pose significant development challenges in the 21st century. In all countries, rich and poor, the move to urban living has been both good and bad for population health, and has contributed to the unequal distribution of health both within countries (the urban-rural divide) and within cities (the rich-poor divide). In this series of papers, we demonstrate that urban planning and design and urban social conditions can be good or bad for human health and health equity depending on how they are set up. We argue that climate change mitigation and adaptation need to go hand-in-hand with efforts to achieve health equity through action in the social determinants. And we highlight how different forms of governance can shape agendas, policies, and programs in ways that are inclusive and health-promoting or perpetuate social exclusion, inequitable distribution of resources, and the inequities in health associated with that. While today we can describe many of the features of a healthy and sustainable city, and the governance and planning processes needed to achieve these ends, there is still much to learn, especially with respect to tailoring these concepts and applying them in the cities of lower- and middle-income countries. By outlining an integrated research agenda, we aim to assist researchers, policy makers, service providers, and funding bodies/donors to better support, coordinate, and undertake research that is organized around a conceptual framework that positions health, equity, and sustainability as central

  15. Evidence for a central mode of action for etoricoxib (COX-2 inhibitor) in patients with painful knee osteoarthritis.

    Science.gov (United States)

    Arendt-Nielsen, Lars; Egsgaard, Line Lindhardt; Petersen, Kristian Kjær

    2016-08-01

    The COX-2 inhibitor etoricoxib modulates the peripheral and central nociceptive mechanisms in animals. This interaction has not been studied in patients with pain. This randomized, double-blind, placebo-controlled, 2-way crossover, 4-week treatment study investigated the pain mechanisms modulated by etoricoxib in patients with painful knee osteoarthritis. Patients were randomized to group A (60 mg/d etoricoxib followed by placebo) or B (placebo followed by 60 mg/d etoricoxib). The quantitative, mechanistic pain biomarkers were pressure pain thresholds, temporal summation (TS), and conditioning pain modulation. Clinical readouts were Brief Pain Inventory, WOMAC, painDETECT questionnaire (PD-Q), and time and pain intensity during walking and stair climbing. Etoricoxib as compared with placebo significantly modulated the pressure pain thresholds (P = 0.012, localized sensitization) at the knee and leg (control site) (P = 0.025, spreading sensitization) and TS assessed from the knee (P = 0.038) and leg (P = 0.045). Conditioning pain modulation was not modulated. The Brief Pain Inventory (pain scores), PD-Q, WOMAC, and walking and stair climbing tests were all significantly improved by etoricoxib. Based on a minimum of 30% or 50% pain alleviation (day 0-day 28), responders and nonresponders were defined. The nonresponders showed a significant association between increased facilitation of TS and increased pain alleviation. None of the other parameters predicted the degree of pain alleviation. Generally, a responder to etoricoxib has the most facilitated TS. In conclusion, etoricoxib (1) modulated central pain modulatory mechanisms and (2) improved pain and function in painful osteoarthritis. Stronger facilitation of TS may indicate a better response to etoricoxib, supporting the central mode-of-action of the drug.

  16. The integration of size and weight cues for perception and action: evidence for a weight-size illusion.

    Science.gov (United States)

    Hirsiger, Sarah; Pickett, Kristen; Konczak, Jürgen

    2012-11-01

    Humans routinely estimate the size and weight of objects. Yet, when lifting two objects of equal weight but different size, they often perceive the smaller object as being heavier. This size-weight illusion (SWI) is known to have a lesser effect on motor control of object lifting. How the nervous system combines "weight" and "size" cues with prior experience and whether these cues are differentially integrated for perception and sensorimotor action is still not fully understood. Therefore, we assessed not only whether the experience of size biases weight perception, but also if experience of weight biases the size perception of objects. Further, to investigate differences between perceptual and motor systems for cue-experience integration, participants haptically explored the weight of an object with one hand and then shaped the aperture of their other hand to indicate its perceived size. Results-First, next to a SWI, healthy adults (N = 21) perceived lighter objects as being smaller and heavier objects as being larger, demonstrating a weight-size illusion (WSI). Second, participants were more susceptible to either the SWI or WSI. Third, aperture of the non-exploring hand was scaled to perceived weight and not to physical size. Hand openings were consistently smaller than physical size, with SWI-sensitive participants being significantly more affected than WSI-sensitive subjects. We conclude: first, both size and weight perceptions are biased by prior experience. Weight perception is biased by expectations of size, while size perception is influenced by the expectancy of weight. Second, humans have the tendency to use one cue predominantly for both types of perception. Third, combining perceived weight with expected size influenced hand motor control, while online haptic feedback was largely ignored. Finally, we present a processing model underlying the size-weight cue integration for the perceptual and motor system.

  17. Triadic (ecological, neural, cognitive) niche construction: a scenario of human brain evolution extrapolating tool use and language from the control of reaching actions.

    Science.gov (United States)

    Iriki, Atsushi; Taoka, Miki

    2012-01-12

    Hominin evolution has involved a continuous process of addition of new kinds of cognitive capacity, including those relating to manufacture and use of tools and to the establishment of linguistic faculties. The dramatic expansion of the brain that accompanied additions of new functional areas would have supported such continuous evolution. Extended brain functions would have driven rapid and drastic changes in the hominin ecological niche, which in turn demanded further brain resources to adapt to it. In this way, humans have constructed a novel niche in each of the ecological, cognitive and neural domains, whose interactions accelerated their individual evolution through a process of triadic niche construction. Human higher cognitive activity can therefore be viewed holistically as one component in a terrestrial ecosystem. The brain's functional characteristics seem to play a key role in this triadic interaction. We advance a speculative argument about the origins of its neurobiological mechanisms, as an extension (with wider scope) of the evolutionary principles of adaptive function in the animal nervous system. The brain mechanisms that subserve tool use may bridge the gap between gesture and language--the site of such integration seems to be the parietal and extending opercular cortices.

  18. A call to action towards an evidence-based approach to using verbal encouragement during maximal exercise testing.

    Science.gov (United States)

    Midgley, Adrian W; Marchant, David C; Levy, Andrew R

    2017-07-24

    By definition, maximal exercise testing inherently requires participants to give a maximal effort. This is an important practical issue as submaximal efforts can produce invalid test results. Verbal encouragement is commonly used to motivate participants to maintain or increase effort investment during maximal exercise testing. Accordingly, studies have reported significant increases in time to exhaustion of between 8% and 18% during VO2max and multistage shuttle run tests, and a significant 30·5 m mean increase in 6-min walk test distance. Significant improvements during shorter tests, such as the Wingate and 2-min walk tests, have not been observed however. Although participants typically perceive verbal encouragement positively during maximal exercise testing, around one-third have neutral or negative perceptions. Despite the ubiquity and importance of verbal encouragement during maximal exercise testing, surprisingly little research has investigated the characteristics of effective encouragement with respect to its content, timing and frequency. The only randomized controlled trial to investigate one of these issues observed that verbal encouragement delivered every 20 s increased time to exhaustion during VO2 max testing, but not every 60 or 180 s. Of particular concern is that several exercise testing guidelines have incorporated specific guidelines for the use of verbal encouragement, but not provided any theoretical or empirical justification, presumably because of the limited research to inform practice. Recent empirical research does provide some important insight into participant preference for the content and timing of verbal encouragement during maximal exercise testing; however, much more research is clearly required to establish comprehensive evidence-based guidelines. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  19. Neural dynamics based on the recognition of neural fingerprints

    Directory of Open Access Journals (Sweden)

    José Luis eCarrillo-Medina

    2015-03-01

    Full Text Available Experimental evidence has revealed the existence of characteristic spiking features in different neural signals, e.g. individual neural signatures identifying the emitter or functional signatures characterizing specific tasks. These neural fingerprints may play a critical role in neural information processing, since they allow receptors to discriminate or contextualize incoming stimuli. This could be a powerful strategy for neural systems that greatly enhances the encoding and processing capacity of these networks. Nevertheless, the study of information processing based on the identification of specific neural fingerprints has attracted little attention. In this work, we study (i the emerging collective dynamics of a network of neurons that communicate with each other by exchange of neural fingerprints and (ii the influence of the network topology on the self-organizing properties within the network. Complex collective dynamics emerge in the network in the presence of stimuli. Predefined inputs, i.e. specific neural fingerprints, are detected and encoded into coexisting patterns of activity that propagate throughout the network with different spatial organization. The patterns evoked by a stimulus can survive after the stimulation is over, which provides memory mechanisms to the network. The results presented in this paper suggest that neural information processing based on neural fingerprints can be a plausible, flexible and powerful strategy.

  20. Analyses of fugu hoxa2 genes provide evidence for subfunctionalization of neural crest cell and rhombomere cis-regulatory modules during vertebrate evolution.

    Science.gov (United States)

    McEllin, Jennifer A; Alexander, Tara B; Tümpel, Stefan; Wiedemann, Leanne M; Krumlauf, Robb

    2016-01-15

    Hoxa2 gene is a primary player in regulation of craniofacial programs of head development in vertebrates. Here we investigate the evolution of a Hoxa2 neural crest enhancer identified originally in mouse by comparing and contrasting the fugu hoxa2a and hoxa2b genes with their orthologous teleost and mammalian sequences. Using sequence analyses in combination with transgenic regulatory assays in zebrafish and mouse embryos we demonstrate subfunctionalization of regulatory activity for expression in hindbrain segments and neural crest cells between these two fugu co-orthologs. hoxa2a regulatory sequences have retained the ability to mediate expression in neural crest cells while those of hoxa2b include cis-elements that direct expression in rhombomeres. Functional dissection of the neural crest regulatory potential of the fugu hoxa2a and hoxa2b genes identify the previously unknown cis-element NC5, which is implicated in generating the differential activity of the enhancers from these genes. The NC5 region plays a similar role in the ability of this enhancer to mediate reporter expression in mice, suggesting it is a conserved component involved in control of neural crest expression of Hoxa2 in vertebrate craniofacial development.

  1. How early is infants’ attention to objects and actions shaped by culture? New evidence from 24-month-olds raised in the US and China

    Directory of Open Access Journals (Sweden)

    Sandra R Waxman

    2016-02-01

    Full Text Available Researchers have proposed that the culture in which we are raised shapes the way that we attend to the objects and events that surround us. What remains unclear, however, is how early any such culturally-inflected differences emerge in development. Here, we address this issue directly, asking how 24-month-old infants from the US and China deploy their attention to objects and actions in dynamic scenes. By analyzing infants’ eye movements while they observed dynamic scenes, the current experiment revealed striking convergences, overall, in infants’ patterns of visual attention in the two communities, but also pinpointed a brief period during which their attention reliably diverged. This divergence, though modest, suggested that infants from the US devoted relatively more attention to the objects and those from China devoted relatively more attention to the actions in which they were engaged. This provides the earliest evidence for strong overlap in infants’ attention to objects and events in dynamic scenes, but also raises the possibility that by 24 months, infants’ attention may also be shaped subtly by the culturally-inflected attentional proclivities characteristic of adults in their cultural communities.

  2. How Early is Infants' Attention to Objects and Actions Shaped by Culture? New Evidence from 24-Month-Olds Raised in the US and China.

    Science.gov (United States)

    Waxman, Sandra R; Fu, Xiaolan; Ferguson, Brock; Geraghty, Kathleen; Leddon, Erin; Liang, Jing; Zhao, Min-Fang

    2016-01-01

    Researchers have proposed that the culture in which we are raised shapes the way that we attend to the objects and events that surround us. What remains unclear, however, is how early any such culturally-inflected differences emerge in development. Here, we address this issue directly, asking how 24-month-old infants from the US and China deploy their attention to objects and actions in dynamic scenes. By analyzing infants' eye movements while they observed dynamic scenes, the current experiment revealed striking convergences, overall, in infants' patterns of visual attention in the two communities, but also pinpointed a brief period during which their attention reliably diverged. This divergence, though modest, suggested that infants from the US devoted relatively more attention to the objects and those from China devoted relatively more attention to the actions in which they were engaged. This provides the earliest evidence for strong overlap in infants' attention to objects and events in dynamic scenes, but also raises the possibility that by 24 months, infants' attention may also be shaped subtly by the culturally-inflected attentional proclivities characteristic of adults in their cultural communities.

  3. [Interactive Knowledge to Action in Health Promotion: The GESTALT Project. Initial Results of a Pilot Study on Sustainable Implementation of an Evidence-Based Programme].

    Science.gov (United States)

    Rütten, A; Wolff, A; Streber, A

    2016-06-01

    The present article outlines a pilot study to demonstrate the concept of the interactive knowledge to action approach in order to foster sustainable implementation of an evidence-based physical activity programme for dementia prevention into practice. The approach and procedures will be introduced, and initial results of the pilot study "GESTALT", with special regard to the interplay of science, politics and prevention practice, will be outlined. In the GESTALT project (2011-2014) the concept of interactive knowledge to action was realised through a cooperative planning approach that systematically engaged and involved stakeholders from science, politics and practice. Evaluation of the project's sustainability focused on 3 dimensions: target group, organisations and context. Target group analysis included assessment of changes in physical activity behaviour (n=75). Organisational and context evaluations included an analysis of relevant documentation of cooperative planning meetings, conduction of the programme, bilateral talks and further meetings. In relation to the target group, the majority of participants (60%) were committed to an active lifestyle 6 months after completion of the GESTALT programme. Regarding organisations and context, 14 partner organisations maintained active engagement in cooperative planning processes. After adapting the GESTALT programme to the context and needs of the organisations and participants, 5 organisations were able to implement it. These same organisations also continued to provide exercise classes for ex-participants of the initial GESTALT programme. Through developing partnerships, increasing publicity and attracting policy makers, resources for the sustainable implementation of the GESTALT project were obtained. The pilot study GESTALT shows that the concept of interactive knowledge to action has substantially contributed to the sustainability of a physical activity programme in the field of dementia prevention. For this

  4. Innoversity in knowledge-for-action and adaptation to climate change: the first steps of an 'evidence-based climatic health' transfrontier training program

    Directory of Open Access Journals (Sweden)

    Véronique Lapaige

    2010-12-01

    Full Text Available Véronique Lapaige1–3, Hélène Essiembre41Department of Psychiatry, University of Montreal, Montreal, QC, Canada; 2Fernand-Seguin Research Centre, Montreal, QC, Canada; 3Quebec National Public Health Institute; 4Industrial and Organizational Program, Department of Psychology, University of Montreal, Montreal, QC, CanadaAbstract: It has become increasingly clear to the international scientific community that climate change is real and has important consequences for human health. To meet these new challenges, the World Health Organization recommends reinforcing the adaptive capacity of health systems. One of the possible avenues in this respect is to promote awareness and knowledge translation in climatic health, at both the local and global scales. Within such perspective, two major themes have emerged in the field of public health research: 1 the development of advanced training adapted to 'global environment' change and to the specific needs of various groups of actors (doctors, nurses, public health practitioners, health care managers, public service managers, local communities, etc and 2 the development of strategies for implementing research results and applying various types of evidence to the management of public health issues affected by climate change. Progress on these two fronts will depend on maximum innovation in transdisciplinary and transsectoral collaborations. The general purpose of this article is to present the program of a new research and learning chair designed for this double set of developmental objectives – a chair that emphasizes 'innoversity' (the dynamic relationship between innovation and diversity and 'transfrontier ecolearning for adaptive actions'. The Écoapprentissages, santé mentale et climat collaborative research chair (University of Montreal and Quebec National Public Health Institute based in Montreal is a center for 'transdisciplinary research' on the transfrontier knowledge-for-action that can aid

  5. Cancer mode of action, weight of evidence, and proposed cancer reference value for hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).

