WorldWideScience

Sample records for providing neurophysiological explanations

  1. [Mental Imagery: Neurophysiology and Implications in Psychiatry].

    Science.gov (United States)

    Martínez, Nathalie Tamayo

    2014-03-01

    To provide an explanation about what mental imagery is and some implications in psychiatry. This article is a narrative literature review. There are many terms in which imagery representations are described in different fields of research. They are defined as perceptions in the absence of an external stimulus, and can be created in any sensory modality. Their neurophysiological substrate is almost the same as the one activated during sensory perception. There is no unified theory about its function, but it is possibly the way that our brain uses and manipulates the information to respond to the environment. Mental imagery is an everyday phenomenon, and when it occurs in specific patterns it can be a sign of mental disorders. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  2. The neurophysiology of paediatric movement disorders.

    Science.gov (United States)

    McClelland, Verity M

    2017-12-01

    To demonstrate how neurophysiological tools have advanced our understanding of the pathophysiology of paediatric movement disorders, and of neuroplasticity in the developing brain. Delineation of corticospinal tract connectivity using transcranial magnetic stimulation (TMS) is being investigated as a potential biomarker for response to therapy. TMS measures of cortical excitability and neuroplasticity are also being used to investigate the effects of therapy, demonstrating neuroplastic changes that relate to functional improvements. Analyses of evoked potentials and event-related changes in the electroencephalogaphy spectral activity provide growing evidence for the important role of aberrant sensory processing in the pathophysiology of many different movement disorders. Neurophysiological findings demonstrate that children with clinically similar phenotypes may have differing underlying pathophysiology, which in turn may explain differential response to therapy. Neurophysiological parameters can act as biomarkers, providing a means to stratify individuals, and are well suited to provide biofeedback. They therefore have enormous potential to facilitate improvements to therapy. Although currently a small field, the role of neurophysiology in paediatric movement disorders is poised to expand, both fuelled by and contributing to the rapidly growing fields of neuro-rehabilitation and neuromodulation and the move towards a more individualized therapeutic approach.

  3. Neurophysiological studies may provide a misleading picture of how perceptual-motor interactions are coordinated

    NARCIS (Netherlands)

    Mann, D.L.; Dicks, M.; Canal Bruland, R.; van der Kamp, J.

    2013-01-01

    Neurophysiological measurement techniques like fMRI and TMS are increasingly being used to examine the perceptual-motor processes underpinning the ability to anticipate the actions of others. Crucially, these techniques invariably restrict the experimental task that can be used and consequently

  4. Neurophysiological influence of musical training on speech perception.

    Science.gov (United States)

    Shahin, Antoine J

    2011-01-01

    Does musical training affect our perception of speech? For example, does learning to play a musical instrument modify the neural circuitry for auditory processing in a way that improves one's ability to perceive speech more clearly in noisy environments? If so, can speech perception in individuals with hearing loss (HL), who struggle in noisy situations, benefit from musical training? While music and speech exhibit some specialization in neural processing, there is evidence suggesting that skills acquired through musical training for specific acoustical processes may transfer to, and thereby improve, speech perception. The neurophysiological mechanisms underlying the influence of musical training on speech processing and the extent of this influence remains a rich area to be explored. A prerequisite for such transfer is the facilitation of greater neurophysiological overlap between speech and music processing following musical training. This review first establishes a neurophysiological link between musical training and speech perception, and subsequently provides further hypotheses on the neurophysiological implications of musical training on speech perception in adverse acoustical environments and in individuals with HL.

  5. Human skin wetness perception: psychophysical and neurophysiological bases

    Science.gov (United States)

    Filingeri, Davide; Havenith, George

    2015-01-01

    The ability to perceive thermal changes in the surrounding environment is critical for survival. However, sensing temperature is not the only factor among the cutaneous sensations to contribute to thermoregulatory responses in humans. Sensing skin wetness (i.e. hygrosensation) is also critical both for behavioral and autonomic adaptations. Although much has been done to define the biophysical role of skin wetness in contributing to thermal homeostasis, little is known on the neurophysiological mechanisms underpinning the ability to sense skin wetness. Humans are not provided with skin humidity receptors (i.e., hygroreceptors) and psychophysical studies have identified potential sensory cues (i.e. thermal and mechanosensory) which could contribute to sensing wetness. Recently, a neurophysiological model of human wetness sensitivity has been developed. In helping clarifying the peripheral and central neural mechanisms involved in sensing skin wetness, this model has provided evidence for the existence of a specific human hygrosensation strategy, which is underpinned by perceptual learning via sensory experience. Remarkably, this strategy seems to be shared by other hygroreceptor-lacking animals. However, questions remain on whether these sensory mechanisms are underpinned by specific neuromolecular pathways in humans. Although the first study on human wetness perception dates back to more than 100 years, it is surprising that the neurophysiological bases of such an important sensory feature have only recently started to be unveiled. Hence, to provide an overview of the current knowledge on human hygrosensation, along with potential directions for future research, this review will examine the psychophysical and neurophysiological bases of human skin wetness perception. PMID:27227008

  6. Explanation and inference: Mechanistic and functional explanations guide property generalization

    Directory of Open Access Journals (Sweden)

    Tania eLombrozo

    2014-09-01

    Full Text Available The ability to generalize from the known to the unknown is central to learning and inference. Two experiments explore the relationship between how a property is explained and how that property is generalized to novel species and artifacts. The experiments contrast the consequences of explaining a property mechanistically, by appeal to parts and processes, with the consequences of explaining the property functionally, by appeal to functions and goals. The findings suggest that properties that are explained functionally are more likely to be generalized on the basis of shared functions, with a weaker relationship between mechanistic explanations and generalization on the basis of shared parts and processes. The influence of explanation type on generalization holds even though all participants are provided with the same mechanistic and functional information, and whether an explanation type is freely generated (Experiment 1, experimentally provided (Experiment 2, or experimentally induced (Experiment 2. The experiments also demonstrate that explanations and generalizations of a particular type (mechanistic or functional can be experimentally induced by providing sample explanations of that type, with a comparable effect when the sample explanations come from the same domain or from a different domains. These results suggest that explanations serve as a guide to generalization, and contribute to a growing body of work supporting the value of distinguishing mechanistic and functional explanations.

  7. Explanation and inference: mechanistic and functional explanations guide property generalization.

    Science.gov (United States)

    Lombrozo, Tania; Gwynne, Nicholas Z

    2014-01-01

    The ability to generalize from the known to the unknown is central to learning and inference. Two experiments explore the relationship between how a property is explained and how that property is generalized to novel species and artifacts. The experiments contrast the consequences of explaining a property mechanistically, by appeal to parts and processes, with the consequences of explaining the property functionally, by appeal to functions and goals. The findings suggest that properties that are explained functionally are more likely to be generalized on the basis of shared functions, with a weaker relationship between mechanistic explanations and generalization on the basis of shared parts and processes. The influence of explanation type on generalization holds even though all participants are provided with the same mechanistic and functional information, and whether an explanation type is freely generated (Experiment 1), experimentally provided (Experiment 2), or experimentally induced (Experiment 2). The experiments also demonstrate that explanations and generalizations of a particular type (mechanistic or functional) can be experimentally induced by providing sample explanations of that type, with a comparable effect when the sample explanations come from the same domain or from a different domains. These results suggest that explanations serve as a guide to generalization, and contribute to a growing body of work supporting the value of distinguishing mechanistic and functional explanations.

  8. Exploring the potential of neurophysiological measures for user-adaptive visualization

    OpenAIRE

    Tak, S.; Brouwer, A.M.; Toet, A.; Erp, J.B.F. van

    2013-01-01

    User-adaptive visualization aims to adapt visualized information to the needs and characteristics of the individual user. Current approaches deploy user personality factors, user behavior and preferences, and visual scanning behavior to achieve this goal. We argue that neurophysiological data provide valuable additional input for user-adaptive visualization systems since they contain a wealth of objective information about user characteristics. The combination of neurophysiological data with ...

  9. Neurophysiological Studies May Provide a Misleading Picture of How Perceptual-Motor Interactions are Coordinated

    Directory of Open Access Journals (Sweden)

    David Mann

    2013-02-01

    Full Text Available Neurophysiological measurement techniques like fMRI and TMS are increasingly being used to examine the perceptual-motor processes underpinning the ability to anticipate the actions of others. Crucially, these techniques invariably restrict the experimental task that can be used and consequently limit the degree to which the findings can be generalised. These limitations are discussed based on a recent paper by Tomeo et al. (2012 who sought to examine responses to fooling actions by using TMS on participants who passively observed spliced video clips where bodily information was, and was not, linked to the action outcome. We outline two particular concerns with this approach. First, spliced video clips that show physically impossible actions are unlikely to simulate a “fooling” action. Second, it is difficult to make meaningful inferences about perceptual-motor expertise from experiments where participants cannot move. Taken together, we argue that wider generalisations based on these findings may provide a misunderstanding of the phenomenon such a study is designed to explore.

  10. Neurophysiological studies may provide a misleading picture of how perceptual-motor interactions are coordinated.

    Science.gov (United States)

    Mann, David; Dicks, Matt; Cañal-Bruland, Rouwen; van der Kamp, John

    2013-01-01

    Neurophysiological measurement techniques like fMRI and TMS are increasingly being used to examine the perceptual-motor processes underpinning the ability to anticipate the actions of others. Crucially, these techniques invariably restrict the experimental task that can be used and consequently limit the degree to which the findings can be generalised. These limitations are discussed based on a recent paper by Tomeo et al. (2012) who sought to examine responses to fooling actions by using TMS on participants who passively observed spliced video clips where bodily information was, and was not, linked to the action outcome. We outline two particular concerns with this approach. First, spliced video clips that show physically impossible actions are unlikely to simulate a "fooling" action. Second, it is difficult to make meaningful inferences about perceptual-motor expertise from experiments where participants cannot move. Taken together, we argue that wider generalisations based on these findings may provide a misunderstanding of the phenomenon such a study is designed to explore.

  11. Customer needs, expectations, and satisfaction with clinical neurophysiology services in Ireland: a case for tele-neurophysiology development.

    Science.gov (United States)

    Fitzsimons, M; Ronan, L; Murphy, K; Browne, G; Connolly, S; McMenamin, J; Delanty, N

    2004-01-01

    Although equitable access to services should be based on need, geographical location of patients and their clinicians can give rise to inequalities in healthcare delivery. Development of tele-medicine services can improve equity of access. The specialty of Clinical Neurophysiology (CN), currently under-developed in Ireland provides an example of such potential. This study aimed to determine the needs, expectations, and satisfaction of CN customers, namely patients and referring clinicians. The goal was to examine geographical impediments to access that might be addressed by the introduction of tele-neurophysiology. Two customer surveys were conducted: CN referring clinicians and CN patients. Thirty-one North Western Health Board (NWHB) consultant clinicians responded to a postal survey. Distance and delays caused by long waiting lists were felt to deter or make CN referral irrelevant. Ninety-seven percent believed the lack of a local service negatively impacts on patient management and 93% would welcome the introduction of a tele-neurophysiology service. The geographical location of patient's residence and/or the location of the referring clinician's practice influenced waiting lists for CN. Fifty-eight (105/182) percent of patients living in a region with a CN service compared to 39% (50/128) of those living in a region with no service received an appointment within one month. In addition to the current insufficient CN service capacity in Ireland, these surveys highlighted geographical inequities. Tele-neurophysiology has the potential to speed-up diagnosis, result in more patients being appropriately investigated and be fairer to patients.

  12. Incorporating neurophysiological concepts in mathematical thermoregulation models

    Science.gov (United States)

    Kingma, Boris R. M.; Vosselman, M. J.; Frijns, A. J. H.; van Steenhoven, A. A.; van Marken Lichtenbelt, W. D.

    2014-01-01

    Skin blood flow (SBF) is a key player in human thermoregulation during mild thermal challenges. Various numerical models of SBF regulation exist. However, none explicitly incorporates the neurophysiology of thermal reception. This study tested a new SBF model that is in line with experimental data on thermal reception and the neurophysiological pathways involved in thermoregulatory SBF control. Additionally, a numerical thermoregulation model was used as a platform to test the function of the neurophysiological SBF model for skin temperature simulation. The prediction-error of the SBF-model was quantified by root-mean-squared-residual (RMSR) between simulations and experimental measurement data. Measurement data consisted of SBF (abdomen, forearm, hand), core and skin temperature recordings of young males during three transient thermal challenges (1 development and 2 validation). Additionally, ThermoSEM, a thermoregulation model, was used to simulate body temperatures using the new neurophysiological SBF-model. The RMSR between simulated and measured mean skin temperature was used to validate the model. The neurophysiological model predicted SBF with an accuracy of RMSR human thermoregulation models can be equipped with SBF control functions that are based on neurophysiology without loss of performance. The neurophysiological approach in modelling thermoregulation is favourable over engineering approaches because it is more in line with the underlying physiology.

  13. [Mixed depressions: clinical and neurophysiological biomarkers].

    Science.gov (United States)

    Micoulaud Franchi, J-A; Geoffroy, P-A; Vion-Dury, J; Balzani, C; Belzeaux, R; Maurel, M; Cermolacce, M; Fakra, E; Azorin, J-M

    2013-12-01

    Epidemiological studies of major depressive episodes (MDE) highlighted the frequent association of symptoms or signs of mania or hypomania with depressive syndrome. Beyond the strict definition of DSM-IV, epidemiological recognition of a subset of MDE characterized by the presence of symptoms or signs of the opposite polarity is clinically important because it is associated with pejorative prognosis and therapeutic response compared to the subgroup of "typical MDE". The development of DSM-5 took into account the epidemiological data. DSM-5 opted for a more dimensional perspective in implementing the concept of "mixed features" from an "episode" to a "specification" of mood disorder. As outlined in the DSM-5: "Mixed features associated with a major depressive episode have been found to be a significant risk factor for the development of bipolar I and II disorder. As a result, it is clinically useful to note the presence of this specifier for treatment planning and monitoring of response to therapeutic". However, the mixed features are sometimes difficult to identify, and neurophysiological biomarkers would be useful to make a more specific diagnosis. Two neurophysiological models make it possible to better understand MDE with mixed features : i) the emotional regulation model that highlights a tendency to hyper-reactive and unstable emotion response, and ii) the vigilance regulation model that highlights, through EEG recording, a tendency to unstable vigilance. Further research is required to better understand relationships between these two models. These models provide the opportunity of a neurophysiological framework to better understand the mixed features associated with MDE and to identify potential neurophysiological biomarkers to guide therapeutic strategies. Copyright © 2013 L’Encéphale. Published by Elsevier Masson SAS.. All rights reserved.

  14. Clinical neurophysiology referral patterns to a tertiary hospital--a prospective audit.

    LENUS (Irish Health Repository)

    Renganathan, R

    2012-02-03

    BACKGROUND: Cork University Hospital (CUH) provides a tertiary service for all neurophysiology referrals in the Southern Health Board region. AIM: To ascertain the number, source, symptoms and diagnosis of neurophysiology referrals at CUH. METHODS: We did a prospective audit of the referral patterns to the neurophysiology department over a 12 -week period. RESULTS: Of 635 referrals, 254 had electromyograms (EMG), 359 had electro-encephalograms (EEG), 18 had visual evoked potentials (VEP), three had somato-sensory evoked potentials (SSEP) and one had multiple sleep latency tests (MSLT). We analysed the demographic pattern, reason for referrals, the average waiting time for neurophysiology tests and the patterns of diagnosis in this audit. CONCLUSIONS: Patients from County Cork are making more use of the neurophysiology services than patients from other counties within the Southern Health Board. The average waiting time for an EEG was 32 days and for an EMG was 74 days. However, more than 35% of those patients waiting for an EEG or an EMG had their tests done within four weeks of referral. The appointments of EEG and EMG were assigned on the basis of clinical need.

  15. Neurophysiological evidence of methylmercury neurotoxicity

    DEFF Research Database (Denmark)

    Murata, Katsuyuki; Grandjean, Philippe; Dakeishi, Miwako

    2007-01-01

    neurotoxicity and to examine the usefulness of those measures. METHODS: The reports addressing both neurophysiological measures and methylmercury exposure in humans were identified and evaluated. RESULTS: The neurological signs and symptoms of MD included paresthesias, constriction of visual fields, impairment...... disease (MD; methylmercury poisoning). In recent years, some of these methods have been used for the risk assessment of low-level methylmercury exposure in asymptomatic children. The objectives of this article were to present an overview of neurophysiological findings involved in methylmercury...... of hearing and speech, mental disturbances, excessive sweating, and hypersalivation. Neuropathological lesions involved visual, auditory, and post- and pre-central cortex areas. Neurophysiological changes involved in methylmercury, as assessed by EPs and HRV, were found to be in accordance with both clinical...

  16. [Neurophysiology of pruritus].

    Science.gov (United States)

    Raap, U; Ikoma, A; Kapp, A

    2006-05-01

    Neurophysiologic studies indicate that pruritus is a distinct sensation with its own neuronal pathways in the peripheral and central nervous system which are different from that of pain. Pruritus is a very disturbing sensation and most common skin-related symptom. Histamine was long considered to be the only mediator of pruritus. However, it has become evident that - besides histamine - a variety of neuromediators such as neurotrophins and neuropeptides as well as their receptors play an important role in pruritus. Neuromediators are produced by mast cells, keratinocytes and eosinophil granulocytes which are in close contact to sensory nerves. The discovery of these neurophysiological interactions opens new and promising therapeutic options for the treatment of pruritus.

  17. Students Performance And Perception Of Neurophysiology ...

    African Journals Online (AJOL)

    We also surveyed learning experience of a batch of graduating doctors in neurosciences (n=50) and surveyed the staff and students' perception of the teaching of neurophysiology. The students performances in neurophysiology was comparatively poorer than in cardiovascular and endocrinology aspects of the subject over ...

  18. Neurophysiology of Drosophila Models of Parkinson's Disease

    OpenAIRE

    West, Ryan J. H.; Furmston, Rebecca; Williams, Charles A. C.; Elliott, Christopher J. H.

    2015-01-01

    We provide an insight into the role Drosophila has played in elucidating neurophysiological perturbations associated with Parkinson's disease- (PD-) related genes. Synaptic signalling deficits are observed in motor, central, and sensory systems. Given the neurological impact of disease causing mutations within these same genes in humans the phenotypes observed in fly are of significant interest. As such we observe four unique opportunities provided by fly nervous system models of Parkinson's ...

  19. Neurophysiological responses during cooking food associated with different emotions

    NARCIS (Netherlands)

    Brouwer, A.M.; Hogervorst, M.A.; Grootjen, M.; Erp, J.B.F. van; Zandstra, E.H.

    2017-01-01

    Neurophysiological correlates of affective experience could potentially provide continuous information about a person’s experience when cooking and tasting food, without explicitly verbalizing this. Such measures would be helpful to understand people’s implicit food preferences and choices. This

  20. Evaluation of TV commercials using neurophysiological responses.

    Science.gov (United States)

    Yang, Taeyang; Lee, Do-Young; Kwak, Youngshin; Choi, Jinsook; Kim, Chajoong; Kim, Sung-Phil

    2015-04-24

    In recent years, neuroscientific knowledge has been applied to marketing as a novel and efficient means to comprehend the cognitive and behavioral aspects of consumers. A number of studies have attempted to evaluate media contents, especially TV commercials using various neuroimaging techniques such as electroencephalography (EEG). Yet neurophysiological examination of detailed cognitive and affective responses in viewers is still required to provide practical information to marketers. Here, this study develops a method to analyze temporal patterns of EEG data and extract affective and cognitive indices such as happiness, surprise, and attention for TV commercial evaluation. Twenty participants participated in the study. We developed the neurophysiological indices for TV commercial evaluation using classification model. Specifically, these model-based indices were customized using individual EEG features. We used a video game for developing the index of attention and four video clips for developing indices of happiness and surprise. Statistical processes including one-way analyses of variance (ANOVA) and the cross validation scheme were used to select EEG features for each index. The EEG features were composed of the combinations of spectral power at selected channels from the cross validation for each individual. The Fisher's linear discriminant classifier (FLDA) was used to estimate each neurophysiological index during viewing four different TV commercials. Post hoc behavioral responses of preference, short-term memory, and recall were measured. Behavioral results showed significant differences for all preference, short-term memory rates, and recall rates between commercials, leading to a 'high-ranked' commercial group and a 'low-ranked' group (P < 0.05). Neural estimation of happiness results revealed a significant difference between the high-ranked and the low-ranked commercials in happiness index (P < 0.01). The order of rankings based on happiness and

  1. Preliminary evidence of a neurophysiological basis for individual discrimination in filial imprinting.

    Science.gov (United States)

    Town, Stephen Michael

    2011-12-01

    Filial imprinting involves a predisposition for biologically important stimuli and a learning process directing preferences towards a particular stimulus. Learning underlies discrimination between imprinted and unfamiliar individuals and depends upon the IMM (intermediate and medial mesopallium). Here, IMM neurons responded differentially to familiar and unfamiliar conspecifics following socialization and the neurophysiological effects of social experience differed between hemispheres. Such findings may provide a neurophysiological basis for individual discrimination in imprinting. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Neurophysiological effects of lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, I.; Wildt, K.; Gullberg, B.; Berlin, M.

    1983-10-01

    A series of neurophysiological variables was measured for men occupationally exposed to lead. The results were related to the degree of lead exposure and to the concentrations of lead and zinc protoporphyrin in blood. A small but significant correlation was observed between lead exposure and motor and sensory conduction velocities in the lower limbs, the conduction velocities of slow motor fibers in the upper limbs, and also sensory nerve action potentials. It is suggested that a neurophysiological examination should be considered in the surveillance of the health of lead workers.

  3. Supporting students' scientific explanations: A case study investigating the synergy focusing on a teacher's practices when providing instruction and using mobile devices

    Science.gov (United States)

    Delen, Ibrahim

    Engage students in constructing scientific practices is a critical component of science instruction. Therefore a number of researchers have developed software programs to help students and teachers in this hard task. The Zydeco group, designed a mobile application called Zydeco, which enables students to collect data inside and outside the classroom, and then use the data to create scientific explanations by using claim-evidence-reasoning framework. Previous technologies designed to support scientific explanations focused on how these programs improve students' scientific explanations, but these programs ignored how scientific explanation technologies can support teacher practices. Thus, to increase our knowledge how different scaffolds can work together, this study aimed to portray the synergy between a teacher's instructional practices (part 1) and using supports within a mobile devices (part 2) to support students in constructing explanations. Synergy can be thought of as generic and content-specific scaffolds working together to enable students to accomplish challenging tasks, such as creating explanations that they would not normally be able to do without the scaffolds working together. Providing instruction (part 1) focused on understanding how the teacher scaffolds students' initial understanding of the claim-evidence-reasoning (CER) framework. The second component of examining synergy (part 2: using mobile devices) investigated how this teacher used mobile devices to provide feedback when students created explanations. The synergy between providing instruction and using mobile devices was investigated by analyzing a middle school teacher's practices in two different units (plants and water quality). Next, this study focused on describing how the level of synergy influenced the quality of students' scientific explanations. Finally, I investigated the role of focused teaching intervention sessions to inform teacher in relation to students' performance. In

  4. Creating visual explanations improves learning.

    Science.gov (United States)

    Bobek, Eliza; Tversky, Barbara

    2016-01-01

    Many topics in science are notoriously difficult for students to learn. Mechanisms and processes outside student experience present particular challenges. While instruction typically involves visualizations, students usually explain in words. Because visual explanations can show parts and processes of complex systems directly, creating them should have benefits beyond creating verbal explanations. We compared learning from creating visual or verbal explanations for two STEM domains, a mechanical system (bicycle pump) and a chemical system (bonding). Both kinds of explanations were analyzed for content and learning assess by a post-test. For the mechanical system, creating a visual explanation increased understanding particularly for participants of low spatial ability. For the chemical system, creating both visual and verbal explanations improved learning without new teaching. Creating a visual explanation was superior and benefitted participants of both high and low spatial ability. Visual explanations often included crucial yet invisible features. The greater effectiveness of visual explanations appears attributable to the checks they provide for completeness and coherence as well as to their roles as platforms for inference. The benefits should generalize to other domains like the social sciences, history, and archeology where important information can be visualized. Together, the findings provide support for the use of learner-generated visual explanations as a powerful learning tool.

  5. Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review.

    Science.gov (United States)

    Kesić, Srdjan; Spasić, Sladjana Z

    2016-09-01

    For more than 20 years, Higuchi's fractal dimension (HFD), as a nonlinear method, has occupied an important place in the analysis of biological signals. The use of HFD has evolved from EEG and single neuron activity analysis to the most recent application in automated assessments of different clinical conditions. Our objective is to provide an updated review of the HFD method applied in basic and clinical neurophysiological research. This article summarizes and critically reviews a broad literature and major findings concerning the applications of HFD for measuring the complexity of neuronal activity during different neurophysiological conditions. The source of information used in this review comes from the PubMed, Scopus, Google Scholar and IEEE Xplore Digital Library databases. The review process substantiated the significance, advantages and shortcomings of HFD application within all key areas of basic and clinical neurophysiology. Therefore, the paper discusses HFD application alone, combined with other linear or nonlinear measures, or as a part of automated methods for analyzing neurophysiological signals. The speed, accuracy and cost of applying the HFD method for research and medical diagnosis make it stand out from the widely used linear methods. However, only a combination of HFD with other nonlinear methods ensures reliable and accurate analysis of a wide range of neurophysiological signals. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Evaluation of TV commercials using neurophysiological responses

    OpenAIRE

    Yang, Taeyang; Lee, Do-Young; Kwak, Youngshin; Choi, Jinsook; Kim, Chajoong; Kim, Sung-Phil

    2015-01-01

    Background In recent years, neuroscientific knowledge has been applied to marketing as a novel and efficient means to comprehend the cognitive and behavioral aspects of consumers. A number of studies have attempted to evaluate media contents, especially TV commercials using various neuroimaging techniques such as electroencephalography (EEG). Yet neurophysiological examination of detailed cognitive and affective responses in viewers is still required to provide practical information to market...

  7. Neuromuscular deficits after peripheral joint injury: a neurophysiological hypothesis.

    Science.gov (United States)

    Ward, Sarah; Pearce, Alan J; Pietrosimone, Brian; Bennell, Kim; Clark, Ross; Bryant, Adam L

    2015-03-01

    In addition to biomechanical disturbances, peripheral joint injuries (PJIs) can also result in chronic neuromuscular alterations due in part to loss of mechanoreceptor-mediated afferent feedback. An emerging perspective is that PJI should be viewed as a neurophysiological dysfunction, not simply a local injury. Neurophysiological and neuroimaging studies have provided some evidence for central nervous system (CNS) reorganization at both the cortical and spinal levels after PJI. The novel hypothesis proposed is that CNS reorganization is the underlying mechanism for persisting neuromuscular deficits after injury, particularly muscle weakness. There is a lack of direct evidence to support this hypothesis, but future studies utilizing force-matching tasks with superimposed transcranial magnetic stimulation may be help clarify this notion. © 2014 Wiley Periodicals, Inc.

  8. Neurophysiological basis of rehabilitation of adolescent idiopathic scoliosis.

    Science.gov (United States)

    Smania, Nicola; Picelli, Alessandro; Romano, Michele; Negrini, Stefano

    2008-01-01

    Knowledge on mechanisms of neurophysiological control of trunk movement and posture could help in the development of rehabilitation programs and brace treatment in adolescent idiopathic scoliosis (AIS). Reviewing up-to-date research on neurophysiology of movement and posture control with the aim of providing basis for new researches in the field of AIS rehabilitation and background understanding for clinicians engaged in management of AIS. Review of literature. We considered several neurophysiological issues relevant for AIS rehabilitation, namely, the peculiar organization of patterns of trunk muscle recruitment, the structure of the neural hardware subserving axial and arm muscle control, and the relevance of cognitive systems allowing mapping of spatial coordinates and building of body schema. We made clear the reason why trunk control is generally carried out by means of very fast, feedforward or feedback driven patterns of muscle activation which are deeply rooted in our neural control system and very difficult to modify by training. We hypothesized that augmented sensory feedback and strength exercises could be an important stage in a rehabilitation program aimed at hindering, or possibly reversing, scoliosis progression. In this context we considered bracing not only as a corrective biomechanical device but also as a tool for continuous sensory stimulation that could help awareness of body misalignment. Future research aimed at developing strategies of trunk postural control learning is essential in the rehabilitation of adolescent idiopathic scoliosis.

  9. Neurophysiology of conversion disorders: a historical perspective.

    Science.gov (United States)

    Crommelinck, M

    2014-10-01

    The aim of this paper is to present a short historical perspective on the neurophysiological approach to hysteria and conversion disorders. The body of this paper will be constituted of three main parts. In the first part, we will present the significant progress due to some pioneers of neurology/psychiatry during the XIXth century. As we shall see, this period was particularly rich in personalities whose work gradually laid the foundations to a true medical approach to hysteria. In the first half of the XXth century, different factors have led to a long eclipse of the neurological approach to hysteria. In the second part, we will show how, by the 1960's-1970's, the conceptual and methodological advances in neurophysiology, as well as the turning point of cognitive sciences (and cognitive psychology in particular) allowed a gradual reinstatement of hysteria within the fields of neurology and clinical neurophysiology. Finally, and this is the third part of this paper, we will show how over the past three decades, an entirely new neurophysiological approach to hysteria and conversion disorders has emerged. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  10. Neurophysiology and neural engineering: a review.

    Science.gov (United States)

    Prochazka, Arthur

    2017-08-01

    Neurophysiology is the branch of physiology concerned with understanding the function of neural systems. Neural engineering (also known as neuroengineering) is a discipline within biomedical engineering that uses engineering techniques to understand, repair, replace, enhance, or otherwise exploit the properties and functions of neural systems. In most cases neural engineering involves the development of an interface between electronic devices and living neural tissue. This review describes the origins of neural engineering, the explosive development of methods and devices commencing in the late 1950s, and the present-day devices that have resulted. The barriers to interfacing electronic devices with living neural tissues are many and varied, and consequently there have been numerous stops and starts along the way. Representative examples are discussed. None of this could have happened without a basic understanding of the relevant neurophysiology. I also consider examples of how neural engineering is repaying the debt to basic neurophysiology with new knowledge and insight. Copyright © 2017 the American Physiological Society.

  11. Theory-based explanation as intervention.

    Science.gov (United States)

    Weisman, Kara; Markman, Ellen M

    2017-10-01

    Cogent explanations are an indispensable means of providing new information and an essential component of effective education. Beyond this, we argue that there is tremendous untapped potential in using explanations to motivate behavior change. In this article we focus on health interventions. We review four case studies that used carefully tailored explanations to address gaps and misconceptions in people's intuitive theories, providing participants with a conceptual framework for understanding how and why some recommended behavior is an effective way of achieving a health goal. These case studies targeted a variety of health-promoting behaviors: (1) children washing their hands to prevent viral epidemics; (2) parents vaccinating their children to stem the resurgence of infectious diseases; (3) adults completing the full course of an antibiotic prescription to reduce antibiotic resistance; and (4) children eating a variety of healthy foods to improve unhealthy diets. Simply telling people to engage in these behaviors has been largely ineffective-if anything, concern about these issues is mounting. But in each case, teaching participants coherent explanatory frameworks for understanding health recommendations has shown great promise, with such theory-based explanations outperforming state-of-the-art interventions from national health authorities. We contrast theory-based explanations both with simply listing facts, information, and advice and with providing a full-blown educational curriculum, and argue for providing the minimum amount of information required to understand the causal link between a target behavior and a health outcome. We argue that such theory-based explanations lend people the motivation and confidence to act on their new understanding.

  12. Explanations - Styles of explanation in science

    Science.gov (United States)

    Cornwell, John

    2004-06-01

    Our lives, states of health, relationships, behavior, experiences of the natural world, and the technologies that shape our contemporary existence are subject to a superfluity of competing, multi-faceted and sometimes incompatible explanations. Widespread confusion about the nature of "explanation" and its scope and limits pervades popular exposition of the natural sciences, popular history and philosophy of science. This fascinating book explores the way explanations work, why they vary between disciplines, periods, and cultures, and whether they have any necessary boundaries. In other words, Explanations aims to achieve a better understanding of explanation, both within the sciences and the humanities. It features contributions from expert writers from a wide range of disciplines, including science, philosophy, mathematics, and social anthropology.

  13. [The links between neuropsychology and neurophysiology].

    Science.gov (United States)

    Stolarska-Weryńska, Urszula; Biedroń, Agnieszka; Kaciński, Marek

    2016-01-01

    The aim of the study was to establish current scope of knowledge regarding associations between neurophysiological functioning, neuropsychology and psychoterapy. A systematic review was performed including 93 publications from Science Server, which contains the collections of Elsevier, Springer Journals, SCI-Ex/ICM, MEDLINE/PubMed, and SCOPUS. The works have been selected basing on following key words: 'neuropsychology, neurocognitive correlates, electrodermal response, event related potential, EEG, pupillography, electromiography' out of papers published between 2004-2015. Present reports on the use of neurophysiological methods in psychology can be divided into two areas: experimental research and research of the practical use of conditioning techniques and biofeedback in the treatment of somatic disease. Among the experimental research the following have been distinguished: research based on the startle reflex, physiological reaction to novelty, stress, type/amount of cognitive load and physiological correlates of emotion; research on the neurophysiological correlates of mental disorders, mostly mood and anxiety disorders, and neurocognitive correlates: of memory, attention, learning and intelligence. Among papers regarding the use of neurophysiological methods in psychology two types are the most frequent: on the mechanisms of biofeedback, related mainly to neuro- feedback, which is a quickly expanding method of various attention and mental disorders'treatment, and also research of the use of conditioning techniques in the treatment of mental disorders, especially depression and anxiety. A special place among all the above is taken by the research on electrophysiological correlates of psychotherapy, aiming to differentiate between the efficacy of various psychotherapeutic schools (the largest amount of publications regard the efficacy of cognitive-behavioral psychotherapy) in patients of different age groups and different diagnosis.

  14. Functional Neuroanatomy and Neurophysiology of Functional Neurological Disorders (Conversion Disorder).

    Science.gov (United States)

    Voon, Valerie; Cavanna, Andrea E; Coburn, Kerry; Sampson, Shirlene; Reeve, Alya; LaFrance, W Curt

    2016-01-01

    Much is known regarding the physical characteristics, comorbid symptoms, psychological makeup, and neuropsychological performance of patients with functional neurological disorders (FNDs)/conversion disorders. Gross neurostructural deficits do not account for the patients' deficits or symptoms. This review describes the literature focusing on potential neurobiological (i.e. functional neuroanatomic/neurophysiological) findings among individuals with FND, examining neuroimaging and neurophysiological studies of patients with the various forms of motor and sensory FND. In summary, neural networks and neurophysiologic mechanisms may mediate "functional" symptoms, reflecting neurobiological and intrapsychic processes.

  15. Neurophysiology of action anticipation in athletes: A systematic review.

    Science.gov (United States)

    Smith, Daniel M

    2016-01-01

    The purpose of this study was to provide a systematic review of action anticipation studies using functional neuroimaging or brain stimulation during a sport-specific anticipation task. A total of 15 studies from 2008 to 2014 were evaluated and are reported in four sections: expert-novice samples, action anticipation tasks, neuroimaging and stimulation techniques, and key findings. Investigators examined a wide range of action anticipation scenarios specific to eight different sports and utilized functional magnetic resonance imaging (fMRI), electroencephalogram (EEG), and transcranial magnetic stimulation (TMS). Expert-novice comparisons were commonly used to investigate differences in action anticipation performance and neurophysiology. Experts tended to outperform novices, and an extensive array of brain structures were reported to be involved differently for experts and novices during action anticipation. However, these neurophysiological findings were generally inconsistent across the studies reviewed. The discussion focuses on strengths and four key limitations. The conclusion posits remaining questions and recommendations for future research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Automated Explanation for Educational Applications.

    Science.gov (United States)

    Suthers, Daniel D.

    1991-01-01

    Artificial intelligence techniques available for generating explanations for teaching purposes are surveyed, and the way in which they are combined in a computer program that provides explanations is described. The program responds to questions in the physical sciences. Potential contributions of this technology to computer-based education are…

  17. Neurophysiological appropriateness of ionizing radiation effects

    International Nuclear Information System (INIS)

    Nyagu, A.I.; Loganovsky, K.N.

    1997-01-01

    The goal of this study was to compare bioelectrical activity of the brain in remote period of acute radiation sickness (ARS), chronic and prenatal irradiation as a result of the Chernobyl disaster. Registration of computerized 19-channel EEG, visual and somato-sensory evoked potentials have been carried out for 70 patients who had a verified ARS, 100 Chernobyl disaster survivors, who have been working in the Chernobyl exclusion zone since 1986-87 during 5 and more years, 50 prenatally irradiated children, and relevant controls. The relative risks of neurophysiological abnormalities are 4.5 for the ARS-patients, 3.6 for the chronically irradiated persons and 3.7 for the prenatally irradiated children. The data obtained testify to possibility of radiation-induced neurophysiological abnormalities in examined Chernobyl accident survivors which seems to be non-stochastic effects of ionizing radiation. For all examined irradiated patients it was typically an increasing of δ- and β- powers of EEG, particularly, in the frontal lobe shifted to the left fronto-temporal region, but spectral power of both θ- and α-range was significantly depressed. Aforesaid signs together with data of evoked potentials reflect the structural and functional abnormalities of limbic system and the left hemisphere as the first revealed neurophysiological appropriateness of ionizing radiation effects. (author)

  18. Neurophysiological appropriateness of ionizing radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    Nyagu, A I; Loganovsky, K N [Department of Neurology, Inst. of Clinical Radiology, Scientific Centre for Radiation Medicine of Academy of Medical Sciences of Ukraine, Kiev (Ukraine)

    1997-11-01

    The goal of this study was to compare bioelectrical activity of the brain in remote period of acute radiation sickness (ARS), chronic and prenatal irradiation as a result of the Chernobyl disaster. Registration of computerized 19-channel EEG, visual and somato-sensory evoked potentials have been carried out for 70 patients who had a verified ARS, 100 Chernobyl disaster survivors, who have been working in the Chernobyl exclusion zone since 1986-87 during 5 and more years, 50 prenatally irradiated children, and relevant controls. The relative risks of neurophysiological abnormalities are 4.5 for the ARS-patients, 3.6 for the chronically irradiated persons and 3.7 for the prenatally irradiated children. The data obtained testify to possibility of radiation-induced neurophysiological abnormalities in examined Chernobyl accident survivors which seems to be non-stochastic effects of ionizing radiation. For all examined irradiated patients it was typically an increasing of {delta}- and {beta}- powers of EEG, particularly, in the frontal lobe shifted to the left fronto-temporal region, but spectral power of both {theta}- and {alpha}-range was significantly depressed. Aforesaid signs together with data of evoked potentials reflect the structural and functional abnormalities of limbic system and the left hemisphere as the first revealed neurophysiological appropriateness of ionizing radiation effects. (author). 25 refs.

  19. Intraoperative neurophysiology of the conus medullaris and cauda equina.

    Science.gov (United States)

    Kothbauer, Karl F; Deletis, Vedran

    2010-02-01

    Intraoperative neurophysiological techniques are becoming routine tools for neurosurgical practice. Procedures affecting the lumbosacral nervous system are frequent in adult and pediatric neurosurgery. This review provides an overview of the techniques utilized in cauda and conus operations. Two basic methodologies of intraoperative neurophysiological testing are utilized during surgery in the lumbosacral spinal canal. Mapping techniques help identify functional neural structures, namely, nerve roots and their respective spinal levels. Monitoring is referred to as the technology to continuously assess the functional integrity of pathways and reflex circuits. For mapping direct electrical stimulation of a structure within the surgical field and recording at a distant site, usually a muscle is the most commonly used setup. Sensory nerve roots or spinal cord areas can be mapped by stimulation of a distant sensory nerve or skin area and recording from a structure within the surgical field. Continuous monitoring of the motor system is done with motor evoked potentials. These are evoked by transcranial electrical stimulation and recorded from lower extremity and sphincter muscles. Presence or absence of muscle responses are the monitored parameters. To monitor the sensory pathways, sensory potentials evoked by tibial, peroneal, or pudendal nerve stimulation and recorded from the dorsal columns with a spinal electrode or as cortical responses from scalp electrodes are used. Amplitudes and latencies of these responses are measured for interpretation. The bulbocavernosus reflex, with stimulation of the pudendal nerve and recording from the external anal sphincter, is used for continuous monitoring of the reflex circuitry. The presence of absence of this response is the pertinent parameter monitored. Stimulation of individual dorsal nerve roots is used to identify those segments that generate spastic activity and which may be cut during selective dorsal rhizotomy

  20. [Neurophysiology of systemic diseases].