    Science.gov (United States)

    Sweeney, Lisa M; Okolica, Michelle R; Gut, Chester P; Gargas, Michael L

    2012-11-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX, CAS No. 121-82-4) is a component of munitions formulations, and has been detected in groundwater samples collected at various US military sites. Clean up target levels for RDX may be derived based on consideration of acceptable cumulative human exposure as expressed in toxicity reference values. Evaluations of the cancer weight of evidence and possible modes of action (MOA) for RDX-induced cancer were conducted. It was concluded that the available data provide suggestive evidence of human carcinogenic potential for RDX. While a mutagenic/genotoxic MOA for RDX is unlikely, no alterative MOA is strongly supported by the available data. A nonlinear (threshold) approach to the assessment of human cancer risk was recommended, and a recommended chronic cancer reference dose of 0.08mg/kg/day was derived. For comparison only, computations using a linear approach were also conducted, yielding a cancer risk specific dose of 0.000235mg/kg/day for 1 in 10(5) risk; this value is 2.6-fold higher the current US EPA risk specific dose for 1 in 10(5) risk. Thus, cleanup standards based on human health risk from RDX exposure could potentially depend on the willingness of risk managers to accept a nonlinear MOA and nonlinear toxicity risk value derivation. Published by Elsevier Inc.

  6. The neural crest and neural crest cells: discovery and significance for theories of embryonic organization

    Indian Academy of Sciences (India)

    Brian K Hall

    2008-12-01

    The neural crest has long fascinated developmental biologists, and, increasingly over the past decades, evolutionary and evolutionary developmental biologists. The neural crest is the name given to the fold of ectoderm at the junction between neural and epidermal ectoderm in neurula-stage vertebrate embryos. In this sense, the neural crest is a morphological term akin to head fold or limb bud. This region of the dorsal neural tube consists of neural crest cells, a special population(s) of cell, that give rise to an astonishing number of cell types and to an equally astonishing number of tissues and organs. Neural crest cell contributions may be direct — providing cells — or indirect — providing a necessary, often inductive, environment in which other cells develop. The enormous range of cell types produced provides an important source of evidence of the neural crest as a germ layer, bringing the number of germ layers to four — ectoderm, endoderm, mesoderm, and neural crest. In this paper I provide a brief overview of the major phases of investigation into the neural crest and the major players involved, discuss how the origin of the neural crest relates to the origin of the nervous system in vertebrate embryos, discuss the impact on the germ-layer theory of the discovery of the neural crest and of secondary neurulation, and present evidence of the neural crest as the fourth germ layer. A companion paper (Hall, Evol. Biol. 2008) deals with the evolutionary origins of the neural crest and neural crest cells.

  7. Molecular mapping of the origin of postnatal spinal cord ependymal cells: evidence that adult ependymal cells are derived from Nkx6.1+ ventral neural progenitor cells.

    Science.gov (United States)

    Fu, Hui; Qi, Yingchuan; Tan, Min; Cai, Jun; Hu, Xuemei; Liu, Zijing; Jensen, Jan; Qiu, Mengsheng

    2003-02-10

    Recent studies have suggested that the ependymal cells lining the central canal of postnatal spinal cord possess certain properties of neural stem cells. However, the embryonic origin and developmental potential of the postnatal spinal cord ependymal cells remain to be defined. In this report, we investigated the developmental origin of postnatal spinal ependymal cells by studying the dynamic expression of several neural progenitor genes that are initially expressed in distinct domains of neuroepithelium in young embryos. At later stages of development, as the ventricular zone of the embryonic spinal cord is reduced, expression of Nkx6.1 progenitor gene is constantly detected in ependymal cells throughout chick and mouse development. Expression of other neural progenitor genes that lie either dorsal or ventral to the Nkx6.1+ domain is gradually decreased and eventually disappeared. These results suggest that the remaining neuroepithelial cells at later stages of animal life are derived from the Nkx6.1+ ventral neuroepithelial cells. Expression of Nkx6.1 in the remaining neuroepithelium is closely associated with, and regulated by, Shh expression in the floor plate. In addition, we suggested that the Nkx6.1+ ependymal cells in adult mouse spinal cords may retain the proliferative property of neural stem cells.

  8. Evidence from pupillometry and fMRI indicates reduced neural response during vicarious social pain but not physical pain in autism

    NARCIS (Netherlands)

    Krach, Sören; Kamp-Becker, Inge; Einhäuser, Wolfgang; Sommer, Jens; Frässle, Stefan; Jansen, Andreas; Rademacher, Lena; Müller-Pinzler, Laura; Gazzola, V.; Paulus, Frieder M

    2015-01-01

    Autism spectrum disorder (ASD) is characterized by substantial social deficits. The notion that dysfunctions in neural circuits involved in sharing another's affect explain these deficits is appealing, but has received only modest experimental support. Here we evaluated a complex paradigm on the vic

  9. Priorities for action on the social determinants of health: Empirical evidence on the strongest associations with life expectancy in 54 low-income countries, 1990-2012.

    Science.gov (United States)

    Hauck, K; Martin, S; Smith, P C

    2016-10-01

    The WHO Commission on the Social Determinants of Health set out an impressive collection of policy proposals on the social determinants of health. However, a serious weakness for securing implementation is the difficulty for policymakers in identifying priorities for action. The objective of this study is to determine a small set of the most influential determinants using existing data and an empirical approach. 45 Indicators from the World Bank's World Development Indicators are selected to measure attainment for the determinants proposed by the Commission. Panel data models of life expectancy at birth for 54 low-income countries over the years 1990-2012 (1188 country-years) are estimated. Each determinant is subjected to a robustness test using Extreme Bound Analysis, to determine the stability of its estimated impact on life expectancy. For 20 robust and significant determinants the magnitude of association with life expectancy is determined. The largest average increases in life expectancy at 14.5 months per capita is associated with a one standard deviation reduction in HIV prevalence among children, followed by advances in gender equality at 9.4 months. Improvements in life expectancy between 6 and 9 months are associated with agricultural production, political stability, access to clean water and sanitation, good governance, and primary school enrolment. Improvements below 6 months are associated with increases in private health expenditure and overseas development assistance, and control of armed conflict and HIV prevalence among men. There is no evidence that national income, public spending on healthcare and education, secondary schooling, terms of international trade, employment, debt service and relief, out-of-pocket expenditures, agricultural ex- or imports, lifestock production, foreign investment, urbanization or environmental degradation are robustly associated with population health. Results provide support for the relevance of some proposed

  10. Perception, action, and Roelofs effect: a mere illusion of dissociation.

    Directory of Open Access Journals (Sweden)

    Paul Dassonville

    2004-11-01

    Full Text Available A prominent and influential hypothesis of vision suggests the existence of two separate visual systems within the brain, one creating our perception of the world and another guiding our actions within it. The induced Roelofs effect has been described as providing strong evidence for this perception/action dissociation: When a small visual target is surrounded by a large frame positioned so that the frame's center is offset from the observer's midline, the perceived location of the target is shifted in the direction opposite the frame's offset. In spite of this perceptual mislocalization, however, the observer can accurately guide movements to the target location. Thus, perception is prone to the illusion while actions seem immune. Here we demonstrate that the Roelofs illusion is caused by a frame-induced transient distortion of the observer's apparent midline. We further demonstrate that actions guided to targets within this same distorted egocentric reference frame are fully expected to be accurate, since the errors of target localization will exactly cancel the errors of motor guidance. These findings provide a mechanistic explanation for the various perceptual and motor effects of the induced Roelofs illusion without requiring the existence of separate neural systems for perception and action. Given this, the behavioral dissociation that accompanies the Roelofs effect cannot be considered evidence of a dissociation of perception and action. This indicates a general need to re-evaluate the broad class of evidence purported to support this hypothesized dissociation.

  11. Pleiotropic Actions of Peroxisome Proliferator-Activated Receptors (PPARs) in Dysregulated Metabolic Homeostasis, Inflammation and Cancer: Current Evidence and Future Perspectives

    Science.gov (United States)

    Laganà, Antonio Simone; Vitale, Salvatore Giovanni; Nigro, Angela; Sofo, Vincenza; Salmeri, Francesca Maria; Rossetti, Paola; Rapisarda, Agnese Maria Chiara; La Vignera, Sandro; Condorelli, Rosita Angela; Rizzo, Gianluca; Buscema, Massimo

    2016-01-01

    Background: Peroxisome proliferator-activated receptors (PPARs) have demonstrated a lot of important effects in the regulation of glucose and lipid metabolism and in the correct functioning of adipose tissue. Recently, many studies have evaluated a possible effect of PPARs on tumor cells. The purpose of this review is to describe the effects of PPARs, their action and their future prospective; Methods: Narrative review aimed to synthesize cutting-edge evidence retrieved from searches of computerized databases; Results: PPARs play a key role in metabolic diseases, which include several cardiovascular diseases, insulin resistance, type 2 diabetes, metabolic syndrome, impaired immunity and the increasing risk of cancer; in particular, PPARα and PPARβ/δ mainly enable energy combustion, while PPARγ contributes to energy storage by enhancing adipogenesis; Conclusion: PPAR agonists could represent interesting types of molecules that can treat not only metabolic diseases, but also inflammation and cancer. Additional research is needed for the identification of high-affinity, high-specificity agonists for the treatment of obesity, type 2 diabetes (T2DM) and other metabolic diseases. Further studies are needed also to elucidate the role of PPARs in cancer. PMID:27347932

  12. Further evidences for the mode of action of the larvicidal m-pentadecadienyl-phenol isolated from Myracrodruon urundeuva seeds against Aedes aegypti.

    Science.gov (United States)

    Souza, Terezinha M; Menezes, Erika S Bezerra; Oliveira, Rodrigo V; Almeida Filho, Luiz Carlos P; Martins, Jorge M; Moreno, Frederico B; Monteiro-Moreira, Ana Cristina O; Moura, Arlindo A Araripe; Carvalho, Ana F Urano

    2015-12-01

    Nowadays, dengue fever is considered the most important arbovirosis worldwide and its control is still based upon combating the vector Aedes aegypti. Besides monitoring of mosquito populations resistant to conventional insecticides, the search for new environmentally safe insecticides and conduction of molecular studies focusing on the elucidation of mode of action and possible resistance mechanisms are considered the key for a sustainable management of the mosquito vector. Thus, the present work aimed to assess changes in protein expression of 3rd-instar larvae of Ae. aegypti after exposure to the natural insecticide m-pentadecadienyl-phenol. Bidimensional electrophoresis followed by mass spectrometry resulted in identification of 12 proteins differentially expressed between control and treated groups. Larvae exposed to the toxic compound for 24h showed elevated detoxification response (glutathione-S-transferase), increased levels of stress-related proteins (HSP70) as well as evidence of lysosome stabilization to enable survival. Furthermore, expression of proteins involved in protection of peritrophic membrane and metabolism of lipids indicated systemic effect of toxic effects in treated larvae.

  13. Pleiotropic Actions of Peroxisome Proliferator-Activated Receptors (PPARs) in Dysregulated Metabolic Homeostasis, Inflammation and Cancer: Current Evidence and Future Perspectives.

    Science.gov (United States)

    Laganà, Antonio Simone; Vitale, Salvatore Giovanni; Nigro, Angela; Sofo, Vincenza; Salmeri, Francesca Maria; Rossetti, Paola; Rapisarda, Agnese Maria Chiara; La Vignera, Sandro; Condorelli, Rosita Angela; Rizzo, Gianluca; Buscema, Massimo

    2016-06-24

    Peroxisome proliferator-activated receptors (PPARs) have demonstrated a lot of important effects in the regulation of glucose and lipid metabolism and in the correct functioning of adipose tissue. Recently, many studies have evaluated a possible effect of PPARs on tumor cells. The purpose of this review is to describe the effects of PPARs, their action and their future prospective; Narrative review aimed to synthesize cutting-edge evidence retrieved from searches of computerized databases; PPARs play a key role in metabolic diseases, which include several cardiovascular diseases, insulin resistance, type 2 diabetes, metabolic syndrome, impaired immunity and the increasing risk of cancer; in particular, PPARα and PPARβ/δ mainly enable energy combustion, while PPARγ contributes to energy storage by enhancing adipogenesis; PPAR agonists could represent interesting types of molecules that can treat not only metabolic diseases, but also inflammation and cancer. Additional research is needed for the identification of high-affinity, high-specificity agonists for the treatment of obesity, type 2 diabetes (T2DM) and other metabolic diseases. Further studies are needed also to elucidate the role of PPARs in cancer.

  14. Pleiotropic Actions of Peroxisome Proliferator-Activated Receptors (PPARs in Dysregulated Metabolic Homeostasis, Inflammation and Cancer: Current Evidence and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Antonio Simone Laganà

    2016-06-01

    Full Text Available Background: Peroxisome proliferator-activated receptors (PPARs have demonstrated a lot of important effects in the regulation of glucose and lipid metabolism and in the correct functioning of adipose tissue. Recently, many studies have evaluated a possible effect of PPARs on tumor cells. The purpose of this review is to describe the effects of PPARs, their action and their future prospective; Methods: Narrative review aimed to synthesize cutting-edge evidence retrieved from searches of computerized databases; Results: PPARs play a key role in metabolic diseases, which include several cardiovascular diseases, insulin resistance, type 2 diabetes, metabolic syndrome, impaired immunity and the increasing risk of cancer; in particular, PPARα and PPARβ/δ mainly enable energy combustion, while PPARγ contributes to energy storage by enhancing adipogenesis; Conclusion: PPAR agonists could represent interesting types of molecules that can treat not only metabolic diseases, but also inflammation and cancer. Additional research is needed for the identification of high-affinity, high-specificity agonists for the treatment of obesity, type 2 diabetes (T2DM and other metabolic diseases. Further studies are needed also to elucidate the role of PPARs in cancer.

  15. Distribution of Müller stem cells within the neural retina: evidence for the existence of a ciliary margin-like zone in the adult human eye.

    Science.gov (United States)

    Bhatia, Bhairavi; Singhal, Shweta; Lawrence, Jean M; Khaw, Peng T; Limb, G Astrid

    2009-09-01

    Much interest has been generated by the identification of neural stem cells in the human neural retina and ciliary body. However, it is not clear whether stem cells identified in these ocular compartments are of the same origin or whether they ontogenically derive from different cell populations. This study examined the in situ anatomical distribution of these cells within the neural retina and ciliary body, as well as their ability to proliferate in response to EGF. Human retinae and ciliary body were examined for co-expression of Nestin, cellular retinaldehyde binding (CRALBP) or Vimentin, and the stem cell markers SOX2, CHX10, NOTCH1 and SHH. Retinal explants were cultured with epidermal growth factor (EGF) to assess retinal cell proliferation. Intense Nestin and CRALBP staining was observed in the neural retinal margin, where cells formed bundles of spindle cells (resembling glial cells) that lacked lamination and co-stained for SOX2, CHX10 and SHH. This staining differentiated the neural retina from the ciliary epithelium, which expressed SOX2, CHX10 and NOTCH1 but not Nestin or CRALBP. Nestin and CRALBP expression decreased towards the posterior retina, where it anatomically identified a population of Müller glia. All Vimentin positive Müller glia co-stained for SOX2, but only few Vimentin positive cells expressed Nestin and SOX2. Cells of the retinal margin and the inner nuclear layer (INL), where the soma of Müller glia predominate, re-entered the cell cycle upon retinal explant culture with EGF. Lack of lamination and abundance of Müller glia expressing stem cell markers in the marginal region of the adult human retina resemble the ciliary marginal zone (CMZ) of fish and amphibians. The findings that cells in this CM-like zone, as well in the inner nuclear layer proliferate in response to EGF suggest that the adult human retina has regenerative potential. Identification of factors that may promote retinal regeneration in the adult human eye would

  16. Modeling the value of strategic actions in the superior colliculus

    Directory of Open Access Journals (Sweden)

    Dhushan Thevarajah

    2010-02-01

    Full Text Available In learning models of strategic game play, an agent constructs a valuation (action value over possible future choices as a function of past actions and rewards. Choices are then stochastic functions of these action values. Our goal is to uncover a neural signal that correlates with the action value posited by behavioral learning models. We measured activity from neurons in the superior colliculus (SC, a midbrain region involved in planning saccadic eye movements, in monkeys while they performed two saccade tasks. In the strategic task, monkeys competed against a computer in a saccade version of the mixed-strategy game “matching-pennies”. In the instructed task, stochastic saccades were elicited through explicit instruction rather than free choices. In both tasks, neuronal activity and behavior were shaped by past actions and rewards with more recent events exerting a larger influence. Further, SC activity predicted upcoming choices during the strategic task and upcoming reaction times during the instructed task. Finally, we found that neuronal activity in both tasks correlated with an established learning model, the Experience Weighted Attraction model of action valuation (Ho, Camerer, and Chong, 2007. Collectively, our results provide evidence that action values hypothesized by learning models are represented in the motor planning regions of the brain in a manner that could be used to select strategic actions.

  17. Evidence from pharmacology and pathophysiology suggests that chemicals with dissimilar mechanisms of action could be of bigger concern in the toxicological risk assessment of chemical mixtures than chemicals with a similar mechanism of action

    DEFF Research Database (Denmark)

    Hadrup, Niels

    2014-01-01

    mechanisms of action, similar modes of action or with common target organs. In the European Union, efforts are currently being made to subgroup chemicals according to this need. However, it remains to be determined whether this is the best strategy to obtain data for risk assessment. In conditions...... such as cancer or HIV, it is generally recognised that pharmacological combination therapy targeting different mechanisms of action is more effective than a strategy where only one mechanism is targeted. Moreover, in diseases such as acute myocardial infarction and congestive heart failure, several organ systems...

  18. Perception, action, and word meanings in the human brain: the case from action verbs.

    Science.gov (United States)

    Bedny, Marina; Caramazza, Alfonso

    2011-04-01

    Among other things, humans talk about what they perceive and do, like "glowing,"hopping," and "squeaking." What is the relationship between our sensory-motor experiences and word meanings? Does understanding action-verbs rely on the same neural circuits as seeing and acting? The available evidence indicates that sensory-motor experience and word meanings are represented in distinct, but interacting systems. Understanding action-verbs does not rely on early modality-specific visual or motor circuits. Instead, word comprehension relies on a network of amodal brain regions in the left frontal, temporal, and parietal cortices that represent conceptual and grammatical properties of words. Interactions between word meanings and sensory-motor experiences occur in higher-order polymodal brain regions. © 2011 New York Academy of Sciences.

  19. Imaging the neural mechanisms of TMS neglect-like bias in healthy volunteers with the interleaved TMS/fMRI technique: preliminary evidence

    Directory of Open Access Journals (Sweden)

    Raffaella eRicci

    2012-12-01

    Full Text Available Applying a precisely timed pulse of Transcranial Magnetic Stimulation (TMS over the right posterior parietal cortex (PPC can produce temporary visuo-spatial neglect-like effects. Although the TMS is applied over PPC, it is not clear what other brain regions are involved. We applied TMS within a functional Magnetic Resonance Imaging (fMRI scanner to investigate brain activity during TMS induction of neglect-like bias in three healthy volunteers, while they performed a line bisection judgment task (i.e. the landmark task. Single-pulse TMS at 115% of motor threshold was applied 150 ms after the visual stimulus onset. Participants completed two different TMS/fMRI sessions while performing this task: one session while single-pulse TMS was intermittently and time-locked applied to the right PPC and a control session with TMS positioned over the vertex. Perceptual rightward bias was observed when TMS was delivered over the right PPC. During neglect-like behavior, the fMRI maps showed decreased neural activity within parieto-frontal areas which are often lesioned or dysfunctional in patients with left neglect. Vertex TMS induced behavioral effects compatible with leftward response bias and increased BOLD signal in the left caudate (a site which has been linked to response bias. These results are discussed in relation to recent findings on neural networks subserving attention in space.

  20. Imaging the neural mechanisms of TMS neglect-like bias in healthy volunteers with the interleaved TMS/fMRI technique: preliminary evidence.

    Science.gov (United States)

    Ricci, Raffaella; Salatino, Adriana; Li, Xingbao; Funk, Agnes P; Logan, Sarah L; Mu, Qiwen; Johnson, Kevin A; Bohning, Daryl E; George, Mark S

    2012-01-01

    Applying a precisely timed pulse of transcranial magnetic stimulation (TMS) over the right posterior parietal cortex (PPC) can produce temporary visuo-spatial neglect-like effects. Although the TMS is applied over PPC, it is not clear what other brain regions are involved. We applied TMS within a functional magnetic resonance imaging (fMRI) scanner to investigate brain activity during TMS induction of neglect-like bias in three healthy volunteers, while they performed a line bisection judgment task (i.e., the landmark task). Single-pulse TMS at 115% of motor threshold was applied 150 ms after the visual stimulus onset. Participants completed two different TMS/fMRI sessions while performing this task: one session while single-pulse TMS was intermittently and time-locked applied to the right PPC and a control session with TMS positioned over the vertex. Perceptual rightward bias was observed when TMS was delivered over the right PPC. During neglect-like behavior, the fMRI maps showed decreased neural activity within parieto-frontal areas, which are often lesioned or dysfunctional in patients with left neglect. Vertex TMS induced behavioral effects compatible with leftward response bias and increased BOLD signal in the left caudate (a site which has been linked to response bias). These results are discussed in relation to recent findings on neural networks subserving attention in space.

  1. Evidence for electrical remodelling of the atrial myocardium in patients with atrial fibrillation. A study using the monophasic action potential recording technique.

    Science.gov (United States)

    Hertervig, Eva J; Yuan, Shiwen; Carlson, Jonas; Kongstad-Rasmussen, Ole; Olsson, S Bertil

    2002-01-01

    Experimental studies have shown that remodelling of the atrial myocardium is linked to the occurrence and perpetuation of atrial fibrillation (AF). Clinical evidence, however, is insufficient. We recorded monophasic action potentials (MAP) during AF from one to three sites in the right atrium in seven patients with chronic AF (CAF) and in 11 patients with paroxysmal AF (PAF). The fibrillatory (FF) interval between two consecutive upstrokes of the MAP was measured using a computer-assisted manual method. The mean, median, 15th, 10th, 5th percentile and shortest FF intervals were calculated in each patient and used as estimates of the local atrial effective refractory period (AERP) during AF. In three patients burst pacing at 400 and 500 beats min(-1) was delivered during the MAP recording. In nine patients, the AERP was also tested using the extra stimulus technique during sinus rhythm. Thirty-eight recordings were obtained. The shortest FF interval was significantly shorter in patients with CAF as compared with that in patients with PAF (50+/-13 vs. 72+/-31 ms, P<005). Similar differences were seen in the mean, median, 15th, 10th, and 5th percentile FF interval. The AERP during sinusrhythm was significantly longer than the estimated AERPs (P<0 05 to P<0.01) in the nine patients. There was no significant difference in FF interval before and after the burst pacing in the three patients. The AERP was significantly shortened during AF, as compared with that during sinus rhythm, and the AERP shortening was more marked in patients with CAF than in patients with PAF. These clinical findings support the connection between the electrical remodelling and the occurrence and/ or perpetuation of the AF.

  2. Neural Circuits Trained with Standard Reinforcement Learning Can Accumulate Probabilistic Information during Decision Making.

    Science.gov (United States)

    Kurzawa, Nils; Summerfield, Christopher; Bogacz, Rafal

    2017-02-01

    Much experimental evidence suggests that during decision making, neural circuits accumulate evidence supporting alternative options. A computational model well describing this accumulation for choices between two options assumes that the brain integrates the log ratios of the likelihoods of the sensory inputs given the two options. Several models have been proposed for how neural circuits can learn these log-likelihood ratios from experience, but all of these models introduced novel and specially dedicated synaptic plasticity rules. Here we show that for a certain wide class of tasks, the log-likelihood ratios are approximately linearly proportional to the expected rewards for selecting actions. Therefore, a simple model based on standard reinforcement learning rules is able to estimate the log-likelihood ratios from experience and on each trial accumulate the log-likelihood ratios associated with presented stimuli while selecting an action. The simulations of the model replicate experimental data on both behavior and neural activity in tasks requiring accumulation of probabilistic cues. Our results suggest that there is no need for the brain to support dedicated plasticity rules, as the standard mechanisms proposed to describe reinforcement learning can enable the neural circuits to perform efficient probabilistic inference.

  3. Neural processing of race during imitation: self-similarity versus social status.

    Science.gov (United States)

    Losin, Elizabeth A Reynolds; Cross, Katy A; Iacoboni, Marco; Dapretto, Mirella

    2014-04-01

    People preferentially imitate others who are similar to them or have high social status. Such imitative biases are thought to have evolved because they increase the efficiency of cultural acquisition. Here we focused on distinguishing between self-similarity and social status as two candidate mechanisms underlying neural responses to a person's race during imitation. We used fMRI to measure neural responses when 20 African American (AA) and 20 European American (EA) young adults imitated AA, EA and Chinese American (CA) models and also passively observed their gestures and faces. We found that both AA and EA participants exhibited more activity in lateral frontoparietal and visual regions when imitating AAs compared with EAs or CAs. These results suggest that racial self-similarity is not likely to modulate neural responses to race during imitation, in contrast with findings from previous neuroimaging studies of face perception and action observation. Furthermore, AA and EA participants associated AAs with lower social status than EAs or CAs, suggesting that the social status associated with different racial groups may instead modulate neural activity during imitation of individuals from those groups. Taken together, these findings suggest that neural responses to race during imitation are driven by socially learned associations rather than self-similarity. This may reflect the adaptive role of imitation in social learning, where learning from higher status models can be more beneficial. This study provides neural evidence consistent with evolutionary theories of cultural acquisition.

  4. Power effects on cognitive control: Turning conflict into action.

    Science.gov (United States)

    Schmid, Petra C; Kleiman, Tali; Amodio, David M

    2015-06-01

    Power is known to promote effective goal pursuit, especially when it requires one to overcome distractions or bias. We proposed that this effect involves the ability to engage and implement cognitive control. In Study 1, we demonstrated that power enhances behavioral performance on a response conflict task and that it does so by enhancing controlled processing rather than by reducing automatic processing. In Study 2, we used an event-related potential index of anterior cingulate activity to test whether power effects on control were due to enhanced conflict sensitivity or action implementation. Power did not significantly affect neural sensitivity to conflict; rather, high power was associated with a stronger link between conflict processing and intended action, relative to low power. These findings suggest a new perspective on how social factors can affect controlled processing and offer new evidence regarding the transition between conflict detection and the implementation of action control.

  5. Immunocytochemical studies reveal novel neural structures in nemertean pilidium larvae and provide evidence for incorporation of larval components into the juvenile nervous system.

    Science.gov (United States)

    Hindinger, Sabine; Schwaha, Thomas; Wanninger, Andreas

    2013-05-23

    Nemertea is one of the least studied lophotrochozoan phyla concerning neurogenesis. The sparse data available do not unambiguously allow for answering questions with respect to the neural groundplan of the phylum or the fate of larval neural structures during metamorphosis. In order to contribute to this issue, we studied neurotransmitter distribution during development of the pilidiophoran Lineus albocinctus Verrill, 1900. Two serotonin-like immunoreactive (lir) neurons are present in the anterior part of the apical plate. They send numerous processes into the four lobes of the pilidium larva, where they form a complex subepithelial nerve net. All four larval lobes are underlain by a marginal neurite bundle, which is associated with numerous serotonin-lir monociliated perikarya. A serotonin-lir oral nerve ring encircles the stomach sphincter and is associated with few serotonin-lir conical cells. Two suboral neurites descend from the oral nerve ring and merge with the marginal neurite bundle. The oral nerve ring and the suboral neurites contain the mollusk-specific VD1/RPD2 α-neuropeptide. The lateral lobes of the larva have three and the anterior and the posterior lobes two VD1/RPD2-lir marginal neurite bundles. The lobar FMRFamide-lir plexus of Lineus albocinctus is much more complex than previously described for any pilidium larva. It includes a circumesophageal neurite that descends along each side of the larval esophagus and together with the inner marginal neurite bundle gives rise to the lobar plexus of the lateral lobes. An outer FMRFamide-lir marginal neurite bundle with numerous associated FMRFamide-lir marginal sensory cells surrounds all four lobes. FMRFamide-lir structures are absent in the larval apical region. The oral nerve ring and the two suboral serotonin-lir neurites are incorporated into the juvenile nervous system. Our study confirms the presence of serotonin-lir components in the apical region of the pilidium larva of Lineus albocinctus and

  6. Understanding the Goals of Everyday Instrumental Actions Is Primarily Linked to Object, Not Motor-Kinematic, Information: Evidence from fMRI

    Science.gov (United States)

    Nicholson, Toby; Roser, Matt; Bach, Patric

    2017-01-01

    Prior research conceptualised action understanding primarily as a kinematic matching of observed actions to own motor representations but has ignored the role of object information. The current study utilized fMRI to identify (a) regions uniquely involved in encoding the goal of others’ actions, and (b) to test whether these goal understanding processes draw more strongly on regions involved in encoding object semantics or movement kinematics. Participants watched sequences of instrumental actions while attending to either the actions’ goal (goal task), the movements performed (movement task) or the objects used (object task). The results confirmed, first, a unique role of the inferior frontal gyrus, middle temporal gyrus and medial frontal gyrus in action goal understanding. Second, they show for the first time that activation in the goal task overlaps directly with object- but not movement-related activation. Moreover, subsequent parametric analyses revealed that movement-related regions become activated only when goals are unclear, or observers have little action experience. In contrast to motor theories of action understanding, these data suggest that objects—rather than movement kinematics—carry the key information about others’ actions. Kinematic information is additionally recruited when goals are ambiguous or unfamiliar. PMID:28081175

  7. Sensorimotor learning biases choice behavior: a learning neural field model for decision making.

    Directory of Open Access Journals (Sweden)

    Christian Klaes

    Full Text Available According to a prominent view of sensorimotor processing in primates, selection and specification of possible actions are not sequential operations. Rather, a decision for an action emerges from competition between different movement plans, which are specified and selected in parallel. For action choices which are based on ambiguous sensory input, the frontoparietal sensorimotor areas are considered part of the common underlying neural substrate for selection and specification of action. These areas have been shown capable of encoding alternative spatial motor goals in parallel during movement planning, and show signatures of competitive value-based selection among these goals. Since the same network is also involved in learning sensorimotor associations, competitive action selection (decision making should not only be driven by the sensory evidence and expected reward in favor of either action, but also by the subject's learning history of different sensorimotor associations. Previous computational models of competitive neural decision making used predefined associations between sensory input and corresponding motor output. Such hard-wiring does not allow modeling of how decisions are influenced by sensorimotor learning or by changing reward contingencies. We present a dynamic neural field model which learns arbitrary sensorimotor associations with a reward-driven Hebbian learning algorithm. We show that the model accurately simulates the dynamics of action selection with different reward contingencies, as observed in monkey cortical recordings, and that it correctly predicted the pattern of choice errors in a control experiment. With our adaptive model we demonstrate how network plasticity, which is required for association learning and adaptation to new reward contingencies, can influence choice behavior. The field model provides an integrated and dynamic account for the operations of sensorimotor integration, working memory and action

  8. CD24 expression identifies teratogen-sensitive fetal neural stem cell subpopulations: evidence from developmental ethanol exposure and orthotopic cell transfer models.