    Science.gov (United States)

    Attarian, S

    2004-01-01

    Connective tissue diseases represent a varied and challenging group of disorders. Neuromuscular structures are highly susceptible targets for damage. In this review, the neurophysiological explorations of the neuromuscular complications are examined with particular attention to the peripheral nerve system. The most common presentations are sensorimotor polyneuropathy, mononeuritis multiplex, distal symmetric neuropathy, compression neuropathy and trigeminal sensory neuropathy.

  1. Neurophysiological evaluation of patients with degenerative diseases of the cervical spine

    Directory of Open Access Journals (Sweden)

    Ilić Tihomir V.

    2011-01-01

    Full Text Available Bacground/Aim. Diagnostic protocol for patients with degenerative diseases of the cervical spine demands, in parallel with neuroimaging methods, functional evaluation through neurophysiological methods (somatosensitive and motor evoked potentials and electromyoneurography aiming to evaluate possible subclinical affection of spinal medula resulting in neurological signs of long tract abnormalities. Considering diversities of clinical outcomes for these patients, complex diagnostic evaluation provides a prognosis of the disease progression. Methods. The study included 21 patients (48.24 ± 11.01 years of age with clinical presentation of cervical spondylarthropathy, without neuroradiological signs of myelopathy. For each patient, in addition to conventional neurophysiological tests (somatisensory evoked potentials - SSEP, motor evoked potentials - MEP, electromyoneurography - EMG, nerve conduction studies, we calculated central motor conduction time (CMCTF, as well the same parameter in relation to a different position of the head (maximal anteflexion and retroflexion, so-called dynamic tests. Results. Abnormalities of the peripheral motor neurone by conventional EMNeG was established in 2/3 of the patients, correponding to the findings of root condution time. Prolonged conventional CVMPF were found in 29% of the patients, comparing to 43% CVMPF abnormalities found with the dynamic tests. In addition, the SSEP findings were abnormal in 38% of the patients with degenerative diseases of the cervical spine. Conclusion. An extended neurophysiological protocol of testing corticospinal functions, including dynamic tests of central and periheral motor neurons are relevant for detection of subclinical forms of cervical spondylothic myelopathy, even at early stages. In addition to the conventional neurophysiological tests, we found usefull to include the dynamic motor tests and root conduction time measurement in diagnostic evaluation.

  2. Eliciting explanations: Constraints on when self-explanation aids learning.

    Science.gov (United States)

    Rittle-Johnson, Bethany; Loehr, Abbey M

    2017-10-01

    Generating explanations for oneself in an attempt to make sense of new information (i.e., self-explanation) is often a powerful learning technique. Despite its general effectiveness, in a growing number of studies, prompting for self-explanation improved some aspects of learning, but reduced learning of other aspects. Drawing on this recent research, as well as on research comparing self-explanation under different conditions, we propose four constraints on the effectiveness of self-explanation. First, self-explanation promotes attention to particular types of information, so it is better suited to promote particular learning outcomes in particular types of domains, such as transfer in domains guided by general principles or heuristics. Second, self-explaining a variety of types of information can improve learning, but explaining one's own solution methods or choices may reduce learning under certain conditions. Third, explanation prompts focus effort on particular aspects of the to-be-learned material, potentially drawing effort away from other important information. Explanation prompts must be carefully designed to align with target learning outcomes. Fourth, prompted self-explanation often promotes learning better than unguided studying, but alternative instructional techniques may be more effective under some conditions. Attention to these constraints should optimize the effectiveness of self-explanation as an instructional technique in future research and practice.

  3. Great Explanations: Opinionated Explanations for Recommendation

    OpenAIRE

    Muhammad, Khalil; Lawlor, Aonghus; Rafter, Rachael; Smyth, Barry

    2015-01-01

    Explaining recommendations helps users to make better, more satisfying decisions. We describe a novel approach to explanation for recommender systems, one that drives the recommendation process, while at the same time providing the user with useful insights into the reason why items have been chosen and the trade-os they may need to consider when making their choice. We describe this approach in the context ofa case-based recommender system that harnesses opinions mined from user-generated re...

  4. Neurophysiology of the "Celiac Brain": Disentangling Gut-Brain Connections.

    Science.gov (United States)

    Pennisi, Manuela; Bramanti, Alessia; Cantone, Mariagiovanna; Pennisi, Giovanni; Bella, Rita; Lanza, Giuseppe

    2017-01-01

    Celiac disease (CD) can be considered a complex multi-organ disorder with highly variable extra-intestinal, including neurological, involvement. Cerebellar ataxia, peripheral neuropathy, seizures, headache, cognitive impairment, and neuropsychiatric diseases are complications frequently reported. These manifestations may be present at the onset of the typical disease or become clinically evident during its course. However, CD subjects with subclinical neurological involvement have also been described, as well as patients with clear central and/or peripheral nervous system and intestinal histopathological disease features in the absence of typical CD manifestations. Based on these considerations, a sensitive and specific diagnostic method that is able to detect early disease process, progression, and complications is desirable. In this context, neurophysiological techniques play a crucial role in the non-invasive assessment of central nervous system (CNS) excitability and conductivity. Moreover, some of these tools are known for their valuable role in early diagnosis and follow-up of several neurological diseases or systemic disorders, such as CD with nervous system involvement, even at the subclinical level. This review provides an up-to-date summary of the neurophysiological basis of CD using electroencephalography (EEG), multimodal evoked potentials, and transcranial magnetic stimulation (TMS). The evidence examined here seems to converge on an overall profile of "hyperexcitable celiac brain," which partially recovers after institution of a gluten-free diet (GFD). The main translational correlate is that in case of subclinical neurological involvement or overt unexplained symptoms, neurophysiology could contribute to the diagnosis, assessment, and monitoring of a potentially underlying CD.

  5. [Intraoperative neurophysiological monitoring in Spain: its beginnings, current situation and future prospects].

    Science.gov (United States)

    Cortes-Donate, V E; Perez-Lorensu, P J; Garcia-Garcia, A; Asociacion de Monitorizacion Intraquirurgica Neurofisiologica Espanola Amine, Asociacion de Monitorizacion Intraquirurgica Neurofisiologica Espanola Amine; Sociedad Espanola de Neurofisiologia Clinica Senfc, Sociedad Espanola de Neurofisiologia Clinica Senfc; Grupo de Trabajo de Monitorizacion Neurofisiologica Intraoperatoria de la Senfc, Grupo de Trabajo de Monitorizacion Neurofisiologica Intraoperatoria de la Senfc

    2018-05-01

    Intraoperative neurophysiological monitoring (IONM) is nowadays another tool within the operating room that seeks to avoid neurological sequels derived from the surgical act. The Spanish Neurophysiological Intra-Surgical Monitoring Association (AMINE) in collaboration with the Spanish Society of Clinical Neurophysiology (SENFC), and the IONM Working Group of the SENFC has been collecting data in order to know the current situation of the IONM in Spain by hospitals, autonomous communities including the autonomous cities of Ceuta and Melilla, the opinions of the specialists in clinical neurophysiology involved in this topic and further forecasts regarding IONM. The data was gathered from November 2015 to May 2016 through telephone contact and/or email with specialists in clinical neurophysiology of the public National Health System, and through a computerized survey that also includes private healthcare centers. With the data obtained, from the perspective of AMINE and the SENFC we consider that nowadays the field of medicine covered by IONM is considerably large and it is foreseen that it will continue to grow. Therefore, a greater number of specialists in Clinical Neurophysiology will be required, as well as the need for specific training within the specialty that involves increasing the training period of MIRs based on competencies due to the increase in techniques/procedures, as well as its complexity.

  6. Constructing Scientific Explanations: a System of Analysis for Students' Explanations

    Science.gov (United States)

    de Andrade, Vanessa; Freire, Sofia; Baptista, Mónica

    2017-08-01

    This article describes a system of analysis aimed at characterizing students' scientific explanations. Science education literature and reform documents have been highlighting the importance of scientific explanations for students' conceptual understanding and for their understanding of the nature of scientific knowledge. Nevertheless, and despite general agreement regarding the potential of having students construct their own explanations, a consensual notion of scientific explanation has still not been reached. As a result, within science education literature, there are several frameworks defining scientific explanations, with different foci as well as different notions of what accounts as a good explanation. Considering this, and based on a more ample project, we developed a system of analysis to characterize students' explanations. It was conceptualized and developed based on theories and models of scientific explanations, science education literature, and from examples of students' explanations collected by an open-ended questionnaire. With this paper, it is our goal to present the system of analysis, illustrating it with specific examples of students' collected explanations. In addition, we expect to point out its adequacy and utility for analyzing and characterizing students' scientific explanations as well as for tracing their progression.

  7. Sequential and simultaneous multiple explanation

    Directory of Open Access Journals (Sweden)

    Robert Litchfield

    2007-02-01

    Full Text Available This paper reports two experiments comparing variants of multiple explanation applied in the early stages of a judgment task (a case involving employee theft where participants are not given a menu of response options. Because prior research has focused on situations where response options are provided to judges, we identify relevant dependent variables that an intervention might affect when such options are not given. We use these variables to build a causal model of intervention that illustrates both the intended effects of multiple explanation and some potentially competing processes that it may trigger. Although multiple explanation clearly conveys some benefits (e.g., willingness to delay action to engage in information search, increased detail, quality and confidence in alternative explanations in the present experiments, we also found evidence that it may initiate or enhance processes that attenuate its advantages (e.g., feelings that one does not need more data if one has multiple good explanations.

  8. Handling Metadata in a Neurophysiology Laboratory

    Directory of Open Access Journals (Sweden)

    Lyuba Zehl

    2016-07-01

    Full Text Available To date, non-reproducibility of neurophysiological research is a matterof intense discussion in the scientific community. A crucial componentto enhance reproducibility is to comprehensively collect and storemetadata, that is all information about the experiment, the data,and the applied preprocessing steps on the data, such that they canbe accessed and shared in a consistent and simple manner. However,the complexity of experiments, the highly specialized analysis workflowsand a lack of knowledge on how to make use of supporting softwaretools often overburden researchers to perform such a detailed documentation.For this reason, the collected metadata are often incomplete, incomprehensiblefor outsiders or ambiguous. Based on our research experience in dealingwith diverse datasets, we here provide conceptual and technical guidanceto overcome the challenges associated with the collection, organization,and storage of metadata in a neurophysiology laboratory. Through theconcrete example of managing the metadata of a complex experimentthat yields multi-channel recordings from monkeys performing a behavioralmotor task, we practically demonstrate the implementation of theseapproaches and solutions with the intention that they may be generalizedto a specific project at hand. Moreover, we detail five use casesthat demonstrate the resulting benefits of constructing a well-organizedmetadata collection when processing or analyzing the recorded data,in particular when these are shared between laboratories in a modernscientific collaboration. Finally, we suggest an adaptable workflowto accumulate, structure and store metadata from different sourcesusing, by way of example, the odML metadata framework.

  9. Neurophysiology and neurochemistry of corticobasal syndrome.

    Science.gov (United States)

    Murgai, Aditya A; Jog, Mandar S

    2018-01-06

    Corticobasal syndrome is a rare neurodegenerative disorder, which presents with a progressive, asymmetrical, akinetic rigid syndrome and early cortical signs. However, clinical, pathological, and electrophysiological heterogeneity makes the understanding of this syndrome challenging. Corticobasal syndrome can have various pathological substrates including corticobasal degeneration, Alzheimer's disease, Fronto-temporal degeneration with TDP inclusions, Creutzfeldt-Jakob disease, and progressive supranuclear palsy (PSP). Furthermore, tools such as transcranial magnetic stimulation (TMS) and functional neuroimaging techniques like PET and SPECT have not been adequately used to supplement the clinico-pathological heterogeneity. TMS studies in CBS have revealed changes in cortical excitability and transcortical inhibition. Despite the availability of more than 2 decades, its potential in CBS has not been fully utilized in studying the cortical plasticity and effect of Levodopa on central neurophysiology. PET and SPECT studies in CBS have shown abnormalities in regional glucose metabolism, asymmetrical involvement of presynaptic dopaminergic system, and ascending cholinergic connections to the cortex. While most studies have shown normal D2 receptor-binding activity in striatum of CBS cases, the results have not been unanimous. Functional neuroimaging and TMS studies in CBS have shown the involvement of GABAergic, muscarinic, and dopaminergic systems. In this review, we aim to provide the current state of understanding of central neurophysiology and neurochemistry of CBS using TMS and functional neuroimaging techniques. We also highlight the heterogeneous nature of this disorder and the existing knowledge gaps.

  10. The neurophysiology of sexual arousal.

    Science.gov (United States)

    Schober, Justine M; Pfaff, Donald

    2007-09-01

    Our understanding of the process and initiation of sexual arousal is being enhanced by both animal and human studies, inclusive of basic science principles and research on clinical outcomes. Sexual arousal is dependent on neural (sensory and cognitive) factors, hormonal factors, genetic factors and, in the human case, the complex influences of culture and context. Sexual arousal activates the cognitive and physiologic processes that can eventually lead to sexual behavior. Sexual arousal comprises a particular subset of central nervous system arousal functions which depend on primitive, fundamental arousal mechanisms that cause generalized brain activity, but are manifest in a sociosexual context. The neurophysiology of sexual arousal is seen as a bidirectional system universal to all vertebrates. The following review includes known neural and genomic mechanisms of a hormone-dependent circuit for simple sex behavior. New information about hormone effects on causal steps related to sex hormones' nuclear receptor isoforms expressed by hypothalamic neurons continues to enrich our understanding of this neurophysiology.

  11. Examining elementary teachers' knowledge and instruction of scientific explanations for fostering children's explanations in science

    Science.gov (United States)

    Wiebke, Heidi Lynn

    This study employed an embedded mixed methods multi-case study design (Creswell, 2014) with six early childhood (grades K-2) teachers to examine a) what changes occurred to their subject matter knowledge (SMK) and pedagogical content knowledge (PCK) for teaching scientific explanations while participating in a professional development program, b) how they planned for and implemented scientific explanation instruction within a teacher developed unit on properties of matter, and c) what affordances their instruction of scientific explanations had on fostering their students' abilities to generate explanations in science. Several quantitative and qualitative measures were collected and analyzed in accordance to this studies conceptual framework, which consisted of ten instructional practices teachers should consider assimilating or accommodating into their knowledge base (i.e., SMK & PCK) for teaching scientific explanations. Results of this study indicate there was little to no positive change in the teachers' substantive and syntactic SMK. However, all six teachers did make significant changes to all five components of their PCK for teaching explanations in science. While planning for scientific explanation instruction, all six teachers' contributed some ideas for how to incorporate seven of the ten instructional practices for scientific explanations within the properties of matter unit they co-developed. When enacting the unit, the six teachers' employed seven to nine of the instructional practices to varying levels of effectiveness, as measured by researcher developed rubrics. Given the six teachers' scientific explanation instruction, many students did show improvement in their ability to formulate a scientific explanation, particularly their ability to provide multiple pieces of evidence. Implications for professional developers, teacher educators, researchers, policy makers, and elementary teachers regarding how to prepare teachers for and support students

  12. The fractal geometry of nutrient exchange surfaces does not provide an explanation for 3/4-power metabolic scaling

    Directory of Open Access Journals (Sweden)

    Painter Page R

    2005-08-01

    Full Text Available Abstract Background A prominent theoretical explanation for 3/4-power allometric scaling of metabolism proposes that the nutrient exchange surface of capillaries has properties of a space-filling fractal. The theory assumes that nutrient exchange surface area has a fractal dimension equal to or greater than 2 and less than or equal to 3 and that the volume filled by the exchange surface area has a fractal dimension equal to or greater than 3 and less than or equal to 4. Results It is shown that contradicting predictions can be derived from the assumptions of the model. When errors in the model are corrected, it is shown to predict that metabolic rate is proportional to body mass (proportional scaling. Conclusion The presence of space-filling fractal nutrient exchange surfaces does not provide a satisfactory explanation for 3/4-power metabolic rate scaling.

  13. Neurophysiological basis of creativity in healthy elderly people: a multiscale entropy approach.

    Science.gov (United States)

    Ueno, Kanji; Takahashi, Tetsuya; Takahashi, Koichi; Mizukami, Kimiko; Tanaka, Yuji; Wada, Yuji

    2015-03-01

    Creativity, which presumably involves various connections within and across different neural networks, reportedly underpins the mental well-being of older adults. Multiscale entropy (MSE) can characterize the complexity inherent in EEG dynamics with multiple temporal scales. It can therefore provide useful insight into neural networks. Given that background, we sought to clarify the neurophysiological bases of creativity in healthy elderly subjects by assessing EEG complexity with MSE, with emphasis on assessment of neural networks. We recorded resting state EEG of 20 healthy elderly subjects. MSE was calculated for each subject for continuous 20-s epochs. Their relevance to individual creativity was examined concurrently with intellectual function. Higher individual creativity was linked closely to increased EEG complexity across higher temporal scales, but no significant relation was found with intellectual function (IQ score). Considering the general "loss of complexity" theory of aging, our finding of increased EEG complexity in elderly people with heightened creativity supports the idea that creativity is associated with activated neural networks. Results reported here underscore the potential usefulness of MSE analysis for characterizing the neurophysiological bases of elderly people with heightened creativity. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  14. Neurophysiological symptoms and aspartame: What is the connection?

    Science.gov (United States)

    Choudhary, Arbind Kumar; Lee, Yeong Yeh

    2018-06-01

    Aspartame (α-aspartyl-l-phenylalanine-o-methyl ester), an artificial sweetener, has been linked to behavioral and cognitive problems. Possible neurophysiological symptoms include learning problems, headache, seizure, migraines, irritable moods, anxiety, depression, and insomnia. The consumption of aspartame, unlike dietary protein, can elevate the levels of phenylalanine and aspartic acid in the brain. These compounds can inhibit the synthesis and release of neurotransmitters, dopamine, norepinephrine, and serotonin, which are known regulators of neurophysiological activity. Aspartame acts as a chemical stressor by elevating plasma cortisol levels and causing the production of excess free radicals. High cortisol levels and excess free radicals may increase the brains vulnerability to oxidative stress which may have adverse effects on neurobehavioral health. We reviewed studies linking neurophysiological symptoms to aspartame usage and conclude that aspartame may be responsible for adverse neurobehavioral health outcomes. Aspartame consumption needs to be approached with caution due to the possible effects on neurobehavioral health. Whether aspartame and its metabolites are safe for general consumption is still debatable due to a lack of consistent data. More research evaluating the neurobehavioral effects of aspartame are required.

  15. Kinds and problems of geomorphological explanation

    Science.gov (United States)

    Cox, Nicholas J.

    2007-07-01

    What characterises satisfactory explanations in geomorphology is a key methodological question deserving continued analysis. In turn it raises the issue of the role played by methodology within the science. At its best, methodology can provide helpful distinctions, identify key issues and yield guidance for researchers. The substantive context for debates on explanation is the apparent complexity and difficulty of geomorphology as a science, which is arguably no greater than that of other Earth or environmental sciences. The logical view of explanation dominant in the 1950s and 1960s still has value, but a broader view is needed of explanations, related to the questions geomorphologists (and others) ask and to the answers that they find interesting. Answers may be sought in terms of purpose, history, mechanisms and statistics. Arguments over what is supposed to be reductionism can be clarified by underlining that both micro- and macro-explanations may be helpful. Although many geomorphologists aspire to mechanistic explanations, they often stop short at statistical explanations, making use of convenient functional forms such as power laws. Explanations have both social and psychological dimensions, the former much stressed in history of science and recent science studies, the latter deserving greater emphasis at present. Complicated models raise the question of how far it can be said that geomorphologists understand them in totality. A bestiary of poor explanations is needed, so that geomorphologists are not seduced by weak arguments and because they often serve as steps towards better explanations. Circular arguments, ad hoc explanations, and mistaking the name of the problem for the solution are cases in point.

  16. Neurophysiological Based Methods of Guided Image Search

    National Research Council Canada - National Science Library

    Marchak, Frank

    2003-01-01

    .... We developed a model of visual feature detection, the Neuronal Synchrony Model, based on neurophysiological models of temporal neuronal processing, to improve the accuracy of automatic detection...

  17. Pygopagus Conjoined Twins: A Neurophysiologic Intraoperative Monitoring Schema.

    Science.gov (United States)

    Cromeens, Barrett P; McKinney, Jennifer L; Leonard, Jeffrey R; Governale, Lance S; Brown, Judy L; Henry, Christina M; Levitt, Marc A; Wood, Richard J; Besner, Gail E; Islam, Monica P

    2017-03-01

    Conjoined twins occur in up to 1 in 50,000 live births with approximately 18% joined in a pygopagus configuration at the buttocks. Twins with this configuration display symptoms and carry surgical risks during separation related to the extent of their connection which can include anorectal, genitourinary, vertebral, and neural structures. Neurophysiologic intraoperative monitoring for these cases has been discussed in the literature with variable utility. The authors present a case of pygopagus twins with fused spinal cords and imperforate anus where the use of neurophysiologic intraoperative monitoring significantly impacted surgical decision-making in division of these critical structures.

  18. Intraoperative neurophysiological monitoring for the anaesthetist ...

    African Journals Online (AJOL)

    Intraoperative neurophysiological monitoring (IONM) has become the gold standard for the monitoring of functional nervous tissue and mapping of eloquent brain tissue during neurosurgical procedures. The multimodal use of somatosensory-evoked potentials and motor-evoked potentials ensures adequate monitoring of ...

  19. Axis: Generating Explanations at Scale with Learnersourcing and Machine Learning

    Science.gov (United States)

    Williams, Joseph Jay; Kim, Juho; Rafferty, Anna; Heffernan, Neil; Maldonado, Samuel; Gajos, Krzysztof Z.; Lasecki, Walter S.; Heffernan, Neil

    2016-01-01

    While explanations may help people learn by providing information about why an answer is correct, many problems on online platforms lack high-quality explanations. This paper presents AXIS (Adaptive eXplanation Improvement System), a system for obtaining explanations. AXIS asks learners to generate, revise, and evaluate explanations as they solve…

  20. Descartes' visit to the town library, or how Augustinian is Descartes' neurophysiology?

    Science.gov (United States)

    Smith, C U

    1998-08-01

    Rene Descartes was early accused of taking his central philosophical proposition from St Augustine. Did he also take his central neurophysiological concept from the same source? This is the question which this paper sets out to answer. It is concluded that the foundational neurophysiology propounded in L'Homme does indeed show strong and interesting resemblences to Augustine's largely Erasistratean version. Descartes, however, working within the new paradigm of seventeenth-century physical science, introduced a new principle: whereas Augustine's neurophysiology is pervaded throughout by a vital factor, the pneuma, Descartes' theory involved only inanimate material forces. It is concluded, further, that in spite of the interesting similarities between Augustinian and Cartesian neurophysiology there is no evidence for any direct plagiarism. It seems more likely that Augustine's influence was filtered through the Galenical physiologists of Descartes' own time and of the preceding century.

  1. Neurophysiology of the “Celiac Brain”: Disentangling Gut-Brain Connections

    Directory of Open Access Journals (Sweden)

    Manuela Pennisi

    2017-09-01

    Full Text Available Celiac disease (CD can be considered a complex multi-organ disorder with highly variable extra-intestinal, including neurological, involvement. Cerebellar ataxia, peripheral neuropathy, seizures, headache, cognitive impairment, and neuropsychiatric diseases are complications frequently reported. These manifestations may be present at the onset of the typical disease or become clinically evident during its course. However, CD subjects with subclinical neurological involvement have also been described, as well as patients with clear central and/or peripheral nervous system and intestinal histopathological disease features in the absence of typical CD manifestations. Based on these considerations, a sensitive and specific diagnostic method that is able to detect early disease process, progression, and complications is desirable. In this context, neurophysiological techniques play a crucial role in the non-invasive assessment of central nervous system (CNS excitability and conductivity. Moreover, some of these tools are known for their valuable role in early diagnosis and follow-up of several neurological diseases or systemic disorders, such as CD with nervous system involvement, even at the subclinical level. This review provides an up-to-date summary of the neurophysiological basis of CD using electroencephalography (EEG, multimodal evoked potentials, and transcranial magnetic stimulation (TMS. The evidence examined here seems to converge on an overall profile of “hyperexcitable celiac brain,” which partially recovers after institution of a gluten-free diet (GFD. The main translational correlate is that in case of subclinical neurological involvement or overt unexplained symptoms, neurophysiology could contribute to the diagnosis, assessment, and monitoring of a potentially underlying CD.

  2. Benefit of neurophysiologic monitoring for pediatric cardiac surgery.

    Science.gov (United States)

    Austin, E H; Edmonds, H L; Auden, S M; Seremet, V; Niznik, G; Sehic, A; Sowell, M K; Cheppo, C D; Corlett, K M

    1997-11-01

    Pediatric patients undergoing repair of congenital cardiac abnormalities have a significant risk of an adverse neurologic event. Therefore this retrospective cohort study examined the potential benefit of interventions based on intraoperative neurophysiologic monitoring in decreasing both postoperative neurologic sequelae and length of hospital stay as a cost proxy. With informed parental consent approved by the institutional review board, electroencephalography, transcranial Doppler ultrasonic measurement of middle cerebral artery blood flow velocity, and transcranial near-infrared cerebral oximetry were monitored in 250 patients. An interventional algorithm was used to detect and correct specific deficiencies in cerebral perfusion or oxygenation or to increase cerebral tolerance to ischemia or hypoxia. Noteworthy changes in brain perfusion or metabolism were observed in 176 of 250 (70%) patients. Intervention that altered patient management was initially deemed appropriate in 130 of 176 (74%) patients with neurophysiologic changes. Obvious neurologic sequelae (i.e., seizure, movement, vision or speech disorder) occurred in five of 74 (7%) patients without noteworthy change, seven of 130 (6%) patients with intervention, and 12 of 46 (26%) patients without intervention (p = 0.001). Survivors' median length of stay was 6 days in the no-change and intervention groups but 9 days in the no-intervention group. In addition, the percentage of patients in the no-intervention group discharged from the hospital within 1 week (32%) was significantly less than that in either the intervention (51%, p = 0.05) or no-change (58%, p = 0.01) groups. On the basis of an estimated hospital neurologic complication cost of $1500 per day, break-even analysis justified a hospital expenditure for neurophysiologic monitoring of $2142 per case. Interventions based on neurophysiologic monitoring appear to decrease the incidence of postoperative neurologic sequelae and reduce the length of stay

  3. The many roles of "explanation" in science education: a case study

    Science.gov (United States)

    Rocksén, Miranda

    2016-12-01

    In this paper the role of explanations is discussed in relation to possible consequences originating in the polysemy of the word explanation. The present study is a response to conceptual confusions that have arisen in the intersection between theory and practice, and between science education literature and communication in authentic science classroom settings. Science classroom communication is examined in terms of one teacher's word use during eleven lessons about evolution. The study contributes empirical examples of how disciplinary norms of valid explanations are manifested in science classroom communication. A dialogical analysis shows how the teacher provides three conversational structures: asking for acts of explanation, providing opportunities to talk about what explanations are in this context and providing opportunities to talk about explanations constructed by students. These three structures facilitate the process of learning how to evaluate and justify explanations. Three potential meanings of the word "explanation" are pointed to: an everyday meaning, a pedagogical-professional meaning and a scientific meaning of the word. It is suggested that the co-existence of these three potential meanings has communicative consequences in science education.

  4. Detectability of Granger causality for subsampled continuous-time neurophysiological processes.

    Science.gov (United States)

    Barnett, Lionel; Seth, Anil K

    2017-01-01

    Granger causality is well established within the neurosciences for inference of directed functional connectivity from neurophysiological data. These data usually consist of time series which subsample a continuous-time biophysiological process. While it is well known that subsampling can lead to imputation of spurious causal connections where none exist, less is known about the effects of subsampling on the ability to reliably detect causal connections which do exist. We present a theoretical analysis of the effects of subsampling on Granger-causal inference. Neurophysiological processes typically feature signal propagation delays on multiple time scales; accordingly, we base our analysis on a distributed-lag, continuous-time stochastic model, and consider Granger causality in continuous time at finite prediction horizons. Via exact analytical solutions, we identify relationships among sampling frequency, underlying causal time scales and detectability of causalities. We reveal complex interactions between the time scale(s) of neural signal propagation and sampling frequency. We demonstrate that detectability decays exponentially as the sample time interval increases beyond causal delay times, identify detectability "black spots" and "sweet spots", and show that downsampling may potentially improve detectability. We also demonstrate that the invariance of Granger causality under causal, invertible filtering fails at finite prediction horizons, with particular implications for inference of Granger causality from fMRI data. Our analysis emphasises that sampling rates for causal analysis of neurophysiological time series should be informed by domain-specific time scales, and that state-space modelling should be preferred to purely autoregressive modelling. On the basis of a very general model that captures the structure of neurophysiological processes, we are able to help identify confounds, and offer practical insights, for successful detection of causal connectivity

  5. HANSENS DISEASE : STUDY OF CLINICAL, NEUROPATHOLOGICAL, NEUROPHYSIOLOGICAL PATTERN OF LEPROUS NEUROPATHY

    OpenAIRE

    Vijay Kumar; Ajay Kumar

    2015-01-01

    A need still exists to determine the clinical and neurophysiological characteristics of leprosy neuropathy at distinct times of the disease by different methods that measure the various nerve fiber functions. A prospective clinical study was performed 100 patients of clinically proven Hansen’s will take in study and given diagnosis is made by dermatologist and neurologist. For Study of Clinical, Neuropathological , Neurophysiological Pattern of leprous neuropathy and r...

  6. Basics of neuroanatomy and neurophysiology.

    Science.gov (United States)

    Barha, C K; Nagamatsu, L S; Liu-Ambrose, T

    2016-01-01

    This chapter presents an overview of the anatomy and functioning of the central nervous system. We begin the discussion by first examining the cellular basis of neural transmission. Then we present a brief description of the brain's white and gray matter and associated diseases, including a discussion of white-matter lesions. Finally, we place this information into context by discussing how the central nervous system integrates complex information to guide key functional systems, including the visual, auditory, chemosensory, somatic, limbic, motor, and autonomic systems. Where appropriate, we have supplied information pertaining to pathologic and functional outcomes of damage to the central nervous system. Also included is a brief description of important tools and methods used in the study of neuroanatomy and neurophysiology. Overall, this chapter provides a basic review of the concepts required to understand and interpret the clinical disorders and related material presented in the subsequent chapters of this book. © 2016 Elsevier B.V. All rights reserved.

  7. Neurophysiologic Correlates of Post-Stroke Mood and Emotional Control

    Directory of Open Access Journals (Sweden)

    Deniz Doruk

    2016-08-01

    Full Text Available Objective: Emotional disturbance is a common complication of stroke significantly affecting functional recovery and quality of life. Identifying relevant neurophysiologic markers associated with post-stroke emotional disturbance may lead to a better understanding of this disabling condition, guiding the diagnosis, development of new interventions and the assessments of treatment response. Methods: Thirty-five subjects with chronic stroke were enrolled in this study. The emotion sub-domain of Stroke Impact Scale (SIS-Emotion was used to assess post-stroke mood and emotional control. The relation between SIS-Emotion and neurophysiologic measures was assessed by using covariance mapping and univariate linear regression. Multivariate analyses were conducted to identify and adjust for potential confounders. Neurophysiologic measures included power asymmetry and coherence assessed by electroencephalography (EEG; and motor threshold, intracortical inhibition (ICI and intracortical facilitation (ICF measured by transcranial magnetic stimulation (TMS. Results: Lower scores on SIS-Emotion was associated with 1 frontal EEG power asymmetry in alpha and beta bands, 2 central EEG power asymmetry in alpha and theta bands, and 3 lower inter-hemispheric coherence over frontal and central areas in alpha band. SIS-Emotion also correlated with higher ICF and MT in the unlesioned hemisphere as measured by TMS. Conclusions: To our knowledge, this is the first study using EEG and TMS to index neurophysiologic changes associated with post-stroke mood and emotional control. Our results suggest that inter-hemispheric imbalance measured by EEG power and coherence, as well as an increased intracortical facilitation in the unlesioned hemisphere measured by TMS might be relevant markers associated with post-stroke mood and emotional control which can guide future studies investigating new diagnostic and treatment modalities in stroke rehabilitation.

  8. Memory formation during anaesthesia: plausibility of a neurophysiological basis

    Science.gov (United States)

    Veselis, R. A.

    2015-01-01

    As opposed to conscious, personally relevant (explicit) memories that we can recall at will, implicit (unconscious) memories are prototypical of ‘hidden’ memory; memories that exist, but that we do not know we possess. Nevertheless, our behaviour can be affected by these memories; in fact, these memories allow us to function in an ever-changing world. It is still unclear from behavioural studies whether similar memories can be formed during anaesthesia. Thus, a relevant question is whether implicit memory formation is a realistic possibility during anaesthesia, considering the underlying neurophysiology. A different conceptualization of memory taxonomy is presented, the serial parallel independent model of Tulving, which focuses on dynamic information processing with interactions among different memory systems rather than static classification of different types of memories. The neurophysiological basis for subliminal information processing is considered in the context of brain function as embodied in network interactions. Function of sensory cortices and thalamic activity during anaesthesia are reviewed. The role of sensory and perisensory cortices, in particular the auditory cortex, in support of memory function is discussed. Although improbable, with the current knowledge of neurophysiology one cannot rule out the possibility of memory formation during anaesthesia. PMID:25735711

  9. Reward mechanisms in the brain and their role in dependence : evidence from neurophysiological and neuroimaging studies

    NARCIS (Netherlands)

    Martin-Soelch, C; Leenders, KL; Chevalley, AF; Missimer, J; Kunig, G; Magyar, S; Mino, A; Schultz, W

    2001-01-01

    This article reviews neuronal activity related to reward processing in primate and human brains. In the primate brain, neurophysiological methods provide a differentiated view of reward processing in a limited number of brain structures. Dopamine neurons respond to unpredictable rewards and produce

  10. Neurophysiological Markers of Emotion Processing in Burnout Syndrome.

    Science.gov (United States)

    Golonka, Krystyna; Mojsa-Kaja, Justyna; Popiel, Katarzyna; Marek, Tadeusz; Gawlowska, Magda

    2017-01-01

    The substantial body of research employing subjective measures indicates that burnout syndrome is associated with cognitive and emotional dysfunctions. The growing amount of neurophysiological and neuroimaging research helps in broadening existing knowledge of the neural mechanisms underlying core burnout components (emotional exhaustion and depersonalization/cynicism) that are inextricably associated with emotional processing. In the presented EEG study, a group of 93 participants (55 women; mean age = 35.8) were selected for the burnout group or the demographically matched control group on the basis of the results of the Maslach Burnout Inventory - General Survey (MBI-GS) and the Areas of Worklife Survey (AWS). Subjects then participated in an EEG experiment using two experimental procedures: a facial recognition task and viewing of passive pictures. The study focuses on analyzing event-related potentials (ERPs): N170, VPP, EPN, and LPP, as indicators of emotional information processing. Our results show that burnout subjects, as compared to the control group, demonstrate significantly weaker response to affect-evoking stimuli, indexed by a decline in VPP amplitude to emotional faces and decreased EPN amplitude in processing emotional scenes. The analysis of N170 and LPP showed no significant between-group difference. The correlation analyses revealed that VPP and EPN, which are ERP components related to emotional processing, are associated with two core burnout symptoms: emotional exhaustion and cynicism. To our knowledge, we are one of the first research groups to use ERPs to demonstrate such a relationship between neurophysiological activity and burnout syndrome in the context of emotional processing. Thus, in conclusion we emphasized that the decreased amplitude of VPP and EPN components in the burnout group may be a neurophysiological manifestation of emotional blunting and may be considered as neurophysiological markers of emotional exhaustion and cynicism

  11. Neurophysiology Summary

    Science.gov (United States)

    Paloski, William H.

    2001-01-01

    The terrestrial gravitational field serves as an important orientation reference for human perception and movement, being continually monitored by sensory receptors in the skin, muscles, joints, and vestibular otolith organs. Cues from these graviceptors are used by the brain to estimate spatial orientation and to control balance and movement. Changes in these cues associated with the tonic changes in gravity (gravito-inertial force),during the launch and entry phases of space flight missions result in altered perceptions, degraded motor control performance, and in some cases, "motion" sickness during, and for a period of time after, the g-transitions. In response to these transitions, however, physiological and behavioral response mechanisms are triggered to compensate for altered graviceptor cues and/or to adapt to the new sensory environment. Basic research in the neurophysiology discipline is focused on understanding the characteristic features of and the underlying mechanisms for the normal human response to tonic changes in the gravito-inertial force environment. These studies address fundamental questions regarding the role of graviceptors in orientation and movement in the terrestrial environment, as well as the capacity, specificity, and modes for neural plasticity in the sensory-motor and perceptual systems of the brain. At the 2001 workshop basic research studies were presented addressing: neuroanatomical responses to altered gravity environments, the neural mechanisms for resolving the ambiguity between tilting and translational stimuli in otolith organ sensory input, interactions between the vestibular system and the autonomic nervous system , the roles of haptic and visual cues in spatial orientation, mechanisms for training environment-appropriate sensorimotor responses triggered by environment-specific context cues, and studies of sensori-motor control of posture and locomotion in the terrestrial environment with and without recent exposure to space

  12. Re-orienting discussions of scientific explanation: A functional perspective.

    Science.gov (United States)

    Woody, Andrea I

    2015-08-01

    Philosophy of science offers a rich lineage of analysis concerning the nature of scientific explanation, but the vast majority of this work, aiming to provide an analysis of the relation that binds a given explanans to its corresponding explanandum, presumes the proper analytic focus rests at the level of individual explanations. There are, however, other questions we could ask about explanation in science, such as: What role(s) does explanatory practice play in science? Shifting focus away from explanations, as achievements, toward explaining, as a coordinated activity of communities, the functional perspective aims to reveal how the practice of explanatory discourse functions within scientific communities given their more comprehensive aims and practices. In this paper, I outline the functional perspective, argue that taking the functional perspective can reveal important methodological roles for explanation in science, and consequently, that beginning here provides resources for developing more adequate responses to traditional concerns. In particular, through an examination of the ideal gas law, I emphasize the normative status of explanations within scientific communities and discuss how such status underwrites a compelling rationale for explanatory power as a theoretical virtue. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Analysis of 1014 consecutive operative cases to determine the utility of intraoperative neurophysiological data

    OpenAIRE

    Hussain, Namath Syed

    2015-01-01

    Introduction: Intraoperative neurophysiological monitoring (IOM) during neurosurgical procedures has become the standard of care at tertiary care medical centers. While prospective data regarding the clinical utility of IOM are conspicuously lacking, retrospective analyses continue to provide useful information regarding surgeon responses to reported waveform changes. Methods: Data regarding clinical presentation, operative course, IOM, and postoperative neurological examination were compiled...

  14. Foot Drop: Looking Beyond Common Peroneal Nerve Palsy – A Neurophysiology Centre Experience

    LENUS (Irish Health Repository)

    Yap, SM

    2016-04-01

    Foot drop is a complex symptom with a considerable range in aetiology, severity and prognosis. We aim to characterise the aetiologies of foot drop and assess the diagnostic contribution of neurophysiologic testing (NCS\\/EMG). Retrospective review of consecutive referrals of foot drop to the Neurophysiology Department in Cork University Hospital was performed over a two year period (January 2012 to December 2013). Of a total of 59 referrals, common peroneal nerve (CPN) palsy comprised only slightly more than half of cases; 3(5%) have central origin; 3(5%) have motor neuron disease. Six (10%) have diabetes; 7(12%) have cancer; 5(8%) were bilateral. NCS\\/EMG altered initial working diagnosis in 14 out of 52 (27%) cases whereby initial diagnosis was provided. However one-third of all cases revealed additional coexistent pathology in an anatomic location remote to that of the primary diagnosis. Foot drop with central and proximal localisations are important and under recognised. NCS\\/EMG is valuable and also reveals additional pathology which warrants investigation

  15. Self-Explanation and Explanatory Feedback in Games: Individual Differences, Gameplay, and Learning

    Science.gov (United States)

    Killingsworth, Stephen S.; Clark, Douglas B.; Adams, Deanne M.