    Directory of Open Access Journals (Sweden)

    Joseph D Tingling

    Full Text Available BACKGROUND: Ethanol is a potent teratogen. Its adverse neural effects are partly mediated by disrupting fetal neurogenesis. The teratogenic process is poorly understood, and vulnerable neurogenic stages have not been identified. Identifying these is a prerequisite for therapeutic interventions to mitigate effects of teratogen exposures. METHODS: We used flow cytometry and qRT-PCR to screen fetal mouse-derived neurosphere cultures for ethanol-sensitive neural stem cell (NSC subpopulations, to study NSC renewal and differentiation. The identity of vulnerable NSC populations was validated in vivo, using a maternal ethanol exposure model. Finally, the effect of ethanol exposure on the ability of vulnerable NSC subpopulations to integrate into the fetal neurogenic environment was assessed following ultrasound guided, adoptive transfer. RESULTS: Ethanol decreased NSC mRNAs for c-kit, Musashi-1and GFAP. The CD24(+ NSC population, specifically the CD24(+CD15(+ double-positive subpopulation, was selectively decreased by ethanol. Maternal ethanol exposure also resulted in decreased fetal forebrain CD24 expression. Ethanol pre-exposed CD24(+ cells exhibited increased proliferation, and deficits in cell-autonomous and cue-directed neuronal differentiation, and following orthotopic transplantation into naïve fetuses, were unable to integrate into neurogenic niches. CD24(depleted cells retained neurosphere regeneration capacity, but following ethanol exposure, generated increased numbers of CD24(+ cells relative to controls. CONCLUSIONS: Neuronal lineage committed CD24(+ cells exhibit specific vulnerability, and ethanol exposure persistently impairs this population's cell-autonomous differentiation capacity. CD24(+ cells may additionally serve as quorum sensors within neurogenic niches; their loss, leading to compensatory NSC activation, perhaps depleting renewal capacity. These data collectively advance a mechanistic hypothesis for teratogenesis leading to

  9. Folate receptor alpha is necessary for neural plate cell apical constriction during Xenopus neural tube formation.

    Science.gov (United States)

    Balashova, Olga A; Visina, Olesya; Borodinsky, Laura N

    2017-03-02

    Folate supplementation prevents up to 70% of neural tube defects (NTDs), which result from a failure of neural tube closure during embryogenesis. The elucidation of the mechanisms underlying folate action has been challenging. This study introduces Xenopus laevis as a model to determine the cellular and molecular mechanisms involved in folate action during neural tube formation. We show that knockdown of folate receptor-α (FRα) impairs neural tube formation and leads to NTDs. FRα knockdown in neural plate cells only is necessary and sufficient to induce NTDs. FRα-deficient neural plate cells fail to constrict, resulting in widening of the neural plate midline and defective neural tube closure. Pharmacological inhibition of folate action by methotrexate during neurulation induces NTDs by inhibiting folate interaction with its uptake systems. Our findings support a model for folate receptor interacting with cell adhesion molecules, thus regulating apical cell membrane remodeling and cytoskeletal dynamics necessary for neural plate folding. Further studies in this organism may unveil novel cellular and molecular events mediated by folate and lead to new means for preventing NTDs.

  10. Feature Weight Tuning for Recursive Neural Networks

    OpenAIRE

    2014-01-01

    This paper addresses how a recursive neural network model can automatically leave out useless information and emphasize important evidence, in other words, to perform "weight tuning" for higher-level representation acquisition. We propose two models, Weighted Neural Network (WNN) and Binary-Expectation Neural Network (BENN), which automatically control how much one specific unit contributes to the higher-level representation. The proposed model can be viewed as incorporating a more powerful c...

  11. The role of BDNF in depression on the basis of its location in the neural circuitry

    Institute of Scientific and Technical Information of China (English)

    Hui YU; Zhe-yu CHEN

    2011-01-01

    Depression is one of the most prevalent and life-threatening forms of mental illnesses and the neural circuitry underlying depression remains incompletely understood. Most attention in the field has focused on hippocampal and frontal cortical regions for their roles in depression and antidepressant action. While these regions no doubt play important roles in the mental illness, there is compelling evi-dence that other brain regions are also involved. Brain-derived neurotrophic factor (BDNF) is broadly expressed in the developing and adult mammalian brain and has been implicated in development, neural regeneration, synaptic transmission, synaptic plasticity and neurogenesis. Recently BDNF has been shown to play an important role in the pathophysiology of depression, however there are con-troversial reports about the effects of BDNF on depression. Here, we present an overview of the current knowledge concerning BDNF actions and associated intracellular signaling in hippocampus, prefrontal cortex, nucleus accumbens (NAc) and amygdala as their rela-tion to depression.

  12. The representation of response effector and response location in episodic memory for newly acquired actions: evidence from retrieval-induced forgetting.

    Science.gov (United States)

    Reppa, Irene; Worth, E Rhian; Greville, W James; Saunders, Jo

    2013-06-01

    Information retrieval can cause forgetting for related but non-retrieved information. Such retrieval-induced forgetting (RIF) has been previously found for semantically and episodically related information. The current study used RIF to examine whether response effector and location are encoded explicitly in action memory. Participants learned unique touchscreen responses to ten novel objects. Correct actions to each object involved left-hand or right-hand pushing of one of four possible object buttons. After learning, participants practiced two of the ten object-specific sequences. Unpracticed actions could share hand only, button only, both hand and button, or neither hand nor button, with the practiced actions. Subsequent testing showed significant RIF (in retrieval accuracy and speed measures) for actions that shared hand only, button only, or both hand and button with the practiced action. The results have implications for understanding the representations mediating episodic action memory, and for the potential of RIF as a tool for elucidating feature-based representations in this and other domains.

  13. Introduction. Modelling natural action selection.

    Science.gov (United States)

    Prescott, Tony J; Bryson, Joanna J; Seth, Anil K

    2007-09-29

    Action selection is the task of resolving conflicts between competing behavioural alternatives. This theme issue is dedicated to advancing our understanding of the behavioural patterns and neural substrates supporting action selection in animals, including humans. The scope of problems investigated includes: (i) whether biological action selection is optimal (and, if so, what is optimized), (ii) the neural substrates for action selection in the vertebrate brain, (iii) the role of perceptual selection in decision-making, and (iv) the interaction of group and individual action selection. A second aim of this issue is to advance methodological practice with respect to modelling natural action section. A wide variety of computational modelling techniques are therefore employed ranging from formal mathematical approaches through to computational neuroscience, connectionism and agent-based modelling. The research described has broad implications for both natural and artificial sciences. One example, highlighted here, is its application to medical science where models of the neural substrates for action selection are contributing to the understanding of brain disorders such as Parkinson's disease, schizophrenia and attention deficit/hyperactivity disorder.

  14. Adaptive Neurons For Artificial Neural Networks

    Science.gov (United States)

    Tawel, Raoul

    1990-01-01

    Training time decreases dramatically. In improved mathematical model of neural-network processor, temperature of neurons (in addition to connection strengths, also called weights, of synapses) varied during supervised-learning phase of operation according to mathematical formalism and not heuristic rule. Evidence that biological neural networks also process information at neuronal level.

  15. Neural Events in the Reinforcement Contingency

    Science.gov (United States)

    Silva, Maria Teresa Araujo; Goncalves, Fabio Leyser; Garcia-Mijares, Miriam

    2007-01-01

    When neural events are analyzed as stimuli and responses, functional relations among them and among overt stimuli and responses can be unveiled. The integration of neuroscience and the experimental analysis of behavior is beginning to provide empirical evidence of involvement of neural events in the three-term contingency relating discriminative…

  16. Forecasting returns on a stock market using Artificial Neural Networks and GARCH family models: Evidence of stock market S&P 500

    Directory of Open Access Journals (Sweden)

    Nadhem Selmi

    2015-04-01

    Full Text Available In the area of financial stock market forecasting, many studies have focused on application of Artificial Neural Networks (ANNs. Due to its high rate of uncertainty and volatility, the stock markets returns forecasting by conventional methods became a difficult task. The ANNs is a relatively new and have been reported as good methods to predict financial stock market levels and can model flexible linear or non-linear relationship among variables. The aim of the study is to employ an ANN models to estimate and predict the dynamic volatility of the daily of S&P500 market returns. Results of ANN models will be compared with time series model using GARCH family models. The use of the novel model for conditional stock markets returns volatility can handle the vast amount of nonlinear data, simulate their relationship and give a moderate solution for the hard problem. The forecasts of stock index returns in the paper will be evaluated and compared, considering the MSE, RMSE and MAE forecasts statistic.

  17. Neural Networks

    Directory of Open Access Journals (Sweden)

    Schwindling Jerome

    2010-04-01

    Full Text Available This course presents an overview of the concepts of the neural networks and their aplication in the framework of High energy physics analyses. After a brief introduction on the concept of neural networks, the concept is explained in the frame of neuro-biology, introducing the concept of multi-layer perceptron, learning and their use as data classifer. The concept is then presented in a second part using in more details the mathematical approach focussing on typical use cases faced in particle physics. Finally, the last part presents the best way to use such statistical tools in view of event classifers, putting the emphasis on the setup of the multi-layer perceptron. The full article (15 p. corresponding to this lecture is written in french and is provided in the proceedings of the book SOS 2008.

  18. Generalisation of action sequences in RNNPB networks with mirror properties

    NARCIS (Netherlands)

    Cuijpers, R.H.; Stuijt, F.H.A.; Sprinkhuizen-Kuyper, I.G.

    2009-01-01

    The human mirror neuron system (MNS) is supposed to be involved in recognition of observed action sequences. However, it remains unclear how such a system could learn to recognise a large variety of action sequences. Here we investigated a neural network with mirror properties, the Recurrent Neural

  19. No evidence of neural adaptations following chronic unilateral isometric training of the intrinsic muscles of the hand: a randomized controlled study.

    Science.gov (United States)

    Manca, A; Ginatempo, F; Cabboi, M P; Mercante, B; Ortu, E; Dragone, D; De Natale, E R; Dvir, Z; Rothwell, J C; Deriu, Franca

    2016-10-01

    To test whether long-term cortical adaptations occur bilaterally following chronic unilateral training with a simple motor task. Participants (n = 34) were randomly allocated to a training or control groups. Only the former completed a 4-week maximal-intensity isometric training of the right first dorsal interosseus muscle through key pinching. Maximal strength was assessed bilaterally in four different movements progressively less similar to the training task: key, tip and tripod pinches, and handgrip. Transcranial magnetic stimulation was used to probe, in the left and right primary hand motor cortices, a number of standard tests of cortical excitability, including thresholds, intra-cortical inhibition and facilitation, transcallosal inhibition, and sensory-motor integration. Training increased strength in the trained hand, but only for the tasks specifically involving the trained muscle (key +8.5 %; p hand, i.e., a cross-education effect (key +6.4 %; p = 0.02; tip +4.7 %; p = 0.007). Despite these changes in strength, no significant variation was observed in any of the neurophysiological parameters describing cortico-spinal and intra-cortical excitability, inter-hemispheric inhibition, and cortical sensory-motor integration. A 4-week maximal-intensity unilateral training induced bilaterally spatial- and task-specific strength gains, which were not associated to direct or crossed cortical adaptations. The observed long-term stability of neurophysiological parameters might result from homeostatic plasticity phenomena, aimed at restoring the physiological inter-hemispheric balance of neural activity levels perturbed by the exercise. ClinicalTrials.gov identifier NCT02010398.

  20. Visual motion imagery neurofeedback based on the hMT+/V5 complex: evidence for a feedback-specific neural circuit involving neocortical and cerebellar regions

    Science.gov (United States)

    Banca, Paula; Sousa, Teresa; Catarina Duarte, Isabel; Castelo-Branco, Miguel

    2015-12-01

    Objective. Current approaches in neurofeedback/brain-computer interface research often focus on identifying, on a subject-by-subject basis, the neural regions that are best suited for self-driven modulation. It is known that the hMT+/V5 complex, an early visual cortical region, is recruited during explicit and implicit motion imagery, in addition to real motion perception. This study tests the feasibility of training healthy volunteers to regulate the level of activation in their hMT+/V5 complex using real-time fMRI neurofeedback and visual motion imagery strategies. Approach. We functionally localized the hMT+/V5 complex to further use as a target region for neurofeedback. An uniform strategy based on motion imagery was used to guide subjects to neuromodulate hMT+/V5. Main results. We found that 15/20 participants achieved successful neurofeedback. This modulation led to the recruitment of a specific network as further assessed by psychophysiological interaction analysis. This specific circuit, including hMT+/V5, putative V6 and medial cerebellum was activated for successful neurofeedback runs. The putamen and anterior insula were recruited for both successful and non-successful runs. Significance. Our findings indicate that hMT+/V5 is a region that can be modulated by focused imagery and that a specific cortico-cerebellar circuit is recruited during visual motion imagery leading to successful neurofeedback. These findings contribute to the debate on the relative potential of extrinsic (sensory) versus intrinsic (default-mode) brain regions in the clinical application of neurofeedback paradigms. This novel circuit might be a good target for future neurofeedback approaches that aim, for example, the training of focused attention in disorders such as ADHD.

  1. Neural adaptations to electrical stimulation strength training

    NARCIS (Netherlands)

    Hortobagyi, Tibor; Maffiuletti, Nicola A.