    2015-01-01

    Previous research has demonstrated the efficacy of two explanation-based approaches for increasing learning in educational games. The first involves asking students to explain their answers (self-explanation) and the second involves providing correct explanations (explanatory feedback). This study (1) compared self-explanation and explanatory…

  16. Resting-State Neurophysiological Activity Patterns in Young People with ASD, ADHD, and ASD + ADHD

    Science.gov (United States)

    Shephard, Elizabeth; Tye, Charlotte; Ashwood, Karen L.; Azadi, Bahar; Asherson, Philip; Bolton, Patrick F.; McLoughlin, Grainne

    2018-01-01

    Altered power of resting-state neurophysiological activity has been associated with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), which commonly co-occur. We compared resting-state neurophysiological power in children with ASD, ADHD, co-occurring ASD + ADHD, and typically developing controls. Children with ASD…

  17. Is the bias for function-based explanations culturally universal? Children from China endorse teleological explanations of natural phenomena

    Science.gov (United States)

    Schachner, Adena; Zhu, Liqi; Li, Jing; Kelemen, Deborah

    2017-01-01

    Young children in Western cultures tend to endorse teleological (function-based) explanations broadly across many domains, even when scientifically unwarranted. For instance, in contrast to Western adults, they explicitly endorse the idea that mountains were created for climbing, just like hats were created for warmth. Is this bias a product of culture, or a product of universal aspects of human cognition? In two studies, we explored whether adults and children in Mainland China, a highly secular, non-Western culture, show a bias for teleological explanations. When explaining both object properties (Exp. 1) and origins (Exp. 2), we found evidence that they do. While Chinese adults restricted teleological explanations to scientifically warranted cases, Chinese children endorsed them more broadly, extending them across different kinds of natural phenomena. This bias decreased with rising grade level across first, second and fourth grade. Overall, these data provide evidence that children’s bias for teleological explanations is not solely a product of Western Abrahamic cultures. Instead, it extends to other cultures including the East Asian secular culture of modern-day China. This suggests that the bias for function-based explanations may be driven by universal aspects of human cognition. PMID:28110152

  18. Children's success at detecting circular explanations and their interest in future learning.

    Science.gov (United States)

    Mills, Candice M; Danovitch, Judith H; Rowles, Sydney P; Campbell, Ian L

    2017-10-01

    These studies explore elementary-school-aged children's ability to evaluate circular explanations and whether they respond to receiving weak explanations by expressing interest in additional learning. In the first study, 6-, 8-, and 10-year-olds (n = 53) heard why questions about unfamiliar animals. For each question, they rated the quality of single explanations and later selected the best explanation between pairs of circular and noncircular explanations. When judging single explanations, 8- and 10-year-olds, and to some extent 6-year-olds, provided higher ratings for noncircular explanations compared to circular ones. When selecting between pairs of explanations, all age groups preferred noncircular explanations to circular ones, but older children did so more consistently than 6-year-olds. Children who recognized the weakness of the single circular explanations were more interested in receiving additional information about the question topics. In Study 2, all three age groups (n = 87) provided higher ratings for noncircular explanations compared to circular ones when listening to responses to how questions, but older children showed a greater distinction in their ratings than 6-year-olds. Moreover, the link between recognizing circular explanations as weak and interest in future learning could not be accounted for solely by individual differences in verbal intelligence. These findings illustrate the developmental trajectory of explanation evaluation and support that recognition of weak explanations is linked to interest in future learning across the elementary years. Implications for education are discussed.

  19. DNA methylation regulates neurophysiological spatial representation in memory formation

    Directory of Open Access Journals (Sweden)

    Eric D. Roth

    2015-04-01

    Full Text Available Epigenetic mechanisms including altered DNA methylation are critical for altered gene transcription subserving synaptic plasticity and the retention of learned behavior. Here, we tested the idea that one role for activity-dependent altered DNA methylation is stabilization of cognition-associated hippocampal place cell firing in response to novel place learning. We observed that a behavioral protocol (spatial exploration of a novel environment known to induce hippocampal place cell remapping resulted in alterations of hippocampal Bdnf DNA methylation. Further studies using neurophysiological in vivo single-unit recordings revealed that pharmacological manipulations of DNA methylation decreased long-term but not short-term place field stability. Together, our data highlight a role for DNA methylation in regulating neurophysiological spatial representation and memory formation.

  20. DNA methylation regulates neurophysiological spatial representation in memory formation.

    Science.gov (United States)

    Roth, Eric D; Roth, Tania L; Money, Kelli M; SenGupta, Sonda; Eason, Dawn E; Sweatt, J David

    2015-04-01

    Epigenetic mechanisms including altered DNA methylation are critical for altered gene transcription subserving synaptic plasticity and the retention of learned behavior. Here we tested the idea that one role for activity-dependent altered DNA methylation is stabilization of cognition-associated hippocampal place cell firing in response to novel place learning. We observed that a behavioral protocol (spatial exploration of a novel environment) known to induce hippocampal place cell remapping resulted in alterations of hippocampal Bdnf DNA methylation. Further studies using neurophysiological in vivo single unit recordings revealed that pharmacological manipulations of DNA methylation decreased long-term but not short-term place field stability. Together our data highlight a role for DNA methylation in regulating neurophysiological spatial representation and memory formation.

  1. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins

    OpenAIRE

    Camina, Eduardo; Güell, Francisco

    2017-01-01

    This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and...

  2. Sublime Views and Beautiful Explanations

    DEFF Research Database (Denmark)

    Barry, Daved; Meisiek, Stefan; Hatch, Mary Jo

    To create a generative theory that provides beautiful explanations and sublime views requires both a crafts and an art approach to scientific theorizing. The search for generativity leads scholars to perform various theorizing moves between the confines of simple, yet eloquent beauty...

  3. Memory formation during anaesthesia: plausibility of a neurophysiological basis.

    Science.gov (United States)

    Veselis, R A

    2015-07-01

    As opposed to conscious, personally relevant (explicit) memories that we can recall at will, implicit (unconscious) memories are prototypical of 'hidden' memory; memories that exist, but that we do not know we possess. Nevertheless, our behaviour can be affected by these memories; in fact, these memories allow us to function in an ever-changing world. It is still unclear from behavioural studies whether similar memories can be formed during anaesthesia. Thus, a relevant question is whether implicit memory formation is a realistic possibility during anaesthesia, considering the underlying neurophysiology. A different conceptualization of memory taxonomy is presented, the serial parallel independent model of Tulving, which focuses on dynamic information processing with interactions among different memory systems rather than static classification of different types of memories. The neurophysiological basis for subliminal information processing is considered in the context of brain function as embodied in network interactions. Function of sensory cortices and thalamic activity during anaesthesia are reviewed. The role of sensory and perisensory cortices, in particular the auditory cortex, in support of memory function is discussed. Although improbable, with the current knowledge of neurophysiology one cannot rule out the possibility of memory formation during anaesthesia. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. In private practice, informed consent is interpreted as providing explanations rather than offering choices: a qualitative study.

    Science.gov (United States)

    Delany, Clare M

    2007-01-01

    How do physiotherapists working in private practice understand and interpret the meaning and significance of informed consent in everyday clinical practice? Qualitative study using semi-structured interviews. Seventeen physiotherapists purposefully recruited from metropolitan private practices where treatment was on a one-on-one basis. Therapists defined informed consent as an implicit component of their routine clinical explanations, rather than a process of providing explicit patient choices. Therapists' primary concern was to provide information that led to a (therapist-determined) beneficial therapeutic outcome, rather than to enhance autonomous patient choice. Explicit patient choice and explicit informed consent were defined as important only if patients requested information or therapists recognised risks associated with the treatment. Physiotherapists defined informed consent within a context of achieving therapeutic outcomes rather than a context of respect for patient autonomy and autonomous choice. Physiotherapy practice guidelines developed to ensure compliance with ethical and legal obligations may therefore be followed only if they fit with therapists' understanding and interpretation of a desired therapeutic outcome.

  5. Experimental Philosophy of Explanation Rising: The Case for a Plurality of Concepts of Explanation.

    Science.gov (United States)

    Colombo, Matteo

    2017-03-01

    This paper brings together results from the philosophy and the psychology of explanation to argue that there are multiple concepts of explanation in human psychology. Specifically, it is shown that pluralism about explanation coheres with the multiplicity of models of explanation available in the philosophy of science, and it is supported by evidence from the psychology of explanatory judgment. Focusing on the case of a norm of explanatory power, the paper concludes by responding to the worry that if there is a plurality of concepts of explanation, one will not be able to normatively evaluate what counts as good explanation. Copyright © 2016 Cognitive Science Society, Inc.

  6. Neurophysiological correlates of embodiment and motivational factors during the perception of virtual architectural environments.

    Science.gov (United States)

    Vecchiato, Giovanni; Jelic, Andrea; Tieri, Gaetano; Maglione, Anton Giulio; De Matteis, Federico; Babiloni, Fabio

    2015-09-01

    The recent efforts aimed at providing neuroscientific explanations of how people perceive and experience architectural environments have largely justified the initial belief in the value of neuroscience for architecture. However, a systematic development of a coherent theoretical and experimental framework is missing. To investigate the neurophysiological reactions related to the appreciation of ambiances, we recorded the electroencephalographic (EEG) signals in an immersive virtual reality during the appreciation of interior designs. Such data have been analyzed according to the working hypothesis that appreciated environments involve embodied simulation mechanisms and circuits mediating approaching stimuli. EEG recordings of 12 healthy subjects have been performed during the perception of three-dimensional interiors that have been simulated in a CAVE system and judged according to dimensions of familiarity, novelty, comfort, pleasantness, arousal and presence. A correlation analysis on personal judgments returned that scores of novelty, pleasantness and comfort are positively correlated, while familiarity and novelty are in negative way. Statistical spectral maps reveal that pleasant, novel and comfortable interiors produce a de-synchronization of the mu rhythm over left sensorimotor areas. Interiors judged more pleasant and less familiar generate an activation of left frontal areas (theta and alpha bands), along an involvement of areas devoted to spatial navigation. An increase in comfort returns an enhancement of the theta frontal midline activity. Cerebral activations underlying appreciation of architecture could involve different mechanisms regulating corporeal, emotional and cognitive reactions. Therefore, it might be suggested that people's experience of architectural environments is intrinsically structured by the possibilities for action.

  7. Analogy, explanation, and proof

    Science.gov (United States)

    Hummel, John E.; Licato, John; Bringsjord, Selmer

    2014-01-01

    People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic) whose truth was not even known prior to the existence of the explanation (proof). What do the cognitive operations underlying the inference that the milk is sour have in common with the proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This seemingly small difference poses a challenge to the task of marshaling our understanding of analogical reasoning to understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence. PMID:25414655

  8. Analogy, Explanation, and Proof

    Directory of Open Access Journals (Sweden)

    John eHummel

    2014-11-01

    Full Text Available People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic whose truth was not even known prior to the existence of the explanation (proof. What do the cognitive operations underlying the (inductive inference that the milk is sour have in common with the (deductive proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This small-seeming difference poses a challenge to the task of marshaling our understanding of analogical reasoning in the service of understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence.

  9. Chronic alcoholism: insights from neurophysiology.

    Science.gov (United States)

    Campanella, S; Petit, G; Maurage, P; Kornreich, C; Verbanck, P; Noël, X

    2009-01-01

    Increasing knowledge of the anatomical structures and cellular processes underlying psychiatric disorders may help bridge the gap between clinical signs and basic physiological processes. Accordingly, considerable insight has been gained in recent years into a common psychiatric condition, i.e., chronic alcoholism. We reviewed various physiological parameters that are altered in chronic alcoholic patients compared to healthy individuals--continuous electroencephalogram, oculomotor measures, cognitive event-related potentials and event-related oscillations--to identify links between these physiological parameters, altered cognitive processes and specific clinical symptoms. Alcoholic patients display: (1) high beta and theta power in the resting electroencephalogram, suggesting hyperarousal of their central nervous system; (2) abnormalities in smooth pursuit eye movements, in saccadic inhibition during antisaccade tasks, and in prepulse inhibition, suggesting disturbed attention modulation and abnormal patterns of prefrontal activation that may stem from the same prefrontal "inhibitory" cortical dysfunction; (3) decreased amplitude for cognitive event-related potentials situated along the continuum of information-processing, suggesting that alcoholism is associated with neurophysiological deficits at the level of the sensory cortex and not only disturbances involving associative cortices and limbic structures; and (4) decreased theta, gamma and delta oscillations, suggesting cognitive disinhibition at a functional level. The heterogeneity of alcoholic disorders in terms of symptomatology, course and outcome is the result of various pathophysiological processes that physiological parameters may help to define. These alterations may be related to precise cognitive processes that could be easily monitored neurophysiologically in order to create more homogeneous subgroups of alcoholic individuals.

  10. Neurophysiological localisation of ulnar neuropathy at the elbow: Validation of diagnostic criteria developed by a taskforce of the Danish Society of clinical neurophysiology.

    Science.gov (United States)

    Pugdahl, K; Beniczky, S; Wanscher, B; Johnsen, B; Qerama, E; Ballegaard, M; Benedek, K; Juhl, A; Ööpik, M; Selmar, P; Sønderborg, J; Terney, D; Fuglsang-Frederiksen, A

    2017-11-01

    This study validates consensus criteria for localisation of ulnar neuropathy at elbow (UNE) developed by a taskforce of the Danish Society of Clinical Neurophysiology and compares them to the existing criteria from the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM). The Danish criteria are based on combinations of conduction slowing in the segments of the elbow and forearm expressed in Z-scores, and difference between the segments in m/s. Examining fibres to several muscles and sensory fibres can increase the certainty of the localisation. Diagnostic accuracy for UNE was evaluated on 181 neurophysiological studies of the ulnar nerve from 171 peer-reviewed patients from a mixed patient-group. The diagnostic reference standard was the consensus diagnosis based on all available clinical, laboratory, and electrodiagnostic information reached by a group of experienced Danish neurophysiologists. The Danish criteria had high specificity (98.4%) and positive predictive value (PPV) (95.2%) and fair sensitivity (76.9%). Compared to the AANEM criteria, the Danish criteria had higher specificity (p<0.001) and lower sensitivity (p=0.02). The Danish consensus criteria for UNE are very specific and have high PPV. The Danish criteria for UNE are reliable and well suited for use in different centres as they are based on Z-scores. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  11. Biomechanical correlates of symptomatic and asymptomatic neurophysiological impairment in high school football.

    Science.gov (United States)

    Breedlove, Evan L; Robinson, Meghan; Talavage, Thomas M; Morigaki, Katherine E; Yoruk, Umit; O'Keefe, Kyle; King, Jeff; Leverenz, Larry J; Gilger, Jeffrey W; Nauman, Eric A

    2012-04-30

    Concussion is a growing public health issue in the United States, and chronic traumatic encephalopathy (CTE) is the chief long-term concern linked to repeated concussions. Recently, attention has shifted toward subconcussive blows and the role they may play in the development of CTE. We recruited a cohort of high school football players for two seasons of observation. Acceleration sensors were placed in the helmets, and all contact activity was monitored. Pre-season computer-based neuropsychological tests and functional magnetic resonance imaging (fMRI) tests were also obtained in order to assess cognitive and neurophysiological health. In-season follow-up scans were then obtained both from individuals who had sustained a clinically-diagnosed concussion and those who had not. These changes were then related through stepwise regression to history of blows recorded throughout the football season up to the date of the scan. In addition to those subjects who had sustained a concussion, a substantial portion of our cohort who did not sustain concussions showed significant neurophysiological changes. Stepwise regression indicated significant relationships between the number of blows sustained by a subject and the ensuing neurophysiological change. Our findings reinforce the hypothesis that the effects of repetitive blows to the head are cumulative and that repeated exposure to subconcussive blows is connected to pathologically altered neurophysiology. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. EEG INTERFACE MODULE FOR COGNITIVE ASSESSMENT THROUGH NEUROPHYSIOLOGIC TESTS

    Directory of Open Access Journals (Sweden)

    Kundan Lal Verma

    2014-12-01

    Full Text Available The cognitive signal processing is one of the important interdisciplinary field came from areas of life sciences, psychology, psychiatry, engi-neering, mathematics, physics, statistics and many other fields of research. Neurophysiologic tests are utilized to assess and treat brain injury, dementia, neurological conditions, and useful to investigate psychological and psychiatric disorders. This paper presents an ongoing research work on development of EEG interface device based on the principles of cognitive assessments and instrumentation. The method proposed engineering and science of cogni-tive signal processing in case of brain computer in-terface based neurophysiologic tests. The future scope of this study is to build a low cost EEG device for various clinical and pre-clinical applications with specific emphasis to measure the effect of cognitive action on human brain.

  13. Pain in trigeminal neuralgia: neurophysiology and measurement: a comprehensive review.

    Science.gov (United States)

    Kumar, S; Rastogi, S; Kumar, S; Mahendra, P; Bansal, M; Chandra, L

    2013-01-01

    Trigeminal neuralgia (TN) is defined as sudden, usually unilateral, severe, brief, stabbing recurrent episodes of pain within the distribution of one or more branches of the trigeminal nerve. It is the most frequent cranial neuralgia, the incidence being 1 per 1,000,00 persons per year. Pain attacks start abruptly and last several seconds but may persist 1 to 2 minutes. The attacks are initiated by non painful physical stimulation of specific areas (trigger points or zones) that are located ipsilateral to the pain. After each episode, there is usually a refractive period during which stimulation of the trigger zone will not induce the pain. According to the European Federation of Neurological Societies (EFNS) guidelines on neuropathic pain assessment and the American Academy of Neurology (AAN)-EFNS guidelines on TN management the neurophysiological recording of trigeminal reflexes represents the most useful and reliable test for the neurophysiological diagnosis of trigeminal pains. The present article discusses different techniques for investigation of the trigeminal system by which an accurate topographical diagnosis and profile of sensory fiber pathology can be determined. With the aid of neurophysiological recordings and quantitative sensory testing, it is possible to approach a mechanism-based classification of orofacial pain.

  14. How to Program a Domain Independent Tracer for Explanations

    Science.gov (United States)

    Ishizaka, Alessio; Lusti, Markus

    2006-01-01

    Explanations are essential in the teaching process. Tracers are one possibility to provide students with explanations in an intelligent tutoring system. Their development can be divided into four steps: (a) the definition of the trace model; (b) the extraction of the information from this model; (c) the analysis and abstraction of the extracted…

  15. Self-Explanation and Explanatory Feedback in Games: Individual Differences, Gameplay, and Learning

    OpenAIRE

    Killingsworth, Stephen; Clark, Douglas; Adams, Deanne

    2015-01-01

    Previous research has demonstrated the efficacy of two explanation-based approaches for increasing learning in educational games. The first involves asking students to explain their answers (self-explanation) and the second involves providing correct explanations (explanatory feedback). This study (1) compared self-explanation and explanatory feedback features embedded into a game designed to teach Newtonian dynamics and (2) investigated relationships between learning and individual differenc...

  16. Neuroanatomy, neurophysiology, and dysfunction of the female lower urinary tract: a review.

    Science.gov (United States)

    Unger, Cécile A; Tunitsky-Bitton, Elena; Muffly, Tyler; Barber, Matthew D

    2014-01-01

    The 2 major functions of the lower urinary tract are the storage and emptying of urine. These processes are controlled by complex neurophysiologic mechanisms and are subject to injury and disease. When there is disruption of the neurologic control centers, dysfunction of the lower urinary tract may occur. This is sometimes referred to as the "neurogenic bladder." The manifestation of dysfunction depends on the level of injury and severity of disruption. Patients with lesions above the spinal cord often have detrusor overactivity with no disruption in detrusor-sphincter coordination. Patients with well-defined suprasacral spinal cord injuries usually present with intact reflex detrusor activity but have detrusor sphincter dyssynergia, whereas injuries to or below the sacral spinal cord usually lead to persistent detrusor areflexia. A complete gynecologic, urologic, and neurologic examination should be performed when evaluating patients with neurologic lower urinary tract dysfunction. In addition, urodynamic studies and neurophysiologic testing can be used in certain circumstances to help establish diagnosis or to achieve better understanding of a patient's vesicourethral functioning. In the management of neurogenic lower urinary tract dysfunction, the primary goal is improvement of a patient's quality of life. Second to this is the prevention of chronic damage to the bladder and kidneys, which can lead to worsening impairment and symptoms. Treatment is often multifactorial, including behavioral modifications, bladder training programs, and pharmacotherapy. Surgical procedures are often a last resort option for management. An understanding of the basic neurophysiologic mechanisms of the lower urinary tract can guide providers in their evaluation and treatment of patients who present with lower urinary tract disorders. As neurologic diseases progress, voiding function often changes or worsens, necessitating a good understanding of the underlying physiology in question.

  17. Tinnitus sensitization: a neurophysiological pathway of chronic complex tinnitus.

    Science.gov (United States)

    Zenner, Hans P

    2006-01-01

    A novel neuro- and psychophysiological pathway for central cognition of tinnitus, i.e. tinnitus sensitization, is presented here. As a complement to the neurophysiological pathway for the conditioned reflex according to Jastreboff, which permits therapeutic procedures to bring about an extinction of the tinnitus (e.g. by the acoustic tinnitus retraining therapy), sensitization can be treated with procedures that act at the cognitive level. Since on the one hand therapeutic extinction procedures (e.g. the therapeutic application of sound) are still to be proven effective in controlled studies, while on the other cognitive interventions such as cognitive behavioral therapies have in fact acquired evidence level IIa in prospective studies, it is indeed appropriate to discuss whether the earlier neurophysiological model of a conditioned reflex is sufficient on its own, and whether in fact it needs to be complemented with the sensitization model.

  18. Criteria for deciding what is the ’best’ scientific explanation

    NARCIS (Netherlands)

    Wagemans, J.H.M.; Mohammed, D.; Lewiński, M.

    2016-01-01

    In justifying their choice of the ‘best’ scientific explanation from a number of candidate explanations, scientists may employ specific theoretical virtues and other criteria for good scientific theories. This paper is aimed at providing an inventory of such criteria and at analyzing how they

  19. Structural Equations and Causal Explanations: Some Challenges for Causal SEM

    Science.gov (United States)

    Markus, Keith A.

    2010-01-01

    One common application of structural equation modeling (SEM) involves expressing and empirically investigating causal explanations. Nonetheless, several aspects of causal explanation that have an impact on behavioral science methodology remain poorly understood. It remains unclear whether applications of SEM should attempt to provide complete…

  20. Pupils' evaluation and generation of evidence and explanation in argumentation.

    Science.gov (United States)

    Glassner, Amnon; Weinstock, Michael; Neuman, Yair

    2005-03-01

    Studies on argument have found that participants tend to prefer explanations to evidence. This apparent bias toward explanation has been qualified recently by research that has found it to diminish with the availability of evidence. This study examines the use of explanation versus evidence in the context of argumentation with reference to the goals of particular argument situations. Seventy-nine eighth-grade pupils at a regular, urban middle school. The pupils read argumentation scenarios, each having the stated goal of either explaining or proving a claim. The pupils rated the degree to which each of two provided assertions (one a theoretical explanation, and the other evidence-based) helped achieve the goal of the argument. On a second task, the pupils chose which of the two assertions should be more effective in achieving the argument goal. On the third task, the pupils generated either an explanation or evidence for each of the argumentation scenarios. Pupils demonstrated sensitivity to the relative epistemic strength of explanation and evidence. They rated explanations as more advantageous in achieving the explanation goal, and evidence as more advantageous in achieving the proof goal. Conversely, however, when asked to generate or recall an explanation or evidence, pupils produced more explanations than evidence independent of the argumentation goal. The study refines the definition of argumentation context to include specific goals. Pupils were sensitive to the context of the argumentation situation (e.g.goals, availability of evidence). However, they appeared to have a disposition toward explanation when asked to produce an explanation or evidence-based justification.

  1. Neurophysiological localisation of ulnar neuropathy at the elbow: validation of diagnostic criteria developed by a taskforce of the Danish Society of Clinical Neurophysiology

    DEFF Research Database (Denmark)

    Pugdahl, Kirsten; Beniczky, Sándor; Wanscher, Benedikte

    2017-01-01

    OBJECTIVE: This study validates consensus criteria for localisation of ulnar neuropathy at elbow (UNE) developed by a taskforce of the Danish Society of Clinical Neurophysiology and compares them to the existing criteria from the American Association of Neuromuscular and Electrodiagnostic Medicine...

  2. Neurophysiology of Drosophila models of Parkinson's disease.

    Science.gov (United States)

    West, Ryan J H; Furmston, Rebecca; Williams, Charles A C; Elliott, Christopher J H

    2015-01-01

    We provide an insight into the role Drosophila has played in elucidating neurophysiological perturbations associated with Parkinson's disease- (PD-) related genes. Synaptic signalling deficits are observed in motor, central, and sensory systems. Given the neurological impact of disease causing mutations within these same genes in humans the phenotypes observed in fly are of significant interest. As such we observe four unique opportunities provided by fly nervous system models of Parkinson's disease. Firstly, Drosophila models are instrumental in exploring the mechanisms of neurodegeneration, with several PD-related mutations eliciting related phenotypes including sensitivity to energy supply and vesicular deformities. These are leading to the identification of plausible cellular mechanisms, which may be specific to (dopaminergic) neurons and synapses rather than general cellular phenotypes. Secondly, models show noncell autonomous signalling within the nervous system, offering the opportunity to develop our understanding of the way pathogenic signalling propagates, resembling Braak's scheme of spreading pathology in PD. Thirdly, the models link physiological deficits to changes in synaptic structure. While the structure-function relationship is complex, the genetic tractability of Drosophila offers the chance to separate fundamental changes from downstream consequences. Finally, the strong neuronal phenotypes permit relevant first in vivo drug testing.

  3. Generating explanations via analogical comparison.

    Science.gov (United States)

    Hoyos, Christian; Gentner, Dedre

    2017-10-01

    Generating explanations can be highly effective in promoting learning in both adults and children. Our interest is in the mechanisms that underlie this effect and in whether and how they operate in early learning. In adult reasoning, explanation may call on many subprocesses-including comparison, counterfactual reasoning, and reasoning by exclusion; but it is unlikely that all these processes are available to young children. We propose that one process that may serve both children and adults is comparison. In this study, we asked whether children would use the results of a comparison experience when asked to explain why a model skyscraper was stable. We focused on a challenging principle-that diagonal cross-bracing lends stability to physical structures (Gentner et al., Cognitive Science, 40, 224-240, 2016). Six-year-olds either received no training or interacted with model skyscrapers in one of three different conditions, designed to vary in their potential to invite and support comparison. In the Single Model condition, children interacted with a single braced model. In the comparison conditions (Low Alignability and High Alignability), children compared braced and unbraced models. Following experience with the models, children were asked to explain why the braced model was stable. They then received two transfer tasks. We found that children who received highly alignable pairs were most likely to (a) produce brace-based explanations and (b) transfer the brace principle to a dissimilar context. This provides evidence that children can benefit from analogical comparison in generating explanations and also suggests limitations on this ability.

  4. Neurophysiological evidence for cerebellar dysfunction in primary focal dystonia.

    NARCIS (Netherlands)

    Teo, J.T.; Warrenburg, B.P.C. van de; Schneider, S.A.; Rothwell, J.C.; Bhatia, K.P.

    2009-01-01

    Recent studies have suggested that there may be functional and structural changes in the cerebellum of patients with adult onset primary focal dystonia. The aim of this study was to establish whether there is any neurophysiological indicator of abnormal cerebellar function, using the classic

  5. [Clinical and neurophysiological aspects of severe forms of autism in children].

    Science.gov (United States)

    Simashkova, N V; Iakupova, L P; Bashina, V M

    2006-01-01

    The aim of the study was to elucidate fundamentals for the phenomenon of universality of childhood autism by comparison of clinical and neurophysiological features of its severest forms--children endogenous autism (CEA) and Rett's syndrome (RS). Each group included 20 patients. Both groups were similar by age-at-disease-onset, clinical appearances during the disease course and dynamics of psychopathological syndromes. The theta-rhythm is common for CEA and RS at the disease stage with marked signs of disease acuity, autism, regress and, therefore, may be regarded as a marker of severity and development delay. The universality of autism phenomenon in its severe forms was confirmed both at the clinical and neurophysiological levels.

  6. Relationships between the integrity and function of lumbar nerve roots as assessed by diffusion tensor imaging and neurophysiology

    Energy Technology Data Exchange (ETDEWEB)

    Chiou, S.Y.; Strutton, P.H. [Imperial College London, The Nick Davey Laboratory, Division of Surgery, Human Performance Group, Department of Surgery and Cancer, Faculty of Medicine, London (United Kingdom); Hellyer, P.J. [Imperial College London, Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, London (United Kingdom); Imperial College London, Department of Bioengineering, London (United Kingdom); Sharp, D.J. [Imperial College London, Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, London (United Kingdom); Newbould, R.D. [Imanova, Ltd, London (United Kingdom); Patel, M.C. [Charing Cross Hospital, Imaging Department, Imperial College Healthcare NHS Trust, London (United Kingdom)

    2017-09-15

    Diffusion tensor imaging (DTI) has shown promise in the measurement of peripheral nerve integrity, although the optimal way to apply the technique for the study of lumbar spinal nerves is unclear. The aims of this study are to use an improved DTI acquisition to investigate lumbar nerve root integrity and correlate this with functional measures using neurophysiology. Twenty healthy volunteers underwent 3 T DTI of the L5/S1 area. Regions of interest were applied to L5 and S1 nerve roots, and DTI metrics (fractional anisotropy, mean, axial and radial diffusivity) were derived. Neurophysiological measures were obtained from muscles innervated by L5/S1 nerves; these included the slope of motor-evoked potential input-output curves, F-wave latency, maximal motor response, and central and peripheral motor conduction times. DTI metrics were similar between the left and right sides and between vertebral levels. Conversely, significant differences in DTI measures were seen along the course of the nerves. Regression analyses revealed that DTI metrics of the L5 nerve correlated with neurophysiological measures from the muscle innervated by it. The current findings suggest that DTI has the potential to be used for assessing lumbar spinal nerve integrity and that parameters derived from DTI provide quantitative information which reflects their function. (orig.)

  7. Neurophysiological aspects of the trigeminal sensory system: an update.

    Science.gov (United States)

    Van der Cruyssen, Frederic; Politis, Constantinus

    2018-02-23

    The trigeminal system is one of the most complex cranial nerve systems of the human body. Research on it has vastly grown in recent years and concentrated more and more on molecular mechanisms and pathophysiology, but thorough reviews on this topic are lacking, certainly on the normal physiology of the trigeminal sensory system. Here we review the current literature on neurophysiology of the trigeminal nerve from peripheral receptors up to its central projections toward the somatosensory cortex. We focus on the most recent scientific discoveries and describe historical relevant research to substantiate further. One chapter on new insights of the pathophysiology of pain at the level of the trigeminal system is added. A database search of Medline, Embase and Cochrane was conducted with the search terms 'animal study', 'neurophysiology', 'trigeminal', 'oral' and 'sensory'. Articles were manually selected after reading the abstract and where needed the article. Reference lists also served to include relevant research articles. Fifty-six articles were included after critical appraisal. Physiological aspects on mechanoreceptors, trigeminal afferents, trigeminal ganglion and central projections are reviewed in light of reference works. Embryologic and anatomic insights are cited where needed. A brief description of pathophysiology of pain pathways in the trigeminal area and recent advances in dental stem cell research are also discussed. Neurophysiology at the level of the central nervous system is not reviewed. The current body of knowledge is mainly based on animal and cadaveric studies, but recent advancements in functional imaging and molecular neuroscience are elucidating the pathways and functioning of this mixed nerve system. Extrapolation of animal studies or functioning of peripheral nerves should be warranted.

  8. Simple explanations and reasoning: From philosophy of science to expert systems

    Science.gov (United States)

    Rochowiak, Daniel

    1988-01-01

    A preliminary prototype of a simple explanation system was constructed. Although the system, based on the idea of storytelling, did not incorporate all of the principles of simple explanation, it did demonstrate the potential of the approach. The system incorporated a hypertext system, an inference engine, and facilities for constructing contrast type explanations. The continued development of such a system should prove to be valuable. By extending the resources of the expert system paradigm, the knowledge engineer is not forced to learn a new set of skills, and the domain knowledge already acquired by him is not lost. Further, both the beginning user and the more advanced user can be accommodated. For the beginning user, corrective explanations and ES explanations provide facilities for more clearly understanding the way in which the system is functioning. For the more advanced user, the instance and state explanations allow him to focus on the issues at hand. The simple model of explanation attempts to exploit and show how the why and how facilities of the expert system paradigm can be extended by attending to the pragmatics of explanation and adding texture to the ordinary pattern of reasoning in a rule based system.

  9. Influence of actual and virtual chess on neurophysiology and cognition

    African Journals Online (AJOL)

    ... activity, as required in the cognitive activity of planning and processing the consequences and sequels of alternative chess moves. Integrative findings have valuable implications for future neurophysiologic, neuropsychological and cognitive psychological assessment and training of players, clinicians and researchers.

  10. Enhancing human understanding through intelligent explanations

    NARCIS (Netherlands)

    Mioch, T.; Harbers, M.; Doesburg, W.A. van; Bosch, K. van den

    2007-01-01

    Ambient systems that explain their actions promote the user's understanding as they give the user more insight in the e®ects of their behavior on the environment. In order to provide individualized intelligent explanations, we need not only to evaluate a user's observable behavior, but we also need

  11. Introductory editorial to ?Orgasm: Neurophysiological, Psychological, and Evolutionary Perspectives?

    OpenAIRE

    Klimaj, Victoria; Safron, Adam

    2016-01-01

    No abstract available.(Published: 25 October 2016)Citation: Socioaffective Neuroscience & Psychology 2016, 6: 33598 - http://dx.doi.org/10.3402/snp.v6.33598This paper is part of the Special Issue: Orgasm: Neurophysiological, Psychological, and Evolutionary Perspectives. More papers from this issue can be found at www.socioaffectiveneuroscipsychol.net

  12. Exploring the potential of neurophysiological measures for user-adaptive visualization

    NARCIS (Netherlands)

    Tak, S.; Brouwer, A.M.; Toet, A.; Erp, J.B.F. van

    2013-01-01

    User-adaptive visualization aims to adapt visualized information to the needs and characteristics of the individual user. Current approaches deploy user personality factors, user behavior and preferences, and visual scanning behavior to achieve this goal. We argue that neurophysiological data

  13. Auditory Verbal Hallucinations in Schizophrenia From a Levels of Explanation Perspective.

    Science.gov (United States)

    Hugdahl, Kenneth; Sommer, Iris E

    2018-02-15

    In the present article, we present a "Levels of Explanation" (LoE) approach to auditory verbal hallucinations (AVHs) in schizophrenia. Mental phenomena can be understood at different levels of explanation, including cultural, clinical, cognitive, brain imaging, cellular, and molecular levels. Current research on AVHs is characterized by accumulation of data at all levels, but with little or no interaction of findings between levels. A second advantage with a Levels of Explanation approach is that it fosters interdisciplinarity and collaboration across traditional borders, facilitating a real breakthrough in future research. We exemplify a Levels of Explanation approach with data from 3 levels where findings at 1 level provide predictions for another level. More specifically, we show how functional neuroimaging data at the brain level correspond with behavioral data at the cognitive level, and how data at these 2 levels correspond with recent findings of changes in neurotransmitter function at the cellular level. We further discuss implications for new therapeutic interventions, and the article is ended by suggestion how future research could incorporate genetic influences on AVHs at the molecular level of explanation by providing examples for animal work.

  14. Neuropathy in the hemodialysis population: a review of neurophysiology referrals in a tertiary center.

    LENUS (Irish Health Repository)

    O'Regan, John

    2012-01-01

    This was a retrospective observational study of neurophysiology referrals over 8 years from a tertiary referral center in Ireland. A total of 68 of the 73 referrals yielded one or more abnormalities. Thirty-nine (53%) patients had one or more mononeuropathies; iatrogenic mononeuropathies believed to be associated with arterio-venous fistula creation occurred in 15 patients. Polyneuropathy was identified in 43 patients (59%). Access to an experienced neurophysiology department offers valuable insight into dialysis-associated neuropathies, especially when associated with arterio-venous fistulae.

  15. Model-based explanation of plant knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Huuskonen, P.J. [VTT Electronics, Oulu (Finland). Embedded Software

    1997-12-31

    This thesis deals with computer explanation of knowledge related to design and operation of industrial plants. The needs for explanation are motivated through case studies and literature reviews. A general framework for analysing plant explanations is presented. Prototypes demonstrate key mechanisms for implementing parts of the framework. Power plants, steel mills, paper factories, and high energy physics control systems are studied to set requirements for explanation. The main problems are seen to be either lack or abundance of information. Design knowledge in particular is found missing at plants. Support systems and automation should be enhanced with ways to explain plant knowledge to the plant staff. A framework is formulated for analysing explanations of plant knowledge. It consists of three parts: 1. a typology of explanation, organised by the class of knowledge (factual, functional, or strategic) and by the target of explanation (processes, automation, or support systems), 2. an identification of explanation tasks generic for the plant domain, and 3. an identification of essential model types for explanation (structural, behavioural, functional, and teleological). The tasks use the models to create the explanations of the given classes. Key mechanisms are discussed to implement the generic explanation tasks. Knowledge representations based on objects and their relations form a vocabulary to model and present plant knowledge. A particular class of models, means-end models, are used to explain plant knowledge. Explanations are generated through searches in the models. Hypertext is adopted to communicate explanations over dialogue based on context. The results are demonstrated in prototypes. The VICE prototype explains the reasoning of an expert system for diagnosis of rotating machines at power plants. The Justifier prototype explains design knowledge obtained from an object-oriented plant design tool. Enhanced access mechanisms into on-line documentation are

  16. Model-based explanation of plant knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Huuskonen, P J [VTT Electronics, Oulu (Finland). Embedded Software

    1998-12-31

    This thesis deals with computer explanation of knowledge related to design and operation of industrial plants. The needs for explanation are motivated through case studies and literature reviews. A general framework for analysing plant explanations is presented. Prototypes demonstrate key mechanisms for implementing parts of the framework. Power plants, steel mills, paper factories, and high energy physics control systems are studied to set requirements for explanation. The main problems are seen to be either lack or abundance of information. Design knowledge in particular is found missing at plants. Support systems and automation should be enhanced with ways to explain plant knowledge to the plant staff. A framework is formulated for analysing explanations of plant knowledge. It consists of three parts: 1. a typology of explanation, organised by the class of knowledge (factual, functional, or strategic) and by the target of explanation (processes, automation, or support systems), 2. an identification of explanation tasks generic for the plant domain, and 3. an identification of essential model types for explanation (structural, behavioural, functional, and teleological). The tasks use the models to create the explanations of the given classes. Key mechanisms are discussed to implement the generic explanation tasks. Knowledge representations based on objects and their relations form a vocabulary to model and present plant knowledge. A particular class of models, means-end models, are used to explain plant knowledge. Explanations are generated through searches in the models. Hypertext is adopted to communicate explanations over dialogue based on context. The results are demonstrated in prototypes. The VICE prototype explains the reasoning of an expert system for diagnosis of rotating machines at power plants. The Justifier prototype explains design knowledge obtained from an object-oriented plant design tool. Enhanced access mechanisms into on-line documentation are

  17. Explanation components as interactive tools

    Energy Technology Data Exchange (ETDEWEB)

    Wahlster, W.

    1983-01-01

    The ability to explain itself is probably the most important criterion of the user-friendliness of interactive systems. Explanation aids in the form of simple help functions do not meet this criterion. The reasons for this are outlined. More promising is an explanation component which can give the user intelligible and context-oriented explanations. The essential requirement for this is the development of knowledge-based interactive systems using artificial intelligence methods and techniques. The authors report on experiences with the development of explanation components, in particular a number of examples from the HAM-ANS project. 12 references.

  18. Neurophysiological findings relevant to echolocation in marine animals

    Science.gov (United States)

    Bullock, T. H.; Ridgway, S. H.

    1972-01-01

    A review of echolocation mechanisms in marine mammals, chiefly porpoises, is given. Data cover peripheral auditory and central neurophysiological specializations favorable to the analysis of echolocating clicks and their echoes. Conclusions show (1) signals are received from 50 up to at least 135 kHz, (2) sound is received through the mandible skin, and (3) the midbrain sites are insensitive to low frequencies (below 6 kHz).

  19. Resting-State Neurophysiological Activity Patterns in Young People with ASD, ADHD, and ASD + ADHD.

    Science.gov (United States)

    Shephard, Elizabeth; Tye, Charlotte; Ashwood, Karen L; Azadi, Bahar; Asherson, Philip; Bolton, Patrick F; McLoughlin, Grainne

    2018-01-01

    Altered power of resting-state neurophysiological activity has been associated with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), which commonly co-occur. We compared resting-state neurophysiological power in children with ASD, ADHD, co-occurring ASD + ADHD, and typically developing controls. Children with ASD (ASD/ASD + ADHD) showed reduced theta and alpha power compared to children without ASD (controls/ADHD). Children with ADHD (ADHD/ASD + ADHD) displayed decreased delta power compared to children without ADHD (ASD/controls). Children with ASD + ADHD largely presented as an additive co-occurrence with deficits of both disorders, although reduced theta compared to ADHD-only and reduced delta compared to controls suggested some unique markers. Identifying specific neurophysiological profiles in ASD and ADHD may assist in characterising more homogeneous subgroups to inform treatment approaches and aetiological investigations.

  20. Behavioural and neurophysiological evidence for face identity and face emotion processing in animals

    Science.gov (United States)

    Tate, Andrew J; Fischer, Hanno; Leigh, Andrea E; Kendrick, Keith M

    2006-01-01

    Visual cues from faces provide important social information relating to individual identity, sexual attraction and emotional state. Behavioural and neurophysiological studies on both monkeys and sheep have shown that specialized skills and neural systems for processing these complex cues to guide behaviour have evolved in a number of mammals and are not present exclusively in humans. Indeed, there are remarkable similarities in the ways that faces are processed by the brain in humans and other mammalian species. While human studies with brain imaging and gross neurophysiological recording approaches have revealed global aspects of the face-processing network, they cannot investigate how information is encoded by specific neural networks. Single neuron electrophysiological recording approaches in both monkeys and sheep have, however, provided some insights into the neural encoding principles involved and, particularly, the presence of a remarkable degree of high-level encoding even at the level of a specific face. Recent developments that allow simultaneous recordings to be made from many hundreds of individual neurons are also beginning to reveal evidence for global aspects of a population-based code. This review will summarize what we have learned so far from these animal-based studies about the way the mammalian brain processes the faces and the emotions they can communicate, as well as associated capacities such as how identity and emotion cues are dissociated and how face imagery might be generated. It will also try to highlight what questions and advances in knowledge still challenge us in order to provide a complete understanding of just how brain networks perform this complex and important social recognition task. PMID:17118930

  1. Sexual dysfunction following surgery for rectal cancer - a clinical and neurophysiological study

    Directory of Open Access Journals (Sweden)

    Sperduti Isabella

    2009-09-01

    Full Text Available Abstract Background Sexual dysfunction following surgery for rectal cancer may be frequent and often severe. The aim of the present study is to evaluate the occurrence of this complication from both a clinical point of view and by means of neurophysiological tests. Methods We studied a group of 57 patients submitted to rectal resection for adenocarcinoma. All the patients underwent neurological, psychological and the following neurophysiological tests: sacral reflex (SR, pudendal somatosensory evoked potentials (PEPs, motor evoked potential (MEPs and sympathetic skin responses (SSRs. The results were compared with a control group of 67 rectal cancer patients studied before surgery. Only 10 of these patients could be studied both pre- and postoperatively. 10 patients submitted to high dose preoperative chemoradiation were studied to evaluate the effect of this treatment on sexual function. Statistical analysis was performed by means of the two-tailed Student's t test for paired observations and k concordance test. Results 59.6% of patients operated reported sexual dysfunction, while this symptom occurred in 16.4% in the control group. Moreover, a significantly higher rate of alterations of the neurophysiological tests and longer mean latencies of the SR, PEPs, MEPs and SSRs were observed in the patients who had undergone resection. In the 10 patients studied both pre and post-surgery impotence occurred in 6 of them and the mean latencies of SSRs were longer after operation. In the 10 patients studied pre and post chemoradiation impotence occurred in 1 patient only, showing the mild effect of these treatments on sexual function. Conclusion Patients operated showed severe sexual dysfunctions. The neurophysiological test may be a useful tool to investigate this complication. The neurological damage could be monitored to decide the rehabilitation strategy.

  2. Neurophysiological Correlates of Attentional Fluctuation in Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Cheung, Celeste H M; McLoughlin, Gráinne; Brandeis, Daniel; Banaschewski, Tobias; Asherson, Philip; Kuntsi, Jonna

    2017-05-01

    Cognitive performance in attention-deficit/hyperactivity disorder (ADHD) is characterised, in part, by frequent fluctuations in response speed, resulting in high reaction time variability (RTV). RTV captures a large proportion of the genetic risk in ADHD but, importantly, is malleable, improving significantly in a fast-paced, rewarded task condition. Using the temporal precision offered by event-related potentials (ERPs), we aimed to examine the neurophysiological measures of attention allocation (P3 amplitudes) and preparation (contingent negative variation, CNV), and their associations with the fluctuating RT performance and its improvement in ADHD. 93 participants with ADHD and 174 controls completed the baseline and fast-incentive conditions of a four-choice reaction time task, while EEG was simultaneously recorded. Compared to controls, individuals with ADHD showed both increased RTV and reduced P3 amplitudes during performance on the RT task. In the participants with ADHD, attenuated P3 amplitudes were significantly associated with high RTV, and the increase in P3 amplitudes from a slow baseline to a fast-paced, rewarded condition was significantly associated with the RTV decrease. Yet, the individuals with ADHD did not show the same increase in CNV from baseline to fast-incentive condition as observed in controls. ADHD is associated both with a neurophysiological impairment of attention allocation (P3 amplitudes) and an inability to adjust the preparatory state (CNV) in a changed context. Our findings suggest that both neurophysiological and cognitive performance measures of attention are malleable in ADHD, which are potential targets for non-pharmacological interventions.

  3. Backwards and Forwards: Behavioral and Neurophysiological Investigations into Dependency Processing

    Science.gov (United States)

    Witzel, Jeffrey D.

    2010-01-01

    This dissertation examines the processing of sentences involving long-distance linguistic dependencies, or sentences containing elements that must be linked across intervening words and phrases. Specifically, both behavioral (self-paced reading and eye tracking) and neurophysiological (electroencephalography) methods were used (a) to evaluate the…

  4. Cannabinoids and Vanilloids in Schizophrenia: Neurophysiological Evidence and Directions for Basic Research

    Directory of Open Access Journals (Sweden)

    Rafael N. Ruggiero

    2017-06-01

    Full Text Available Much of our knowledge of the endocannabinoid system in schizophrenia comes from behavioral measures in rodents, like prepulse inhibition of the acoustic startle and open-field locomotion, which are commonly used along with neurochemical approaches or drug challenge designs. Such methods continue to map fundamental mechanisms of sensorimotor gating, hyperlocomotion, social interaction, and underlying monoaminergic, glutamatergic, and GABAergic disturbances. These strategies will require, however, a greater use of neurophysiological tools to better inform clinical research. In this sense, electrophysiology and viral vector-based circuit dissection, like optogenetics, can further elucidate how exogenous cannabinoids worsen (e.g., tetrahydrocannabinol, THC or ameliorate (e.g., cannabidiol, CBD schizophrenia symptoms, like hallucinations, delusions, and cognitive deficits. Also, recent studies point to a complex endocannabinoid-endovanilloid interplay, including the influence of anandamide (endogenous CB1 and TRPV1 agonist on cognitive variables, such as aversive memory extinction. In fact, growing interest has been devoted to TRPV1 receptors as promising therapeutic targets. Here, these issues are reviewed with an emphasis on the neurophysiological evidence. First, we contextualize imaging and electrographic findings in humans. Then, we present a comprehensive review on rodent electrophysiology. Finally, we discuss how basic research will benefit from further combining psychopharmacological and neurophysiological tools.

  5. Music evolution in the laboratory: Cultural transmission meets neurophysiology

    DEFF Research Database (Denmark)

    Lumaca, Massimo; Ravignani, Andrea; Baggio, G.

    2018-01-01

    In recent years, there has been a renewed interest in the biological and cultural origins of music, and specifically in the role played by perceptual and cognitive biases and constraints in shaping core features of musical systems, such as melody, harmony, and rhythm. One proposal originates...... of music transmission. In this paper, we first review some of the most important theoretical and empirical contributions to this area of research. Next, we identify one major current limitation of these studies: the lack of direct neural support for the hypothesis of cognitive adaptation. Finally, we...... discuss a recent experiment in which this issue was addressed using event-related brain potentials (ERPs). We argue that the introduction of neurophysiology in cultural transmission research may provide new insights on the micro-evolutionary origins of forms of variation observed in cultural systems....

  6. Society by Numbers : Studies on Model-Based Explanations in the Social Sciences

    OpenAIRE

    Kuorikoski, Jaakko

    2010-01-01

    The aim of this dissertation is to provide conceptual tools for the social scientist for clarifying, evaluating and comparing explanations of social phenomena based on formal mathematical models. The focus is on relatively simple theoretical models and simulations, not statistical models. These studies apply a theory of explanation according to which explanation is about tracing objective relations of dependence, knowledge of which enables answers to contrastive why and how-questions. This th...

  7. Clinical and neurophysiological investigation of a large family with dominant Charcot-Marie-Tooth type 2 disease with pyramidal signs

    Directory of Open Access Journals (Sweden)

    Eduardo Luis de Aquino Neves

    2011-06-01

    Full Text Available Charcot-Marie-Tooth (CMT disease is a hereditary neuropathy of motor and sensory impairment with distal predominance. Atrophy and weakness of lower limbs are the first signs of the disease. It can be classified, with the aid of electromyography and nerve conduction studies, as demyelinating (CMT1 or axonal (CMT2. OBJECTIVE: Clinical and neurophysiological investigation of a large multigenerational family with CMT2 with autosomal dominant mode of transmission. METHOD: Fifty individuals were evaluated and neurophysiological studies performed in 22 patients. RESULTS: Thirty individuals had clinical signs of motor-sensory neuropathy. Babinski sign was present in 14 individuals. Neurophysiological study showed motor-sensory axonal polyneuropathy. CONCLUSION: The clinical and neurophysiological characteristics of this family does not differ from those observed with other forms of CMT, except for the high prevalence of Babinski sign.

  8. Clinical neurophysiology and quantitative sensory testing in the investigation of orofacial pain and sensory function.

    Science.gov (United States)

    Jääskeläinen, Satu K

    2004-01-01

    Chronic orofacial pain represents a diagnostic and treatment challenge for the clinician. Some conditions, such as atypical facial pain, still lack proper diagnostic criteria, and their etiology is not known. The recent development of neurophysiological methods and quantitative sensory testing for the examination of the trigeminal somatosensory system offers several tools for diagnostic and etiological investigation of orofacial pain. This review presents some of these techniques and the results of their application in studies on orofacial pain and sensory dysfunction. Clinical neurophysiological investigation has greater diagnostic accuracy and sensitivity than clinical examination in the detection of the neurogenic abnormalities of either peripheral or central origin that may underlie symptoms of orofacial pain and sensory dysfunction. Neurophysiological testing may also reveal trigeminal pathology when magnetic resonance imaging has failed to detect it, so these methods should be considered complementary to each other in the investigation of orofacial pain patients. The blink reflex, corneal reflex, jaw jerk, sensory neurography of the inferior alveolar nerve, and the recording of trigeminal somatosensory-evoked potentials with near-nerve stimulation have all proved to be sensitive and reliable in the detection of dysfunction of the myelinated sensory fibers of the trigeminal nerve or its central connections within the brainstem. With appropriately small thermodes, thermal quantitative sensory testing is useful for the detection of trigeminal small-fiber dysfunction (Adelta and C). In neuropathic conditions, it is most sensitive to lesions causing axonal injury. By combining different techniques for investigation of the trigeminal system, an accurate topographical diagnosis and profile of sensory fiber pathology can be determined. Neurophysiological and quantitative sensory tests have already highlighted some similarities among various orofacial pain conditions

  9. Neurophysiological characterization of postherniotomy pain

    DEFF Research Database (Denmark)

    Aasvang, Eske Kvanner; Brandsborg, Birgitte; Christensen, Bente

    2008-01-01

    Inguinal herniotomy is one of the most frequent surgical procedures and chronic pain affecting everyday activities is reported in approximately 10% of patients. However, the neurophysiological changes and underlying pathophysiological mechanisms of postherniotomy pain are not known in detail...... postoperatively. A quantitative sensory testing protocol was used, assessing sensory dysfunction type, location and severity. We assessed the protocol test-retest variability using data from healthy control subjects. All patients (pain and pain-free) had signs of nerve damage, seen as sensory dysfunction......). The specific finding of reduced pain detection threshold over the external inguinal annulus is consistent with damage to the cutaneous innervation territory of nervous structures in the inguinal region. The correspondence between pain location and sensory disturbance suggests that the pain is neuropathic...

  10. On the nature of explanation: A PDP approach

    Science.gov (United States)

    Churchland, Paul M.

    1990-06-01

    Neural network models of sensory processing and associative memory provide the resources for a new theory of what explanatory understanding consists in. That theory finds the theoretically important factors to reside not at the level of propositions and the relations between them, but at the level of the activation patterns across large populations of neurons. The theory portrays explanatory understanding, perceptual recognition, and abductive inference as being different instances of the same more general sort of cognitive achievement, viz. prototype activation. It thus effects a unification of the theories of explanation, perception, and ampliative inference. It also finds systematic unity in the wide diversity of types of explanation (causal, functional, mathematical, intentional, reductive, etc.), a chronic problem for theories of explanation in the logico-linguistic tradition. Finally, it is free of the many defects, both logical and psychological, that plague models in that older tradition.

  11. Multimodal neurophysiological and psychometric evaluation among patients with systemic lupus erythematosus

    Science.gov (United States)

    Shehata, Ghaydaa A; Elserogy, Yasser MB; Ahmad, Hossam Eddin K; Abdel-Kareem, Mohamed I; Al-kabeer, Ashraf M; Rayan, Mohamed M; El-Baky, Mohamed ES Abd

    2011-01-01

    Objective: To determine some of the neuropsychiatric manifestations of systemic lupus erythematosus (SLE) by applying multimodal neurophysiological and psychometric studies. Patients and methods: Twenty-six SLE patients were evaluated for neurological and psychiatric disorders and compared with 26 healthy controls matched for age, sex, education, and social class. The severity of SLE disease was assessed. Each subject was subjected to the following examinations: laboratory, neurophysiology, magnetic resonance imaging of the brain, transcranial duplex, Modified Mini-mental State Examination, Cognitive Assessment Scale Inventory, Hamilton Depression Scale, and Hamilton Anxiety Scale. Results: The mean age of subjects was 25.9 ± 8.9 years. The most prevalent neurological manifestations were (in order of frequency) anxiety in 17 cases (65.4%), depression in 15 cases (57.7%), headache in 10 cases (38.5%), peripheral neuropathy in 7 cases (26.9%), seizures in 6 cases (23.1%), psychosis in 5 cases (19.2%), dementia in 4 cases (15.4%), radiculopathy in 4 cases (15.4%), myositis in 3 cases (11.5%), and stroke in 2 cases (7.7%). There was a significant affection in amplitude of the ulnar nerve, cognitive function impairment, and electroencephalography changes. There was a significant increased mean velocity and decreased Pulsatility Index of the most studied intracranial vessels in the patients. Conclusion: The use of multimodal neurophysiological, transcranial duplex, and psychometric scales increases the sensitivity for detecting nervous system involvement. PMID:21674025

  12. Why the Difference Between Explanation and Argument Matters to Science Education

    Science.gov (United States)

    Brigandt, Ingo

    2016-05-01

    Contributing to the recent debate on whether or not explanations ought to be differentiated from arguments, this article argues that the distinction matters to science education. I articulate the distinction in terms of explanations and arguments having to meet different standards of adequacy. Standards of explanatory adequacy are important because they correspond to what counts as a good explanation in a science classroom, whereas a focus on evidence-based argumentation can obscure such standards of what makes an explanation explanatory. I provide further reasons for the relevance of not conflating explanations with arguments (and having standards of explanatory adequacy in view). First, what guides the adoption of the particular standards of explanatory adequacy that are relevant in a scientific case is the explanatory aim pursued in this context. Apart from explanatory aims being an important aspect of the nature of science, including explanatory aims in classroom instruction also promotes students seeing explanations as more than facts, and engages them in developing explanations as responses to interesting explanatory problems. Second, it is of relevance to science curricula that science aims at intervening in natural processes, not only for technological applications, but also as part of experimental discovery. Not any argument enables intervention in nature, as successful intervention specifically presupposes causal explanations. Students can fruitfully explore in the classroom how an explanatory account suggests different options for intervention.

  13. A neurophysiological study of facial numbness in multiple sclerosis: Integration with clinical data and imaging findings.

    Science.gov (United States)

    Koutsis, Georgios; Kokotis, Panagiotis; Papagianni, Aikaterini E; Evangelopoulos, Maria-Eleftheria; Kilidireas, Constantinos; Karandreas, Nikolaos

    2016-09-01

    To integrate neurophysiological findings with clinical and imaging data in a consecutive series of multiple sclerosis (MS) patients developing facial numbness during the course of an MS attack. Nine consecutive patients with MS and recent-onset facial numbness were studied clinically, imaged with routine MRI, and assessed neurophysiologically with trigeminal somatosensory evoked potential (TSEP), blink reflex (BR), masseter reflex (MR), facial nerve conduction, facial muscle and masseter EMG studies. All patients had unilateral facial hypoesthesia on examination and lesions in the ipsilateral pontine tegmentum on MRI. All patients had abnormal TSEPs upon stimulation of the affected side, excepting one that was tested following remission of numbness. BR was the second most sensitive neurophysiological method with 6/9 examinations exhibiting an abnormal R1 component. The MR was abnormal in 3/6 patients, always on the affected side. Facial conduction and EMG studies were normal in all patients but one. Facial numbness was always related to abnormal TSEPs. A concomitant R1 abnormality on BR allowed localization of the responsible pontine lesion, which closely corresponded with MRI findings. We conclude that neurophysiological assessment of MS patients with facial numbness is a sensitive tool, which complements MRI, and can improve lesion localization. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Punishment induced behavioural and neurophysiological variability reveals dopamine-dependent selection of kinematic movement parameters

    Science.gov (United States)

    Galea, Joseph M.; Ruge, Diane; Buijink, Arthur; Bestmann, Sven; Rothwell, John C.

    2013-01-01

    Action selection describes the high-level process which selects between competing movements. In animals, behavioural variability is critical for the motor exploration required to select the action which optimizes reward and minimizes cost/punishment, and is guided by dopamine (DA). The aim of this study was to test in humans whether low-level movement parameters are affected by punishment and reward in ways similar to high-level action selection. Moreover, we addressed the proposed dependence of behavioural and neurophysiological variability on DA, and whether this may underpin the exploration of kinematic parameters. Participants performed an out-and-back index finger movement and were instructed that monetary reward and punishment were based on its maximal acceleration (MA). In fact, the feedback was not contingent on the participant’s behaviour but pre-determined. Blocks highly-biased towards punishment were associated with increased MA variability relative to blocks with either reward or without feedback. This increase in behavioural variability was positively correlated with neurophysiological variability, as measured by changes in cortico-spinal excitability with transcranial magnetic stimulation over the primary motor cortex. Following the administration of a DA-antagonist, the variability associated with punishment diminished and the correlation between behavioural and neurophysiological variability no longer existed. Similar changes in variability were not observed when participants executed a pre-determined MA, nor did DA influence resting neurophysiological variability. Thus, under conditions of punishment, DA-dependent processes influence the selection of low-level movement parameters. We propose that the enhanced behavioural variability reflects the exploration of kinematic parameters for less punishing, or conversely more rewarding, outcomes. PMID:23447607

  15. New wine in an old bottle: does alienation provide an explanation of the origins of physician discontent?

    Science.gov (United States)

    McKinlay, John B; Marceau, Lisa

    2011-01-01

    We have witnessed transformational changes to the U.S. health care system over several decades. Alongside these changes is an increasing number of research reports and commentaries on physician workplace dissatisfaction and discontent. Primary care physicians, in particular, report dissatisfaction with conditions on the ground. Is there solid evidence concerning the magnitude of doctors' discontent, and how is it changing over time? Is it confined to the United States, or is it also occurring in other countries with different health care systems? Does physician discontent affect the processes, quality, and outcomes of medical care? This article addresses these questions. It considers the dimensions of physician dissatisfaction, whether there is a problem, and competing contributions to physician discontent. The authors suggest that the classic concept of alienation may build upon valuable earlier work and provide a new, coherent explanation of the workplace origins of physician discontent. Alienation theory combines both structural and psychological components associated with workplace discontent and has the potential to explain the changing position of knowledge workers (such as physicians) in the new economy.

  16. Leg Regrowth in Blaberus discoidalis (Discoid Cockroach) following Limb Autotomy versus Limb Severance and Relevance to Neurophysiology Experiments

    Science.gov (United States)

    Marzullo, Timothy C.

    2016-01-01

    Background Many insects can regenerate limbs, but less is known about the regrowth process with regard to limb injury type. As part of our neurophysiology education experiments involving the removal of a cockroach leg, 1) the ability of Blaberus discoidalis cockroaches to regenerate a metathoracic leg was examined following autotomy at the femur/trochanter joint versus severance via a transverse coxa-cut, and 2) the neurophysiology of the detached legs with regard to leg removal type was studied by measuring spike firing rate and microstimulation movement thresholds. Leg Regrowth Results First appearance of leg regrowth was after 5 weeks in the autotomy group and 12 weeks in the coxa-cut group. Moreover, regenerated legs in the autotomy group were 72% of full size on first appearance, significantly larger (pbarbs, and a 10% higher electrical microstimulation threshold for movement. Summary It is recommended that neurophysiology experiments on cockroach legs remove the limb at autotomy joints instead of coxa cuts, as the leg regenerates significantly faster when autotomized and does not detract from the neurophysiology educational content. PMID:26824931

  17. Auditory-neurophysiological responses to speech during early childhood: Effects of background noise.

    Science.gov (United States)

    White-Schwoch, Travis; Davies, Evan C; Thompson, Elaine C; Woodruff Carr, Kali; Nicol, Trent; Bradlow, Ann R; Kraus, Nina

    2015-10-01

    Early childhood is a critical period of auditory learning, during which children are constantly mapping sounds to meaning. But this auditory learning rarely occurs in ideal listening conditions-children are forced to listen against a relentless din. This background noise degrades the neural coding of these critical sounds, in turn interfering with auditory learning. Despite the importance of robust and reliable auditory processing during early childhood, little is known about the neurophysiology underlying speech processing in children so young. To better understand the physiological constraints these adverse listening scenarios impose on speech sound coding during early childhood, auditory-neurophysiological responses were elicited to a consonant-vowel syllable in quiet and background noise in a cohort of typically-developing preschoolers (ages 3-5 yr). Overall, responses were degraded in noise: they were smaller, less stable across trials, slower, and there was poorer coding of spectral content and the temporal envelope. These effects were exacerbated in response to the consonant transition relative to the vowel, suggesting that the neural coding of spectrotemporally-dynamic speech features is more tenuous in noise than the coding of static features-even in children this young. Neural coding of speech temporal fine structure, however, was more resilient to the addition of background noise than coding of temporal envelope information. Taken together, these results demonstrate that noise places a neurophysiological constraint on speech processing during early childhood by causing a breakdown in neural processing of speech acoustics. These results may explain why some listeners have inordinate difficulties understanding speech in noise. Speech-elicited auditory-neurophysiological responses offer objective insight into listening skills during early childhood by reflecting the integrity of neural coding in quiet and noise; this paper documents typical response

  18. Towards an Explanation Generation System for Robots: Analysis and Recommendations

    Directory of Open Access Journals (Sweden)

    Ben Meadows

    2016-10-01

    Full Text Available A fundamental challenge in robotics is to reason with incomplete domain knowledge to explain unexpected observations and partial descriptions extracted from sensor observations. Existing explanation generation systems draw on ideas that can be mapped to a multidimensional space of system characteristics, defined by distinctions, such as how they represent knowledge and if and how they reason with heuristic guidance. Instances in this multidimensional space corresponding to existing systems do not support all of the desired explanation generation capabilities for robots. We seek to address this limitation by thoroughly understanding the range of explanation generation capabilities and the interplay between the distinctions that characterize them. Towards this objective, this paper first specifies three fundamental distinctions that can be used to characterize many existing explanation generation systems. We explore and understand the effects of these distinctions by comparing the capabilities of two systems that differ substantially along these axes, using execution scenarios involving a robot waiter assisting in seating people and delivering orders in a restaurant. The second part of the paper uses this study to argue that the desired explanation generation capabilities corresponding to these three distinctions can mostly be achieved by exploiting the complementary strengths of the two systems that were explored. This is followed by a discussion of the capabilities related to other major distinctions to provide detailed recommendations for developing an explanation generation system for robots.

  19. Behavioural and neurophysiological study of olfactory perception and learning in honeybees

    Directory of Open Access Journals (Sweden)

    Jean-Christophe eSandoz

    2011-12-01

    Full Text Available The honeybee Apis mellifera has been a central insect model in the study of olfactory perception and learning for more than a century, starting with pioneer work by Karl von Frisch. Research on olfaction in honeybees has greatly benefited from the advent of a range of behavioural and neurophysiological paradigms in the Lab. Here I review major findings about how the honeybee brain detects, processes, and learns odours, based on behavioural, neuroanatomical and neurophysiological approaches. I first address the behavioural study of olfactory learning, from experiments on free-flying workers visiting artificial flowers to laboratory-based conditioning protocols on restrained individuals. I explain how the study of olfactory learning has allowed understanding the discrimination and generalization ability of the honeybee olfactory system, its capacity to grant special properties to olfactory mixtures as well as to retain individual component information. Next, based on the impressive amount of anatomical and immunochemical studies of the bee brain, I detail our knowledge of olfactory pathways. I then show how functional recordings of odour-evoked activity in the brain allow following the transformation of the olfactory message from the periphery until higher-order central structures. Data from extra- and intracellular electrophysiological approaches as well as from the most recent optical imaging developments are described. Lastly, I discuss results addressing how odour representation changes as a result of experience. This impressive ensemble of behavioural, neuroanatomical and neurophysiological data available in the bee make it an attractive model for future research aiming to understand olfactory perception and learning in an integrative fashion.

  20. Scientific explanation in school: An enactive view

    Science.gov (United States)

    Ibrahim-Didi, Khadeeja

    This study explores explanation-in-action, a corollary to an enactive orientation to cognition. Explanation, understood this way is identified as a semiotic, perceptually driven activity, where the interactions that arise between students that enable the engagement to continue indicate a certain tentative coherence of meaning that is brought forth in interaction in a constraining environment. Challenging summary state views of explanation as statement, this study explores the evolution of scientific explanation in two Grade Eight Maldivian classrooms. Enactivism, understood across different embodied cognitive systems, reconfigures the discourse on explanation by re-orienting the form in which explanation is understood. The notion of explanation-in-action as a topological function implicates the boundary of the cognitive system in the action. Further, it also recognizes that embedding boundaries and the dynamics that create the boundaries can constrain the explanation that occurs in different domains. In effect, the study calls for reconfiguring validation as in-action---as the constraining dynamic feature that emerges in the ongoing explanation-in-action. In the study I pay attention to the different boundaries of some systemic configurations in the classroom. I consider how the boundary conditions create the possibility for signification, and therefore, explanation. This research suggests that in explaining-in-action students are able to draw on the enabling possibilities of personal boundaries and the constraining social boundaries to further structure their explaining in ways that are local to the task at hand.

  1. Students' self-explanations while solving unfamiliar cases: the role of biomedical knowledge.

    Science.gov (United States)

    Chamberland, Martine; Mamede, Sílvia; St-Onge, Christina; Rivard, Marc-Antoine; Setrakian, Jean; Lévesque, Annie; Lanthier, Luc; Schmidt, Henk G; Rikers, Remy M J P

    2013-11-01

    General guidelines for teaching clinical reasoning have received much attention, despite a paucity of instructional approaches with demonstrated effectiveness. As suggested in a recent experimental study, self-explanation while solving clinical cases may be an effective strategy to foster reasoning in clinical clerks dealing with less familiar cases. However, the mechanisms that mediate this benefit have not been specifically investigated. The aim of this study was to explore the types of knowledge used by students when solving familiar and less familiar clinical cases with self-explanation. In a previous study, 36 third-year medical students diagnosed familiar and less familiar clinical cases either by engaging in self-explanation or not. Based on an analysis of previously collected data, the present study compared the content of self-explanation protocols generated by seven randomly selected students while solving four familiar and four less familiar cases. In total, 56 verbal protocols (28 familiar and 28 less familiar) were segmented and coded using the following categories: paraphrases, biomedical inferences, clinical inferences, monitoring statements and errors. Students provided more self-explanation segments from less familiar cases (M = 275.29) than from familiar cases (M = 248.71, p = 0.046). They provided significantly more paraphrases (p = 0.001) and made more errors (p = 0.008). A significant interaction was found between familiarity and the type of inferences (biomedical versus clinical, p = 0.016). When self-explaining less familiar cases, students provided significantly more biomedical inferences than familiar cases. Lack of familiarity with a case seems to stimulate medical students to engage in more extensive thinking during self-explanation. Less familiar cases seem to activate students' biomedical knowledge, which in turn helps them to create new links between biomedical and clinical knowledge, and eventually construct a more coherent mental

  2. Neurophysiological correlates of the pathway to the early stages of psychosis

    NARCIS (Netherlands)

    van Tricht, M.J.

    2013-01-01

    Our results indicate that in help-seeking individuals who meet the criteria for ‘at risk mental state’, particular neurophysiological paradigms (i.e. parietal P300 amplitudes and resting state QEEG theta and delta power and individual alpha peak frequency) can contribute to the differentiation

  3. Neurophysiology of visual aura in migraine

    International Nuclear Information System (INIS)

    Shibata, Koichi

    2007-01-01

    Visual processing in migraine has been targeted because the visual symptoms that are commonly associated with attack, either in the form of aura or other more subtle symptoms, indicate that the visual pathways are involved in migrainous pathophysiology. The visual aura of the migraine attack has been explained by the cortical spreading depression (CSD) of Leao, neuroelectric event beginning in the occipital cortex and propagating into contiguous brain region. Clinical observations suggest that hyperexcitability occurs not only during the attack, typically in the form of photophobia, but also between attacks. Numerous human neuroimaging, neurophysiological and psychophysical studies have identified differences in cortical visual processing in migraine. The possibility of imaging the typical visual aura with BOLD functional MRI has revealed multiple neurovascular events in the occipital cortex within a single attack that closely resemble CSD. As transient synchronized neuronal excitation precedes CSD, changes in cortical excitability underlie the migraine attack. Independent evidence for altered neuronal excitability in migraineurs between attacks emerges from visual evoked potentials (VEPs) and transcranial magnetic stimulation (TMS), recordings of cortical potentials and psychophysics. Recently, both TMS and psychophysical studies measuring visual performance in migraineurs have used measures which presumably measure primary visual (V1) and visual association cortex. Our VEP and blink reflex study showed that migraine patients exhibiting allodynia might show central sensitization of braistem trigeminal neuron and had contrast modulation dysfunction during the cortical visual processing of V1 and visual association cortex in-between attacks. In pathophysiology of migraine, these neurophysiological and psychophysical studies indicate that abnormal visual and trigeminal hyperexcitability might persist between migraine attacks. The influence of migraine on cortical

  4. Inside case-based explanation

    CERN Document Server

    Schank, Roger C; Riesbeck, Christopher K

    2014-01-01

    This book is the third volume in a series that provides a hands-on perspective on the evolving theories associated with Roger Schank and his students. The primary focus of this volume is on constructing explanations. All of the chapters relate to the problem of building computer programs that can develop hypotheses about what might have caused an observed event. Because most researchers in natural language processing don't really want to work on inference, memory, and learning issues, most of their sample text fragments are chosen carefully to de-emphasize the need for non text-related reasoni

  5. A neurophysiological approach to tinnitus: clinical implications.

    Science.gov (United States)

    Jastreboff, P J; Hazell, J W

    1993-02-01

    This paper presents a neurophysiological approach to tinnitus and discusses its clinical implications. A hypothesis of discordant damage of inner and outer hair cells systems in tinnitus generation is outlined. A recent animal model has facilitated the investigation of the mechanisms of tinnitus and has been further refined to allow for the measurement of tinnitus pitch and loudness. The analysis of the processes involved in tinnitus detection postulates the involvement of an abnormal increase of gain within the auditory system. Moreover, it provides a basis for treating patients with hyperacusis, which we are considering to be a pre-tinnitus state. Analysis of the process of tinnitus perception allows for the possibility of facilitating the process of tinnitus habituation for the purpose of its alleviation. The combining of theoretical analysis with clinical findings has resulted in the creation of a multidisciplinary Tinnitus Centre. The foundation of the Centre focuses on two goals: the clinical goal is to remove tinnitus perception from the patient's consciousness, while directing research toward finding a mechanism-based method for the suppression of tinnitus generators and processes responsible for enhancement of tinnitus-related neuronal activity.

  6. Neurophysiology of Drosophila Models of Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Ryan J. H. West

    2015-01-01

    Full Text Available We provide an insight into the role Drosophila has played in elucidating neurophysiological perturbations associated with Parkinson’s disease- (PD- related genes. Synaptic signalling deficits are observed in motor, central, and sensory systems. Given the neurological impact of disease causing mutations within these same genes in humans the phenotypes observed in fly are of significant interest. As such we observe four unique opportunities provided by fly nervous system models of Parkinson’s disease. Firstly, Drosophila models are instrumental in exploring the mechanisms of neurodegeneration, with several PD-related mutations eliciting related phenotypes including sensitivity to energy supply and vesicular deformities. These are leading to the identification of plausible cellular mechanisms, which may be specific to (dopaminergic neurons and synapses rather than general cellular phenotypes. Secondly, models show noncell autonomous signalling within the nervous system, offering the opportunity to develop our understanding of the way pathogenic signalling propagates, resembling Braak’s scheme of spreading pathology in PD. Thirdly, the models link physiological deficits to changes in synaptic structure. While the structure-function relationship is complex, the genetic tractability of Drosophila offers the chance to separate fundamental changes from downstream consequences. Finally, the strong neuronal phenotypes permit relevant first in vivo drug testing.

  7. Suprasegmental neurophysiological monitoring with H reflex and TcMEP in spinal surgery. Transient loss due to hypotension. A case report

    Directory of Open Access Journals (Sweden)

    Ángel Saponaro-González

    Full Text Available Objective: H-reflex is a well known neurophysiological test used to evaluate sensory afferent and motor efferent impulses of S1 root. Despite its simplicity and feasibility, it is not used very often in the operating room. Methods: We report the case of a 16-year-old male patient who undergoes a surgical correction for a severe paralytic scoliosis (160°. On account of previous deficits, intraoperative neurophysiological monitoring was achieved through TcMEP and H-reflex. Results: Intraoperative neurophysiological monitoring (IONM showed a transient and simultaneous loss of bilateral TcMEP and H-reflex, coinciding with an abrupt hypotension during pedicle screw placement. After having dismissed mechanical injury and after increasing blood pressure, TcMEP and H-reflex were equivalent to those at baseline. Conclusions: The H-reflex is a classic neurophysiological test not used very frequently in the operating room. It is a feasible and reliable technique that can be helpful during spine surgery IONM, especially in patients with preexisting neurological deficits. Although simultaneous TcMEP and H-reflex monitoring has been previously described, to our knowledge, this is the first recorded case of a decline in both associated with abrupt hypotension. Keywords: Intraoperative neurophysiological monitoring, TcMEP, H-reflex, Scoliosis, Hypotension

  8. Thorough specification of the neurophysiologic processes underlying behavior and of their manifestation in EEG - demonstration with the go/no-go task.

    Science.gov (United States)

    Shahaf, Goded; Pratt, Hillel

    2013-01-01

    In this work we demonstrate the principles of a systematic modeling approach of the neurophysiologic processes underlying a behavioral function. The modeling is based upon a flexible simulation tool, which enables parametric specification of the underlying neurophysiologic characteristics. While the impact of selecting specific parameters is of interest, in this work we focus on the insights, which emerge from rather accepted assumptions regarding neuronal representation. We show that harnessing of even such simple assumptions enables the derivation of significant insights regarding the nature of the neurophysiologic processes underlying behavior. We demonstrate our approach in some detail by modeling the behavioral go/no-go task. We further demonstrate the practical significance of this simplified modeling approach in interpreting experimental data - the manifestation of these processes in the EEG and ERP literature of normal and abnormal (ADHD) function, as well as with comprehensive relevant ERP data analysis. In-fact we show that from the model-based spatiotemporal segregation of the processes, it is possible to derive simple and yet effective and theory-based EEG markers differentiating normal and ADHD subjects. We summarize by claiming that the neurophysiologic processes modeled for the go/no-go task are part of a limited set of neurophysiologic processes which underlie, in a variety of combinations, any behavioral function with measurable operational definition. Such neurophysiologic processes could be sampled directly from EEG on the basis of model-based spatiotemporal segregation.

  9. Assessing fitness-for-duty and predicting performance with cognitive neurophysiological measures

    Science.gov (United States)

    Smith, Michael E.; Gevins, Alan

    2005-05-01

    Progress is described in developing a novel test of neurocognitive status for fitness-for-duty testing. The Sustained Attention & Memory (SAM) test combines neurophysiologic (EEG) measures of brain activation with performance measures during a psychometric test of sustained attention and working memory, and then gauges changes in neurocognitive status relative to an individual"s normative baseline. In studies of the effects of common psychoactive substances that can affect job performance, including sedating antihistamines, caffeine, alcohol, marijuana, and prescription medications, test sensitivity was greater for the combined neurophysiological and performance measures than for task performance measures by themselves. The neurocognitive effects of overnight sleep deprivation were quite evident, and such effects predicted subsequent performance impairment on a flight simulator task. Sensitivity to diurnal circadian variations was also demonstrated. With further refinement and independent validation, the SAM Test may prove useful for assessing readiness-to-perform in high-asset personnel working in demanding, high risk situations.

  10. Is appreciation of written education about pain neurophysiology related to changes in illness perceptions and health status in patients with fibromyalgia?

    NARCIS (Netherlands)

    van Ittersum, M. W.; van Wilgen, C. P.; Groothoff, J. W.; van der Schans, C. P.

    2011-01-01

    Objective: To investigate the appreciation of written education about pain neurophysiology in patients with fibromyalgia (FM) and its effects on illness perceptions and perceived health status. Methods: A booklet explaining pain neurophysiology was sent to participants with FM. Appreciation was

  11. Is appreciation of written education about pain neurophysiology related to changes in illness perceptions and health status in patients with fibromyalgia?

    NARCIS (Netherlands)

    van Ittersum, Miriam; van Wilgen, C P; Groothoff, J W; van der Schans, C.P.

    2011-01-01

    OBJECTIVE: To investigate the appreciation of written education about pain neurophysiology in patients with fibromyalgia (FM) and its effects on illness perceptions and perceived health status. METHODS: A booklet explaining pain neurophysiology was sent to participants with FM. Appreciation was

  12. Is appreciation of written education about pain neurophysiology related to changes in illness perceptions and health status in patients with fibromyalgia?

    NARCIS (Netherlands)

    van Ittersum, M. W.; van Wilgen, C. P.; Groothoff, J. W.; van der Schans, C. P.