    2011-01-01

    This review provides evidence for the hypothesis that electrostimulation strength training (EST) increases the force of a maximal voluntary contraction (MVC) through neural adaptations in healthy skeletal muscle. Although electrical stimulation and voluntary effort activate muscle differently, there

  2. Sentential context modulates the involvement of the motor cortex in action language processing: an FMRI study.

    Science.gov (United States)

    Schuil, Karen D I; Smits, Marion; Zwaan, Rolf A

    2013-01-01

    Theories of embodied cognition propose that language comprehension is based on perceptual and motor processes. More specifically, it is hypothesized that neurons processing verbs describing bodily actions, and those that process the corresponding physical actions, fire simultaneously during action verb learning. Thus the concept and motor activation become strongly linked. According to this view, the language-induced activation of the neural substrates for action is automatic. By contrast, a weak view of embodied cognition proposes that activation of these motor regions is modulated by context. In recent studies it was found that action verbs in literal sentences activate the motor system, while mixed results were observed for action verbs in non-literal sentences. Thus, whether the recruitment of motor regions is automatic or context dependent remains a question. We investigated functional magnetic resonance imaging activation in response to non-literal and literal sentences including arm and leg related actions. The sentence structure was such that the action verb was the last word in the subordinate clause. Thus, the constraining context was presented well before the verb. Region of interest analyses showed that action verbs in literal context engage the motor regions to a greater extent than non-literal action verbs. There was no evidence for a semantic somatotopic organization of the motor cortex. Taken together, these results indicate that during comprehension, the degree to which motor regions are recruited is context dependent, supporting the weak view of embodied cognition.

  3. Organizational Actions of Metabolic Hormones

    OpenAIRE

    Bouret, Sebastien G.

    2013-01-01

    Brain development is a complex and dynamic process, and many environmental factors have been found to influence the normal development of neural pathways. Cumulative evidence suggests that metabolic hormones that regulate the hypothalamic circuits that control energy homeostasis function in much the same way that sex steroids act on sexually dimorphic circuits. For example, although the effects of the adipocyte-derived hormone leptin were originally thought to be limited to the neural control...

  4. Task-Irrelevant Expectation Violations in Sequential Manual Actions: Evidence for a "Check-after-Surprise" Mode of Visual Attention and Eye-Hand Decoupling.

    Science.gov (United States)

    Foerster, Rebecca M

    2016-01-01

    When performing sequential manual actions (e.g., cooking), visual information is prioritized according to the task determining where and when to attend, look, and act. In well-practiced sequential actions, long-term memory (LTM)-based expectations specify which action targets might be found where and when. We have previously demonstrated (Foerster and Schneider, 2015b) that violations of such expectations that are task-relevant (e.g., target location change) cause a regression from a memory-based mode of attentional selection to visual search. How might task-irrelevant expectation violations in such well-practiced sequential manual actions modify attentional selection? This question was investigated by a computerized version of the number-connection test. Participants clicked on nine spatially distributed numbered target circles in ascending order while eye movements were recorded as proxy for covert attention. Target's visual features and locations stayed constant for 65 prechange-trials, allowing practicing the manual action sequence. Consecutively, a task-irrelevant expectation violation occurred and stayed for 20 change-trials. Specifically, action target number 4 appeared in a different font. In 15 reversion-trials, number 4 returned to the original font. During the first task-irrelevant change trial, manual clicking was slower and eye scanpaths were larger and contained more fixations. The additional fixations were mainly checking fixations on the changed target while acting on later targets. Whereas the eyes repeatedly revisited the task-irrelevant change, cursor-paths remained completely unaffected. Effects lasted for 2-3 change trials and did not reappear during reversion. In conclusion, an unexpected task-irrelevant change on a task-defining feature of a well-practiced manual sequence leads to eye-hand decoupling and a "check-after-surprise" mode of attentional selection.

  5. Task-irrelevant expectation violations in sequential manual actions: Evidence for a “check-after-surprise” mode of visual attention and eye-hand decoupling

    Directory of Open Access Journals (Sweden)

    Rebecca Martina Foerster

    2016-11-01

    Full Text Available When performing sequential manual actions (e.g., cooking, visual information is prioritized according to the task determining where and when to attend, look, and act. In well-practiced sequential actions, long-term memory (LTM-based expectations specify which action targets might be found where and when. We have previously demonstrated (Foerster and Schneider, 2015b that violations of such expectations that are task-relevant (e.g., target location change cause a regression from a memory-based mode of attentional selection to visual search. How might task-irrelevant expectation violations in such well-practiced sequential manual actions modify attentional selection? This question was investigated by a computerized version of the number-connection test. Participants clicked on nine spatially-distributed numbered target circles in ascending order while eye movements were recorded as proxy for covert attention. Target’s visual features and locations stayed constant for 65 prechange-trials, allowing practicing the manual action sequence. Consecutively, a task-irrelevant expectation violation occurred and stayed for 20 change-trials. Specifically, action target number 4 appeared in a different font. In 15 reversion-trials, number 4 returned to the original font. During the first task-irrelevant change trial, manual clicking was slower and eye scanpaths were larger and contained more fixations. The additional fixations were mainly checking fixations on the changed target while acting on later targets. Whereas the eyes repeatedly revisited the task-irrelevant change, cursor-paths remained completely unaffected. Effects lasted for 2-3 change trials and did not reappear during reversion. In conclusion, an unexpected task-irrelevant change on a task-defining feature of a well-practiced manual sequence leads to eye-hand decoupling and a check-after-surprise mode of attentional selection.

  6. Regulation of the nascent brain vascular network by neural progenitors.

    Science.gov (United States)

    Santhosh, Devi; Huang, Zhen

    2015-11-01

    Neural progenitors are central players in the development of the brain neural circuitry. They not only produce the diverse neuronal and glial cell types in the brain, but also guide their migration in this process. Recent evidence indicates that neural progenitors also play a critical role in the development of the brain vascular network. At an early stage, neural progenitors have been found to facilitate the ingression of blood vessels from outside the neural tube, through VEGF and canonical Wnt signaling. Subsequently, neural progenitors directly communicate with endothelial cells to stabilize nascent brain vessels, in part through down-regulating Wnt pathway activity. Furthermore, neural progenitors promote nascent brain vessel integrity, through integrin αvβ8-dependent TGFβ signaling. In this review, we will discuss the evidence for, as well as questions that remain, regarding these novel roles of neural progenitors and the underlying mechanisms in their regulation of the nascent brain vascular network.

  7. Reducing the volume, exposure and negative impacts of advertising for foods high in fat, sugar and salt to children: A systematic review of the evidence from statutory and self-regulatory actions and educational measures.

    Science.gov (United States)

    Chambers, Stephanie A; Freeman, Ruth; Anderson, Annie S; MacGillivray, Steve

    2015-06-01

    To identify and review evidence on 1) the effectiveness of statutory and self-regulatory actions to reduce the volume, exposure or wider impact of advertising for foods high in fat, sugar and salt (HFSS) to children, and 2) the role of educational measures. A systematic review of three databases (Medline, CINAHL and PsycINFO) and grey literature was carried out. Relevant evidence included studies evaluating advertising bans and restrictions, advertising literacy programmes and parental communication styles. Relevant media included TV, internet, radio, magazines and newspaper advertising. No studies were excluded based on language or publication date. Forty-seven publications were included: 19 provided evidence for the results of statutory regulation, 25 for self-regulation, and six for educational approaches. Outcome measures varied in approach, quality and results. Findings suggested statutory regulation could reduce the volume of and children's exposure to advertising for foods HFSS, and had potential to impact more widely. Self-regulatory approaches showed varied results in reducing children's exposure. There was some limited support for educational measures. Consistency in measures from evaluations over time would assist the development and interpretation of the evidence base on successful actions and measures to reduce the volume, exposure and impact of advertising for foods HFSS to children. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. FGF Signaling Transforms Non-neural Ectoderm into Neural Crest

    OpenAIRE

    Yardley, Nathan; García-Castro, Martín I.

    2012-01-01

    The neural crest arises at the border between the neural plate and the adjacent non-neural ectoderm. It has been suggested that both neural and non-neural ectoderm can contribute to the neural crest. Several studies have examined the molecular mechanisms that regulate neural crest induction in neuralized tissues or the neural plate border. Here, using the chick as a model system, we address the molecular mechanisms by which non-neural ectoderm generates neural crest. We report that in respons...

  9. Action semantics modulate action prediction.

    Science.gov (United States)

    Springer, Anne; Prinz, Wolfgang

    2010-11-01

    Previous studies have demonstrated that action prediction involves an internal action simulation that runs time-locked to the real action. The present study replicates and extends these findings by indicating a real-time simulation process (Graf et al., 2007), which can be differentiated from a similarity-based evaluation of internal action representations. Moreover, results showed that action semantics modulate action prediction accuracy. The semantic effect was specified by the processing of action verbs and concrete nouns (Experiment 1) and, more specifically, by the dynamics described by action verbs (Experiment 2) and the speed described by the verbs (e.g., "to catch" vs. "to grasp" vs. "to stretch"; Experiment 3). These results propose a linkage between action simulation and action semantics as two yet unrelated domains, a view that coincides with a recent notion of a close link between motor processes and the understanding of action language.

  10. Remedial action and feedback processing in a time-estimation task: Evidence for a role of the rostral cingulate zone in behavioral adjustments without learning

    NARCIS (Netherlands)

    Veen, F.M. van der; Röder, C.H.; Mies, G.W.; Lugt, A. van der; Smits, M.

    2011-01-01

    The present study examined the role of the rostral cingulate zone (RCZ) in feedback processing, and especially focused on effects of modality of the feedback stimulus and remedial action. Participants performed a time-estimation task in which they had to estimate a 1-second interval. After the estim

  11. Optic ataxia as a model to investigate the role of the posterior parietal cortex in visually guided action: Evidence from studies of patient M.H.

    Directory of Open Access Journals (Sweden)

    Cristiana eCavina-Pratesi

    2013-07-01

    Full Text Available Optic ataxia is a neuropsychological disorder that affects the ability to interact with objects presented in the visual modality following either unilateral or bilateral lesions of the posterior parietal cortex (PPC. Patients with optic ataxia fail to reach accurately for objects, particularly when they are presented in peripheral vision. The present review will focus on a series of experiments performed on patient M.H. Following a lesion restricted largely to the left PPC, he developed mis-reaching behaviour when using his contralesional right arm for movements directed toward the contralesional (right visual half-field. Given the clear-cut specificity of this patient’s deficit, whereby reaching actions are essentially spared when executed toward his ipsilateral space or when using his left arm, M.H. provides a valuable experiment of nature for investigating the role of the PPC in performing different visually guided actions. In order to address this, we used kinematic measurement techniques to investigate M.H.’s reaching and grasping behaviour in various tasks. Our experiments support the idea that optic ataxia is highly function-specific: it affects a specific sub-category of visually guided actions (reaching but not grasping, regardless of their specific end goal (both reaching toward an object and reaching to avoid an obstacle; and finally, is independent of the limb used to perform the action (whether the arm or the leg. Critically, these results are congruent with recent functional MRI experiments in neurologically intact subjects which suggest that the PPC is organized in a function-specific, rather than effector-specific, manner with different sub-portions of its mantle devoted to guiding actions according to their specific end-goal (reaching, grasping or looking, rather than according to the effector used to perform them (leg, arm, hand or eyes.

  12. Lack of Evidence That Neural Empathic Responses Are Blunted in Excessive Users of Violent Video Games: An fMRI Study.

    Science.gov (United States)

    Szycik, Gregor R; Mohammadi, Bahram; Münte, Thomas F; Te Wildt, Bert T

    2017-01-01

    The use of violent video games has been often linked to increase of aggressive behavior. According to the General Aggression Model, one of the central mechanisms for this aggressiveness inducing impact is an emotional desensitization process resulting from long lasting repeated violent game playing. This desensitization should evidence itself in a lack of empathy. Recent research has focused primarily on acute, short term impact of violent media use but only little is known about long term effects. In this study 15 excessive users of violent games and control subjects matched for age and education viewed pictures depicting emotional and neutral situations with and without social interaction while fMRI activations were obtained. While the typical pattern of activations for empathy and theory of mind networks was seen, both groups showed no differences in brain responses. We interpret our results as evidence against the desensitization hypothesis and suggest that the impact of violent media on emotional processing may be rather acute and short-lived.

  13. Lack of Evidence That Neural Empathic Responses Are Blunted in Excessive Users of Violent Video Games: An fMRI Study

    Science.gov (United States)

    Szycik, Gregor R.; Mohammadi, Bahram; Münte, Thomas F.; te Wildt, Bert T.

    2017-01-01

    The use of violent video games has been often linked to increase of aggressive behavior. According to the General Aggression Model, one of the central mechanisms for this aggressiveness inducing impact is an emotional desensitization process resulting from long lasting repeated violent game playing. This desensitization should evidence itself in a lack of empathy. Recent research has focused primarily on acute, short term impact of violent media use but only little is known about long term effects. In this study 15 excessive users of violent games and control subjects matched for age and education viewed pictures depicting emotional and neutral situations with and without social interaction while fMRI activations were obtained. While the typical pattern of activations for empathy and theory of mind networks was seen, both groups showed no differences in brain responses. We interpret our results as evidence against the desensitization hypothesis and suggest that the impact of violent media on emotional processing may be rather acute and short-lived. PMID:28337156

  14. Integrating verbal and nonverbal communication in a dynamic neural field architecture for human-robot interaction

    Directory of Open Access Journals (Sweden)

    Estela Bicho

    2010-05-01

    Full Text Available How do humans coordinate their intentions, goals and motor behaviors when performing joint action tasks? Recent experimental evidence suggests that resonance processes in the observer's motor system are crucially involved in our ability to understand actions of others', to infer their goals and even to comprehend their action-related language. In this paper, we present a control architecture for human-robot collaboration that exploits this close perception-action linkage as a means to achieve more natural and efficient communication grounded in sensorimotor experiences. The architecture is formalized by a coupled system of dynamic neural fields representing a distributed network of neural populations that encode in their activation patterns goals, actions and shared task knowledge. We validate the verbal and non-verbal communication skills of the robot in a joint assembly task in which the human-robot team has to construct toy objects from their components. The experiments focus on the robot’s capacity to anticipate the user’s needs and to detect and communicate unexpected events that may occur during joint task execution.

  15. Rapid neural discrimination of communicative gestures.

    Science.gov (United States)

    Redcay, Elizabeth; Carlson, Thomas A

    2015-04-01

    Humans are biased toward social interaction. Behaviorally, this bias is evident in the rapid effects that self-relevant communicative signals have on attention and perceptual systems. The processing of communicative cues recruits a wide network of brain regions, including mentalizing systems. Relatively less work, however, has examined the timing of the processing of self-relevant communicative cues. In the present study, we used multivariate pattern analysis (decoding) approach to the analysis of magnetoencephalography (MEG) to study the processing dynamics of social-communicative actions. Twenty-four participants viewed images of a woman performing actions that varied on a continuum of communicative factors including self-relevance (to the participant) and emotional valence, while their brain activity was recorded using MEG. Controlling for low-level visual factors, we found early discrimination of emotional valence (70 ms) and self-relevant communicative signals (100 ms). These data offer neural support for the robust and rapid effects of self-relevant communicative cues on behavior.