    2011-01-01

    To investigate the appreciation of written education about pain neurophysiology in patients with fibromyalgia (FM) and its effects on illness perceptions and perceived health status. A booklet explaining pain neurophysiology was sent to participants with FM. Appreciation was assessed with 10

  13. Neurophysiological correlates of word processing deficits in isolated reading and isolated spelling disorders.

    Science.gov (United States)

    Bakos, Sarolta; Landerl, Karin; Bartling, Jürgen; Schulte-Körne, Gerd; Moll, Kristina

    2018-03-01

    In consistent orthographies, isolated reading disorders (iRD) and isolated spelling disorders (iSD) are nearly as common as combined reading-spelling disorders (cRSD). However, the exact nature of the underlying word processing deficits in isolated versus combined literacy deficits are not well understood yet. We applied a phonological lexical decision task (including words, pseudohomophones, legal and illegal pseudowords) during ERP recording to investigate the neurophysiological correlates of lexical and sublexical word-processing in children with iRD, iSD and cRSD compared to typically developing (TD) 9-year-olds. TD children showed enhanced early sensitivity (N170) for word material and for the violation of orthographic rules compared to the other groups. Lexical orthographic effects (higher LPC amplitude for words than for pseudohomophones) were the same in the TD and iRD groups, although processing took longer in children with iRD. In the iSD and cRSD groups, lexical orthographic effects were evident and stable over time only for correctly spelled words. Orthographic representations were intact in iRD children, but word processing took longer compared to TD. Children with spelling disorders had partly missing orthographic representations. Our study is the first to specify the underlying neurophysiology of word processing deficits associated with isolated literacy deficits. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  14. Monitoring Brain Activity of Geriatric Learners with Low-Cost Neurophysiological Technology

    Science.gov (United States)

    Romero-Hall, Enilda; Scott, JoAnne

    2017-01-01

    Cultural stereotypes rooted in both antiquated data and misinterpretation of data have long perpetuated the belief that older adults are unable to learn new concepts because they are doomed to lose brain cells at an alarming rate during their geriatric years. However, advances in neurophysiological technologies that allow researchers to observe…

  15. The effect of task demand and incentive on neurophysiological and cardiovascular markers of effort.

    Science.gov (United States)

    Fairclough, Stephen H; Ewing, Kate

    2017-09-01

    According to motivational intensity theory, effort is proportional to the level of task demand provided that success is possible and successful performance is deemed worthwhile. The current study represents a simultaneous manipulation of demand (working memory load) and success importance (financial incentive) to investigate neurophysiological (EEG) and cardiovascular measures of effort. A 2×2 repeated-measures study was conducted where 18 participants performed a n-back task under three conditions of demand: easy (1-back), hard (4-back) and very hard (7-back). In addition, participants performed these tasks in the presence of performance-contingent financial incentive or in a no-incentive (pilot trial) condition. Three bands of EEG activity were quantified: theta (4-7Hz), lower-alpha (7.5-10Hz) and upper-alpha (10.5-13Hz). Fronto-medial activity in the theta band and activity in the upper-alpha band at frontal, central and parietal sites were sensitive to demand and indicated greatest effort when the task was challenging and success was possible. Mean systolic blood pressure and activity in the lower-alpha band at parietal sites were also sensitive to demand but also increased in the incentive condition across all levels of task demand. The results of the study largely support the predictions of motivational intensity using neurophysiological markers of effort. Copyright © 2017. Published by Elsevier B.V.

  16. A portable platform to collect and review behavioral data simultaneously with neurophysiological signals.

    Science.gov (United States)

    Tianxiao Jiang; Siddiqui, Hasan; Ray, Shruti; Asman, Priscella; Ozturk, Musa; Ince, Nuri F

    2017-07-01

    This paper presents a portable platform to collect and review behavioral data simultaneously with neurophysiological signals. The whole system is comprised of four parts: a sensor data acquisition interface, a socket server for real-time data streaming, a Simulink system for real-time processing and an offline data review and analysis toolbox. A low-cost microcontroller is used to acquire data from external sensors such as accelerometer and hand dynamometer. The micro-controller transfers the data either directly through USB or wirelessly through a bluetooth module to a data server written in C++ for MS Windows OS. The data server also interfaces with the digital glove and captures HD video from webcam. The acquired sensor data are streamed under User Datagram Protocol (UDP) to other applications such as Simulink/Matlab for real-time analysis and recording. Neurophysiological signals such as electroencephalography (EEG), electrocorticography (ECoG) and local field potential (LFP) recordings can be collected simultaneously in Simulink and fused with behavioral data. In addition, we developed a customized Matlab Graphical User Interface (GUI) software to review, annotate and analyze the data offline. The software provides a fast, user-friendly data visualization environment with synchronized video playback feature. The software is also capable of reviewing long-term neural recordings. Other featured functions such as fast preprocessing with multithreaded filters, annotation, montage selection, power-spectral density (PSD) estimate, time-frequency map and spatial spectral map are also implemented.

  17. NEUROPHYSIOLOGY PARAMETERS IN DIAGNOSTICS OF MULTIPLE SCLEROSIS AND ACUTE DISSEMINATED ENCEPHALOMYELITIS IN CHILDREN

    Directory of Open Access Journals (Sweden)

    V. B. Voitenkov

    2017-01-01

    Full Text Available Our research objective was to evaluate the importance of neurophysiological methods in diagnosing the state of visual, somatosensory and motor pathways condition in the early stages of multiple sclerosis (MS and acute disseminated encephalomyelitis (ADEM in children.Materials and methods. Twenty-four children with a debut of multiple sclerosis, 15 children with debute of acute disseminated encephalomyelitis and 20 neurologically healthy children of the comparison group were examined. All patients were evaluated by neurologist, brain MRI and CSF analysis (isoelectrofocusing to oligoclonal IgG, oligoclonal bands test, visual evoked potentials (VEP, transcranial magnetic stimulation (TMS and somatosensory evoked potentials (SSEP.Results. In children with MS asymmetry of the conduction along the motor pathways on the spinal level was higher than in patients with ADEM and controls, functional state of somatosensory cortex neurons was lower and conduction along somatosensory pathways on the spinal level was slower – all differences significant. According to the visual evoked potentials, in more than half of the cases, there was an increase in the latency of the P100 peak. Also in MS group there was a significant disruption of the visual pathway in 54% of the cases. Neurophysiological changes in 58% of cases were demyelinating, and violations of the axonal type occurred in 37% of cases.Conclusions. Neurophysiological diagnostic methods such as transcranial magnetic stimulation, visual evoked potentials, somatosensory evoked potentials are highly informative for the differential diagnosis of multiple sclerosis and acute disseminated encephalomyelitis. More pronounced spinal lesions in early stages of MS than in ADEM in children may be the cause of the neurophysiologic differences, and prevalence of the sensory system involvement at this stage may be the reason behind more extended SSEP abnormalities comparing with TMS. VEP changes may reflect primary

  18. Early neurophysiological indices of second language morphosyntax learning.

    Science.gov (United States)

    Hanna, Jeff; Shtyrov, Yury; Williams, John; Pulvermüller, Friedemann

    2016-02-01

    Humans show variable degrees of success in acquiring a second language (L2). In many cases, morphological and syntactic knowledge remain deficient, although some learners succeed in reaching nativelike levels, even if they begin acquiring their L2 relatively late. In this study, we use psycholinguistic, online language proficiency tests and a neurophysiological index of syntactic processing, the syntactic mismatch negativity (sMMN) to local agreement violations, to compare behavioural and neurophysiological markers of grammar processing between native speakers (NS) of English and non-native speakers (NNS). Variable grammar proficiency was measured by psycholinguistic tests. When NS heard ungrammatical word sequences lacking agreement between subject and verb (e.g. *we kicks), the MMN was enhanced compared with syntactically legal sentences (e.g. he kicks). More proficient NNS also showed this difference, but less proficient NNS did not. The main cortical sources of the MMN responses were localised in bilateral superior temporal areas, where, crucially, source strength of grammar-related neuronal activity correlated significantly with grammatical proficiency of individual L2 speakers as revealed by the psycholinguistic tests. As our results show similar, early MMN indices to morpho-syntactic agreement violations among both native speakers and non-native speakers with high grammar proficiency, they appear consistent with the use of similar brain mechanisms for at least certain aspects of L1 and L2 grammars. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Influence of neurophysiological hippotherapy on the transference of the centre of gravity among children with cerebral palsy.

    Science.gov (United States)

    Maćków, Anna; Małachowska-Sobieska, Monika; Demczuk-Włodarczyk, Ewa; Sidorowska, Marta; Szklarska, Alicja; Lipowicz, Anna

    2014-01-01

    The aim of the study was to present the influence of neurophysiological hippotherapy on the transference of the centre of gravity (COG) among children with cerebral palsy (CP). The study involved 19 children aged 4-13 years suffering from CP who demonstrated an asymmetric (A/P) model of compensation. Body balance was studied with the Cosmogamma Balance Platform. An examination on this platform was performed before and after a session of neurophysiological hippotherapy. In order to compare the correlations and differences between the examinations, the results were analysed using Student's T-test for dependent samples at p ≤ 0.05 as the level of statistical significance and descriptive statistics were calculated. The mean value of the body's centre of gravity in the frontal plane (COG X) was 18.33 (mm) during the first examination, changing by 21.84 (mm) after neurophysiological hippotherapy towards deloading of the antigravity lower limb (p ≤ 0.0001). The other stabilographic parameters increased; however, only the change in average speed of antero - posterior COG oscillation was statistically significant (p = 0.0354). 1. One session of neurophysiological hippotherapy induced statistically significant changes in the position of the centre of gravity in the body in the frontal plane and the average speed of COG oscillation in the sagittal plane among CP children demonstrating an asymmetric model of compensation (A/P).

  20. Qualitative explanations for red giant formation

    International Nuclear Information System (INIS)

    Bhaskar, R.; Nigam, A.

    1991-01-01

    Recent research on giant formation has focused on the need for qualitative explanations. The explanations have the following general, qualitative form: the polytrope n assumes a certain value, that makes (d ln r)/(d ln z) take on a very large value; large increases in r can then be explained in terms of small changes in the variable z. This form is applicable to all the explanations current in the literature: they all have (1) either implicitly or explicitly, both a hydrostatic component and a luminosity-opacity component, and (2) a reliance on singular solutions. Dimensional analysis reveals that power laws that assume the polytrope n to 5 are identical in both the hydrostatic and luminosity-based explanations. 12 refs

  1. Characterization of neurophysiologic and neurocognitive biomarkers for use in genomic and clinical outcome studies of schizophrenia.

    Directory of Open Access Journals (Sweden)

    Gregory A Light

    Full Text Available Endophenotypes are quantitative, laboratory-based measures representing intermediate links in the pathways between genetic variation and the clinical expression of a disorder. Ideal endophenotypes exhibit deficits in patients, are stable over time and across shifts in psychopathology, and are suitable for repeat testing. Unfortunately, many leading candidate endophenotypes in schizophrenia have not been fully characterized simultaneously in large cohorts of patients and controls across these properties. The objectives of this study were to characterize the extent to which widely-used neurophysiological and neurocognitive endophenotypes are: 1 associated with schizophrenia, 2 stable over time, independent of state-related changes, and 3 free of potential practice/maturation or differential attrition effects in schizophrenia patients (SZ and nonpsychiatric comparison subjects (NCS. Stability of clinical and functional measures was also assessed.Participants (SZ n = 341; NCS n = 205 completed a battery of neurophysiological (MMN, P3a, P50 and N100 indices, PPI, startle habituation, antisaccade, neurocognitive (WRAT-3 Reading, LNS-forward, LNS-reorder, WCST-64, CVLT-II. In addition, patients were rated on clinical symptom severity as well as functional capacity and status measures (GAF, UPSA, SOF. 223 subjects (SZ n = 163; NCS n = 58 returned for retesting after 1 year.Most neurophysiological and neurocognitive measures exhibited medium-to-large deficits in schizophrenia, moderate-to-substantial stability across the retest interval, and were independent of fluctuations in clinical status. Clinical symptoms and functional measures also exhibited substantial stability. A Longitudinal Endophenotype Ranking System (LERS was created to rank neurophysiological and neurocognitive biomarkers according to their effect sizes across endophenotype criteria.The majority of neurophysiological and neurocognitive measures exhibited deficits in

  2. Characterization of neurophysiologic and neurocognitive biomarkers for use in genomic and clinical outcome studies of schizophrenia.

    Science.gov (United States)

    Light, Gregory A; Swerdlow, Neal R; Rissling, Anthony J; Radant, Allen; Sugar, Catherine A; Sprock, Joyce; Pela, Marlena; Geyer, Mark A; Braff, David L

    2012-01-01

    Endophenotypes are quantitative, laboratory-based measures representing intermediate links in the pathways between genetic variation and the clinical expression of a disorder. Ideal endophenotypes exhibit deficits in patients, are stable over time and across shifts in psychopathology, and are suitable for repeat testing. Unfortunately, many leading candidate endophenotypes in schizophrenia have not been fully characterized simultaneously in large cohorts of patients and controls across these properties. The objectives of this study were to characterize the extent to which widely-used neurophysiological and neurocognitive endophenotypes are: 1) associated with schizophrenia, 2) stable over time, independent of state-related changes, and 3) free of potential practice/maturation or differential attrition effects in schizophrenia patients (SZ) and nonpsychiatric comparison subjects (NCS). Stability of clinical and functional measures was also assessed. Participants (SZ n = 341; NCS n = 205) completed a battery of neurophysiological (MMN, P3a, P50 and N100 indices, PPI, startle habituation, antisaccade), neurocognitive (WRAT-3 Reading, LNS-forward, LNS-reorder, WCST-64, CVLT-II). In addition, patients were rated on clinical symptom severity as well as functional capacity and status measures (GAF, UPSA, SOF). 223 subjects (SZ n = 163; NCS n = 58) returned for retesting after 1 year. Most neurophysiological and neurocognitive measures exhibited medium-to-large deficits in schizophrenia, moderate-to-substantial stability across the retest interval, and were independent of fluctuations in clinical status. Clinical symptoms and functional measures also exhibited substantial stability. A Longitudinal Endophenotype Ranking System (LERS) was created to rank neurophysiological and neurocognitive biomarkers according to their effect sizes across endophenotype criteria. The majority of neurophysiological and neurocognitive measures exhibited deficits in patients

  3. Circadian Rhythm Control: Neurophysiological Investigations

    Science.gov (United States)

    Glotzbach, S. F.

    1985-01-01

    The suprachiasmatic nucleus (SCN) was implicated as a primary component in central nervous system mechanisms governing circadian rhythms. Disruption of the normal synchronization of temperature, activity, and other rhythms is detrimental to health. Sleep wake disorders, decreases in vigilance and performance, and certain affective disorders may result from or be exacerbated by such desynchronization. To study the basic neurophysiological mechanisms involved in entrainment of circadian systems by the environment, Parylene-coated, etched microwire electrode bundles were used to record extracellular action potentials from the small somata of the SCN and neighboring hypothalamic nuclei in unanesthetized, behaving animals. Male Wistar rats were anesthetized and chronically prepared with EEG ane EMG electrodes in addition to a moveable microdrive assembly. The majority of cells had firing rates 10 Hz and distinct populations of cells which had either the highest firing rate or lowest firing rate during sleep were seen.

  4. Neurophysiological processes and functional neuroanatomical structures underlying proactive effects of emotional conflicts.

    Science.gov (United States)

    Schreiter, Marie Luise; Chmielewski, Witold; Beste, Christian

    2018-07-01

    There is a strong inter-relation of cognitive and emotional processes as evidenced by emotional conflict monitoring processes. In the cognitive domain, proactive effects of conflicts have widely been studied; i.e. effects of conflicts in the n-1 trial on trial n. Yet, the neurophysiological processes and associated functional neuroanatomical structures underlying such proactive effects during emotional conflicts have not been investigated. This is done in the current study combining EEG recordings with signal decomposition methods and source localization approaches. We show that an emotional conflict in the n-1 trial differentially influences processing of positive and negative emotions in trial n, but not the processing of conflicts in trial n. The dual competition framework stresses the importance of dissociable 'perceptual' and 'response selection' or cognitive control levels for interactive effects of cognition and emotion. Only once these coding levels were isolated in the neurophysiological data, processes explaining the behavioral effects were detectable. The data show that there is not only a close correspondence between theoretical propositions of the dual competition framework and neurophysiological processes. Rather, processing levels conceptualized in the framework operate in overlapping time windows, but are implemented via distinct functional neuroanatomical structures; the precuneus (BA31) and the insula (BA13). It seems that decoding of information in the precuneus, as well as the integration of information during response selection in the insula is more difficult when confronted with angry facial emotions whenever cognitive control resources have been highly taxed by previous conflicts. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Motivated Explanation

    Directory of Open Access Journals (Sweden)

    Richard ePatterson

    2015-10-01

    Full Text Available Although motivation is a well-established field of study in its own right, and has been fruitfully studied in connection with attribution theory and belief formation under the heading of motivated thinking, its powerful and pervasive influence on explanatory processes is less well explored. Where one has a strong motivation to understand some event correctly, one is thereby motivated to adhere as best one can to normative or epistemic criteria for correct or accurate explanation, even if one does not consciously formulate or apply such criteria. By contrast, many of our motivations to explain introduce bias into the processes involved in generating, evaluating, or giving of explanations. Non-epistemic explanatory motivations, or (following Kunda’s usage, directional motivations, include self-justification, resolution of cognitive dissonance, deliberate deception, teaching, and many more. Some of these motivations lead to the relaxation or violation of epistemic norms, combined with an effort to preserve the appearance of accuracy; others enhance epistemic motivation, so that one engages in more careful and thorough generational and evaluative processes. In short, real life explanatory processes are often constrained by multiple goals, epistemic and directional, where these goals may mutually reinforce one another or may conflict, and where our explanations emerge as a matter of weighing and satisfying those goals. Our proposals are largely programmatic, although we do review a good deal of relevant behavioral and neurological evidence. Specifically, we recognize five generative processes, some of which cover further sub-processes, and six evaluative processes. All of these are potential points of entry for the influence of motivation. We then suggest in some detail how specific sorts of explanatory motivation interact with specific explanatory processes.

  6. Social Consumer Neuroscience: Neurophysiological Measures of Advertising Effectiveness in a Social Context

    NARCIS (Netherlands)

    R. Pozharliev (Rumen); W.J.M.I. Verbeke (Willem); R.P. Bagozzi (Richard)

    2017-01-01

    textabstractThe application of neurophysiological methods to study the effects of advertising on consumer purchase behavior has seen an enormous growth in recent years. However, little is known about the role social settings have on shaping the human brain during the processing of advertising

  7. Multimodal neurophysiological and psychometric evaluation among patients with systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Shehata GA

    2011-04-01

    Full Text Available Ghaydaa A Shehata1, Yasser MB Elserogy2, Hossam Eddin K Ahmad2, Mohamed I Abdel-Kareem3, Ashraf M Al-kabeer4, Mohamed M Rayan2, Mohamed ES Abd El-Baky 1Department of Neurology; 2Department of Psychiatry, Assiut University, Egypt; 3Department of Rheumatology, Physical Medicine and Rehabilitation; 4Department of Internal Medicine, Faculty of Medicine, Al-Azhar University, Assiut, EgyptObjective: To determine some of the neuropsychiatric manifestations of systemic lupus erythematosus (SLE by applying multimodal neurophysiological and psychometric studies.Patients and methods: Twenty-six SLE patients were evaluated for neurological and psychiatric disorders and compared with 26 healthy controls matched for age, sex, education, and social class. The severity of SLE disease was assessed. Each subject was subjected to the following examinations: laboratory, neurophysiology, magnetic resonance imaging of the brain, transcranial duplex, Modified Mini-mental State Examination, Cognitive Assessment Scale Inventory, Hamilton Depression Scale, and Hamilton Anxiety Scale.Results: The mean age of subjects was 25.9 ± 8.9 years. The most prevalent neurological manifestations were (in order of frequency anxiety in 17 cases (65.4%, depression in 15 cases (57.7%, headache in 10 cases (38.5%, peripheral neuropathy in 7 cases (26.9%, seizures in 6 cases (23.1%, psychosis in 5 cases (19.2%, dementia in 4 cases (15.4%, radiculopathy in 4 cases (15.4%, myositis in 3 cases (11.5%, and stroke in 2 cases (7.7%. There was a significant affection in amplitude of the ulnar nerve, cognitive function impairment, and electroencephalography changes. There was a significant increased mean velocity and decreased Pulsatility Index of the most studied intracranial vessels in the patients.Conclusion: The use of multimodal neurophysiological, transcranial duplex, and psychometric scales increases the sensitivity for detecting nervous system involvement.Keywords: SLE, SLEDAI

  8. Behavioral guides for sensory neurophysiology.

    Science.gov (United States)

    Konishi, M

    2006-06-01

    The study of natural behavior is important for understanding the coding schemes of sensory systems. The jamming avoidance response of the weakly electric fish Eigenmannia is an excellent example of a bottom-up approach, in which behavioral analyses guided neurophysiological studies. These studies started from the electroreceptive sense organs to the motor output consisting of pacemaker neurons. Going in the opposite direction, from the central nervous system to lower centers, is the characteristic of the top-down approach. Although this approach is perhaps more difficult than the bottom-up approach, it was successfully employed in the neuroethological analysis of sound localization in the barn owl. In the latter studies, high-order neurons selective for complex natural stimuli led to the discovery of neural pathways and networks responsible for the genesis of the stimulus selectivity. Comparison of Eigenmannia and barn owls, and their neural systems, has revealed similarities in network designs, such as parallel pathways and their convergence to produce stimulus selectivity necessary for detection of natural stimuli.

  9. Learning from instructional explanations: effects of prompts based on the active-constructive-interactive framework.

    Science.gov (United States)

    Roelle, Julian; Müller, Claudia; Roelle, Detlev; Berthold, Kirsten

    2015-01-01

    Although instructional explanations are commonly provided when learners are introduced to new content, they often fail because they are not integrated into effective learning activities. The recently introduced active-constructive-interactive framework posits an effectiveness hierarchy in which interactive learning activities are at the top; these are then followed by constructive and active learning activities, respectively. Against this background, we combined instructional explanations with different types of prompts that were designed to elicit these learning activities and tested the central predictions of the active-constructive-interactive framework. In Experiment 1, N = 83 students were randomly assigned to one of four combinations of instructional explanations and prompts. To test the active learning hypothesis, the learners received either (1) complete explanations and engaging prompts designed to elicit active activities or (2) explanations that were reduced by inferences and inference prompts designed to engage learners in constructing the withheld information. Furthermore, in order to explore how interactive learning activities can be elicited, we gave the learners who had difficulties in constructing the prompted inferences adapted remedial explanations with either (3) unspecific engaging prompts or (4) revision prompts. In support of the active learning hypothesis, we found that the learners who received reduced explanations and inference prompts outperformed the learners who received complete explanations and engaging prompts. Moreover, revision prompts were more effective in eliciting interactive learning activities than engaging prompts. In Experiment 2, N = 40 students were randomly assigned to either (1) a reduced explanations and inference prompts or (2) a reduced explanations and inference prompts plus adapted remedial explanations and revision prompts condition. In support of the constructive learning hypothesis, the learners who received

  10. The neurophysiology of human touch and eye gaze and its effects on therapeutic relationships and healing: a scoping review protocol.

    Science.gov (United States)

    Kerr, Fiona; Wiechula, Rick; Feo, Rebecca; Schultz, Tim; Kitson, Alison

    2016-04-01

    The objective of this scoping review is to examine and map the range of neurophysiological impacts of human touch and eye gaze, and better understand their possible links to the therapeutic relationship and the process of healing. The specific question is "what neurophysiological impacts of human touch and eye gaze have been reported in relation to therapeutic relationships and healing?"

  11. Neurophysiology and Neuroanatomy of Reflexive and Voluntary Saccades in Non-Human Primates

    Science.gov (United States)

    Johnston, Kevin; Everling, Stefan

    2008-01-01

    A multitude of cognitive functions can easily be tested by a number of relatively simple saccadic eye movement tasks. This approach has been employed extensively with patient populations to investigate the functional deficits associated with psychiatric disorders. Neurophysiological studies in non-human primates performing the same tasks have…

  12. Modes of risk explanation in telephone consultations between nurses and parents for a genetic condition

    DEFF Research Database (Denmark)

    Zayts, Olga; Sarangi, Srikant

    2013-01-01

    as warrants for advice-giving and providing reassurance. We then examine how the genetic nurses interactionally orient themselves to the parents’ existing knowledge regarding G6PD deficiency while delivering these risk explanations. The differences in explanation trajectories are linked to the presence...

  13. Neurophysiological features of Internet gaming disorder and alcohol use disorder: a resting-state EEG study.

    Science.gov (United States)

    Son, K-L; Choi, J-S; Lee, J; Park, S M; Lim, J-A; Lee, J Y; Kim, S N; Oh, S; Kim, D J; Kwon, J S

    2015-09-01

    Despite that Internet gaming disorder (IGD) shares clinical, neuropsychological and personality characteristics with alcohol use disorder (AUD), little is known about the resting-state quantitative electroencephalography (QEEG) patterns associated with IGD and AUD. Therefore, this study compared the QEEG patterns in patients with IGD with those in patients with AUD to identify unique neurophysiological characteristics that can be used as biomarkers of IGD. A total of 76 subjects (34 with IGD, 17 with AUD and 25 healthy controls) participated in this study. Resting-state, eyes-closed QEEGs were recorded, and the absolute and relative power of brains were analyzed. The generalized estimating equation showed that the IGD group had lower absolute beta power than AUD (estimate = 5.319, P < 0.01) and the healthy control group (estimate = 2.612, P = 0.01). The AUD group showed higher absolute delta power than IGD (estimate = 7.516, P < 0.01) and the healthy control group (estimate = 7.179, P < 0.01). We found no significant correlations between the severity of IGD and QEEG activities in patients with IGD. The current findings suggest that lower absolute beta power can be used as a potential trait marker of IGD. Higher absolute power in the delta band may be a susceptibility marker for AUD. This study clarifies the unique characteristics of IGD as a behavioral addiction, which is distinct from AUD, by providing neurophysiological evidence.

  14. WPPSS debacle: explanations and lessons

    International Nuclear Information System (INIS)

    Meyer, M.B.

    1984-01-01

    Principal explanations for the WPPSS events to date can be more or less satisfactorily derived. Five explanations appear to dominate: (1) the long and previously successful history of public power in the Pacific Northwest; (2) overoptimism by architect/engineers and consulting engineers about construction costs and construction durations; (3) laxness by bond counsel in scrutinizing and disclosing potential legal impediments to the various transactions involved; (4) WPPSS easy access to capital markets, combined with naivete in those markets; and (5) the inability of WPPSS to manage and oversee the construction process. This paper explains the specific reasons for, and the importance of, each of these five explanations for the WPPSS debacle. It then develops lessons and conclusions for the future which can be derived from this debacle. 12 references

  15. [Anaesthetic management of excision of a cervical intraspinal tumor with intraoperative neurophysiologic monitoring in a pregnant woman at 29 weeks].

    Science.gov (United States)

    Guerrero-Domínguez, R; González-González, G; Rubio-Romero, R; Federero-Martínez, F; Jiménez, I

    2016-05-01

    The intraoperative neurophysiological monitoring is a technique used to test and monitor nervous function. This technique has become essential in some neurosurgery interventions, since it avoids neurological injuries during surgery and reduces morbidity. The experience of intraoperative neurophysiological monitoring is limited in some clinical cases due to the low incidence of pregnant women undergoing a surgical procedure. A case is presented of a 29-weeks pregnant woman suffering from a cervical intraspinal tumour with intense pain, which required surgery. The collaboration of a multidisciplinary team composed of anaesthesiologists, neurosurgeons, neurophysiologists and obstetricians, the continuous monitoring of the foetus, the intraoperative neurophysiological monitoring, and maintaining the neurophysiological and utero-placental variables were crucial for the proper development of the surgery. According to our experience and the limited publications in the literature, no damaging effects of this technique were detected at maternal-foetal level. On the contrary, it brings important benefits during the surgery and for the final result. Copyright © 2015 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Scientific Explanations and Piagetian Operational Levels.

    Science.gov (United States)

    Bass, Joel E.; Maddux, Cleborne D.

    1982-01-01

    Examined effects of operational levels of ninth-grade (N=16) and college (N=40) students on causal explanations they recalled after instruction. Results indicate concrete/formal students recalled explanations requiring chaining of two implication statements while formal subjects outperformed concrete subjects in reconstruction of complex…

  17. The effect of L-dopa in Parkinson's disease as revealed by neurophysiological studies of motor and sensory functions.

    Science.gov (United States)

    Suppa, Antonio; Bologna, Matteo; Conte, Antonella; Berardelli, Alfredo; Fabbrini, Giovanni

    2017-02-01

    This review will first discuss evidence of motor and sensory abnormalities as yielded by neurophysiological techniques in patients with PD. It will then go on to describe the effects of L-dopa replacement on motor and sensory abnormalities in PD as assessed by neurophysiological studies. Areas covered: We analyzed papers in English using Pubmed with the following keywords: L-dopa, dopamine, bradykinesia, basal ganglia, kinematic analysis, TMS, motor cortex plasticity, motor cortex excitability, somatosensory discrimination threshold, pain Expert commentary: L-dopa improves the amplitude and speed of upper limb voluntary movements, but it does not restore abnormalities in the sequence effect or voluntary facial movements. L-dopa only partially normalizes changes in motor cortex excitability and plasticity and has also contrasting effects on the sensory system and on sensory-motor integration. The neurophysiological studies reviewed here show that PD is more than a hypo-dopaminergic disease, and non-dopaminergic mechanisms should also be considered.

  18. Using pupil size and heart rate to infer affective states during behavioral neurophysiology and neuropsychology experiments.

    Science.gov (United States)

    Mitz, Andrew R; Chacko, Ravi V; Putnam, Philip T; Rudebeck, Peter H; Murray, Elisabeth A

    2017-03-01

    Nonhuman primates (NHPs) are a valuable research model because of their behavioral, physiological and neuroanatomical similarities to humans. In the absence of language, autonomic activity can provide crucial information about cognitive and affective states during single-unit recording, inactivation and lesion studies. Methods standardized for use in humans are not easily adapted to NHPs and detailed guidance has been lacking. We provide guidance for monitoring heart rate and pupil size in the behavioral neurophysiology setting by addressing the methodological issues, pitfalls and solutions for NHP studies. The methods are based on comparative physiology to establish a rationale for each solution. We include examples from both electrophysiological and lesion studies. Single-unit recording, pupil responses and heart rate changes represent a range of decreasing temporal resolution, a characteristic that impacts experimental design and analysis. We demonstrate the unexpected result that autonomic measures acquired before and after amygdala lesions are comparable despite disruption of normal autonomic function. Species and study design differences can render standard techniques used in human studies inappropriate for NHP studies. We show how to manage data from small groups typical of NHP studies, data from the short behavioral trials typical of neurophysiological studies, issues associated with longitudinal studies, and differences in anatomy and physiology. Autonomic measurement to infer cognitive and affective states in NHP is neither off-the-shelf nor onerous. Familiarity with the issues and solutions will broaden the use of autonomic signals in NHP single unit and lesion studies. Published by Elsevier B.V.

  19. A Teaching Model for Scaffolding 4th Grade Students' Scientific Explanation Writing

    Science.gov (United States)

    Yang, Hsiu-Ting; Wang, Kuo-Hua

    2014-08-01

    Improving students scientific explanations is one major goal of science education. Both writing activities and concept mapping are reported as effective strategies for enhancing student learning of science. The purpose of this study was to examine the effect of a teaching model, named the DCI model, which integrates a Descriptive explanation writing activity, Concept mapping, and an Interpretive explanation writing activity, is introduced in a 4th grade science class to see if it would improve students' scientific explanations and understanding. A quasi-experimental design, including a non-randomized comparison group and a pre- and post-test design, was adopted for this study. An experimental group of 25 students were taught using the DCI teaching model, while a comparison group received a traditional lecture teaching. A rubric and content analysis was used to assess students' scientific explanations. The independent sample t test was used to measure difference in conceptual understanding between the two groups, before and after instruction. Then, the paired t test analysis was used to understand the promotion of the DCI teaching model. The results showed that students in the experimental group performed better than students in the comparison group, both in scientific concept understanding and explanation. Suggestions for using concept mapping and writing activities (the DCI teaching model) in science classes are provided in this study.

  20. Research traditions and evolutionary explanations in medicine.

    Science.gov (United States)

    Méthot, Pierre-Olivier

    2011-02-01

    In this article, I argue that distinguishing 'evolutionary' from 'Darwinian' medicine will help us assess the variety of roles that evolutionary explanations can play in a number of medical contexts. Because the boundaries of evolutionary and Darwinian medicine overlap to some extent, however, they are best described as distinct 'research traditions' rather than as competing paradigms. But while evolutionary medicine does not stand out as a new scientific field of its own, Darwinian medicine is united by a number of distinctive theoretical and methodological claims. For example, evolutionary medicine and Darwinian medicine can be distinguished with respect to the styles of evolutionary explanations they employ. While the former primarily involves 'forward looking' explanations, the latter depends mostly on 'backward looking' explanations. A forward looking explanation tries to predict the effects of ongoing evolutionary processes on human health and disease in contemporary environments (e.g., hospitals). In contrast, a backward looking explanation typically applies evolutionary principles from the vantage point of humans' distant biological past in order to assess present states of health and disease. Both approaches, however, are concerned with the prevention and control of human diseases. In conclusion, I raise some concerns about the claim that 'nothing in medicine makes sense except in the light of evolution'.

  1. Expectations affect psychological and neurophysiological benefits even after a single bout of exercise.

    Science.gov (United States)

    Mothes, Hendrik; Leukel, Christian; Jo, Han-Gue; Seelig, Harald; Schmidt, Stefan; Fuchs, Reinhard

    2017-04-01

    The study investigated whether typical psychological, physiological, and neurophysiological changes from a single exercise are affected by one's beliefs and expectations. Seventy-six participants were randomly assigned to four groups and saw different multimedia presentations suggesting that the subsequent exercise (moderate 30 min cycling) would result in more or less health benefits (induced expectations). Additionally, we assessed habitual expectations reflecting previous experience and beliefs regarding exercise benefits. Participants with more positive habitual expectations consistently demonstrated both greater psychological benefits (more enjoyment, mood increase, and anxiety reduction) and greater increase of alpha-2 power, assessed with electroencephalography. Manipulating participants' expectations also resulted in largely greater increases of alpha-2 power, but not in more psychological exercise benefits. On the physiological level, participants decreased their blood pressure after exercising, but this was independent of their expectations. These results indicate that habitual expectations in particular affect exercise-induced psychological and neurophysiological changes in a self-fulfilling manner.

  2. Economic explanations for concurrent sourcing

    DEFF Research Database (Denmark)

    Mols, Niels Peter

    2010-01-01

    Concurrent sourcing is a phenomenon where firms simultaneously make and buy the same good, i.e. they simultaneously use the governance modes of market and hierarchy. Though concurrent sourcing seems to be widespread, few studies of sourcing have focused on this phenomenon. This paper reviews...... different economic explanations for why firms use concurrent sourcing. The distinctive features of the explanations are compared, and it is discussed how they may serve as a springboard for research on concurrent sourcing. Managerial implications are also offered....

  3. Customizable cap implants for neurophysiological experimentation.

    Science.gov (United States)

    Blonde, Jackson D; Roussy, Megan; Luna, Rogelio; Mahmoudian, Borna; Gulli, Roberto A; Barker, Kevin C; Lau, Jonathan C; Martinez-Trujillo, Julio C

    2018-04-22

    Several primate neurophysiology laboratories have adopted acrylic-free, custom-fit cranial implants. These implants are often comprised of titanium or plastic polymers, such as polyether ether ketone (PEEK). Titanium is favored for its mechanical strength and osseointegrative properties whereas PEEK is notable for its lightweight, machinability, and MRI compatibility. Recent titanium/PEEK implants have proven to be effective in minimizing infection and implant failure, thereby prolonging experiments and optimizing the scientific contribution of a single primate. We created novel, customizable PEEK 'cap' implants that contour to the primate's skull. The implants were created using MRI and/or CT data, SolidWorks software and CNC-machining. Three rhesus macaques were implanted with a PEEK cap implant. Head fixation and chronic recordings were successfully performed. Improvements in design and surgical technique solved issues of granulation tissue formation and headpost screw breakage. Primate cranial implants have traditionally been fastened to the skull using acrylic and anchor screws. This technique is prone to skin recession, infection, and implant failure. More recent methods have used imaging data to create custom-fit titanium/PEEK implants with radially extending feet or vertical columns. Compared to our design, these implants are more surgically invasive over time, have less force distribution, and/or do not optimize the utilizable surface area of the skull. Our PEEK cap implants served as an effective and affordable means to perform electrophysiological experimentation while reducing surgical invasiveness, providing increased strength, and optimizing useful surface area. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  4. Neurophysiology and itch pathways.

    Science.gov (United States)

    Schmelz, Martin

    2015-01-01

    As we all can easily differentiate the sensations of itch and pain, the most straightforward neurophysiologic concept would consist of two specific pathways that independently encode itch and pain. Indeed, a neuronal pathway for histamine-induced itch in the peripheral and central nervous system has been described in animals and humans, and recently several non-histaminergic pathways for itch have been discovered in rodents that support a dichotomous concept differentiated into a pain and an itch pathway, with both pathways being composed of different "flavors." Numerous markers and mediators have been found that are linked to itch processing pathways. Thus, the delineation of neuronal pathways for itch from pain pathways seemingly proves that all sensory aspects of itch are based on an itch-specific neuronal pathway. However, such a concept is incomplete as itch can also be induced by the activation of the pain pathway in particular when the stimulus is applied in a highly localized spatial pattern. These opposite views reflect the old dispute between specificity and pattern theories of itch. Rather than only being of theoretic interest, this conceptual problem has key implication for the strategy to treat chronic itch as key therapeutic targets would be either itch-specific pathways or unspecific nociceptive pathways.

  5. Evolutionary Explanations of Eating Disorders

    Directory of Open Access Journals (Sweden)

    Igor Kardum

    2008-12-01

    Full Text Available This article reviews several most important evolutionary mechanisms that underlie eating disorders. The first part clarifies evolutionary foundations of mental disorders and various mechanisms leading to their development. In the second part selective pressures and evolved adaptations causing contemporary epidemic of obesity as well as differences in dietary regimes and life-style between modern humans and their ancestors are described. Concerning eating disorders, a number of current evolutionary explanations of anorexia nervosa are presented together with their main weaknesses. Evolutionary explanations of eating disorders based on the reproductive suppression hypothesis and its variants derived from kin selection theory and the model of parental manipulation were elaborated. The sexual competition hypothesis of eating disorder, adapted to flee famine hypothesis as well as explanation based on the concept of social attention holding power and the need to belonging were also explained. The importance of evolutionary theory in modern conceptualization and research of eating disorders is emphasized.

  6. The status of functional explanation in psychology: reduction and mechanistic explanation

    NARCIS (Netherlands)

    Gervais, H.; Looren De Jong, H.

    2013-01-01

    The validity of functional explanations as they are commonly used in psychology has recently come under attack. Kim's supervenience argument purports to prove that higher-level generalizations have no causal powers of their own, and hence are explanatorily irrelevant. In a nutshell, the

  7. A Study of the Effectiveness of Sensory Integration Therapy on Neuro-Physiological Development

    Science.gov (United States)

    Reynolds, Christopher; Reynolds, Kathleen Sheena

    2010-01-01

    Background: Sensory integration theory proposes that because there is plasticity within the central nervous system (the brain is moldable) and because the brain consists of systems that are hierarchically organised, it is possible to stimulate and improve neuro-physiological processing and integration and thereby increase learning capacity.…

  8. Theoretical vocabularies and styles of explanation of robot behaviours in children

    Directory of Open Access Journals (Sweden)

    Datteri Edoardo

    2017-06-01

    Full Text Available How do children describe and explain the behaviour of robotic systems? In this paper, some distinctions between different types of explanations, drawing from the philosophy of science literature, are proposed and exemplified by reference to an activity in which primary school children are asked to describe and explain the behaviour of a pre-programmed Braitenberg-like vehicle. The proposed distinctions are also discussed against other studies drawn from the related scientific literature. A qualitative study has provided insights to further refine the analysis described here, through the introduction of other sub-categories of explanation of robotic behaviours.

  9. Turing patterns and biological explanation

    DEFF Research Database (Denmark)

    Serban, Maria

    2017-01-01

    , promoting theory exploration, and acting as constitutive parts of empirically adequate explanations of naturally occurring phenomena, such as biological pattern formation. Focusing on the roles that minimal model explanations play in science motivates the adoption of a broader diachronic view of scientific......Turing patterns are a class of minimal mathematical models that have been used to discover and conceptualize certain abstract features of early biological development. This paper examines a range of these minimal models in order to articulate and elaborate a philosophical analysis...