  16. Cholinergic systems mediate action from movement to higher consciousness.

    Science.gov (United States)

    Woolf, Nancy J; Butcher, Larry L

    2011-08-10

    There is a fundamental link between cholinergic neurotransmitter function and overt and covert actions. Major cholinergic systems include peripheral motor neurons organizing skeletal muscle movements into overt behaviors and cholinergic neurons in the basal forebrain and mesopontine regions that mediate covert actions realized as states of consciousness, arousal, selective attention, perception, and memory. Cholinergic interneurons in the striatum appear to integrate conscious and unconscious actions. Neural network models involving cholinergic neurons, as well as neurons using other neurotransmitters, emphasize connective circuitry as being responsible for both motor programs and neural correlates of higher consciousness. This, however, is only a partial description. At a more fundamental level lie intracellular mechanisms involving the cytoskeleton, which are common to both muscle contraction and neuroplastic responses in targets of central cholinergic cells attendant with higher cognition. Acetylcholine, acting through nicotinic receptors, triggers interactions between cytoskeletal proteins in skeletal muscle cells, as has been long known. There is also evidence that acetylcholine released at central sites acts through muscarinic and nicotinic receptors to initiate responses in actin and microtubule proteins. These effects and their implications for cholinergic involvement in higher cognition are explored in this review.

  17. Neural Network Applications

    NARCIS (Netherlands)

    Vonk, E.; Jain, L.C.; Veelenturf, L.P.J.

    1995-01-01

    Artificial neural networks, also called neural networks, have been used successfully in many fields including engineering, science and business. This paper presents the implementation of several neural network simulators and their applications in character recognition and other engineering areas

  18. Simulated experiment evidences of the corrosion and reform actions of H2S to carbonate reservoirs: an example of Feixianguan Formation, east Sichuan

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The reservoir of Feixianguan Formation of the Lower Triassic in the Sichuan Basin is the deepest buried carbonate reservoir in China, with developed secondary corrosion holes, high quantities carbonate reservoir, maximum effective carbonate reservoir thickness. Also Feixianguan gas reservoir has the highest quantities of H2S. Research discovers that there are close relationships between the formation of reservoir and H2S. The mutual actions between acidity fluid and carbonate promoted the forming of secondary carbonate holes. Through the experiment of corrosion of the samples of Feixianguan carbonate reservoir in saturated aqueous solution of hydrogen sulfide, the porosity and permeability increased greatly, porosity increased 2% and permeability increased nearly two quantity degrees, also the density became light, which confirm the corrosion and reform actions of H2S to carbonate.

  19. New Evidence for the Mechanism of Action of a Type-2 Diabetes Drug Using a Magnetic Bead-Based Automated Biosensing Platform

    DEFF Research Database (Denmark)

    Uddin, Rokon; Nur-E-Habiba; Rena, Graham

    2017-01-01

    of metformin's blood-glucose lowering action. In this assay, cysteine-functionalized magnetic beadswere agglutinated in the presence of Cu due to cysteine's Cu-chelation property. Addition of clinically relevant doses of metformin resulted in disaggregation of Cu-bridged bead-clusters, whereas the effect...... of adding a closely related but blood-glucose neutral drug propanediimidamide (PDI) showed completely different responses to the clusters. The entire assay was integrated in an automated microfluidics platform with an advanced optical imaging unit by which we investigated these aggregation......-disaggregation phenomena in a reliable, automated, and user-friendly fashion with total assay time of 17 min requiring a sample (metformin/PDI) volume of 30 μL. The marked difference of Cu-binding action between the blood-glucose lowering drug metformin and its inactive analogue PDI thus suggests that metformin...

  20. Evidence for involvement of c-Src in the anti-apoptotic action of nitric oxide in serum-deprived RINm5F cells.

    Science.gov (United States)

    Tejedo, J R; Ramírez, R; Cahuana, G M; Rincón, P; Sobrino, F; Bedoya, F J

    2001-11-01

    The mechanism by which nitric oxide (NO) protects from apoptosis is a matter of debate. We have shown previously that phosphorylation of tyrosine residues participates in the protection from apoptosis in insulin-producing RINm5F cells (Inorg. Chem. Commun. 3 (2000) 32). Since NO has been reported to activate the tyrosine kinase c-Src and this kinase is involved in the activation of protein kinase G (PKG) in some cell systems, we aimed at studying the contribution of c-Src and PKG systems in anti-apoptotic actions of NO in serum-deprived RINm5F cells. Here we report that exposure of serum-deprived cells to 10 microM DETA/NO results in protection from degradation of the anti-apoptotic protein Bcl-2, together with a reduction of cytochrome c release from mitochondria and caspase-3 inhibition. Studies with the inhibitors ODQ and KT-5823 revealed that these actions are dependent on both activation of guanylate cyclase and PKG. DETA/NO was also able to induce autophosphorylation and activation c-Src protein both in vivo and in vitro and active c-Src was able to induce tyrosine phosphorylation of Bcl-2 in vitro. The c-Src kinase inhibitor PP1 abrogated the actions of DETA/NO on cGMP formation, PKG activation, caspase activation, cytochrome c release from mitochondria, and Bcl-2 phosphorylation and degradation in serum-deprived cells. We thus propose that activation of c-Src is an early step in the chain of events that signal cGMP-dependent anti-apoptotic actions of NO in mitocohondria.

  1. Determining the mode of action of anti-mycobacterial C17 diyne natural products using expression profiling: evidence for fatty acid biosynthesis inhibition

    OpenAIRE

    Li, Haoxin; Cowie, Andrew; JOHNSON, JOHN A.; Webster, Duncan; Martyniuk, Christopher J.; Gray, Christopher A.

    2016-01-01

    Background The treatment of microbial infections is becoming increasingly challenging because of limited therapeutic options and the growing number of pathogenic strains that are resistant to current antibiotics. There is an urgent need to identify molecules with novel modes of action to facilitate the development of new and more effective therapeutic agents. The anti-mycobacterial activity of the C17 diyne natural products falcarinol and panaxydol has been described previously; however, thei...

  2. Cocaine-induced cardiovascular effects: lack of evidence for a central nervous system site of action based on hemodynamic studies with cocaine methiodide.

    Science.gov (United States)

    Dickerson, L W; Rodak, D J; Kuhn, F E; Wahlstrom, S K; Tessel, R E; Visner, M S; Schaer, G L; Gillis, R A

    1999-01-01

    It has been suggested that cocaine acts directly in the brain to enhance central sympathetic outflow. However, some studies suggested that the cardiovascular effects of cocaine are related to a peripheral action. To characterize further the site of cocaine's cardiovascular effect, we compared the hemodynamic effects of cocaine (2 mg/kg, i.v. bolus) with those observed after administration of an equimolar dose (2.62 mg/kg, i.v. bolus) of cocaine methiodide, a quaternary derivative of cocaine that does not penetrate the blood-brain barrier, by using sufentanil-sedated dogs. Cocaine produced significant (p < 0.05) increases in heart rate (+37+/-11 beats/min), mean arterial pressure (+55+/-11 mm Hg), left ventricular end-diastolic pressure (+5.3+/-1.0 mm Hg), and cardiac output (+2.4+/-0.9 L/min). Cocaine methiodide produced increases in heart rate (+57+/-11 beats/min), mean arterial pressure (+45+/-11 mm Hg), left ventricular end-diastolic pressure (+3.4+/-1.0 mm Hg), and cardiac output (1.1+/-0.9 L/min), which were not significantly different from those observed with cocaine. Because opiate sedation potentially might have attenuated central sympathetic outflow, we further confirmed the qualitative similarity of the actions of cocaine and cocaine methiodide on heart rate and blood pressure in unsedated, conscious dogs. Our data suggest that the cardiovascular effects of cocaine result primarily from a peripheral site of action.

  3. Cross-resistance of an amsacrine-resistant human leukemia line to topoisomerase II reactive DNA intercalating agents. Evidence for two topoisomerase II directed drug actions

    Energy Technology Data Exchange (ETDEWEB)

    Zwelling, L.A.; Mayes, J.; Hinds, M.; Chan, D.; Altschuler, E.; Carroll, B.; Parker, E.; Deisseroth, K.; Radcliffe, A.; Seligman, M.; Li, Li; Farquhar, D. (Univ. of Texas M.D. Anderson Cancer Center, Houston (USA))

    1991-04-23

    HL-60/AMSA is a human leukemia cell line that is 50-100-fold more resistant than its drug-sensitive HL-60 parent line to the cytotoxic actions of the DNA intercalator amsacrine (m-AMSA). HL-60/AMSA topoisomerase II is also resistant to the inhibitory actions of m-AMSA. HL-60/AMSA cells and topoisomerase II are cross-resistant to anthracycline and ellipticine intercalators but relatively sensitive to the nonintercalating topoisomerase II reactive epipodophyllotoxin etoposide. The authors now demonstrate that HL-60/AMSA and its topoisomerase II are cross-resistant to the DNA intercalators mitoxantrone and amonafide, thus strongly indicating that HL-60/AMSA and its topoisomerase II are resistant to topoisomerase II reactive intercalators but not to nonintercalators. At high concentrations, mitoxantrone and amonafide were also found to inhibit their own, m-AMSA's, and etoposide's abilities to stabilize topoisomerase II-DNA complexes. These results suggest that the cytotoxicity of m-AMSA and etoposide is initiated primarily by the stabilization of the topoisomerase II-DNA complex. Other topoisomerase II reactive drugs may inhibit the enzyme at other steps in the topoisomerization cycle, particularly at elevated concentrations. Under these conditions, these latter drugs may not produce protein-associated DNA cleavage while still inhibiting topoisomerase II function as well as the actions of other topoisomerase II reactive drugs.

  4. Spin-mediated consciousness theory: possible roles of neural membrane nuclear spin ensembles and paramagnetic oxygen.

    Science.gov (United States)

    Hu, Huping; Wu, Maoxin

    2004-01-01

    A novel theory of consciousness is proposed in this paper. We postulate that consciousness is intrinsically connected to quantum spin since the latter is the origin of quantum effects in both Bohm and Hestenes quantum formulism and a fundamental quantum process associated with the structure of space-time. That is, spin is the "mind-pixel". The unity of mind is achieved by entanglement of the mind-pixels. Applying these ideas to the particular structures and dynamics of the brain, we theorize that human brain works as follows: through action potential modulated nuclear spin interactions and paramagnetic O2/NO driven activations, the nuclear spins inside neural membranes and proteins form various entangled quantum states some of which survive decoherence through quantum Zeno effects or in decoherence-free subspaces and then collapse contextually via irreversible and non-computable means producing consciousness and, in turn, the collective spin dynamics associated with said collapses have effects through spin chemistry on classical neural activities thus influencing the neural networks of the brain. Our proposal calls for extension of associative encoding of neural memories to the dynamical structures of neural membranes and proteins. Thus, according our theory, the nuclear spin ensembles are the "mind-screen" with nuclear spins as its pixels, the neural membranes and proteins are the mind-screen and memory matrices, and the biologically available paramagnetic species such as O2 and NO are pixel-activating agents. Together, they form the neural substrates of consciousness. We also present supporting evidence and make important predictions. We stress that our theory is experimentally verifiable with present technologies. Further, experimental realizations of intra-/inter-molecular nuclear spin coherence and entanglement, macroscopic entanglement of spin ensembles and NMR quantum computation, all in room temperatures, strongly suggest the possibility of a spin

  5. The minimalist grammar of action.

    Science.gov (United States)

    Pastra, Katerina; Aloimonos, Yiannis

    2012-01-12

    Language and action have been found to share a common neural basis and in particular a common 'syntax', an analogous hierarchical and compositional organization. While language structure analysis has led to the formulation of different grammatical formalisms and associated discriminative or generative computational models, the structure of action is still elusive and so are the related computational models. However, structuring action has important implications on action learning and generalization, in both human cognition research and computation. In this study, we present a biologically inspired generative grammar of action, which employs the structure-building operations and principles of Chomsky's Minimalist Programme as a reference model. In this grammar, action terminals combine hierarchically into temporal sequences of actions of increasing complexity; the actions are bound with the involved tools and affected objects and are governed by certain goals. We show, how the tool role and the affected-object role of an entity within an action drives the derivation of the action syntax in this grammar and controls recursion, merge and move, the latter being mechanisms that manifest themselves not only in human language, but in human action too.

  6. Turning knowledge into action at the point-of-care: the collective experience of nurses facilitating the implementation of evidence-based practice.

    Science.gov (United States)

    Dogherty, Elizabeth J; Harrison, Margaret B; Graham, Ian D; Vandyk, Amanda Digel; Keeping-Burke, Lisa

    2013-08-01

    Facilitation is considered a way of enabling clinicians to implement evidence into practice by problem solving and providing support. Practice development is a well-established movement in the United Kingdom that incorporates the use of facilitators, but in Canada, the role is more obtuse. Few investigations have observed the process of facilitation as described by individuals experienced in guideline implementation in North America. To describe the tacit knowledge regarding facilitation embedded in the experiences of nurses implementing evidence into practice. Twenty nurses from across Canada were purposively selected to attend an interactive knowledge translation symposium to examine what has worked and what has not in implementing evidence in practice. This study is an additional in-depth analysis of data collected at the symposium that focuses on facilitation as an intervention to enhance evidence uptake. Critical incident technique was used to elicit examples to examine the nurses' facilitation experiences. Participants shared their experiences with one another and completed initial data analysis and coding collaboratively. The data were further thematically analyzed using the qualitative inductive approach of constant comparison. A number of factors emerged at various levels associated with the successes and failures of participants' efforts to facilitate evidence-based practice. Successful implementation related to: (a) focus on a priority issue, (b) relevant evidence, (c) development of strategic partnerships, (d) the use of multiple strategies to effect change, and (e) facilitator characteristics and approach. Negative factors influencing the process were: (a) poor engagement or ownership, (b) resource deficits, (c) conflict, (d) contextual issues, and (e) lack of evaluation and sustainability. Factors at the individual, environmental, organizational, and cultural level influence facilitation of evidence-based practice in real situations at the point

  7. Neural Correlates of Task-Irrelevant First and Second Language Emotion Words — Evidence from the Face-Word Stroop Task

    Directory of Open Access Journals (Sweden)

    Lin Fan

    2016-11-01

    Full Text Available Emotionally valenced words have thus far not been empirically examined in a bilingual population with the emotional face-word Stroop paradigm. Chinese-English bilinguals were asked to identify the facial expressions of emotion with their first (L1 or second (L2 language task-irrelevant emotion words superimposed on the face pictures. We attempted to examine how the emotional content of words modulates behavioral performance and cerebral functioning in the bilinguals’ two languages. The results indicated that there were significant congruency effects for both L1 and L2 emotion words, and that identifiable differences in the magnitude of Stroop effect between the two languages were also observed, suggesting L1 is more capable of activating the emotional response to word stimuli. For event-related potentials (ERPs data, an N350-550 effect was observed only in L1 task with greater negativity for incongruent than congruent trials. The size of N350-550 effect differed across languages, whereas no identifiable language distinction was observed in the effect of conflict slow potential (conflict SP. Finally, more pronounced negative amplitude at 230-330 ms was observed in L1 than in L2, but only for incongruent trials. This negativity, likened to an orthographic decoding N250, may reflect the extent of attention to emotion word processing at word-form level, while N350-550 reflects a complicated set of processes in the conflict processing. Overall, the face-word congruency effect has reflected identifiable language distinction at 230-330 and 350-550 ms, which provides supporting evidence for the theoretical proposals assuming attenuated emotionality of L2 processing.