  10. Music Evolution in the Laboratory: Cultural Transmission Meets Neurophysiology

    Directory of Open Access Journals (Sweden)

    Massimo Lumaca

    2018-04-01

    Full Text Available In recent years, there has been renewed interest in the biological and cultural evolution of music, and specifically in the role played by perceptual and cognitive factors in shaping core features of musical systems, such as melody, harmony, and rhythm. One proposal originates in the language sciences. It holds that aspects of musical systems evolve by adapting gradually, in the course of successive generations, to the structural and functional characteristics of the sensory and memory systems of learners and “users” of music. This hypothesis has found initial support in laboratory experiments on music transmission. In this article, we first review some of the most important theoretical and empirical contributions to the field of music evolution. Next, we identify a major current limitation of these studies, i.e., the lack of direct neural support for the hypothesis of cognitive adaptation. Finally, we discuss a recent experiment in which this issue was addressed by using event-related potentials (ERPs. We suggest that the introduction of neurophysiology in cultural transmission research may provide novel insights on the micro-evolutionary origins of forms of variation observed in cultural systems.

  11. Music Evolution in the Laboratory: Cultural Transmission Meets Neurophysiology.

    Science.gov (United States)

    Lumaca, Massimo; Ravignani, Andrea; Baggio, Giosuè

    2018-01-01

    In recent years, there has been renewed interest in the biological and cultural evolution of music, and specifically in the role played by perceptual and cognitive factors in shaping core features of musical systems, such as melody, harmony, and rhythm. One proposal originates in the language sciences. It holds that aspects of musical systems evolve by adapting gradually, in the course of successive generations, to the structural and functional characteristics of the sensory and memory systems of learners and "users" of music. This hypothesis has found initial support in laboratory experiments on music transmission. In this article, we first review some of the most important theoretical and empirical contributions to the field of music evolution. Next, we identify a major current limitation of these studies, i.e., the lack of direct neural support for the hypothesis of cognitive adaptation. Finally, we discuss a recent experiment in which this issue was addressed by using event-related potentials (ERPs). We suggest that the introduction of neurophysiology in cultural transmission research may provide novel insights on the micro-evolutionary origins of forms of variation observed in cultural systems.

  12. Maternal Behavior Predicts Infant Neurophysiological and Behavioral Attention Processes in the First Year

    Science.gov (United States)

    Swingler, Margaret M.; Perry, Nicole B.; Calkins, Susan D.; Bell, Martha Ann

    2017-01-01

    We apply a biopsychosocial conceptualization to attention development in the 1st year and examine the role of neurophysiological and social processes on the development of early attention processes. We tested whether maternal behavior measured during 2 mother-child interaction tasks when infants (N = 388) were 5 months predicted infant medial…

  13. How the nerves reached the muscle: Bernard Katz, Stephen W. Kuffler, and John C. Eccles-Certain implications of exile for the development of twentieth-century neurophysiology.

    Science.gov (United States)

    Stahnisch, Frank W

    2017-01-01

    This article explores the work by Bernard Katz (1911-2003), Stephen W. Kuffler (1913-1980), and John C. Eccles (1903-1997) on the nerve-muscle junction as a milestone in twentieth-century neurophysiology with wider scientific implications. The historical question is approached from two perspectives: (a) an investigation of twentieth-century solutions to a longer physiological dispute and (b) an examination of a new kind of laboratory and academic cooperation. From this vantage point, the work pursued in Sydney by Sir John Carew Eccles' team on the neuromuscular junction is particularly valuable, since it contributed a central functional element to modern physiological understanding regarding the function and structure of the human and animal nervous system. The reflex model of neuromuscular action had already been advanced by neuroanatomists such as Georg Prochaska (1749-1820) in Bohemia since the eighteenth century. It became a major component of neurophysiological theories during the nineteenth century, based on the law associated with the names of François Magendie (1783-1855) in France and Charles Bell (1774-1842) in Britain regarding the functional differences of the sensory and motor spinal nerves. Yet, it was not until the beginning of the twentieth century that both the histological and the neurophysiological understanding of the nerve-muscle connection became entirely understood and the chemical versus electrical transmission further elicited as the mechanisms of inhibition. John C. Eccles, Bernard Katz, and Stephen W. Kuffler helped to provide some of the missing links for modern neurophysiology. The current article explores several of their scientific contributions and investigates how the context of forced migration contributed to these interactions in contingently new ways.

  14. Leg Regrowth in Blaberus discoidalis (Discoid Cockroach following Limb Autotomy versus Limb Severance and Relevance to Neurophysiology Experiments.

    Directory of Open Access Journals (Sweden)

    Timothy C Marzullo

    Full Text Available Many insects can regenerate limbs, but less is known about the regrowth process with regard to limb injury type. As part of our neurophysiology education experiments involving the removal of a cockroach leg, 1 the ability of Blaberus discoidalis cockroaches to regenerate a metathoracic leg was examined following autotomy at the femur/trochanter joint versus severance via a transverse coxa-cut, and 2 the neurophysiology of the detached legs with regard to leg removal type was studied by measuring spike firing rate and microstimulation movement thresholds.First appearance of leg regrowth was after 5 weeks in the autotomy group and 12 weeks in the coxa-cut group. Moreover, regenerated legs in the autotomy group were 72% of full size on first appearance, significantly larger (p<0.05 than coxa-cut legs (29% of full size at first appearance. Regenerated legs in both groups grew in size with each subsequent molt; the autotomy-removed legs grew to full size within 18 weeks, whereas coxa-cut legs took longer than 28 weeks to regrow. Removal of the metathoracic leg in both conditions did not have an effect on mortality compared to matched controls with unmolested legs.Autotomy-removed legs had lower spontaneous firing rates, similar marked increased firing rates upon tactile manipulation of tibial barbs, and a 10% higher electrical microstimulation threshold for movement.It is recommended that neurophysiology experiments on cockroach legs remove the limb at autotomy joints instead of coxa cuts, as the leg regenerates significantly faster when autotomized and does not detract from the neurophysiology educational content.

  15. Explanation and Categorization: How "Why?" Informs "What?"

    Science.gov (United States)

    Lombrozo, Tania

    2009-01-01

    Recent theoretical and empirical work suggests that explanation and categorization are intimately related. This paper explores the hypothesis that explanations can help structure conceptual representations, and thereby influence the relative importance of features in categorization decisions. In particular, features may be differentially important…

  16. Neurophysiological detection of impending spinal cord injury during scoliosis surgery.

    Science.gov (United States)

    Schwartz, Daniel M; Auerbach, Joshua D; Dormans, John P; Flynn, John; Drummond, Denis S; Bowe, J Andrew; Laufer, Samuel; Shah, Suken A; Bowen, J Richard; Pizzutillo, Peter D; Jones, Kristofer J; Drummond, Denis S

    2007-11-01

    Despite the many reports attesting to the efficacy of intraoperative somatosensory evoked potential monitoring in reducing the prevalence of iatrogenic spinal cord injury during corrective scoliosis surgery, these afferent neurophysiological signals can provide only indirect evidence of injury to the motor tracts since they monitor posterior column function. Early reports on the use of transcranial electric motor evoked potentials to monitor the corticospinal motor tracts directly suggested that the method holds great promise for improving detection of emerging spinal cord injury. We sought to compare the efficacy of these two methods of monitoring to detect impending iatrogenic neural injury during scoliosis surgery. We reviewed the intraoperative neurophysiological monitoring records of 1121 consecutive patients (834 female and 287 male) with adolescent idiopathic scoliosis (mean age, 13.9 years) treated between 2000 and 2004 at four pediatric spine centers. The same group of experienced surgical neurophysiologists monitored spinal cord function in all patients with use of a standardized multimodality technique with the patient under total intravenous anesthesia. A relevant neurophysiological change (an alert) was defined as a reduction in amplitude (unilateral or bilateral) of at least 50% for somatosensory evoked potentials and at least 65% for transcranial electric motor evoked potentials compared with baseline. Thirty-eight (3.4%) of the 1121 patients had recordings that met the criteria for a relevant signal change (i.e., an alert). Of those thirty-eight patients, seventeen showed suppression of the amplitude of transcranial electric motor evoked potentials in excess of 65% without any evidence of changes in somatosensory evoked potentials. In nine of the thirty-eight patients, the signal change was related to hypotension and was corrected with augmentation of the blood pressure. The remaining twenty-nine patients had an alert that was related directly to a

  17. Generating Explanations for Internet-based Business Games

    Directory of Open Access Journals (Sweden)

    Martin Fischer

    2007-06-01

    Full Text Available It is widely established debriefing in business games is important and influences the students' learning performance. Most games only support game statistics instead of explaining solution paths. We suggest the automatic generation of explanations for internet-mediated business games to improve the debriefing quality. As a proof of concept we developed a prototype of an internet-based auction game embedding an open simulation model and an automatic explanation component helping students and teachers to analyse the decision making process. This paper describes the usefulness of automated explanations and the underlying generic software architecture.

  18. Neurophysiological correlates of attention behavior in early infancy: Implications for emotion regulation during early childhood

    Science.gov (United States)

    Perry, Nicole B.; Swingler, Margaret M.; Calkins, Susan D.; Bell, Martha Ann

    2015-01-01

    Current theoretical conceptualizations of regulatory development suggest that attention processes and emotion regulation processes share common neurophysiological underpinnings and behavioral antecedents such that emotion regulation abilities may build upon early attentional skills. To further elucidate this proposed relationship, we tested whether early neurophysiological processes measured during an attention task in infancy predicted in-task attention behavior, and whether infant's attention behavior was subsequently associated with their ability to regulate emotion in early childhood (N=388). Results indicated that, greater EEG power change (from baseline to task) at medial frontal locations (F3 and F4) during an attention task at 10 months were associated with concurrent observed behavioral attention. Specifically, greater change in EEG power at the right frontal location (F4) was associated with more attention, and greater EEG power at the left frontal location (F3) was associated with less attention, indicating a potential right hemisphere specialization for attention processes already present in the first year of life. In addition, after controlling for 5-month attention behavior, increased behavioral attention at 10-months was negatively associated with children's observed frustration to emotional challenge at age 3. Finally, the indirect effects from 10-month EEG power change at F3 and F4 to 3-year emotion regulation via infants' 10-month behavioral attention were significant, suggesting that infant's attention behavior is one mechanism through which early neurophysiological activity is related to emotion regulation abilities in childhood. PMID:26381926

  19. Neurophysiological determinants of tic severity in children with chronic motor tic disorder.

    Science.gov (United States)

    Siniatchkin, Michael; Kuppe, Andrea

    2011-06-01

    Tics wax and wane in severity. Although the understanding of the natural course of symptoms in tic disorder (TD) is important for planning and assessing therapeutic interventions, neurophysiological mechanisms and predictors of tic exacerbation and remission have not been sufficiently investigated. In each of seven children suffering from TD, contingent negative variation (CNV) was recorded on 10 occasions over a period of 2 months. CNV parameters of children with TD were compared with CNV data of healthy, age-matched children. During the entire time of observation, tic severity was assessed by parents and the investigator using a scale developed from the Yale Global Tic Severity Scale. Moreover, tic severity was also evaluated using video assessments. Patients with TD were characterized by significantly lower amplitude of the total CNV and more pronounced habituation of the early CNV component as compared to healthy children. Correlation analysis between tic severity and CNV parameters demonstrated that the more severe the tics were, the lower the amplitude of the total CNV. Since CNV amplitude represents processes of resource mobilization and control over neuronal excitability, tic severity may result from less ability to control neurophysiological functions in patients with TD.

  20. Neurophysiology in preschool improves behavioral prediction of reading ability throughout primary school.

    Science.gov (United States)

    Maurer, Urs; Bucher, Kerstin; Brem, Silvia; Benz, Rosmarie; Kranz, Felicitas; Schulz, Enrico; van der Mark, Sanne; Steinhausen, Hans-Christoph; Brandeis, Daniel

    2009-08-15

    More struggling readers could profit from additional help at the beginning of reading acquisition if dyslexia prediction were more successful. Currently, prediction is based only on behavioral assessment of early phonological processing deficits associated with dyslexia, but it might be improved by adding brain-based measures. In a 5-year longitudinal study of children with (n = 21) and without (n = 23) familial risk for dyslexia, we tested whether neurophysiological measures of automatic phoneme and tone deviance processing obtained in kindergarten would improve prediction of reading over behavioral measures alone. Together, neurophysiological and behavioral measures obtained in kindergarten significantly predicted reading in school. Particularly the late mismatch negativity measure that indicated hemispheric lateralization of automatic phoneme processing improved prediction of reading ability over behavioral measures. It was also the only significant predictor for long-term reading success in fifth grade. Importantly, this result also held for the subgroup of children at familial risk. The results demonstrate that brain-based measures of processing deficits associated with dyslexia improve prediction of reading and thus may be further evaluated to complement clinical practice of dyslexia prediction, especially in targeted populations, such as children with a familial risk.

  1. Cannabinoid-induced effects on the nociceptive system: a neurophysiological study in patients with secondary progressive multiple sclerosis.

    Science.gov (United States)

    Conte, Antonella; Bettolo, Chiara Marini; Onesti, Emanuela; Frasca, Vittorio; Iacovelli, Elisa; Gilio, Francesca; Giacomelli, Elena; Gabriele, Maria; Aragona, Massimiliano; Tomassini, Valentina; Pantano, Patrizia; Pozzilli, Carlo; Inghilleri, Maurizio

    2009-05-01

    Although clinical studies show that cannabinoids improve central pain in patients with multiple sclerosis (MS) neurophysiological studies are lacking to investigate whether they also suppress these patients' electrophysiological responses to noxious stimulation. The flexion reflex (FR) in humans is a widely used technique for assessing the pain threshold and for studying spinal and supraspinal pain pathways and the neurotransmitter system involved in pain control. In a randomized, double-blind, placebo-controlled, cross-over study we investigated cannabinoid-induced changes in RIII reflex variables (threshold, latency and area) in a group of 18 patients with secondary progressive MS. To investigate whether cannabinoids act indirectly on the nociceptive reflex by modulating lower motoneuron excitability we also evaluated the H-reflex size after tibial nerve stimulation and calculated the H wave/M wave (H/M) ratio. Of the 18 patients recruited and randomized 17 completed the study. After patients used a commercial delta-9-tetrahydrocannabinol (THC) and cannabidiol mixture as an oromucosal spray the RIII reflex threshold increased and RIII reflex area decreased. The visual analogue scale score for pain also decreased, though not significantly. Conversely, the H/M ratio measured before patients received cannabinoids remained unchanged after therapy. In conclusion, the cannabinoid-induced changes in the RIII reflex threshold and area in patients with MS provide objective neurophysiological evidence that cannabinoids modulate the nociceptive system in patients with MS.

  2. Intra-operative neurophysiological mapping and monitoring during brain tumour surgery in children: an update.

    Science.gov (United States)

    Coppola, Angela; Tramontano, Vincenzo; Basaldella, Federica; Arcaro, Chiara; Squintani, Giovanna; Sala, Francesco

    2016-10-01

    Over the past decade, the reluctance to operate in eloquent brain areas has been reconsidered in the light of the advent of new peri-operative functional neuroimaging techniques and new evidence from neuro-oncology. To maximise tumour resection while minimising morbidity should be the goal of brain surgery in children as much as it is in adults, and preservation of brain functions is critical in the light of the increased survival and the expectations in terms of quality of life. Intra-operative neurophysiology is the gold standard to localise and preserve brain functions during surgery and is increasingly used in paediatric neurosurgery. Yet, the developing nervous system has peculiar characteristics in terms of anatomical and physiological maturation, and some technical aspects need to be tailored for its use in children, especially in infants. This paper will review the most recent advances in the field of intra-operative neurophysiology (ION) techniques during brain surgery, focussing on those aspects that are relevant to the paediatric neurosurgery practice.

  3. Nursing Teaching Strategies by Encouraging Students’ Questioning, Argumentation and Explanation

    Directory of Open Access Journals (Sweden)

    Dayse Neri de Souza

    2014-12-01

    Full Text Available Nursing students need to develop competences in the field of explanation, argumentation and questioning as they are pivotal to foster a relationship with their patients and achieve a greater humanisation of care. The objective of this paper is to analyse the perception of 1st-year nursing students with regard to the humanisation of care provided to patients by encouraging them to discuss real-life episodes. The study is qualitative and content analysis used the students’ questions, explanations and argumentation as core discourses. Among other conclusions, results point towards the importance of promoting activities that encourage the different nursing students’ discourses and the ability to understand the humanisation and dehumanisation patterns arising from the real-life episodes used as case study.

  4. Action Priority: Early Neurophysiological Interaction of Conceptual and Motor Representations

    Science.gov (United States)

    Koester, Dirk; Schack, Thomas

    2016-01-01

    Handling our everyday life, we often react manually to verbal requests or instruction, but the functional interrelations of motor control and language are not fully understood yet, especially their neurophysiological basis. Here, we investigated whether specific motor representations for grip types interact neurophysiologically with conceptual information, that is, when reading nouns. Participants performed lexical decisions and, for words, executed a grasp-and-lift task on objects of different sizes involving precision or power grips while the electroencephalogram was recorded. Nouns could denote objects that require either a precision or a power grip and could, thus, be (in)congruent with the performed grasp. In a control block, participants pointed at the objects instead of grasping them. The main result revealed an event-related potential (ERP) interaction of grip type and conceptual information which was not present for pointing. Incongruent compared to congruent conditions elicited an increased positivity (100–200 ms after noun onset). Grip type effects were obtained in response-locked analyses of the grasping ERPs (100–300 ms at left anterior electrodes). These findings attest that grip type and conceptual information are functionally related when planning a grasping action but such an interaction could not be detected for pointing. Generally, the results suggest that control of behaviour can be modulated by task demands; conceptual noun information (i.e., associated action knowledge) may gain processing priority if the task requires a complex motor response. PMID:27973539

  5. 5 CFR 1201.101 - Explanation and definitions.

    Science.gov (United States)

    2010-01-01

    ... definitions. (a) Explanation. An ex parte communication is an oral or written communication between a decision... outcome of a proceeding before the Board. (2) Decision-making official means any judge, officer or other... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Explanation and definitions. 1201.101...

  6. PLDAPS: A Hardware Architecture and Software Toolbox for Neurophysiology Requiring Complex Visual Stimuli and Online Behavioral Control.

    Science.gov (United States)

    Eastman, Kyler M; Huk, Alexander C

    2012-01-01

    Neurophysiological studies in awake, behaving primates (both human and non-human) have focused with increasing scrutiny on the temporal relationship between neural signals and behaviors. Consequently, laboratories are often faced with the problem of developing experimental equipment that can support data recording with high temporal precision and also be flexible enough to accommodate a wide variety of experimental paradigms. To this end, we have developed a MATLAB toolbox that integrates several modern pieces of equipment, but still grants experimenters the flexibility of a high-level programming language. Our toolbox takes advantage of three popular and powerful technologies: the Plexon apparatus for neurophysiological recordings (Plexon, Inc., Dallas, TX, USA), a Datapixx peripheral (Vpixx Technologies, Saint-Bruno, QC, Canada) for control of analog, digital, and video input-output signals, and the Psychtoolbox MATLAB toolbox for stimulus generation (Brainard, 1997; Pelli, 1997; Kleiner et al., 2007). The PLDAPS ("Platypus") system is designed to support the study of the visual systems of awake, behaving primates during multi-electrode neurophysiological recordings, but can be easily applied to other related domains. Despite its wide range of capabilities and support for cutting-edge video displays and neural recording systems, the PLDAPS system is simple enough for someone with basic MATLAB programming skills to design their own experiments.

  7. Neurophysiological and Behavioral Differences between Older and Younger Adults When Processing Violations of Tonal Structure in Music

    Science.gov (United States)

    Lagrois, Marie-Élaine; Peretz, Isabelle; Zendel, Benjamin Rich

    2018-01-01

    Aging is associated with decline in both cognitive and auditory abilities. However, evidence suggests that music perception is relatively spared, despite relying on auditory and cognitive abilities that tend to decline with age. It is therefore likely that older adults engage compensatory mechanisms which should be evident in the underlying functional neurophysiology related to processing music. In other words, the perception of musical structure would be similar or enhanced in older compared to younger adults, while the underlying functional neurophysiology would be different. The present study aimed to compare the electrophysiological brain responses of younger and older adults to melodic incongruities during a passive and active listening task. Older and younger adults had a similar ability to detect an out-of-tune incongruity (i.e., non-chromatic), while the amplitudes of the ERAN and P600 were reduced in older adults compared to younger adults. On the other hand, out-of-key incongruities (i.e., non-diatonic), were better detected by older adults compared to younger adults, while the ERAN and P600 were comparable between the two age groups. This pattern of results indicates that perception of tonal structure is preserved in older adults, despite age-related neurophysiological changes in how melodic violations are processed. PMID:29487498

  8. Neurophysiological and Behavioral Differences between Older and Younger Adults When Processing Violations of Tonal Structure in Music

    Directory of Open Access Journals (Sweden)

    Marie-Élaine Lagrois

    2018-02-01

    Full Text Available Aging is associated with decline in both cognitive and auditory abilities. However, evidence suggests that music perception is relatively spared, despite relying on auditory and cognitive abilities that tend to decline with age. It is therefore likely that older adults engage compensatory mechanisms which should be evident in the underlying functional neurophysiology related to processing music. In other words, the perception of musical structure would be similar or enhanced in older compared to younger adults, while the underlying functional neurophysiology would be different. The present study aimed to compare the electrophysiological brain responses of younger and older adults to melodic incongruities during a passive and active listening task. Older and younger adults had a similar ability to detect an out-of-tune incongruity (i.e., non-chromatic, while the amplitudes of the ERAN and P600 were reduced in older adults compared to younger adults. On the other hand, out-of-key incongruities (i.e., non-diatonic, were better detected by older adults compared to younger adults, while the ERAN and P600 were comparable between the two age groups. This pattern of results indicates that perception of tonal structure is preserved in older adults, despite age-related neurophysiological changes in how melodic violations are processed.

  9. Data for the elaboration of the CIPROS checklist with items for a patient registry software system: Examples and explanations

    Directory of Open Access Journals (Sweden)

    Doris Lindoerfer

    2017-10-01

    The data presented per checklist item provide the relevant textual information (examples and a first qualitative summary (explanation. The examples and explanations provide the background information on CIPROS. They elucidate how to implement the checklist items in other projects. The literature list and the selected texts serve as a reference for scientists and system developers.

  10. A Bayesian explanation of the "Uncanny Valley" effect and related psychological phenomena

    Science.gov (United States)

    Moore, Roger K.

    2012-11-01

    There are a number of psychological phenomena in which dramatic emotional responses are evoked by seemingly innocuous perceptual stimuli. A well known example is the `uncanny valley' effect whereby a near human-looking artifact can trigger feelings of eeriness and repulsion. Although such phenomena are reasonably well documented, there is no quantitative explanation for the findings and no mathematical model that is capable of predicting such behavior. Here I show (using a Bayesian model of categorical perception) that differential perceptual distortion arising from stimuli containing conflicting cues can give rise to a perceptual tension at category boundaries that could account for these phenomena. The model is not only the first quantitative explanation of the uncanny valley effect, but it may also provide a mathematical explanation for a range of social situations in which conflicting cues give rise to negative, fearful or even violent reactions.

  11. Current and novel insights into the neurophysiology of migraine and its implications for therapeutics.

    Science.gov (United States)

    Akerman, Simon; Romero-Reyes, Marcela; Holland, Philip R

    2017-04-01

    Migraine headache and its associated symptoms have plagued humans for two millennia. It is manifest throughout the world, and affects more than 1/6 of the global population. It is the most common brain disorder, and is characterized by moderate to severe unilateral headache that is accompanied by vomiting, nausea, photophobia, phonophobia, and other hypersensitive symptoms of the senses. While there is still a clear lack of understanding of its neurophysiology, it is beginning to be understood, and it seems to suggest migraine is a disorder of brain sensory processing, characterized by a generalized neuronal hyperexcitability. The complex symptomatology of migraine indicates that multiple neuronal systems are involved, including brainstem and diencephalic systems, which function abnormally, resulting in premonitory symptoms, ultimately evolving to affect the dural trigeminovascular system, and the pain phase of migraine. The migraineur also seems to be particularly sensitive to fluctuations in homeostasis, such as sleep, feeding and stress, reflecting the abnormality of functioning in these brainstem and diencephalic systems. Implications for therapeutic development have grown out of our understanding of migraine neurophysiology, leading to major drug classes, such as triptans, calcitonin gene-related peptide receptor antagonists, and 5-HT 1F receptor agonists, as well as neuromodulatory approaches, with the promise of more to come. The present review will discuss the current understanding of the neurophysiology of migraine, particularly migraine headache, and novel insights into the complex neural networks responsible for associated neurological symptoms, and how interaction of these networks with migraine pain pathways has implications for the development of novel therapeutics. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. SPIRIT 2013 explanation and elaboration: guidance for protocols of clinical trials.

    Science.gov (United States)

    Chan, An-Wen; Tetzlaff, Jennifer M; Gøtzsche, Peter C; Altman, Douglas G; Mann, Howard; Berlin, Jesse A; Dickersin, Kay; Hróbjartsson, Asbjørn; Schulz, Kenneth F; Parulekar, Wendy R; Krleza-Jeric, Karmela; Laupacis, Andreas; Moher, David

    2013-01-08

    High quality protocols facilitate proper conduct, reporting, and external review of clinical trials. However, the completeness of trial protocols is often inadequate. To help improve the content and quality of protocols, an international group of stakeholders developed the SPIRIT 2013 Statement (Standard Protocol Items: Recommendations for Interventional Trials). The SPIRIT Statement provides guidance in the form of a checklist of recommended items to include in a clinical trial protocol. This SPIRIT 2013 Explanation and Elaboration paper provides important information to promote full understanding of the checklist recommendations. For each checklist item, we provide a rationale and detailed description; a model example from an actual protocol; and relevant references supporting its importance. We strongly recommend that this explanatory paper be used in conjunction with the SPIRIT Statement. A website of resources is also available (www.spirit-statement.org). The SPIRIT 2013 Explanation and Elaboration paper, together with the Statement, should help with the drafting of trial protocols. Complete documentation of key trial elements can facilitate transparency and protocol review for the benefit of all stakeholders.

  13. Dreaming and the brain: from phenomenology to neurophysiology.

    Science.gov (United States)

    Nir, Yuval; Tononi, Giulio

    2010-02-01

    Dreams are a remarkable experiment in psychology and neuroscience, conducted every night in every sleeping person. They show that the human brain, disconnected from the environment, can generate an entire world of conscious experiences by itself. Content analysis and developmental studies have promoted understanding of dream phenomenology. In parallel, brain lesion studies, functional imaging and neurophysiology have advanced current knowledge of the neural basis of dreaming. It is now possible to start integrating these two strands of research to address fundamental questions that dreams pose for cognitive neuroscience: how conscious experiences in sleep relate to underlying brain activity; why the dreamer is largely disconnected from the environment; and whether dreaming is more closely related to mental imagery or to perception. Published by Elsevier Ltd.

  14. Energy drinks and the neurophysiological impact of caffeine.

    Science.gov (United States)

    Persad, Leeana Aarthi Bagwath

    2011-01-01

    Caffeine is the most widely used psychoactive stimulant with prevalent use across all age groups. It is a naturally occurring substance found in the coffee bean, tea leaf, the kola nut, cocoa bean. Recently there has been an increase in energy drink consumption leading to caffeine abuse, with aggressive marketing and poor awareness on the consequences of high caffeine use. With caffeine consumption being so common, it is vital to know the impact caffeine has on the body, as its effects can influence cardio-respiratory, endocrine, and perhaps most importantly neurological systems. Detrimental effects have being described especially since an over consumption of caffeine has being noted. This review focuses on the neurophysiological impact of caffeine and its biochemical pathways in the human body.

  15. Dreaming and the brain: from phenomenology to neurophysiology

    Science.gov (United States)

    Nir, Yuval; Tononi, Giulio

    2009-01-01

    Dreams are a most remarkable experiment in psychology and neuroscience, conducted every night in every sleeping person. They show that our brain, disconnected from the environment, can generate by itself an entire world of conscious experiences. Content analysis and developmental studies have furthered our understanding of dream phenomenology. In parallel, brain lesion studies, functional imaging, and neurophysiology have advanced our knowledge of the neural basis of dreaming. It is now possible to start integrating these two strands of research in order to address some fundamental questions that dreams pose for cognitive neuroscience: how conscious experiences in sleep relate to underlying brain activity; why the dreamer is largely disconnected from the environment; and whether dreaming is more closely related to mental imagery or to perception. PMID:20079677

  16. Energy drinks and the neurophysiological impacts of caffeine

    Directory of Open Access Journals (Sweden)

    Leeana eBagwath Persad

    2011-10-01

    Full Text Available Caffeine is the most widely used psychoactive stimulant with prevalent use across all age groups. It is a naturally occurring substance found in the coffee bean, tea leaf, the kola nut, cocoa bean. Recently there has been an increase in energy drink consumption leading to caffeine abuse, with aggressive marketing and poor awareness on the consequences of high caffeine use. With caffeine consumption being so common, it is vital to know the impact caffeine has on the body, as its effects can influence cardio-respiratory, endocrine and perhaps most importantly neurological systems. Detrimental effects have being described especially since an over consumption of caffeine has being noted. This review focuses on the neurophysiological impact of caffeine and its biochemical pathways in the human body.

  17. An explanation of the Hiroshima activation dilemma

    International Nuclear Information System (INIS)

    Rhoades, W.A.; Barnes, J.M.; Santoro, R.T.

    1994-01-01

    A 1987 study of the radiation from the World War II nuclear weapons applied state-of-the-art data and computer techniques, providing an important advance in reliability of the results. Still, a disturbing disagreement remained between slow-neutron activation measurements and calculations for the Hiroshima event. Newer data have confirmed the validity of the discrepancy. This work examines various potential explanations. Of those examined, only an enhancement to the weapon neutron leakage spectrum in the vicinity of the 2.3 MeV oxygen cross section window can fit the data accurately

  18. Neurophysiological evidence of impaired self-monitoring in schizotypal personality disorder and its reversal by dopaminergic antagonism

    Directory of Open Access Journals (Sweden)

    Mireia Rabella

    2016-01-01

    Conclusions: These results indicate that SPD individuals show deficits in self-monitoring analogous to those in schizophrenia. These deficits can be evidenced by neurophysiological measures, suggest a dopaminergic imbalance, and can be reverted by dopaminergic antagonists.

  19. Students' reasons for preferring teleological explanations

    Science.gov (United States)

    Trommler, Friederike; Gresch, Helge; Hammann, Marcus

    2018-01-01

    The teleological bias, a major learning obstacle, involves explaining biological phenomena in terms of purposes and goals. To probe the teleological bias, researchers have used acceptance judgement tasks and preference judgement tasks. In the present study, such tasks were used with German high school students (N = 353) for 10 phenomena from human biology, that were explained both teleologically and causally. A sub-sample (n = 26) was interviewed about the reasons for their preferences. The results showed that the students favoured teleological explanations over causal explanations. Although the students explained their preference judgements etiologically (i.e. teleologically and causally), they also referred to a wide range of non-etiological criteria (i.e. familiarity, complexity, relevance and five more criteria). When elaborating on their preference for causal explanations, the students often focused not on the causality of the phenomenon, but on mechanisms whose complexity they found attractive. When explaining their preference for teleological explanations, they often focused not teleologically on purposes and goals, but rather on functions, which they found familiar and relevant. Generally, students' preference judgements rarely allowed for making inferences about causal reasoning and teleological reasoning, an issue that is controversial in the literature. Given that students were largely unaware of causality and teleology, their attention must be directed towards distinguishing between etiological and non-etiological reasoning. Implications for educational practice as well as for future research are discussed.

  20. Reasoning in explanation-based decision making.

    Science.gov (United States)

    Pennington, N; Hastie, R

    1993-01-01

    A general theory of explanation-based decision making is outlined and the multiple roles of inference processes in the theory are indicated. A typology of formal and informal inference forms, originally proposed by Collins (1978a, 1978b), is introduced as an appropriate framework to represent inferences that occur in the overarching explanation-based process. Results from the analysis of verbal reports of decision processes are presented to demonstrate the centrality and systematic character of reasoning in a representative legal decision-making task.

  1. Graphical explanation in an expert system for Space Station Freedom rack integration

    Science.gov (United States)

    Craig, F. G.; Cutts, D. E.; Fennel, T. R.; Purves, B.

    1990-01-01

    The rationale and methodology used to incorporate graphics into explanations provided by an expert system for Space Station Freedom rack integration is examined. The rack integration task is typical of a class of constraint satisfaction problems for large programs where expertise from several areas is required. Graphically oriented approaches are used to explain the conclusions made by the system, the knowledge base content, and even at more abstract levels the control strategies employed by the system. The implemented architecture combines hypermedia and inference engine capabilities. The advantages of this architecture include: closer integration of user interface, explanation system, and knowledge base; the ability to embed links to deeper knowledge underlying the compiled knowledge used in the knowledge base; and allowing for more direct control of explanation depth and duration by the user. The graphical techniques employed range from simple statis presentation of schematics to dynamic creation of a series of pictures presented motion picture style. User models control the type, amount, and order of information presented.

  2. A “Pathology Explanation Clinic (PEC” for Patient-Centered Laboratory Medicine Test Results

    Directory of Open Access Journals (Sweden)

    Blake Gibson MD

    2018-03-01

    Full Text Available This concept paper addresses communication issues arising between physicians and their patients. To facilitate the communication of essential diagnostic pathology information to patients, and address their questions and concerns, we propose that “Pathology Explanation Clinics” be created. The Pathology Explanation Clinics would provide a channel for direct communications between pathologists and patients. Pathologists would receive special training as “Certified Pathologist Navigators” in preparation for this role. The goal of Pathology Explanation Clinics would be to help fill gaps in communication of information contained in laboratory reports to patients, further explain its relevance, and improve patient understanding of the meaning of such information and its impact on their health and health-care choices. Effort would be made to ensure that Certified Pathologist Navigators work within the overall coordination of care by the health-care team.

  3. A new explanation of the extinction paradox

    International Nuclear Information System (INIS)

    Berg, M.J.; Sorensen, C.M.; Chakrabarti, A.

    2011-01-01

    This work presents a new explanation for the extinction paradox and shows that the canonical explanations are incorrect. This paradox refers to the large size limit of a particle's extinction cross section. It is called a paradox because the geometrical optics approximation, which should be valid in this limit, predicts a cross section that is half of the true value. The new explanation is achieved by formulating the scattered wave in terms of an integral over the particle's surface where the seemingly unrelated Ewald-Oseen theorem appears in the formulation. By expressing the cross section in terms of this surface integral, the Ewald-Oseen theorem is analytically connected to the cross section. Several illustrations are used to reveal the significance of this connection: The paradox is seen to be a consequence of the requirement that the incident wave be canceled within the particle by secondary radiation from its own internal field. Following this, the canonical explanations are examined to reveal serious problems. In the process, the same asymptotic extinction behavior is shown to occur for small highly refractive dielectric particles, and thus is not just a large particle size or small wavelength effect as is often stated. The traditional explanations cannot account for this behavior while the new one actually predicts it. All in all, this work constitutes a fundamental reworking of 60 years of accepted understanding for the cause of the asymptotic behavior of the extinction cross section.

  4. Mirror neuron system and observational learning: behavioral and neurophysiological evidence.

    Science.gov (United States)

    Lago-Rodriguez, Angel; Lopez-Alonso, Virginia; Fernández-del-Olmo, Miguel

    2013-07-01

    Three experiments were performed to study observational learning using behavioral, perceptual, and neurophysiological data. Experiment 1 investigated whether observing an execution model, during physical practice of a transitive task that only presented one execution strategy, led to performance improvements compared with physical practice alone. Experiment 2 investigated whether performing an observational learning protocol improves subjects' action perception. In experiment 3 we evaluated whether the type of practice performed determined the activation of the Mirror Neuron System during action observation. Results showed that, compared with physical practice, observing an execution model during a task that only showed one execution strategy does not provide behavioral benefits. However, an observational learning protocol allows subjects to predict more precisely the outcome of the learned task. Finally, intersperse observation of an execution model with physical practice results in changes of primary motor cortex activity during the observation of the motor pattern previously practiced, whereas modulations in the connectivity between primary and non primary motor areas (PMv-M1; PPC-M1) were not affected by the practice protocol performed by the observer. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. An ancient explanation of presbyopia based on binocular vision.

    Science.gov (United States)

    Barbero, Sergio

    2014-06-01

    Presbyopia, understood as the age-related loss of ability to clearly see near objects, was known to ancient Greeks. However, few references to it can be found in ancient manuscripts. A relevant discussion on presbyopia appears in a book called Symposiacs written by Lucius Mestrius Plutarchus around 100 A.C. In this work, Plutarch provided four explanations of presbyopia, associated with different theories of vision. One of the explanations is particularly interesting as it is based on a binocular theory of vision. In this theory, vision is produced when visual rays, emanating from the eyes, form visual cones that impinge on the objects to be seen. Visual rays coming from old people's eyes, it was supposed, are weaker than those from younger people's eyes; so the theory, to be logically coherent, implies that this effect is compensated by the increase in light intensity due to the overlapping, at a certain distance, of the visual cones coming from both eyes. Thus, it benefits the reader to move the reading text further away from the eyes in order to increase the fusion area of both visual cones. The historical hypothesis taking into consideration that the astronomer Hipparchus of Nicaea was the source of Plutarch's explanation of the theory is discussed. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  6. Sex Differences in Neurophysiological Activation Patterns During Phonological Input Processing: An Influencing Factor for Normative Data.

    Science.gov (United States)

    Aerts, Annelies; van Mierlo, Pieter; Hartsuiker, Robert J; Santens, Patrick; De Letter, Miet

    2015-11-01

    In the context of neurophysiological normative data, it has been established that aging has a significant impact on neurophysiological correlates of auditory phonological input processes, such as phoneme discrimination (PD) and word recognition (WR). Besides age, sex is another demographic factor that influences several language processes. We aimed to disentangle whether sex has a similar effect on PD and WR. Event-related potentials (ERPs) were recorded in 20 men and 24 women. During PD, three phonemic contrasts (place and manner of articulation and voicing) were compared using the attentive P300 and pre-attentive Mismatch Negativity. To investigate WR, real words were contrasted with pseudowords in a pre-attentive oddball task. Women demonstrated a larger sensitivity to spectrotemporal differences, as evidenced by larger P300 responses to the place of articulation (PoA) contrast and larger P300 and MMN responses than men in PoA-based PD. Men did not display such sensitivity. Attention played an important role, considering that women needed more attentional resources to differentiate between PoA and the other phonemic contrasts. During WR, pseudowords evoked larger amplitudes already 100 ms post-stimulus independent of sex. However, women had decreased P200 latencies, but longer N400 latencies in response to pseudowords, whereas men showed increased N400 latencies compared to women in response to real words. The current results demonstrate significant sex-related influences on phonological input processes. Therefore, existing neurophysiological normative data for age should be complemented for the factor sex.

  7. An integral investigation into the phenomenology and neurophysiology of Christian Trinity meditation

    Directory of Open Access Journals (Sweden)

    Stephen D. Edwards

    2012-03-01

    Full Text Available This integral investigation explored phenomenological and neurophysiologic, individual and collective dimensions of Christian Trinitarian meditation experiences in a volunteer, convenience sample of 10 practicing Christians, 6 men and 4 women, with a mean age of 48 years and an age range from 21 to 85 years. Participants meditated for a minimum period of 15 minutes, during which neurophysiologic data in the form of electroencephalographic (EEG, electromyographic (EMG, blood volume pulse (BVP and respiratory activity were recorded. A phenomenological analysis indicated that the meditation process generally involved a movement from body to mind to spirit as evident in reports of an increasingly relaxed, contented and focused state of consciousness characterised by Christian Trinitarian imagery, wonder, surrender, peace, bliss, openness and formlessness. The neuropsychological findings indicated significant increases, from baseline to meditation recordings, in the alpha and beta range, accompanied by increasing mean trends in the theta and gamma range, and decreasing mean trends in the delta range, EMG, BVP and respiration. Integrative findings indicated the practical theological value of small doses of Christian Trinity meditation to enhance spiritual life for those forms of waking, thinking, conscious behaviour needed in everyday world involvement and healing. Findings were discussed in relation to further integrative investigations and interventions with practical theological implications.

  8. Reward Prediction Errors in Drug Addiction and Parkinson's Disease: from Neurophysiology to Neuroimaging.

    Science.gov (United States)

    García-García, Isabel; Zeighami, Yashar; Dagher, Alain

    2017-06-01

    Surprises are important sources of learning. Cognitive scientists often refer to surprises as "reward prediction errors," a parameter that captures discrepancies between expectations and actual outcomes. Here, we integrate neurophysiological and functional magnetic resonance imaging (fMRI) results addressing the processing of reward prediction errors and how they might be altered in drug addiction and Parkinson's disease. By increasing phasic dopamine responses, drugs might accentuate prediction error signals, causing increases in fMRI activity in mesolimbic areas in response to drugs. Chronic substance dependence, by contrast, has been linked with compromised dopaminergic function, which might be associated with blunted fMRI responses to pleasant non-drug stimuli in mesocorticolimbic areas. In Parkinson's disease, dopamine replacement therapies seem to induce impairments in learning from negative outcomes. The present review provides a holistic overview of reward prediction errors across different pathologies and might inform future clinical strategies targeting impulsive/compulsive disorders.

  9. Advancing the Neurophysiological Understanding of Delirium.

    Science.gov (United States)

    Shafi, Mouhsin M; Santarnecchi, Emiliano; Fong, Tamara G; Jones, Richard N; Marcantonio, Edward R; Pascual-Leone, Alvaro; Inouye, Sharon K

    2017-06-01

    Delirium is a common problem associated with substantial morbidity and increased mortality. However, the brain dysfunction that leads some individuals to develop delirium in response to stressors is unclear. In this article, we briefly review the neurophysiologic literature characterizing the changes in brain function that occur in delirium, and in other cognitive disorders such as Alzheimer's disease. Based on this literature, we propose a conceptual model for delirium. We propose that delirium results from a breakdown of brain function in individuals with impairments in brain connectivity and brain plasticity exposed to a stressor. The validity of this conceptual model can be tested using Transcranial Magnetic Stimulation in combination with Electroencephalography, and, if accurate, could lead to the development of biomarkers for delirium risk in individual patients. This model could also be used to guide interventions to decrease the risk of cerebral dysfunction in patients preoperatively, and facilitate recovery in patients during or after an episode of delirium. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

  10. Social Consumer Neuroscience: Neurophysiological Measures of Advertising Effectiveness in a Social Context

    OpenAIRE

    Pozharliev, Rumen; Verbeke, Willem; Bagozzi, Richard

    2017-01-01

    textabstractThe application of neurophysiological methods to study the effects of advertising on consumer purchase behavior has seen an enormous growth in recent years. However, little is known about the role social settings have on shaping the human brain during the processing of advertising stimuli. To address this issue, we first review previous key findings of neuroscience research on advertising effectiveness. Next, we discuss traditional advertising research into the effects social cont...

  11. The neurophysiology of language processing shapes the evolution of grammar: evidence from case marking.

    Science.gov (United States)

    Bickel, Balthasar; Witzlack-Makarevich, Alena; Choudhary, Kamal K; Schlesewsky, Matthias; Bornkessel-Schlesewsky, Ina

    2015-01-01

    Do principles of language processing in the brain affect the way grammar evolves over time or is language change just a matter of socio-historical contingency? While the balance of evidence has been ambiguous and controversial, we identify here a neurophysiological constraint on the processing of language that has a systematic effect on the evolution of how noun phrases are marked by case (i.e. by such contrasts as between the English base form she and the object form her). In neurophysiological experiments across diverse languages we found that during processing, participants initially interpret the first base-form noun phrase they hear (e.g. she…) as an agent (which would fit a continuation like … greeted him), even when the sentence later requires the interpretation of a patient role (as in … was greeted). We show that this processing principle is also operative in Hindi, a language where initial base-form noun phrases most commonly denote patients because many agents receive a special case marker ("ergative") and are often left out in discourse. This finding suggests that the principle is species-wide and independent of the structural affordances of specific languages. As such, the principle favors the development and maintenance of case-marking systems that equate base-form cases with agents rather than with patients. We confirm this evolutionary bias by statistical analyses of phylogenetic signals in over 600 languages worldwide, controlling for confounding effects from language contact. Our findings suggest that at least one core property of grammar systematically adapts in its evolution to the neurophysiological conditions of the brain, independently of socio-historical factors. This opens up new avenues for understanding how specific properties of grammar have developed in tight interaction with the biological evolution of our species.

  12. Tactile and non-tactile sensory paradigms for fMRI and neurophysiologic studies in rodents.

    Science.gov (United States)

    Sanganahalli, Basavaraju G; Bailey, Christopher J; Herman, Peter; Hyder, Fahmeed

    2009-01-01

    Functional magnetic resonance imaging (fMRI) has become a popular functional imaging tool for human studies. Future diagnostic use of fMRI depends, however, on a suitable neurophysiologic interpretation of the blood oxygenation level dependent (BOLD) signal change. This particular goal is best achieved in animal models primarily due to the invasive nature of other methods used and/or pharmacological agents applied to probe different nuances of neuronal (and glial) activity coupled to the BOLD signal change. In the last decade, we have directed our efforts towards the development of stimulation protocols for a variety of modalities in rodents with fMRI. Cortical perception of the natural world relies on the formation of multi-dimensional representation of stimuli impinging on the different sensory systems, leading to the hypothesis that a sensory stimulus may have very different neurophysiologic outcome(s) when paired with a near simultaneous event in another modality. Before approaching this level of complexity, reliable measures must be obtained of the relatively small changes in the BOLD signal and other neurophysiologic markers (electrical activity, blood flow) induced by different peripheral stimuli. Here we describe different tactile (i.e., forepaw, whisker) and non-tactile (i.e., olfactory, visual) sensory paradigms applied to the anesthetized rat. The main focus is on development and validation of methods for reproducible stimulation of each sensory modality applied independently or in conjunction with one another, both inside and outside the magnet. We discuss similarities and/or differences across the sensory systems as well as advantages they may have for studying essential neuroscientific questions. We envisage that the different sensory paradigms described here may be applied directly to studies of multi-sensory interactions in anesthetized rats, en route to a rudimentary understanding of the awake functioning brain where various sensory cues presumably

  13. Experiences and Explanations of ADHD

    DEFF Research Database (Denmark)

    Nielsen, Mikka

    Research on Attention Deficit Hyperactivity Disorder (ADHD) usually presents the disorder from either a neurobiological perspective, describing the disorder as an impairment in executive functions, or from a critical, sociological perspective, whereby ADHD is explained as a consequence...... of the medicalization of deviant behaviour. Neither of these perspectives tells us about the experience of living with ADHD, or explains how ADHD unfolds within specific contexts and relations. Experiences and Explanations of ADHD addresses this lacuna by exploring bodily experiences of ADHD and people’s experiences...... of obtaining a diagnosis. Drawing on in-depth interviews with adults diagnosed with ADHD, the book provides an examination of how the diagnosis is understood, used and acted upon by the people receiving the diagnosis. This book delves into the phenomenology of ADHD and uncovers the experiences of a highly...

  14. Negotiating explanations: doctor-patient communication with patients with medically unexplained symptoms-a qualitative analysis.

    Science.gov (United States)

    den Boeft, Madelon; Huisman, Daniëlle; Morton, LaKrista; Lucassen, Peter; van der Wouden, Johannes C; Westerman, Marjan J; van der Horst, Henriëtte E; Burton, Christopher D

    2017-02-01

    Patients with medically unexplained physical symptoms (MUPS) seek explanations for their symptoms, but often find general practitioners (GPs) unable to deliver these. Different methods of explaining MUPS have been proposed. Little is known about how communication evolves around these explanations. To examine the dialogue between GPs and patients related to explanations in a community-based clinic for MUPS. We categorized dialogue types and dialogue outcomes. Patients were ≥18 years with inclusion criteria for moderate MUPS: ≥2 referrals to specialists, ≥1 functional syndrome/symptoms, ≥10 on the Patient Health Questionnaire-15 and GP's judgement that symptoms were unexplained. We analysed transcripts of 112 audio-recorded consultations (39 patients and 5 GPs) from two studies on the Symptoms Clinic Intervention, a consultation intervention for MUPS in primary care. We used constant comparative analysis to code and classify dialogue types and outcomes. We extracted 115 explanation sequences. We identified four dialogue types, differing in the extent to which the GP or patient controlled the dialogue. We categorized eight outcomes of the sequences, ranging from acceptance to rejection by the patient. The most common outcome was holding (conversation suspended in an unresolved state), followed by acceptance. Few explanations were rejected by the patient. Co-created explanations by patient and GP were most likely to be accepted. We developed a classification of dialogue types and outcomes in relation to explanations offered by GPs for MUPS patients. While it requires further validation, it provides a framework, which can be used for teaching, evaluation of practice and research. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Evidence that transcranial direct current stimulation (tDCS) generates little-to-no reliable neurophysiologic effect beyond MEP amplitude modulation in healthy human subjects: A systematic review.

    Science.gov (United States)

    Horvath, Jared Cooney; Forte, Jason D; Carter, Olivia

    2015-01-01

    Transcranial direct current stimulation (tDCS) is a form of neuromodulation that is increasingly being utilized to examine and modify a number of cognitive and behavioral measures. The theoretical mechanisms by which tDCS generates these changes are predicated upon a rather large neurophysiological literature. However, a robust systematic review of this neurophysiological data has not yet been undertaken. tDCS data in healthy adults (18-50) from every neurophysiological outcome measure reported by at least two different research groups in the literature was collected. When possible, data was pooled and quantitatively analyzed to assess significance. When pooling was not possible, data was qualitatively compared to assess reliability. Of the 30 neurophysiological outcome measures reported by at least two different research groups, tDCS was found to have a reliable effect on only one: MEP amplitude. Interestingly, the magnitude of this effect has been significantly decreasing over the last 14 years. Our systematic review does not support the idea that tDCS has a reliable neurophysiological effect beyond MEP amplitude modulation - though important limitations of this review (and conclusion) are discussed. This work raises questions concerning the mechanistic foundations and general efficacy of this device - the implications of which extend to the steadily increasing tDCS psychological literature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Neurophysiological approach to tinnitus patients.

    Science.gov (United States)

    Jastreboff, P J; Gray, W C; Gold, S L

    1996-03-01

    The principal postulate of the neurophysiological model of tinnitus is that all levels of the auditory pathways and several nonauditory systems play essential roles in each case of tinnitus, stressing the dominance of nonauditory systems in determining the level of tinnitus annoyance. Thus it has been proposed to treat tinnitus by inducing and facilitating habituation to the tinnitus signal. The goal is to reach the stage at which, although patients may perceive tinnitus as unchanged when they focus on it, they are otherwise not aware of tinnitus. Furthermore, even when perceived, tinnitus does not evoke annoyance. Habituation is achieved by directive counseling combined with low-level, broad-band noise generated by wearable generators, and environmental sounds, according to a specific protocol. For habituation to occur, it is imperative to avoid masking tinnitus by these sounds. Since 1991, > 500 tinnitus patients have been seen in our center. About 40% exhibited hyperacusis to varying degrees. A survey of > 100 patients revealed > 80% of significant improvement in groups of patients treated with the full protocol involving counseling and the use of noise generators. Notably, in patients who received counseling only, the success rate was < 20%. The improvement in hyperacusis was observed in approximately 90% of treated patients.

  17. Social class, sense of control, and social explanation.

    Science.gov (United States)

    Kraus, Michael W; Piff, Paul K; Keltner, Dacher

    2009-12-01

    Lower social class is associated with diminished resources and perceived subordinate rank. On the basis of this analysis, the authors predicted that social class would be closely associated with a reduced sense of personal control and that this association would explain why lower class individuals favor contextual over dispositional explanations of social events. Across 4 studies, lower social class individuals, as measured by subjective socioeconomic status (SES), endorsed contextual explanations of economic trends, broad social outcomes, and emotion. Across studies, the sense of control mediated the relation between subjective SES and contextual explanations, and this association was independent of objective SES, ethnicity, political ideology, and self-serving biases. Finally, experimentally inducing a higher sense of control attenuated the tendency for lower subjective SES individuals to make more contextual explanations (Study 4). Implications for future research on social class as well as theoretical distinctions between objective SES and subjective SES are discussed.

  18. Disorder-specific and shared neurophysiological impairments of attention and inhibition in women with attention-deficit/hyperactivity disorder and women with bipolar disorder.

    Science.gov (United States)

    Michelini, G; Kitsune, G L; Hosang, G M; Asherson, P; McLoughlin, G; Kuntsi, J

    2016-02-01

    In adults, attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) have certain overlapping symptoms, which can lead to uncertainty regarding the boundaries of the two disorders. Despite evidence of cognitive impairments in both disorders separately, such as in attentional and inhibitory processes, data on direct comparisons across ADHD and BD on cognitive-neurophysiological measures are as yet limited. We directly compared cognitive performance and event-related potential measures from a cued continuous performance test in 20 women with ADHD, 20 women with BD (currently euthymic) and 20 control women. The NoGo-N2 was attenuated in women with BD, reflecting reduced conflict monitoring, compared with women with ADHD and controls (both p < 0.05). Both ADHD and BD groups showed a reduced NoGo-P3, reflecting inhibitory control, compared with controls (both p < 0.05). In addition, the contingent negative variation was significantly reduced in the ADHD group (p = 0.05), with a trend in the BD group (p = 0.07), compared with controls. These findings indicate potential disorder-specific (conflict monitoring) and overlapping (inhibitory control, and potentially response preparation) neurophysiological impairments in women with ADHD and women with BD. The identified neurophysiological parameters further our understanding of neurophysiological impairments in women with ADHD and BD, and are candidate biomarkers that may aid in the identification of the diagnostic boundaries of the two disorders.

  19. Data-driven analysis of simultaneous EEG/fMRI reveals neurophysiological phenotypes of impulse control.

    Science.gov (United States)

    Schmüser, Lena; Sebastian, Alexandra; Mobascher, Arian; Lieb, Klaus; Feige, Bernd; Tüscher, Oliver

    2016-09-01

    Response inhibition is the ability to suppress inadequate but prepotent or ongoing response tendencies. A fronto-striatal network is involved in these processes. Between-subject differences in the intra-individual variability have been suggested to constitute a key to pathological processes underlying impulse control disorders. Single-trial EEG/fMRI analysis allows to increase sensitivity for inter-individual differences by incorporating intra-individual variability. Thirty-eight healthy subjects performed a visual Go/Nogo task during simultaneous EEG/fMRI. Of 38 healthy subjects, 21 subjects reliably showed Nogo-related ICs (Nogo-IC-positive) while 17 subjects (Nogo-IC-negative) did not. Comparing both groups revealed differences on various levels: On trait level, Nogo-IC-negative subjects scored higher on questionnaires regarding attention deficit/hyperactivity disorder; on a behavioral level, they displayed slower response times (RT) and higher intra-individual RT variability while both groups did not differ in their inhibitory performance. On the neurophysiological level, Nogo-IC-negative subjects showed a hyperactivation of left inferior frontal cortex/insula and left putamen as well as significantly reduced P3 amplitudes. Thus, a data-driven approach for IC classification and the resulting presence or absence of early Nogo-specific ICs as criterion for group selection revealed group differences at behavioral and neurophysiological levels. This may indicate electrophysiological phenotypes characterized by inter-individual variations of neural and behavioral correlates of impulse control. We demonstrated that the inter-individual difference in an electrophysiological correlate of response inhibition is correlated with distinct, potentially compensatory neural activity. This may suggest the existence of electrophysiologically dissociable phenotypes of behavioral and neural motor response inhibition with the Nogo-IC-positive phenotype possibly providing

  20. Reading the mind in the touch: Neurophysiological specificity in the communication of emotions by touch.

    Science.gov (United States)

    Kirsch, Louise P; Krahé, Charlotte; Blom, Nadia; Crucianelli, Laura; Moro, Valentina; Jenkinson, Paul M; Fotopoulou, Aikaterini

    2017-05-29

    Touch is central to interpersonal interactions. Touch conveys specific emotions about the touch provider, but it is not clear whether this is a purely socially learned function or whether it has neurophysiological specificity. In two experiments with healthy participants (N = 76 and 61) and one neuropsychological single case study, we investigated whether a type of touch characterised by peripheral and central neurophysiological specificity, namely the C tactile (CT) system, can communicate specific emotions and mental states. We examined the specificity of emotions elicited by touch delivered at CT-optimal (3cm/s) and CT-suboptimal (18cm/s) velocities (Experiment 1) at different body sites which contain (forearm) vs. do not contain (palm of the hand) CT fibres (Experiment 2). Blindfolded participants were touched without any contextual cues, and were asked to identify the touch provider's emotion and intention. Overall, CT-optimal touch (slow, gentle touch on the forearm) was significantly more likely than other types of touch to convey arousal, lust or desire. Affiliative emotions such as love and related intentions such as social support were instead reliably elicited by gentle touch, irrespective of CT-optimality, suggesting that other top-down factors contribute to these aspects of tactile social communication. To explore the neural basis of this communication, we also tested this paradigm in a stroke patient with right perisylvian damage, including the posterior insular cortex, which is considered as the primary cortical target of CT afferents, but excluding temporal cortex involvement that has been linked to more affiliative aspects of CT-optimal touch. His performance suggested an impairment in 'reading' emotions based on CT-optimal touch. Taken together, our results suggest that the CT system can add specificity to emotional and social communication, particularly with regards to feelings of desire and arousal. On the basis of these findings, we speculate

  1. [A Matter of Nerves - Applied Neurophysiology of Female Sexuality].

    Science.gov (United States)

    Bischof, Karoline

    2015-06-17

    Sexual problems are often attributed to psychological or physical deficits that are difficult to modify, or to a poor lover. In contrast, the neurophysiological interaction between body and brain can be understood as fundamental for the genital and emotional experience of sexuality. Neuropsychological discoveries and clinical observations show that elevated muscle tension, superficial breathing and reduced body movement, as employed by many individuals during sexual arousal, will limit the perception of arousal and the degree of sexual pleasure. In contrast, deep breathing and variations in movement and muscle tension support it. Through the use of self awareness exercises and physical learning steps, patients can integrate their sexuality and increases its resistance to psychological, medical and relational interferences.

  2. Explanation and teleology in Aristotle's Philosophy of Nature

    NARCIS (Netherlands)

    Leunissen, Mariska Elisabeth Maria Philomena Johannes

    2007-01-01

    This dissertation explores Aristotle’s use of teleology as a principle of explanation, especially as it is used in the natural treatises. Its main purposes are, first, to determine the function, structure, and explanatory power of teleological explanations in four of Aristotle’s natural treatises,

  3. Risk and Resilience: Early Manipulation of Macaque Social Experience and Persistent Behavioral and Neurophysiological Outcomes

    Science.gov (United States)

    Stevens, Hanna E.; Leckman, James F.; Coplan, Jeremy D.; Suomi, Stephen J.

    2009-01-01

    A literature review on macaque monkeys finds that peer rearing of young macaques and rearing of young macaques by mothers that are undergoing variable foraging conditions result in emotional and neurophysiological disturbance. Certain genotypes contribute to resilience to this disturbance. The findings have implications to child mental health and…

  4. Neurophysiological criteria in the diagnosis of different clinical types of Guillain-Barre syndrome.

    Science.gov (United States)

    Kalita, J; Misra, U K; Das, M

    2008-03-01

    The diagnostic yield of various neurophysiological criteria may vary in different subforms of Guillain-Barre syndrome (GBS), whose prevalence varies in different geographical areas. To evaluate the sensitivity of various neurophysiological criteria in different clinical subtypes of GBS, and their relationship with severity, duration and outcome. Consecutive patients with GBS underwent detailed clinical evaluation. Severity was graded on a scale from 0 to 10. Motor and sensory nerve conductions and F wave studies were performed. The diagnostic sensitivity of Albers et al (set 1), Cornblath (set 2), Ho et al (set 3), Dutch GBS study group (set 4), Italian GBS study group (set 5) and Albers and Kelly (set 6) criteria were evaluated and correlated with clinical subtypes of GBS, duration, severity and outcome. There were 51 patients. Mean disability was 6.8; 34 patients were bedridden and five needed a ventilator. Clinical presentation was pure motor in 31, motorsensory in 18 and pure sensory in two patients. The sensitivity of nerve conduction study in the diagnosis of GBS was highest in set 1 (88.2%) followed by set 3 (86.3%) and set 4 (82.4%) and lowest in set 2 (39.2%). The diagnostic yield of sets 1, 3 and 4 were also higher than sets 2, 5 and 6 in different clinical subtypes of GBS. As per Ho et al, patients could be categorised into acute inflammatory demyelinating polyradiculoneuropathy (44 (86.3%)), acute motor axonal neuropathy (4 (7.8%)) and acute motor sensory axonal neuropathy (3 (5.9%)). One (2%) patient died, 22.4% had complete, 57.1% partial and 18.4% poor recovery at 3 months. Outcome was related to severity of illness and compound muscle action potential (CMAP) amplitude. The sensitivity of different neurophysiological criteria in the diagnosis of Indian GBS patients varied from 39.2% to 88.2%. The outcome was related to severity of illness and CMAP amplitude.

  5. Hierarchy, causation and explanation: ubiquity, locality and pluralism

    Science.gov (United States)

    Love, Alan C.

    2012-01-01

    The ubiquity of top-down causal explanations within and across the sciences is prima facie evidence for the existence of top-down causation. Much debate has been focused on whether top-down causation is coherent or in conflict with reductionism. Less attention has been given to the question of whether these representations of hierarchical relations pick out a single, common hierarchy. A negative answer to this question undermines a commonplace view that the world is divided into stratified ‘levels’ of organization and suggests that attributions of causal responsibility in different hierarchical representations may not have a meaningful basis for comparison. Representations used in top-down and bottom-up explanations are primarily ‘local’ and tied to distinct domains of science, illustrated here by protein structure and folding. This locality suggests that no single metaphysical account of hierarchy for causal relations to obtain within emerges from the epistemology of scientific explanation. Instead, a pluralist perspective is recommended—many different kinds of top-down causation (explanation) can exist alongside many different kinds of bottom-up causation (explanation). Pluralism makes plausible why different senses of top-down causation can be coherent and not in conflict with reductionism, thereby illustrating a productive interface between philosophical analysis and scientific inquiry. PMID:23386966

  6. Flip-Floppers and Wafflers: Explanations and Repositioning

    DEFF Research Database (Denmark)

    Robison, Joshua

    to this literature by showing that repositioning’s influence on evaluations depends on beliefs citizens make concerning why the policy switch occurred, beliefs that are, in turn, structured by the communication environment surrounding such switches. Specifically, I use two large national survey experiments to show...... that repositioning elites who provide a satisfactory explanation for their change in position escape evaluative harm from their actions and that this occurs even among individuals who lost proximity from the elite’s change in position and among those from a different party as the elite. This study thus has important...

  7. Teacher Explanation of Physics Concepts: A Video Study

    Science.gov (United States)

    Geelan, David

    2013-01-01

    Video recordings of Year 11 physics lessons were analyzed to identify key features of teacher explanations. Important features of the explanations used included teachers' ability to move between qualitative and quantitative modes of discussion, attention to what students require to succeed in high stakes examinations, thoughtful use of…

  8. An Explanation of Nakamoto's Analysis of Double-spend Attacks

    OpenAIRE

    Ozisik, A. Pinar; Levine, Brian Neil

    2017-01-01

    The fundamental attack against blockchain systems is the double-spend attack. In this tutorial, we provide a very detailed explanation of just one section of Satoshi Nakamoto's original paper where the attack's probability of success is stated. We show the derivation of the mathematics relied upon by Nakamoto to create a model of the attack. We also validate the model with a Monte Carlo simulation, and we determine which model component is not perfect.

  9. Promoting Vicarious Learning of Physics Using Deep Questions with Explanations

    Science.gov (United States)

    Craig, Scotty D.; Gholson, Barry; Brittingham, Joshua K.; Williams, Joah L.; Shubeck, Keith T.

    2012-01-01

    Two experiments explored the role of vicarious "self" explanations in facilitating student learning gains during computer-presented instruction. In Exp. 1, college students with low or high knowledge on Newton's laws were tested in four conditions: (a) monologue (M), (b) questions (Q), (c) explanation (E), and (d) question + explanation (Q + E).…

  10. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins

    Science.gov (United States)

    Camina, Eduardo; Güell, Francisco

    2017-01-01

    This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and ordering the latest scientific advances related to this subject. The main forms of memory presented include sensory memory, short-term memory, and long-term memory. Information from the world around us is first stored by sensory memory, thus enabling the storage and future use of such information. Short-term memory (or memory) refers to information processed in a short period of time. Long-term memory allows us to store information for long periods of time, including information that can be retrieved consciously (explicit memory) or unconsciously (implicit memory). PMID:28713278

  11. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins.

    Science.gov (United States)

    Camina, Eduardo; Güell, Francisco

    2017-01-01

    This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and ordering the latest scientific advances related to this subject. The main forms of memory presented include sensory memory, short-term memory, and long-term memory. Information from the world around us is first stored by sensory memory, thus enabling the storage and future use of such information. Short-term memory (or memory) refers to information processed in a short period of time. Long-term memory allows us to store information for long periods of time, including information that can be retrieved consciously (explicit memory) or unconsciously (implicit memory).

  12. The Neuroanatomical, Neurophysiological and Psychological Basis of Memory: Current Models and Their Origins

    Directory of Open Access Journals (Sweden)

    Eduardo Camina

    2017-06-01

    Full Text Available This review aims to classify and clarify, from a neuroanatomical, neurophysiological, and psychological perspective, different memory models that are currently widespread in the literature as well as to describe their origins. We believe it is important to consider previous developments without which one cannot adequately understand the kinds of models that are now current in the scientific literature. This article intends to provide a comprehensive and rigorous overview for understanding and ordering the latest scientific advances related to this subject. The main forms of memory presented include sensory memory, short-term memory, and long-term memory. Information from the world around us is first stored by sensory memory, thus enabling the storage and future use of such information. Short-term memory (or memory refers to information processed in a short period of time. Long-term memory allows us to store information for long periods of time, including information that can be retrieved consciously (explicit memory or unconsciously (implicit memory.

  13. A Multimodal, SU-8 - Platinum - Polyimide Microelectrode Array for Chronic In Vivo Neurophysiology.

    Directory of Open Access Journals (Sweden)

    Gergely Márton

    Full Text Available Utilization of polymers as insulator and bulk materials of microelectrode arrays (MEAs makes the realization of flexible, biocompatible sensors possible, which are suitable for various neurophysiological experiments such as in vivo detection of local field potential changes on the surface of the neocortex or unit activities within the brain tissue. In this paper the microfabrication of a novel, all-flexible, polymer-based MEA is presented. The device consists of a three dimensional sensor configuration with an implantable depth electrode array and brain surface electrodes, allowing the recording of electrocorticographic (ECoG signals with laminar ones, simultaneously. In vivo recordings were performed in anesthetized rat brain to test the functionality of the device under both acute and chronic conditions. The ECoG electrodes recorded slow-wave thalamocortical oscillations, while the implanted component provided high quality depth recordings. The implants remained viable for detecting action potentials of individual neurons for at least 15 weeks.

  14. Algorithms and Their Explanations

    NARCIS (Netherlands)

    Benini, M.; Gobbo, F.; Beckmann, A.; Csuhaj-Varjú, E.; Meer, K.

    2014-01-01

    By analysing the explanation of the classical heapsort algorithm via the method of levels of abstraction mainly due to Floridi, we give a concrete and precise example of how to deal with algorithmic knowledge. To do so, we introduce a concept already implicit in the method, the ‘gradient of

  15. Consensus on the use of neurophysiological tests in the intensive care unit (ICU): electroencephalogram (EEG), evoked potentials (EP), and electroneuromyography (ENMG)

    DEFF Research Database (Denmark)

    Guørit, J.M.; Amantini, A.; Amodio, P.

    2009-01-01

    STUDY AIM: To provide a consensus of European leading authorities about the optimal use of clinical neurophysiological (CN) tests (electroencephalogram [EEG]; evoked potentials [EP]; electroneuromyography [ENMG]) in the intensive care unit (ICU) and, particularly, about the way to make these tests...... contribution to all other experts. A complete consensus has been reached when submitting the manuscript. RESULTS: What the group considered as the best classification systems for EEG and EP abnormalities in the ICU is first presented. CN tests are useful for diagnosis (epilepsy, brain death, and neuromuscular...

  16. Cross-Level Effects Between Neurophysiology and Communication During Team Training.

    Science.gov (United States)

    Gorman, Jamie C; Martin, Melanie J; Dunbar, Terri A; Stevens, Ronald H; Galloway, Trysha L; Amazeen, Polemnia G; Likens, Aaron D

    2016-02-01

    We investigated cross-level effects, which are concurrent changes across neural and cognitive-behavioral levels of analysis as teams interact, between neurophysiology and team communication variables under variations in team training. When people work together as a team, they develop neural, cognitive, and behavioral patterns that they would not develop individually. It is currently unknown whether these patterns are associated with each other in the form of cross-level effects. Team-level neurophysiology and latent semantic analysis communication data were collected from submarine teams in a training simulation. We analyzed whether (a) both neural and communication variables change together in response to changes in training segments (briefing, scenario, or debriefing), (b) neural and communication variables mutually discriminate teams of different experience levels, and (c) peak cross-correlations between neural and communication variables identify how the levels are linked. Changes in training segment led to changes in both neural and communication variables, neural and communication variables mutually discriminated between teams of different experience levels, and peak cross-correlations indicated that changes in communication precede changes in neural patterns in more experienced teams. Cross-level effects suggest that teamwork is not reducible to a fundamental level of analysis and that training effects are spread out across neural and cognitive-behavioral levels of analysis. Cross-level effects are important to consider for theories of team performance and practical aspects of team training. Cross-level effects suggest that measurements could be taken at one level (e.g., neural) to assess team experience (or skill) on another level (e.g., cognitive-behavioral). © 2015, Human Factors and Ergonomics Society.

  17. Neurophysiological intraoperative monitoring during an optic nerve schwannoma removal.

    Science.gov (United States)

    San-Juan, Daniel; Escanio Cortés, Manuel; Tena-Suck, Martha; Orozco Garduño, Adolfo Josué; López Pizano, Jesús Alejandro; Villanueva Domínguez, Jonathan; Fernández Gónzalez-Aragón, Maricarmen; Gómez-Amador, Juan Luis

    2017-10-01

    This paper reports the case of a patient with optic nerve schwannoma and the first use of neurophysiological intraoperative monitoring of visual evoked potentials during the removal of such tumor with no postoperative visual damage. Schwannomas are benign neoplasms of the peripheral nervous system arising from the neural crest-derived Schwann cells, these tumors are rarely located in the optic nerve and the treatment consists on surgical removal leading to high risk of damage to the visual pathway. Case report of a thirty-year-old woman with an optic nerve schwannoma. The patient underwent surgery for tumor removal on the left optic nerve through a left orbitozygomatic approach with intraoperative monitoring of left II and III cranial nerves. We used Nicolet Endeavour CR IOM (Carefusion, Middleton WI, USA) to performed visual evoked potentials stimulating binocularly with LED flash goggles with the patient´s eyes closed and direct epidural optic nerve stimulation delivering rostral to the tumor a rectangular current pulse. At follow up examinations 7 months later, the left eye visual acuity was 20/60; Ishihara score was 8/8 in both eyes; the right eye photomotor reflex was normal and left eye was mydriatic and arreflectic; optokinetic reflex and ocular conjugate movements were normal. In this case, the epidural direct electrical stimulation of optic nerve provided stable waveforms during optic nerve schwannoma resection without visual loss.

  18. PL-DA-PS: A hardware architecture and software toolbox for neurophysiology requiring complex visual stimuli and online behavioral control

    Directory of Open Access Journals (Sweden)

    Kyler M. Eastman

    2012-01-01

    Full Text Available Neurophysiological studies in awake, behaving primates (both human and nonhuman primates have focused with increasing scrutiny on the temporal relationship between neural signals and behaviors. Consequently, laboratories are often faced with the problem of developing experimental equipment that can support data recording with high temporal precision and also be flexible enough to accommodate a wide variety of experimental paradigms. To this end, we have developed an architecture that integrates several modern pieces of equipment, but still grants experimenters a high degree of flexibility. Our hardware architecture and software tools take advantage of three popular and powerful technologies: the PLexon apparatus for neurophysiological recordings (Plexon, Inc., Dallas TX, a DAtapixx box (Vpixx Technologies, Saint-Bruno, QC, Canada for analog, digital, and video signal input-output control, and the PSychtoolbox MATLAB toolbox for stimulus generation (Brainard, 1997. The PL-DA-PS (Platypus system is designed to support the study of the visual systems of awake, behaving primates during multi-electrode neurophysiological recordings, but can be easily applied to other related domains. Despite its wide range of capabilities and support for cutting-edge video displays and neural recording systems, the PLDAPS system is simple enough for someone with basic MATLAB programming skills to design their own experiments.

  19. The geomagnetic field - An explanation for the microturbulence in coaxial gun plasmas

    International Nuclear Information System (INIS)

    Mather, J.W.; Ahluwalia, H.S.

    1988-01-01

    The authors describe the complexity introduced by the geomagnetic field in several regions of a coaxial gun plasma device. It is shown that the annihilation of the swept-up geomagnetic flux, trapped within the highly compressed turbulent plasma, provides an explanation for varied performance and experimental results

  20. The clinical and neurophysiological characteristics of the deja vu phenomenon in epilepsy

    OpenAIRE

    P. N. Vlasov; A. V. Chervyakov; G. R. Drozhzhina; М. V. Antonyuk; N. V. Orekhova; V. V. Gnezditsky; T. Yu. Noskova; P. A. Fedin

    2012-01-01

    Objective: to study the clinical and neurophysiological characteristics of the deja vu phenomenon in epilepsy. Patients and methods. The manifestations of the dВjЕ vu phenomenon were compared in 154 examinees in two groups: 1) 139 healthy individuals and 2) 25 patients with epilepsy (mean age 25.17±9.19 years; women, 63.2%) The characteristics of the phenomenon were determined, by questioning the examinees; 12—16-hour ambulatory electroencephalogram (EEG) monitoring was made. Results. The dej...

  1. [Clinical and neurophysiological heterogeneity of attention deficit hyperactivity disorder].

    Science.gov (United States)

    Chutko, L S; Yakovenko, E A; Surushkina, S Yu; Anisimova, T I; Kropotov, Yu D

    To determine clinical/neurophysiological characteristics of different forms of attention deficit hyperactivity disorder (ADHD) and the efficacy of treatment with cerebrolysin. Sixty children, aged 9 to 12 years, with ADHD were examined using clinical and electroencephalographic methods. Idiopathic and residual-organic forms were compared. The study shows significantly higher levels of impulsivity and hyperactivity in children with residual-organic form of the disease. There were significant differences in the amplitude component of engaging in action (P3 Go) and the amplitude of the action suppression component (P3 NOGO) in patients with different forms of ADHD. The high clinical efficacy (improvement in 70.0% of patients with idiopathic form of ADHD and 86.7% of patients with residual-organic form of the disease) was found.

  2. sleep disorders due to neuroinfections: clinical symptoms, neurochemistry and neurophysiology V.B. Voitenkov1, N.V. Skripchenko1, Y.E. Zueva 2

    Directory of Open Access Journals (Sweden)

    V. B. Voitenkov

    2015-01-01

    Full Text Available In our review we present data on sleep disturbances in neuroinfections (encephalitis and meningitis, their clinical signs, neurochemistry and neurophysiology. These signs include lethargy, narcolepsy, sleep apnoe, sleep structure disruptions and may appear in acute period and as a sequelae of the disease. Reticular formation involvement seems to be the main reason for such sleep disorders. GABA and orexin systems disruption may play the key role in them. Neurophysiology evaluation of such disorders includes polysomnography, EEG-monitoring, brainstem acoustic evoked potentials and H-reflex investigation. 

  3. Bothered by abstractness or engaged by cohesion? Experts' explanations enhance novices' deep-learning.

    Science.gov (United States)

    Lachner, Andreas; Nückles, Matthias

    2015-03-01

    Experts' explanations have been shown to better enhance novices' transfer as compared with advanced students' explanations. Based on research on expertise and text comprehension, we investigated whether the abstractness or the cohesion of experts' and intermediates' explanations accounted for novices' learning. In Study 1, we showed that the superior cohesion of experts' explanations accounted for most of novices' transfer, whereas the degree of abstractness did not impact novices' transfer performance. In Study 2, we investigated novices' processing while learning with experts' and intermediates' explanations. We found that novices studying experts' explanations actively self-regulated their processing of the explanations, as they showed mainly deep-processing activities, whereas novices learning with intermediates' explanations were mainly engaged in shallow-processing activities by paraphrasing the explanations. Thus, we concluded that subject-matter expertise is a crucial prerequisite for instructors. Despite the abstract character of experts' explanations, their subject-matter expertise enables them to generate highly cohesive explanations that serve as a valuable scaffold for students' construction of flexible knowledge by engaging them in deep-level processing. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  4. Correlation between muscle electrical impedance data and standard neurophysiologic parameters after experimental neurogenic injury

    International Nuclear Information System (INIS)

    Ahad, M; Rutkove, S B

    2010-01-01

    Previous work has shown that electrical impedance measurements of muscle can assist in quantifying the degree of muscle atrophy resulting from neuronal injury, with impedance values correlating strongly with standard clinical parameters. However, the relationship between such data and neurophysiologic measurements is unexplored. In this study, 24 Wistar rats underwent sciatic crush, with measurement of the 2–1000 kHz impedance spectrum, standard electrophysiological measures, including nerve conduction studies, needle electromyography, and motor unit number estimation (MUNE) before and after sciatic crush, with animals assessed weekly for 4 weeks post-injury. All electrical impedance values, including a group of 'collapsed' variables, in which the spectral characteristics were reduced to single values, showed reductions as high as 47.2% after sciatic crush, paralleling and correlating with changes in compound motor action potential amplitude, conduction velocity and most closely to MUNE, but not to the presence of fibrillation potentials observed on needle electromyography. These results support the concept that localized impedance measurements can serve as surrogate makers of nerve injury; these measurements may be especially useful in assessing nerve injury impacting proximal or axial muscles where standard quantitative neurophysiologic methods such as nerve conduction or MUNE cannot be readily performed

  5. Explanation and observability of diffraction in time

    International Nuclear Information System (INIS)

    Torrontegui, E.; Muga, J. G.; Munoz, J.; Ban, Yue

    2011-01-01

    Diffraction in time (DIT) is a fundamental phenomenon in quantum dynamics due to time-dependent obstacles and slits. It is formally analogous to diffraction of light, and is expected to play an increasing role in the design of coherent matter wave sources, as in the atom laser, to analyze time-of-flight information and emission from ultrafast pulsed excitations, and in applications of coherent matter waves in integrated atom-optical circuits. We demonstrate that DIT emerges robustly in quantum waves emitted by an exponentially decaying source and provide a simple explanation of the phenomenon, as an interference of two characteristic velocities. This allows for its controllability and optimization.

  6. The Limits of Materialism: Auspicious for Teleological Explanation?

    Science.gov (United States)

    Athearn, Daniel

    2012-09-01

    The idea that scientific explanation runs up against certain inherent limits beyond which the field is open for other kinds of explanation is based on flawed assumptions. Modern physical knowledge, as I read it, does contain at least one important implication for theology having to do with how "Creation" is understood, if indeed the term remains usable and suitable.

  7. Reasoning with alternative explanations in physics: The cognitive accessibility rule

    Science.gov (United States)

    Heckler, Andrew F.; Bogdan, Abigail M.