  8. Neural Correlates of Task-Irrelevant First and Second Language Emotion Words – Evidence from the Emotional Face–Word Stroop Task

    Science.gov (United States)

    Fan, Lin; Xu, Qiang; Wang, Xiaoxi; Zhang, Feng; Yang, Yaping; Liu, Xiaoping

    2016-01-01

    Emotionally valenced words have thus far not been empirically examined in a bilingual population with the emotional face–word Stroop paradigm. Chinese-English bilinguals were asked to identify the facial expressions of emotion with their first (L1) or second (L2) language task-irrelevant emotion words superimposed on the face pictures. We attempted to examine how the emotional content of words modulated behavioral performance and cerebral functioning in the bilinguals’ two languages. The results indicated that there were significant congruency effects for both L1 and L2 emotion words, and that identifiable differences in the magnitude of the Stroop effect between the two languages were also observed, suggesting L1 is more capable of activating the emotional response to word stimuli. For event-related potentials data, an N350–550 effect was observed only in the L1 task with greater negativity for incongruent than congruent trials. The size of the N350–550 effect differed across languages, whereas no identifiable language distinction was observed in the effect of conflict slow potential (conflict SP). Finally, more pronounced negative amplitude at 230–330 ms was observed in L1 than in L2, but only for incongruent trials. This negativity, likened to an orthographic decoding N250, may reflect the extent of attention to emotion word processing at word-form level, while the N350–550 reflects a complicated set of processes in the conflict processing. Overall, the face–word congruency effect has reflected identifiable language distinction at 230–330 and 350-550 ms, which provides supporting evidence for the theoretical proposals assuming attenuated emotionality of L2 processing. PMID:27847485

  9. Co-lateralized bilingual mechanisms for reading in single and dual language contexts: evidence from visual half-field processing of action words in proficient bilinguals

    Directory of Open Access Journals (Sweden)

    Marlena eKrefta

    2015-08-01

    Full Text Available When reading, proficient bilinguals seem to engage the same cognitive circuits regardless of the language in use. Yet, whether or not such ‘bilingual’ mechanisms would be lateralized in the same way in distinct – single or dual – language contexts is a question for debate. To fill this gap, we tested 18 highly proficient Polish (L1 – English (L2 childhood bilinguals whose task was to read aloud one of the two laterally presented action verbs, one stimulus per visual half field. While in the single-language blocks only L1 or L2 words were shown, in the subsequent mixed-language blocks words from both languages were concurrently displayed. All stimuli were presented for 217 ms followed by masks in which letters were replaced with hash marks. Since in non-simultaneous bilinguals the control of language, skilled actions (including reading, and representations of action concepts are typically left lateralized, the vast majority of our participants showed the expected, significant right visual field advantage for L1 and L2, both for accuracy and response times. The observed effects were nevertheless associated with substantial variability in the strength of the lateralization of the mechanisms involved. Moreover, although it could be predicted that participants’ performance should be better in a single-language context, accuracy was significantly higher and response times were significantly shorter in a dual-language context, irrespective of the language tested. Finally, for both accuracy and response times, there were significant positive correlations between the laterality indices (LIs of both languages independent of the context, with a significantly greater left-sided advantage for L1 vs. L2 in the mixed-language blocks, based on LIs calculated for response times. Thus, despite similar representations of the two languages in the bilingual brain, these results also point to the functional separation of L1 and L2 in the dual

  10. Comparison of Monetary Policy Actions and Central Bank Communication on Tackling Asset Price Bubbles—Evidence from China’s Stock Market

    Science.gov (United States)

    Sun, Ou; Liu, Zhixin

    2016-01-01

    We examine the different effects of monetary policy actions and central bank communication on China’s stock market bubbles with a Time-varying Parameter SVAR model. We find that with negative responses of fundamental component and positive responses of bubble component of asset prices, contractionary monetary policy induces the observed stock prices to rise during periods of large bubbles. By contrast, central bank communication acts on the market through expectation guidance and has more significant effects on stock prices in the long run, which implies that central bank communication be used as an effective long-term instrument for the central bank’s policymaking. PMID:27851796

  11. Using fuzzy logic to integrate neural networks and knowledge-based systems

    Science.gov (United States)

    Yen, John

    1991-01-01

    Outlined here is a novel hybrid architecture that uses fuzzy logic to integrate neural networks and knowledge-based systems. The author's approach offers important synergistic benefits to neural nets, approximate reasoning, and symbolic processing. Fuzzy inference rules extend symbolic systems with approximate reasoning capabilities, which are used for integrating and interpreting the outputs of neural networks. The symbolic system captures meta-level information about neural networks and defines its interaction with neural networks through a set of control tasks. Fuzzy action rules provide a robust mechanism for recognizing the situations in which neural networks require certain control actions. The neural nets, on the other hand, offer flexible classification and adaptive learning capabilities, which are crucial for dynamic and noisy environments. By combining neural nets and symbolic systems at their system levels through the use of fuzzy logic, the author's approach alleviates current difficulties in reconciling differences between low-level data processing mechanisms of neural nets and artificial intelligence systems.

  12. Simposio sobre Educacion de Ninas: Evidencias, Temas, Acciones. Actas de sesiones. (Symposium on Girls Education: Evidence, Issues, Actions. Proceedings). (Washington, DC, May 17-18, 2000).

    Science.gov (United States)

    Agency for International Development (IDCA), Washington, DC.

    This symposium highlighted core issues of controversy in girls' education and developed implications for policy and practice. Its evidence-based discussion forum encouraged dialogue, debate, and increased interaction and developed partnerships among academic institutions, nongovernmental organizations, multilateral development agencies, and other…

  13. Estimation of network structure for signal propagations by the analysis of multichannel action potentials in cultured neural networks; Ta channel katsudo den`i kaiseki ni yoru baiyo shinkei kairomonai kofun denpa keiro no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Konno, N.; Fukami, T.; Shiina, T. [University of Tsukuba, Tsukuba (Japan); Jinbo, Y. [Nippon Telegraph and Telephone Corp., Tokyo (Japan)

    1998-07-01

    We have fabricated a 64 embedded microelectrode-array substrate using semiconductor technology to investigate the biological signal processing in brain by using cultured neural networks of fetal rat neocortex in vitro. We analyzed temporal and spatial neural networks patterns cultured on electrode-array substrate and attempted to examine the network structure constituted by neurons and the propagating patterns of electrical activity induced by the electric stimulus. In the experiments, each microelectrode size was 30 {mu}m squared and 150{mu} m spaced. For stimulation, one of the electrodes was selected and current pulses were applied through an isolated circuit. After the network was cultured in about 50 days, responses of neurons to electric stimulus were monitored extracellularly through 64-channel electrode array. Data recorded at each electrode consist of several spike trains generated by different cells. Therefore, these trains were separated by using wavelet transform and template matching for each electrode. We referred the temporal patterns of generated spikes for each electrode to as `spike sequences`. Next, we compared With the spike sequences among multichannel data and visualized the Cultured neural networks structure by identifying the directions of propagations and cell connections. 15 refs., 9 figs.

  14. From action to language: comparative perspectives on primate tool use, gesture and the evolution of human language.

    Science.gov (United States)

    Steele, James; Ferrari, Pier Francesco; Fogassi, Leonardo

    2012-01-12

    The papers in this Special Issue examine tool use and manual gestures in primates as a window on the evolution of the human capacity for language. Neurophysiological research has supported the hypothesis of a close association between some aspects of human action organization and of language representation, in both phonology and semantics. Tool use provides an excellent experimental context to investigate analogies between action organization and linguistic syntax. Contributors report and contextualize experimental evidence from monkeys, great apes, humans and fossil hominins, and consider the nature and the extent of overlaps between the neural representations of tool use, manual gestures and linguistic processes.

  15. Action video game training reduces the Simon Effect.

    Science.gov (United States)

    Hutchinson, Claire V; Barrett, Doug J K; Nitka, Aleksander; Raynes, Kerry

    2016-04-01

    A number of studies have shown that training on action video games improves various aspects of visual cognition including selective attention and inhibitory control. Here, we demonstrate that action video game play can also reduce the Simon Effect, and, hence, may have the potential to improve response selection during the planning and execution of goal-directed action. Non-game-players were randomly assigned to one of four groups; two trained on a first-person-shooter game (Call of Duty) on either Microsoft Xbox or Nintendo DS, one trained on a visual training game for Nintendo DS, and a control group who received no training. Response times were used to contrast performance before and after training on a behavioral assay designed to manipulate stimulus-response compatibility (the Simon Task). The results revealed significantly faster response times and a reduced cost of stimulus-response incompatibility in the groups trained on the first-person-shooter game. No benefit of training was observed in the control group or the group trained on the visual training game. These findings are consistent with previous evidence that action game play elicits plastic changes in the neural circuits that serve attentional control, and suggest training may facilitate goal-directed action by improving players' ability to resolve conflict during response selection and execution.

  16. Action physics

    Science.gov (United States)

    McGinness, Lachlan P.; Savage, C. M.

    2016-09-01

    More than a decade ago, Edwin Taylor issued a "call to action" that presented the case for basing introductory university mechanics teaching around the principle of stationary action [E. F. Taylor, Am. J. Phys. 71, 423-425 (2003)]. We report on our response to that call in the form of an investigation of the teaching and learning of the stationary action formulation of physics in a first-year university course. Our action physics instruction proceeded from the many-paths approach to quantum physics to ray optics, classical mechanics, and relativity. Despite the challenges presented by action physics, students reported it to be accessible, interesting, motivational, and valuable.

  17. Neural crest contributions to the lamprey head

    Science.gov (United States)

    McCauley, David W.; Bronner-Fraser, Marianne

    2003-01-01

    The neural crest is a vertebrate-specific cell population that contributes to the facial skeleton and other derivatives. We have performed focal DiI injection into the cranial neural tube of the developing lamprey in order to follow the migratory pathways of discrete groups of cells from origin to destination and to compare neural crest migratory pathways in a basal vertebrate to those of gnathostomes. The results show that the general pathways of cranial neural crest migration are conserved throughout the vertebrates, with cells migrating in streams analogous to the mandibular and hyoid streams. Caudal branchial neural crest cells migrate ventrally as a sheet of cells from the hindbrain and super-pharyngeal region of the neural tube and form a cylinder surrounding a core of mesoderm in each pharyngeal arch, similar to that seen in zebrafish and axolotl. In addition to these similarities, we also uncovered important differences. Migration into the presumptive caudal branchial arches of the lamprey involves both rostral and caudal movements of neural crest cells that have not been described in gnathostomes, suggesting that barriers that constrain rostrocaudal movement of cranial neural crest cells may have arisen after the agnathan/gnathostome split. Accordingly, neural crest cells from a single axial level contributed to multiple arches and there was extensive mixing between populations. There was no apparent filling of neural crest derivatives in a ventral-to-dorsal order, as has been observed in higher vertebrates, nor did we find evidence of a neural crest contribution to cranial sensory ganglia. These results suggest that migratory constraints and additional neural crest derivatives arose later in gnathostome evolution.

  18. Incentive memory: evidence the basolateral amygdala encodes and the insular cortex retrieves outcome values to guide choice between goal-directed actions.

    Science.gov (United States)

    Parkes, Shauna L; Balleine, Bernard W

    2013-05-15

    Choice between goal-directed actions is determined by the relative value of their consequences. Such values are encoded during incentive learning and later retrieved to guide performance. Although the basolateral amygdala (BLA) and the gustatory region of insular cortex (IC) have been implicated in these processes, their relative contribution is still a matter of debate. Here we assessed whether these structures interact during incentive learning and retrieval to guide choice. In these experiments, rats were trained on two actions for distinct outcomes after which one of the two outcomes was devalued by specific satiety immediately before a choice extinction test. We first confirmed that, relative to appropriate controls, outcome devaluation recruited both the BLA and IC based on activation of the immediate early gene Arc; however, we found that infusion of the NMDAr antagonist ifenprodil into the BLA only abolished outcome devaluation when given before devaluation. In contrast, ifenprodil infusion into the IC was effective whether made before devaluation or test. We hypothesized that the BLA encodes and the IC retrieves incentive value for choice and, to test this, developed a novel sequential disconnection procedure. Blocking NMDAr activation unilaterally in the BLA before devaluation and then contralaterally in the IC before test abolished selective devaluation. In contrast, reversing the order of these infusions left devaluation intact. These results confirm that the BLA and IC form a circuit mediating the encoding and retrieval of outcome values, with the BLA encoding and the IC retrieving such values to guide choice.

  19. Changes of right-hemispheric activation after constraint-induced, intensive language action therapy in chronic aphasia: fMRI evidence from auditory semantic processing

    Directory of Open Access Journals (Sweden)

    Bettina eMohr

    2014-11-01

    Full Text Available The role of the two hemispheres in the neurorehabilitation of language is still under dispute. This study explored the changes in language-evoked brain activation over a two-week treatment interval with intensive constraint induced aphasia therapy (CIAT, which is also called intensive language action therapy (ILAT. Functional magnetic resonance imaging (fMRI was used to assess brain activation in perilesional left hemispheric and in homotopic right hemispheric areas during passive listening to high and low-ambiguity sentences and non-speech control stimuli in chronic non-fluent aphasia patients. All patients demonstrated significant clinical improvements of language functions after therapy. In an event-related fMRI experiment, a significant increase of BOLD signals was manifest in right inferior frontal and temporal areas. This activation increase was stronger for highly ambiguous sentences than for unambiguous ones. These results suggest that the known language improvements brought about by intensive constraint-induced language action therapy at least in part relies on circuits within the right-hemispheric homologues of left-perisylvian language areas, which are most strongly activated in the processing of semantically complex language.

  20. Changes of right-hemispheric activation after constraint-induced, intensive language action therapy in chronic aphasia: fMRI evidence from auditory semantic processing.

    Science.gov (United States)

    Mohr, Bettina; Difrancesco, Stephanie; Harrington, Karen; Evans, Samuel; Pulvermüller, Friedemann

    2014-01-01

    The role of the two hemispheres in the neurorehabilitation of language is still under dispute. This study explored the changes in language-evoked brain activation over a 2-week treatment interval with intensive constraint induced aphasia therapy (CIAT), which is also called intensive language action therapy (ILAT). Functional magnetic resonance imaging (fMRI) was used to assess brain activation in perilesional left hemispheric and in homotopic right hemispheric areas during passive listening to high and low-ambiguity sentences and non-speech control stimuli in chronic non-fluent aphasia patients. All patients demonstrated significant clinical improvements of language functions after therapy. In an event-related fMRI experiment, a significant increase of BOLD signal was manifest in right inferior frontal and temporal areas. This activation increase was stronger for highly ambiguous sentences than for unambiguous ones. These results suggest that the known language improvements brought about by intensive constraint-induced language action therapy at least in part relies on circuits within the right-hemispheric homologs of left-perisylvian language areas, which are most strongly activated in the processing of semantically complex language.

  1. Complementary Actions

    Directory of Open Access Journals (Sweden)

    Luisa eSartori

    2015-05-01

    Full Text Available Complementary colors are color pairs which, when combined in the right proportions, produce white or black. Complementary actions refer here to forms of social interaction wherein individuals adapt their joint actions according to a common aim. Notably, complementary actions are incongruent actions. But being incongruent is not sufficient to be complementary (i.e., to complete the action of another person. Successful complementary interactions are founded on the abilities: (i to simulate another person’s movements, (ii to predict another person’s future action/s, (iii to produce an appropriate incongruent response which differ, while interacting, with observed ones, and (iv to complete the social interaction by integrating the predicted effects of one’s own action with those of another person. This definition clearly alludes to the functional importance of complementary actions in the perception–action cycle and prompts us to scrutinize what is taking place behind the scenes. Preliminary data on this topic have been provided by recent cutting-edge studies utilizing different research methods. This mini-review aims to provide an up-to-date overview of the processes and the specific activations underlying complementary actions.

  2. Neural substrates of semantic memory.

    Science.gov (United States)

    Hart, John; Anand, Raksha; Zoccoli, Sandra; Maguire, Mandy; Gamino, Jacque; Tillman, Gail; King, Richard; Kraut, Michael A

    2007-09-01

    Semantic memory is described as the storage of knowledge, concepts, and information that is common and relatively consistent across individuals (e.g., memory of what is a cup). These memories are stored in multiple sensorimotor modalities and cognitive systems throughout the brain (e.g., how a cup is held and manipulated, the texture of a cup's surface, its shape, its function, that is related to beverages such as coffee, and so on). Our ability to engage in purposeful interactions with our environment is dependent on the ability to understand the meaning and significance of the objects and actions around us that are stored in semantic memory. Theories of the neural basis of the semantic memory of objects have produced sophisticated models that have incorporated to varying degrees the results of cognitive and neural investigations. The models are grouped into those that are (1) cognitive models, where the neural data are used to reveal dissociations in semantic memory after a brain lesion occurs; (2) models that incorporate both cognitive and neuroanatomical information; and (3) models that use cognitive, neuroanatomic, and neurophysiological data. This review highlights the advances and issues that have emerged from these models and points to future directions that provide opportunities to extend these models. The models of object memory generally describe how category and/or feature representations encode for object memory, and the semantic operations engaged in object processing. The incorporation of data derived from multiple modalities of investigation can lead to detailed neural specifications of semantic memory organization. The addition of neurophysiological data can potentially provide further elaboration of models to include semantic neural mechanisms. Future directions should incorporate available and newly developed techniques to better inform the neural underpinning of semantic memory models.

  3. Representation of actions in rats: the role of cerebellum in learning spatial performances by observation.

    Science.gov (United States)

    Leggio, M G; Molinari, M; Neri, P; Graziano, A; Mandolesi, L; Petrosini, L

    2000-02-29

    Experimental evidence demonstrates that cerebellar networks are involved in spatial learning, controlling the acquisition of exploration strategies without blocking motor execution of the task. Action learning by observation has been considered somehow related to motor physiology, because it provides a way of learning performances that is almost as effective as the actual execution of actions. Neuroimaging studies demonstrate that observation of movements performed by others, imagination of actions, and actual execution of motor performances share common neural substrates and that the cerebellum is among these shared areas. The present paper analyzes the effects of observation in learning a spatial task, focusing on the cerebellar role in learning a spatial ability through observation. We allowed normal rats to observe 200 Morris water maze trials performed by companion rats. After this observation training, "observer" rats underwent a hemicerebellectomy and then were tested in the Morris water maze. In spite of the cerebellar lesion, they displayed no spatial defects, exhibiting exploration abilities comparable to controls. When the cerebellar lesion preceded observation training, a complete lack of spatial observational learning was observed. Thus, as demonstrated already for the acquisition of spatial procedures through actual execution, cerebellar circuits appear to play a key role in the acquisition of spatial procedures also through observation. In conclusion, the present results provide strong support for a common neural basis in the observation of actions that are to be reproduced as well as in the actual production of the same actions.

  4. Introduction to spiking neural networks: Information processing, learning and applications.

    Science.gov (United States)

    Ponulak, Filip; Kasinski, Andrzej

    2011-01-01

    The concept that neural information is encoded in the firing rate of neurons has been the dominant paradigm in neurobiology for many years. This paradigm has also been adopted by the theory of artificial neural networks. Recent physiological experiments demonstrate, however, that in many parts of the nervous system, neural code is founded on the timing of individual action potentials. This finding has given rise to the emergence of a new class of neural models, called spiking neural networks. In this paper we summarize basic properties of spiking neurons and spiking networks. Our focus is, specifically, on models of spike-based information coding, synaptic plasticity and learning. We also survey real-life applications of spiking models. The paper is meant to be an introduction to spiking neural networks for scientists from various disciplines interested in spike-based neural processing.

  5. Immune modulation of learning, memory, neural plasticity and neurogenesis.

    Science.gov (United States)

    Yirmiya, Raz; Goshen, Inbal

    2011-02-01

    Over the past two decades it became evident that the immune system plays a central role in modulating learning, memory and neural plasticity. Under normal quiescent conditions, immune mechanisms are activated by environmental/psychological stimuli and positively regulate the remodeling of neural circuits, promoting memory consolidation, hippocampal long-term potentiation (LTP) and neurogenesis. These beneficial effects of the immune system are mediated by complex interactions among brain cells with immune functions (particularly microglia and astrocytes), peripheral immune cells (particularly T cells and macrophages), neurons, and neural precursor cells. These interactions involve the responsiveness of non-neuronal cells to classical neurotransmitters (e.g., glutamate and monoamines) and hormones (e.g., glucocorticoids), as well as the secretion and responsiveness of neurons and glia to low levels of inflammatory cytokines, such as interleukin (IL)-1, IL-6, and TNFα, as well as other mediators, such as prostaglandins and neurotrophins. In conditions under which the immune system is strongly activated by infection or injury, as well as by severe or chronic stressful conditions, glia and other brain immune cells change their morphology and functioning and secrete high levels of pro-inflammatory cytokines and prostaglandins. The production of these inflammatory mediators disrupts the delicate balance needed for the neurophysiological actions of immune processes and produces direct detrimental effects on memory, neural plasticity and neurogenesis. These effects are mediated by inflammation-induced neuronal hyper-excitability and adrenocortical stimulation, followed by reduced production of neurotrophins and other plasticity-related molecules, facilitating many forms of neuropathology associated with normal aging as well as neurodegenerative and neuropsychiatric diseases. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Serotonin, neural markers and memory

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    Alfredo eMeneses

    2015-07-01

    Full Text Available Diverse neuropsychiatric disorders present dysfunctional memory and no effective treatment exits for them; likely as result of the absence of neural markers associated to memory. Neurotransmitter systems and signaling pathways have been implicated in memory and dysfunctional memory; however, their role is poorly understood. Hence, neural markers and cerebral functions and dysfunctions are revised. To our knowledge no previous systematic works have been published addressing these issues. The interactions among behavioral tasks, control groups and molecular changes and/or pharmacological effects are mentioned. Neurotransmitter receptors and signaling pathways, during normal and abnormally functioning memory with an emphasis on the behavioral aspects of memory are revised. With focus on serotonin, since as it is a well characterized neurotransmitter, with multiple pharmacological tools, and well characterized downstream signaling in mammals’ species. 5-HT1A, 5-HT4, 5-HT5, 5-HT6 and 5-HT7 receptors as well as SERT (serotonin transporter seem to be useful neural markers and/or therapeutic targets. Certainly, if the mentioned evidence is replicated, then the translatability from preclinical and clinical studies to neural changes might be confirmed. Hypothesis and theories might provide appropriate limits and perspectives of evidence

  7. Serotonin, neural markers, and memory.

    Science.gov (United States)

    Meneses, Alfredo

    2015-01-01

    Diverse neuropsychiatric disorders present dysfunctional memory and no effective treatment exits for them; likely as result of the absence of neural markers associated to memory. Neurotransmitter systems and signaling pathways have been implicated in memory and dysfunctional memory; however, their role is poorly understood. Hence, neural markers and cerebral functions and dysfunctions are revised. To our knowledge no previous systematic works have been published addressing these issues. The interactions among behavioral tasks, control groups and molecular changes and/or pharmacological effects are mentioned. Neurotransmitter receptors and signaling pathways, during normal and abnormally functioning memory with an emphasis on the behavioral aspects of memory are revised. With focus on serotonin, since as it is a well characterized neurotransmitter, with multiple pharmacological tools, and well characterized downstream signaling in mammals' species. 5-HT1A, 5-HT4, 5-HT5, 5-HT6, and 5-HT7 receptors as well as SERT (serotonin transporter) seem to be useful neural markers and/or therapeutic targets. Certainly, if the mentioned evidence is replicated, then the translatability from preclinical and clinical studies to neural changes might be confirmed. Hypothesis and theories might provide appropriate limits and perspectives of evidence.

  8. Neural Induction, Neural Fate Stabilization, and Neural Stem Cells

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    Sally A. Moody

    2002-01-01

    Full Text Available The promise of stem cell therapy is expected to greatly benefit the treatment of neurodegenerative diseases. An underlying biological reason for the progressive functional losses associated with these diseases is the extremely low natural rate of self-repair in the nervous system. Although the mature CNS harbors a limited number of self-renewing stem cells, these make a significant contribution to only a few areas of brain. Therefore, it is particularly important to understand how to manipulate embryonic stem cells and adult neural stem cells so their descendants can repopulate and functionally repair damaged brain regions. A large knowledge base has been gathered about the normal processes of neural development. The time has come for this information to be applied to the problems of obtaining sufficient, neurally committed stem cells for clinical use. In this article we review the process of neural induction, by which the embryonic ectodermal cells are directed to form the neural plate, and the process of neural�fate stabilization, by which neural plate cells expand in number and consolidate their neural fate. We will present the current knowledge of the transcription factors and signaling molecules that are known to be involved in these processes. We will discuss how these factors may be relevant to manipulating embryonic stem cells to express a neural fate and to produce large numbers of neurally committed, yet undifferentiated, stem cells for transplantation therapies.

  9. Sentential context modulates the involvement of the motor cortex in action language processing: An fMRI study

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    Karen D.I. Schuil

    2013-04-01

    Full Text Available Theories of embodied cognition propose that language comprehension is based on perceptual and motor processes. More specifically, it is hypothesized that neurons processing verbs describing bodily actions, and those that process the corresponding physical actions, fire simultaneously during action verb learning. Thus the concept and motor activation become strongly linked. According to this view, the language-induced activation of the neural substrates for action is automatic. By contrast, a moderate view of embodied cognition proposes that activation of these motor regions is modulated by context. In recent studies it was found that action verbs in literal sentences activate the motor system, while mixed results were observed for action verbs in nonliteral sentences. Thus, whether the recruitment of motor regions is automatic or context dependent remains a question. We investigated functional magnetic resonance imaging activation in response to nonliteral and literal sentences including arm and leg related actions. The sentence structure was such that the action verb was the last word in the subordinate clause. Thus, the constraining context was presented well before the verb. Region of interest analyses showed that action verbs in literal context engage the motor regions to a greater extent than nonliteral action verbs. There was no evidence for a semantic somatotopic organization of the motor cortex. Taken together, these results indicate that during comprehension, the degree to which motor regions are recruited is context dependent, supporting the weak view of embodied cognition.

  10. Action representation: crosstalk between semantics and pragmatics.

    Science.gov (United States)

    Prinz, Wolfgang

    2014-03-01

    Marc Jeannerod pioneered a representational approach to movement and action. In his approach, motor representations provide both, declarative knowledge about action and procedural knowledge for action (action semantics and action pragmatics, respectively). Recent evidence from language comprehension and action simulation supports the claim that action pragmatics and action semantics draw on common representational resources, thus challenging the traditional divide between declarative and procedural action knowledge. To account for these observations, three kinds of theoretical frameworks are discussed: (i) semantics is grounded in pragmatics, (ii) pragmatics is anchored in semantics, and (iii) pragmatics is part and parcel of semantics.

  11. The Consortium for Evidence Based Research in Rural Educational Settings (CEBRRES): Applying Collaborative Action Research as a Means of Enhancing the Development of Rural Middle School Science Teachers

    Science.gov (United States)

    Wulff, A. H.

    2006-05-01

    Kentucky ranks third in the U.S. in need of rural education attention. Rural schools in Kentucky serve nearly 40% of the total student population, and graduation rates and NAEP scores are low. A two-year pilot study is being completed addressing psychological, social, and content knowledge based constructs, as they apply to science and mathematics achievement in rural environments. The goals are to identify the key aspects of rural teachers knowledge and skills, use a framework to describe how knowledge and skills develop in the rural classroom, apply a useful model of intervention to promote teacher development and increased student learning. If proven successful the knowledge can be incorporated into the practice of current teaching and preservice pedagogical methods. The problem that was identified and addressed by CEBRRES is the high level of student disengagement and the shortage of rigorous stimulating curriculum models. The action taken was the development and implementation of model eliciting activities. Teachers at the target school were expected to utilize action research methodology to execute model-eliciting activities in the classroom, and then communicate results in forms that are useful for other teachers. Benefits to teachers included stipends, increased science content depth and breadth, support to achieve "highly qualified teacher status", extensive professional development, and technology, equipment, and supplies for their school. Survey instruments were devised to address school perceptions (61% worry that they are not doing well enough in school), future plans (80% expect to attend college vs. the current 47.5%), various self concepts, academic self concepts (23% feel that learning is difficult for them), and family self concepts. Science was identified by the students as the subject that interests them the most, followed by math, yet Kentucky ranks near the bottom of the U.S. in math and science training in the workplace. Geology

  12. Infrared neural stimulation (INS) inhibits electrically evoked neural responses in the deaf white cat

    Science.gov (United States)

    Richter, Claus-Peter; Rajguru, Suhrud M.; Robinson, Alan; Young, Hunter K.

    2014-03-01

    Infrared neural stimulation (INS) has been used in the past to evoke neural activity from hearing and partially deaf animals. All the responses were excitatory. In Aplysia californica, Duke and coworkers demonstrated that INS also inhibits neural responses [1], which similar observations were made in the vestibular system [2, 3]. In deaf white cats that have cochleae with largely reduced spiral ganglion neuron counts and a significant degeneration of the organ of Corti, no cochlear compound action potentials could be observed during INS alone. However, the combined electrical and optical stimulation demonstrated inhibitory responses during irradiation with infrared light.

  13. Radioactive fallout and neural tube defects

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