    2018-06-01

    A critical component of scientific reasoning is the consideration of alternative explanations. Recognizing that decades of cognitive psychology research have demonstrated that relative cognitive accessibility, or "what comes to mind," strongly affects how people reason in a given context, we articulate a simple "cognitive accessibility rule", namely that alternative explanations are considered less frequently when an explanation with relatively high accessibility is offered first. In a series of four experiments, we test the cognitive accessibility rule in the context of consideration of alternative explanations for six physical scenarios commonly found in introductory physics curricula. First, we administer free recall and recognition tasks to operationally establish and distinguish between the relative accessibility and availability of common explanations for the physical scenarios. Then, we offer either high or low accessibility explanations for the physical scenarios and determine the extent to which students consider alternatives to the given explanations. We find two main results consistent across algebra- and calculus-based university level introductory physics students for multiple answer formats. First, we find evidence that, at least for some contexts, most explanatory factors are cognitively available to students but not cognitively accessible. Second, we empirically verify the cognitive accessibility rule and demonstrate that the rule is strongly predictive, accounting for up to 70% of the variance of the average student consideration of alternative explanations across scenarios. Overall, we find that cognitive accessibility can help to explain biases in the consideration of alternatives in reasoning about simple physical scenarios, and these findings lend support to the growing number of science education studies demonstrating that tasks relevant to science education curricula often involve rapid, automatic, and potentially predictable processes and

  8. Neuropsychological and neurophysiological benefits from white noise in children with and without ADHD

    OpenAIRE

    Baijot, Simon; Slama, Hichem; S?derlund, G?ran; Dan, Bernard; Deltenre, Paul; Colin, C?cile; Deconinck, Nicolas

    2016-01-01

    Background Optimal stimulation theory and moderate brain arousal (MBA) model hypothesize that extra-task stimulation (e.g. white noise) could improve cognitive functions of children with attention-deficit/hyperactivity disorder (ADHD). We investigate benefits of white noise on attention and inhibition in children with and without ADHD (7?12?years old), both at behavioral and at neurophysiological levels. Methods Thirty children with and without ADHD performed a visual cued Go/Nogo task in two...

  9. Explanation-based learning in infancy.

    Science.gov (United States)

    Baillargeon, Renée; DeJong, Gerald F

    2017-10-01

    In explanation-based learning (EBL), domain knowledge is leveraged in order to learn general rules from few examples. An explanation is constructed for initial exemplars and is then generalized into a candidate rule that uses only the relevant features specified in the explanation; if the rule proves accurate for a few additional exemplars, it is adopted. EBL is thus highly efficient because it combines both analytic and empirical evidence. EBL has been proposed as one of the mechanisms that help infants acquire and revise their physical rules. To evaluate this proposal, 11- and 12-month-olds (n = 260) were taught to replace their current support rule (that an object is stable when half or more of its bottom surface is supported) with a more sophisticated rule (that an object is stable when half or more of the entire object is supported). Infants saw teaching events in which asymmetrical objects were placed on a base, followed by static test displays involving a novel asymmetrical object and a novel base. When the teaching events were designed to facilitate EBL, infants learned the new rule with as few as two (12-month-olds) or three (11-month-olds) exemplars. When the teaching events were designed to impede EBL, however, infants failed to learn the rule. Together, these results demonstrate that even infants, with their limited knowledge about the world, benefit from the knowledge-based approach of EBL.

  10. Assessing motor imagery in brain-computer interface training: Psychological and neurophysiological correlates.

    Science.gov (United States)

    Vasilyev, Anatoly; Liburkina, Sofya; Yakovlev, Lev; Perepelkina, Olga; Kaplan, Alexander

    2017-03-01

    Motor imagery (MI) is considered to be a promising cognitive tool for improving motor skills as well as for rehabilitation therapy of movement disorders. It is believed that MI training efficiency could be improved by using the brain-computer interface (BCI) technology providing real-time feedback on person's mental attempts. While BCI is indeed a convenient and motivating tool for practicing MI, it is not clear whether it could be used for predicting or measuring potential positive impact of the training. In this study, we are trying to establish whether the proficiency in BCI control is associated with any of the neurophysiological or psychological correlates of motor imagery, as well as to determine possible interrelations among them. For that purpose, we studied motor imagery in a group of 19 healthy BCI-trained volunteers and performed a correlation analysis across various quantitative assessment metrics. We examined subjects' sensorimotor event-related EEG events, corticospinal excitability changes estimated with single-pulse transcranial magnetic stimulation (TMS), BCI accuracy and self-assessment reports obtained with specially designed questionnaires and interview routine. Our results showed, expectedly, that BCI performance is dependent on the subject's capability to suppress EEG sensorimotor rhythms, which in turn is correlated with the idle state amplitude of those oscillations. Neither BCI accuracy nor the EEG features associated with MI were found to correlate with the level of corticospinal excitability increase during motor imagery, and with assessed imagery vividness. Finally, a significant correlation was found between the level of corticospinal excitability increase and kinesthetic vividness of imagery (KVIQ-20 questionnaire). Our results suggest that two distinct neurophysiological mechanisms might mediate possible effects of motor imagery: the non-specific cortical sensorimotor disinhibition and the focal corticospinal excitability increase

  11. Serial neurophysiological and neurophysiological examinations for delayed facial nerve palsy in a patient with Fisher syndrome.

    Science.gov (United States)

    Umekawa, Motoyuki; Hatano, Keiko; Matsumoto, Hideyuki; Shimizu, Takahiro; Hashida, Hideji

    2017-05-27

    The patient was a 47-year-old man who presented with diplopia and gait instability with a gradual onset over the course of three days. Neurological examinations showed ophthalmoplegia, diminished tendon reflexes, and truncal ataxia. Tests for anti-GQ1b antibodies and several other antibodies to ganglioside complex were positive. We made a diagnosis of Fisher syndrome. After administration of intravenous immunoglobulin, the patient's symptoms gradually improved. However, bilateral facial palsy appeared during the recovery phase. Brain MRI showed intensive contrast enhancement of bilateral facial nerves. During the onset phase of facial palsy, the amplitude of the compound muscle action potential (CMAP) in the facial nerves was preserved. During the peak phase, the facial CMAP amplitude was within the lower limit of normal values, or mildly decreased. During the recovery phase, the CMAP amplitude was normalized, and the R1 and R2 responses of the blink reflex were prolonged. The delayed facial nerve palsy improved spontaneously, and the enhancement on brain MRI disappeared. Serial neurophysiological and neuroradiological examinations suggested that the main lesions existed in the proximal part of the facial nerves and the mild lesions existed in the facial nerve terminals, probably due to reversible conduction failure.

  12. [Feasibility and limits of clinical neurophysiology with regard to the objective evaluation of neurological consequences following accidents].

    Science.gov (United States)

    Zipper, Stephan G

    2014-09-01

    It is not unusual for a neurological expert to have problems defining the precise anatomical location and the required objective proof of damage, especially if the medical history and the neurological report released by the clinic prove inadequate in terms of providing a reliable assessment. This may well result from somatoform disorders, dissociation, aggravation and simulation, as well as dissimulation and complex organic diagnostic findings. A range of standardised neurophysiologic procedures is available for the objective measuring of motor, vegetative and sensory systems; a brief summary of the most frequent occurrences is given here, along with their significance for appraising damage resulting from an accident. Target groups primarily include surgeons, orthopaedists, lawyers and insurance specialists. Structural improvements and measures to integrate immigrant doctors is essential.

  13. The crossroads of anxiety: distinct neurophysiological maps for different symptomatic groups

    Directory of Open Access Journals (Sweden)

    Gerez M

    2016-01-01

    Full Text Available Montserrat Gerez,1–3 Enrique Suárez,2,3 Carlos Serrano,2,3 Lauro Castanedo,2 Armando Tello1,3 1Departamento de Neurofisiología Clínica, Hospital Español de México, Mexico City, Mexico; 2Departamento de Psiquiatría, Hospital Español de México, Mexico City, Mexico; 3Unidad de Postgrado, Universidad Nacional Autónoma de México, Mexico City, Mexico Background: Despite the devastating impact of anxiety disorders (ADs worldwide, long-lasting debates on causes and remedies have not solved the clinician’s puzzle: who should be treated and how? Psychiatric classifications conceptualize ADs as distinct entities, with strong support from neuroscience fields. Yet, comorbidity and pharmacological response suggest a single “serotonin dysfunction” dimension. Whether AD is one or several disorders goes beyond academic quarrels, and the distinction has therapeutic relevance. Addressing the underlying dysfunctions should improve treatment response. By its own nature, neurophysiology can be the best tool to address dysfunctional processes.Purpose: To search for neurophysiological dysfunctions and differences among panic disorder (PD, agoraphobia-social-specific phobia, obsessive–compulsive disorder (OCD and generalized anxiety disorder.Methods: A sample population of 192 unmedicated patients and 30 aged-matched controls partook in this study. Hypothesis-related neurophysiological variables were combined into ten independent factors: 1 dysrhythmic patterns, 2 delta, 3 theta, 4 alpha, 5 beta (whole-head absolute power z-scores, 6 event-related potential (ERP combined latency, 7 ERP combined amplitude (z-scores, 8 magnitude, 9 site, and 10 site of hyperactive networks. Combining single variables into representative factors was necessary because, as in all real-life phenomena, the complexity of interactive processes cannot be addressed through single variables and the multiplicity of potentially implicated variables would demand an extremely large

  14. Scientific explanations in Greek upper secondary physics textbooks

    Science.gov (United States)

    Velentzas, Athanasios; Halkia, Krystallia

    2018-01-01

    In this study, an analysis of the structure of scientific explanations included in physics textbooks of upper secondary schools in Greece was completed. In scientific explanations for specific phenomena found in the sample textbooks, the explanandum is a logical consequence of the explanans, which in all cases include at least one scientific law (and/or principle, model or rule) previously presented, as well as statements concerning a specific case or specific conditions. The same structure is also followed in most of the cases in which the textbook authors explain regularities (i.e. laws, rules) as consequences of one or more general law or principle of physics. Finally, a number of the physics laws and principles presented in textbooks are not deduced as consequences from other, more general laws, but they are formulated axiomatically or inductively derived and the authors argue for their validity. Since, as it was found, the scientific explanations presented in the textbooks used in the study have similar structures to the explanations in internationally known textbooks, the findings of the present work may be of interest not only to science educators in Greece, but also to the community of science educators in other countries.

  15. The Duration of Auditory Sensory Memory for Vowel Processing: Neurophysiological and Behavioral Measures

    OpenAIRE

    Yan H. Yu; Valerie L. Shafer; Elyse S. Sussman

    2018-01-01

    Speech perception behavioral research suggests that rates of sensory memory decay are dependent on stimulus properties at more than one level (e.g., acoustic level, phonemic level). The neurophysiology of sensory memory decay rate has rarely been examined in the context of speech processing. In a lexical tone study, we showed that long-term memory representation of lexical tone slows the decay rate of sensory memory for these tones. Here, we tested the hypothesis that long-term memory represe...

  16. Neurophysiological findings in vibration-exposed male workers.

    Science.gov (United States)

    Strömberg, T; Dahlin, L B; Rosén, I; Lundborg, G

    1999-04-01

    Fractionated nerve conduction, vibrotactile sense, and temperature thresholds were studied in 73 symptomatic vibration-exposed male workers. Three symptomatic groups were distinguished: patients with isolated sensorineural symptoms; with isolated vasospastic problems; and with both. Clinical carpal tunnel syndrome occurred in 14 patients and abnormal cold intolerance (without blanching of the fingers) in 23. In the group as a whole, nerve conduction studies were abnormal in the median nerve but not in the ulnar nerve and vibration perception and temperature thresholds were impaired. Of the three symptomatic groups, patients with isolated sensorineural symptoms differed from controls. No differences were seen between patients with and without clinical carpal tunnel syndrome. With severe sensorineural symptoms the vibration perception thresholds, but not the values of the nerve conduction studies, were further impaired. The results indicated two injuries that are easily confused: one at receptor level in the fingertips and one in the carpal tunnel. Careful clinical assessment, neurophysiological testing, and examination of vibrotactile sense are required before carpal tunnel release should be considered in these patients.

  17. Explanation for the Mystical Practice III.

    Directory of Open Access Journals (Sweden)

    Květoslav Minařík

    2016-11-01

    Full Text Available Concentration on feet and legs as a whole, with a special focus on their flesh, has an effect on the development of the intellect and deepening of the sensory discernment, because right here, in the legs, in the flesh of the body, the basis of the inner life is situated. The same concentration with a special focus on their bones – and in particular to the bones of knees – eliminates the instability of the usual attention; it is used to stabilize the entire inner life. The current article is a continuation of Explanation for the Mystical Practice I. and Explanation for the Mystical Practice II., published in the previous editions of Spirituality Studies.

  18. Intraoperative Neurophysiological Monitoring for Endoscopic Endonasal Approaches to the Skull Base: A Technical Guide

    Directory of Open Access Journals (Sweden)

    Harminder Singh

    2016-01-01

    Full Text Available Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the functional integrity of at risk nervous system structures, including the cerebral cortex, brainstem, cranial nerves, corticospinal tract, corticobulbar tract, and the thalamocortical somatosensory system during endonasal surgery of the skull base. The modalities employed include electroencephalography, somatosensory evoked potentials, free-running and electrically triggered electromyography, transcranial electric motor evoked potentials, and auditory evoked potentials. Methodological considerations as well as benefits and limitations are discussed. The authors argue that, while individual modalities have their limitations, multimodality neuromonitoring provides a real-time, comprehensive assessment of nervous system function and allows for safer, more aggressive management of skull base tumors via the endonasal route.

  19. DEMAND FOR AND SUPPLY OF MARK-UP AND PLS FUNDS IN ISLAMIC BANKING: SOME ALTERNATIVE EXPLANATIONS

    OpenAIRE

    KHAN, TARIQULLAH

    1995-01-01

    Profit and loss-sharing (PLS) and bai’ al murabahah lil amir bil shira (mark-up) are the two parent principles of Islamic financing. The use of PLS is limited and that of mark-up overwhelming in the operations of the Islamic banks. Several studies provide different explanations for this phenomenon. The dominant among these is the moral hazard hypothesis. Some alternative explanations are given in the present paper. The discussion is based on both demand (user of funds) and supply (bank) side ...

  20. Ultimate and proximate explanations of strong reciprocity.

    Science.gov (United States)

    Vromen, Jack

    2017-08-23

    Strong reciprocity (SR) has recently been subject to heated debate. In this debate, the "West camp" (West et al. in Evol Hum Behav 32(4):231-262, 2011), which is critical of the case for SR, and the "Laland camp" (Laland et al. in Science, 334(6062):1512-1516, 2011, Biol Philos 28(5):719-745, 2013), which is sympathetic to the case of SR, seem to take diametrically opposed positions. The West camp criticizes advocates of SR for conflating proximate and ultimate causation. SR is said to be a proximate mechanism that is put forward by its advocates as an ultimate explanation of human cooperation. The West camp thus accuses advocates of SR for not heeding Mayr's original distinction between ultimate and proximate causation. The Laland camp praises advocates of SR for revising Mayr's distinction. Advocates of SR are said to replace Mayr's uni-directional view on the relation between ultimate and proximate causes by the bi-directional one of reciprocal causation. The paper argues that both the West camp and the Laland camp misrepresent what advocates of SR are up to. The West camp is right that SR is a proximate cause of human cooperation. But rather than putting forward SR as an ultimate explanation, as the West camp argues, advocates of SR believe that SR itself is in need of ultimate explanation. Advocates of SR tend to take gene-culture co-evolutionary theory as the correct meta-theoretical framework for advancing ultimate explanations of SR. Appearances notwithstanding, gene-culture coevolutionary theory does not imply Laland et al.'s notion of reciprocal causation. "Reciprocal causation" suggests that proximate and ultimate causes interact simultaneously, while advocates of SR assume that they interact sequentially. I end by arguing that the best way to understand the debate is by disambiguating Mayr's ultimate-proximate distinction. I propose to reserve "ultimate" and "proximate" for different sorts of explanations, and to use other terms for distinguishing

  1. Postural control in children with Cerebral Palsy during reaching : assessment of two therapies based on neurophysiological principles

    NARCIS (Netherlands)

    Heide, Jolanda Catharina van der

    2005-01-01

    Dysfunctional postural control is one of the key problems in children with CP. Knowledge on the neurophysiological organisation and development of postural adjustments in children with CP is lacking. The aim of this thesis is therefore to increase our insight in postural problems of children with CR

  2. Neurophysiological model of tinnitus: dependence of the minimal masking level on treatment outcome.

    Science.gov (United States)

    Jastreboff, P J; Hazell, J W; Graham, R L

    1994-11-01

    Validity of the neurophysiological model of tinnitus (Jastreboff, 1990), outlined in this paper, was tested on data from multicenter trial of tinnitus masking (Hazell et al., 1985). Minimal masking level, intensity match of tinnitus, and the threshold of hearing have been evaluated on a total of 382 patients before and after 6 months of treatment with maskers, hearing aids, or combination devices. The data has been divided into categories depending on treatment outcome and type of approach used. Results of analysis revealed that: i) the psychoacoustical description of tinnitus does not possess a predictive value for the outcome of the treatment; ii) minimal masking level changed significantly depending on the treatment outcome, decreasing on average by 5.3 dB in patients reporting improvement, and increasing by 4.9 dB in those whose tinnitus remained the same or worsened; iii) 73.9% of patients reporting improvement had their minimal masking level decreased as compared with 50.5% for patients not showing improvement, which is at the level of random change; iv) the type of device used has no significant impact on the treatment outcome and minimal masking level change; v) intensity match and threshold of hearing did not exhibit any significant changes which can be related to treatment outcome. These results are fully consistent with the neurophysiological interpretation of mechanisms involved in the phenomenon of tinnitus and its alleviation.

  3. Explanations and expectations

    DEFF Research Database (Denmark)

    Järvinen, Margaretha; Ravn, Signe

    2015-01-01

    drug use ‘aetiologies’ drawn upon by the interviewees. These cover childhood experiences, self-medication, the influence of friends and cannabis use as a specific lifestyle. A central argument of the article is that these explanations not only concern the past but also point towards the future......This article analyses how young people enrolled in drug addiction treatment in Copenhagen, Denmark, explain their cannabis careers and how they view their possibilities for quitting drug use again. Inspired by Mead and narrative studies of health and illness, the article identifies four different...

  4. Mind the gap! Automated concept map feedback supports students in writing cohesive explanations.

    Science.gov (United States)

    Lachner, Andreas; Burkhart, Christian; Nückles, Matthias

    2017-03-01

    Many students are challenged with the demand of writing cohesive explanations. To support students in writing cohesive explanations, we developed a computer-based feedback tool that visualizes cohesion deficits of students' explanations in a concept map. We conducted three studies to investigate the effectiveness of such feedback as well as the underlying cognitive processes. In Study 1, we found that the concept map helped students identify potential cohesion gaps in their drafts and plan remedial revisions. In Study 2, students with concept map feedback conducted revisions that resulted in more locally and globally cohesive, and also more comprehensible, explanations than the explanations of students who revised without concept map feedback. In Study 3, we replicated the findings of Study 2 by and large. More importantly, students who had received concept map feedback on a training explanation 1 week later wrote a transfer explanation without feedback that was more cohesive than the explanation of students who had received no feedback on their training explanation. The automated concept map feedback appears to particularly support the evaluation phase of the revision process. Furthermore, the feedback enabled novice writers to acquire sustainable skills in writing cohesive explanations. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. The Diboson Excess: Experimental Situation and Classification of Explanations; A Les Houches Pre-Proceeding

    CERN Document Server

    Brehmer, Johann; Cacciapaglia, Giacomo; Carmona, Adrian; Chivukula, R.Sekhar; Delgado, Antonio; Goertz, Florian; Hewett, JoAnne L.; Katz, Andrey; Kopp, Joachim; Lane, Kenneth; Martin, Adam; Mohan, Kirtimaan; Morse, David M.; Nardecchia, Marco; No, Jose Miguel; Oliveira, Alexandra; Pollard, Chris; Quiros, Mariano; Rizzo, Thomas G.; Santiago, Jose; Sanz, Veronica; Simmons, Elizabeth H.; Tattersall, Jamie

    2015-01-01

    We examine the `diboson' excess at $\\sim 2$ TeV seen by the LHC experiments in various channels. We provide a comparison of the excess significances as a function of the mass of the tentative resonance and give the signal cross sections needed to explain the excesses. We also present a survey of available theoretical explanations of the resonance, classified in three main approaches. Beyond that, we discuss methods to verify the anomaly, determining the major properties of the various surpluses and exploring how different models can be discriminated. Finally, we give a tabular summary of the numerous explanations, presenting their main phenomenological features.

  6. Propofol (2,6-diisopropylphenol) is an applicable immersion anesthetic in the axolotl with potential uses in hemodynamic and neurophysiological experiments

    DEFF Research Database (Denmark)

    Thygesen, Mathias; Rasmussen, Mikkel Mylius; Madsen, Jesper Guldsmed

    2017-01-01

    The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some...... neurophysiological experiments this is not desirable; therefore we tested propofol as an alternative anesthetic in the axolotl. We evaluated benzocaine, MS-222, and propofol's cardiovascular effects, effects on action potential propagation in the spinal cord, and gross limb regenerative effects. We found...... that propofol is applicable as a general anesthetic in the axolotl allowing for neurophysiological experiments and yielding a stable anesthesia with significantly less cardiovascular effect than both benzocaine and MS-222. Additionally, propofol did not affect gross limb regeneration. In conclusion we suggest...

  7. Propofol (2,6-diisopropylphenol) is an applicable immersion anesthetic in the axolotl with potential uses in hemodynamic and neurophysiological experiments

    DEFF Research Database (Denmark)

    Thygesen, Mathias; Rasmussen, Mikkel Mylius; Madsen, Jesper Guldsmed

    2017-01-01

    The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some neurophysiologi......The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some...... neurophysiological experiments this is not desirable; therefore we tested propofol as an alternative anesthetic in the axolotl. We evaluated benzocaine, MS-222, and propofol's cardiovascular effects, effects on action potential propagation in the spinal cord, and gross limb regenerative effects. We found...

  8. Mind and Meaning: Piaget and Vygotsky on Causal Explanation.

    Science.gov (United States)

    Beilin, Harry

    1996-01-01

    Piaget's theory has been characterized as descriptive and not explanatory, not qualifying as causal explanation. Piaget was consistent in showing how his theory was both explanatory and causal. Vygotsky also endorsed causal-genetic explanation but, on the basis of knowledge of only Piaget's earliest works, he claimed that Piaget's theory was not…

  9. Particle physics explanations for ultra-high energy cosmic ray events

    Indian Academy of Sciences (India)

    this talk I briefly summarize several proposed particle physics explanations: a breakdown ... as primaries, and magnetic monopoles with mass below 1010 GeV as primaries. .... these monopoles would be the ultimate test of this explanation.

  10. Tactile and non-tactile sensory paradigms for fMRI and neurophysiologic studies in rodents

    OpenAIRE

    Sanganahalli, Basavaraju G.; Bailey, Christopher J.; Herman, Peter; Hyder, Fahmeed

    2009-01-01

    Functional magnetic resonance imaging (fMRI) has become a popular functional imaging tool for human studies. Future diagnostic use of fMRI depends, however, on a suitable neurophysiologic interpretation of the blood oxygenation level dependent (BOLD) signal change. This particular goal is best achieved in animal models primarily due to the invasive nature of other methods used and/or pharmacological agents applied to probe different nuances of neuronal (and glial) activity coupled to the BOLD...

  11. Supernatural Explanations: Science or Not?

    Science.gov (United States)

    Eastwell, Peter

    2011-01-01

    Contrary to the advice of supposedly authoritative sources, the a priori exclusion of supernatural explanations or claims from scientific scrutiny is not appropriate. This paper shows how supernatural hypotheses or claims should be treated by science and, in the process, differentiates scientific and non-scientific hypotheses or claims.…

  12. Coleridge: a computer tool for assisting musical reflection and self-explanation

    Directory of Open Access Journals (Sweden)

    John Cook

    1998-12-01

    Full Text Available Since the mid-1980s, there has been a movement away from knowledge supplied by the teacher and towards talking, reflecting and explaining as ways to learn. An example of this change in focus is provided by the self-explanation work of Chi et al (1994 who describe an approach to talking science rather than hearing science. According to Chi and coworkers, generating explanations to oneself (self-explanations facilitates the integration of new information into existing knowledge. Reflecting about one's own learning is the same as thinking about learning or metacognition. Metacognition can be defined as the understanding of knowledge, an understanding that can be reflected in either effective use or overt description of the knowledge in question (Brown, 1987. This definition of metacognition requires of a learner both internalized thinking about learning (that is, reflection, and externalized communication, through language or action, that indicates an understanding of knowledge (that is, a self-explanation. In the work described in this paper the overall pedagogical goal is to encourage creative reflection in learners. Creative reflection is defined as the ability of a learner to imagine musical opportunities in novel situations, and then to make accurate predictions (verbally about these opportunities. To succeed at creative reflection there should be a correspondence between what a learner predicts will happen and what actually happens. An example would be a learner first writing a musical phrase using musical notation, then predicting verbally how that phrase will sound, playing the phrase back on a piano, and finally evaluating if the prediction was accurate or not. Very little work has been done on how computers can be used to support talking, reflecting and explaining in the creative subject-area of musical composition. The rest of this paper addresses this issue.

  13. Self-Explanation, An Instructional Strategy to Foster Clinical Reasoning in Medical Students

    Directory of Open Access Journals (Sweden)

    Martine Chamberland

    2015-12-01

    Full Text Available Clinical reasoning is a critical and complex skill that medical students have to develop in the course of their training. Although research on medical expertise has successfully examined the different components of that skill, designing educational interventions that support the development of clinical reasoning in students remains a challenge for medical educators. The theory of medical expertise describes how students׳ medical knowledge develops and is progressively restructured during their training and in particular through clinical exposure to patient problems. Instructional strategies to foster students’ learning from practice with clinical cases are scarce. This article describes the use of self-explanation as such a strategy. Self-explanation is an active learning technique of proven effectiveness in other domains which consists of having students explaining to themselves information on to-be-learned materials. The mechanisms through which self-explanation fosters learning are described. Self-explanation promotes knowledge development and revision of mental representations through elaboration on new information, organisation and integration of new knowledge into existing cognitive structures and monitoring of the learning process. Subsequently, the article shows how self-explanation has recently been investigated in medicine as an instructional strategy to support students׳ clinical reasoning. Available studies have demonstrated that students׳ diagnostic performance improves when they use self-explanation while solving clinical problems of a less familiar clinical topic. Unfamiliarity seems to trigger more self-explanations and to stimulate students to reactivate relevant biomedical knowledge, which could lead to the development of more coherent representations of diseases. The benefit of students׳ self-explanation is increased when it is combined with listening to residents׳ self-explanation examples and with prompts. The

  14. Making context explicit for explanation and incremental knowledge acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Brezillon, P. [Univ. Paris (France)

    1996-12-31

    Intelligent systems may be improved by making context explicit in problem solving. This is a lesson drawn from a study of the reasons why a number of knowledge-based systems (KBSs) failed. We discuss the interest to make context explicit in explanation generation and incremental knowledge acquisition, two important aspects of intelligent systems that aim to cooperate with users. We show how context can be used to better explain and incrementally acquire knowledge. The advantages of using context in explanation and incremental knowledge acquisition are discussed through SEPIT, an expert system for supporting diagnosis and explanation through simulation of power plants. We point out how the limitations of such systems may be overcome by making context explicit.

  15. Automatic detection of rhythmic and periodic patterns in critical care EEG based on American Clinical Neurophysiology Society (ACNS) standardized terminology.

    Science.gov (United States)

    Fürbass, F; Hartmann, M M; Halford, J J; Koren, J; Herta, J; Gruber, A; Baumgartner, C; Kluge, T

    2015-09-01

    Continuous EEG from critical care patients needs to be evaluated time efficiently to maximize the treatment effect. A computational method will be presented that detects rhythmic and periodic patterns according to the critical care EEG terminology (CCET) of the American Clinical Neurophysiology Society (ACNS). The aim is to show that these detected patterns support EEG experts in writing neurophysiological reports. First of all, three case reports exemplify the evaluation procedure using graphically presented detections. Second, 187 hours of EEG from 10 critical care patients were used in a comparative trial study. For each patient the result of a review session using the EEG and the visualized pattern detections was compared to the original neurophysiology report. In three out of five patients with reported seizures, all seizures were reported correctly. In two patients, several subtle clinical seizures with unclear EEG correlation were missed. Lateralized periodic patterns (LPD) were correctly found in 2/2 patients and EEG slowing was correctly found in 7/9 patients. In 8/10 patients, additional EEG features were found including LPDs, EEG slowing, and seizures. The use of automatic pattern detection will assist in review of EEG and increase efficiency. The implementation of bedside surveillance devices using our detection algorithm appears to be feasible and remains to be confirmed in further multicenter studies. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. Experience and Explanation: Using Videogames to Prepare Students for Formal Instruction in Statistics

    Science.gov (United States)

    Arena, Dylan A.; Schwartz, Daniel L.

    2014-01-01

    Well-designed digital games can deliver powerful experiences that are difficult to provide through traditional instruction, while traditional instruction can deliver formal explanations that are not a natural fit for gameplay. Combined, they can accomplish more than either can alone. An experiment tested this claim using the topic of statistics,…

  17. Functional MRI, DTI and neurophysiology in horizontal gaze palsy with progressive scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Haller, Sven; Wetzel, Stephan G. [University Hospital Basel, Institute of Radiology, Department of Neuroradiology, Basel (Switzerland); Luetschg, Juerg [University Children' s Hospital (UKBB), Basel (Switzerland)

    2008-05-15

    Horizontal gaze palsy with progressive scoliosis (HGPPS) is an autosomal recessive disease due to a mutation in the ROBO3 gene. This rare disease is of particular interest because the absence, or at least reduction, of crossing of the ascending lemniscal and descending corticospinal tracts in the medulla predicts abnormal ipsilateral sensory and motor systems. We evaluated the use of functional magnetic resonance imaging (fMRI) for the first time in this disease and compared it to diffusion tensor imaging (DTI) tractography and neurophysiological findings in the same patient with genetically confirmed ROBO3 mutation. As expected, motor fMRI, somatosensory evoked potentials (SSEP) and motor evoked potentials (MEP) were dominantly ipsilateral to the stimulation side. DTI tractography revealed ipsilateral ascending and descending connectivity in the brainstem yet normal interhemispheric connections in the corpus callosum. Auditory fMRI revealed bilateral auditory activation to monaural left-sided auditory stimulation. No significant cortical activation was observed after monaural right-sided stimulation, a hearing defect having been excluded. Prosaccades fMRI showed no activations in the eye-movement network. Motor fMRI confirmed the established findings of DTI and neurophysiology in the same patient. In suspected HGPPS, any technique appears appropriate for further investigation. Auditory fMRI suggests that a monaural auditory system with bilateral auditory activations might be a physiological advantage as compared to a binaural yet only unilateral auditory system, in analogy to anisometropic amblyopia. Moving-head fMRI studies in the future might show whether the compensatory head movements instead of normal eye movements activate the eye-movement network. (orig.)

  18. Functional MRI, DTI and neurophysiology in horizontal gaze palsy with progressive scoliosis

    International Nuclear Information System (INIS)

    Haller, Sven; Wetzel, Stephan G.; Luetschg, Juerg

    2008-01-01

    Horizontal gaze palsy with progressive scoliosis (HGPPS) is an autosomal recessive disease due to a mutation in the ROBO3 gene. This rare disease is of particular interest because the absence, or at least reduction, of crossing of the ascending lemniscal and descending corticospinal tracts in the medulla predicts abnormal ipsilateral sensory and motor systems. We evaluated the use of functional magnetic resonance imaging (fMRI) for the first time in this disease and compared it to diffusion tensor imaging (DTI) tractography and neurophysiological findings in the same patient with genetically confirmed ROBO3 mutation. As expected, motor fMRI, somatosensory evoked potentials (SSEP) and motor evoked potentials (MEP) were dominantly ipsilateral to the stimulation side. DTI tractography revealed ipsilateral ascending and descending connectivity in the brainstem yet normal interhemispheric connections in the corpus callosum. Auditory fMRI revealed bilateral auditory activation to monaural left-sided auditory stimulation. No significant cortical activation was observed after monaural right-sided stimulation, a hearing defect having been excluded. Prosaccades fMRI showed no activations in the eye-movement network. Motor fMRI confirmed the established findings of DTI and neurophysiology in the same patient. In suspected HGPPS, any technique appears appropriate for further investigation. Auditory fMRI suggests that a monaural auditory system with bilateral auditory activations might be a physiological advantage as compared to a binaural yet only unilateral auditory system, in analogy to anisometropic amblyopia. Moving-head fMRI studies in the future might show whether the compensatory head movements instead of normal eye movements activate the eye-movement network. (orig.)

  19. Functional MRI, DTI and neurophysiology in horizontal gaze palsy with progressive scoliosis.

    Science.gov (United States)

    Haller, Sven; Wetzel, Stephan G; Lütschg, Jürg

    2008-05-01

    Horizontal gaze palsy with progressive scoliosis (HGPPS) is an autosomal recessive disease due to a mutation in the ROBO3 gene. This rare disease is of particular interest because the absence, or at least reduction, of crossing of the ascending lemniscal and descending corticospinal tracts in the medulla predicts abnormal ipsilateral sensory and motor systems. We evaluated the use of functional magnetic resonance imaging (fMRI) for the first time in this disease and compared it to diffusion tensor imaging (DTI) tractography and neurophysiological findings in the same patient with genetically confirmed ROBO3 mutation. As expected, motor fMRI, somatosensory evoked potentials (SSEP) and motor evoked potentials (MEP) were dominantly ipsilateral to the stimulation side. DTI tractography revealed ipsilateral ascending and descending connectivity in the brainstem yet normal interhemispheric connections in the corpus callosum. Auditory fMRI revealed bilateral auditory activation to monaural left-sided auditory stimulation. No significant cortical activation was observed after monaural right-sided stimulation, a hearing defect having been excluded. Prosaccades fMRI showed no activations in the eye-movement network. Motor fMRI confirmed the established findings of DTI and neurophysiology in the same patient. In suspected HGPPS, any technique appears appropriate for further investigation. Auditory fMRI suggests that a monaural auditory system with bilateral auditory activations might be a physiological advantage as compared to a binaural yet only unilateral auditory system, in analogy to anisometropic amblyopia. Moving-head fMRI studies in the future might show whether the compensatory head movements instead of normal eye movements activate the eye-movement network.

  20. Perils of intraoperative neurophysiological monitoring: analysis of "false-negative" results in spine surgeries.

    Science.gov (United States)

    Tamkus, Arvydas A; Rice, Kent S; McCaffrey, Michael T

    2018-02-01

    Although some authors have published case reports describing false negatives in intraoperative neurophysiological monitoring (IONM), a systematic review of causes of false-negative IONM results is lacking. The objective of this study was to analyze false-negative IONM findings in spine surgery. This is a retrospective cohort analysis. A cohort of 109 patients with new postoperative neurologic deficits was analyzed for possible false-negative IONM reporting. The causes of false-negative IONM reporting were determined. From a cohort of 62,038 monitored spine surgeries, 109 consecutive patients with new postoperative neurologic deficits were reviewed for IONM alarms. Intraoperative neurophysiological monitoring alarms occurred in 87 of 109 surgeries. Nineteen patients with new postoperative neurologic deficits did not have an IONM alarm and surgeons were not warned. In addition, three patients had no interpretable IONM baseline data and no alarms were possible for the duration of the surgery. Therefore, 22 patients were included in the study. The absence of IONM alarms during these 22 surgeries had different origins: "true" false negatives where no waveform changes meeting the alarm criteria occurred despite the appropriate IONM (7); a postoperative development of a deficit (6); failure to monitor the pathway, which became injured (5); the absence of interpretable IONM baseline data which precluded any alarm (3); and technical IONM application issues (1). Overall, the rate of IONM method failing to predict the patient's outcome was very low (0.04%, 22/62,038). Minimizing false negatives requires the application of a proper IONM technique with the limitations of each modality considered in their selection and interpretation. Multimodality IONM provides the most inclusive information, and although it might be impractical to monitor every neural structure that can be at risk, a thorough preoperative consideration of available IONM modalities is important. Delayed

  1. A Critical Analysis of the Established Explanations about the Nature of Ecotourism

    Directory of Open Access Journals (Sweden)

    Nazmiye Erdoğan

    2012-12-01

    Full Text Available This qualitative study questions the prevailing explanations about the nature of ecotourism. The major aims of the study are (a to point out that the widespread notions and theoretical attributions about the character of ecotourism should be reconsidered and (b to express the need for critical questioning and design in qualitative and quantitative academic studies in social, management, administrative and tourism sciences. The article explains, first, the basic rationale for legitimizing, market building, supporting, sustaining and expanding the capitalist market, including ecotourism practices, and connects the concept of environment with economy, and inclusion of tourism and ecotourism in sustainable development. Then, it discusses the nature of dominant explanations of ecotourism. The study concludes that widespread explanations of the nature, structure, activity and outcome of ecotourism rarely match the nature of daily ecotourism practices. Instead, they generally create, employ and sustain functional myths about industrial practices, relations, causes, effects and outcomes of ecotourism. They provide strategically prescriptive and normative ethics and principles that are mostly unattainable. They consciously or inadvertently ignore the fact that the notion of ecotourism is deeply embedded in the logics of ideological normalisation of corporate activities, commodity circulation, technological end-product distribution and use, and global governance of the economic, political and cultural market conditions.

  2. Investigating the origins of political views: biases in explanation predict conservative attitudes in children and adults.

    Science.gov (United States)

    Hussak, Larisa J; Cimpian, Andrei

    2018-05-01

    We tested the hypothesis that political attitudes are influenced by an information-processing factor - namely, a bias in the content of everyday explanations. Because many societal phenomena are enormously complex, people's understanding of them often relies on heuristic shortcuts. For instance, when generating explanations for such phenomena (e.g., why does this group have low status?), people often rely on facts that they can retrieve easily from memory - facts that are skewed toward inherent or intrinsic features (e.g., this group is unintelligent). We hypothesized that this bias in the content of heuristic explanations leads to a tendency to (1) view socioeconomic stratification as acceptable and (2) prefer current societal arrangements to alternative ones, two hallmarks of conservative ideology. Moreover, since the inherence bias in explanation is present across development, we expected it to shape children's proto-political judgments as well. Three studies with adults and 4- to 8-year-old children (N = 784) provided support for these predictions: Not only did individual differences in reliance on inherent explanations uniquely predict endorsement of conservative views (particularly the stratification-supporting component; Study 1), but manipulations of this explanatory bias also had downstream consequences for political attitudes in both children and adults (Studies 2 and 3). This work contributes to our understanding of the origins of political attitudes. © 2017 John Wiley & Sons Ltd.

  3. Tutorial dialogues and gist explanations of genetic breast cancer risk.

    Science.gov (United States)

    Widmer, Colin L; Wolfe, Christopher R; Reyna, Valerie F; Cedillos-Whynott, Elizabeth M; Brust-Renck, Priscila G; Weil, Audrey M

    2015-09-01

    The intelligent tutoring system (ITS) BRCA Gist is a Web-based tutor developed using the Shareable Knowledge Objects (SKO) platform that uses latent semantic analysis to engage women in natural-language dialogues to teach about breast cancer risk. BRCA Gist appears to be the first ITS designed to assist patients' health decision making. Two studies provide fine-grained analyses of the verbal interactions between BRCA Gist and women responding to five questions pertaining to breast cancer and genetic risk. We examined how "gist explanations" generated by participants during natural-language dialogues related to outcomes. Using reliable rubrics, scripts of the participants' verbal interactions with BRCA Gist were rated for content and for the appropriateness of the tutor's responses. Human researchers' scores for the content covered by the participants were strongly correlated with the coverage scores generated by BRCA Gist, indicating that BRCA Gist accurately assesses the extent to which people respond appropriately. In Study 1, participants' performance during the dialogues was consistently associated with learning outcomes about breast cancer risk. Study 2 was a field study with a more diverse population. Participants with an undergraduate degree or less education who were randomly assigned to BRCA Gist scored higher on tests of knowledge than those assigned to the National Cancer Institute website or than a control group. We replicated findings that the more expected content that participants included in their gist explanations, the better they performed on outcome measures. As fuzzy-trace theory suggests, encouraging people to develop and elaborate upon gist explanations appears to improve learning, comprehension, and decision making.

  4. Mechanisms of cold fusion: comprehensive explanations by the Nattoh model

    International Nuclear Information System (INIS)

    Matsumoto, Takaaki

    1995-01-01

    The phenomena of cold fusion seem to be very complicated; inconsistent data between the production rates of heat, neutrons, tritiums and heliums. Our thoughts need to drastically change in order to appropriately understand the mechanisms of cold fusion. Here, a review is described for the Nattoh model, that has been developed extensively to provide comprehensive explanations for the mechanisms of cold fusion. Important experimental findings that prove the model are described. Furthermore several subjects including impacts on other fields are also discussed. (author)

  5. Testing the Transivity Explanation of the Allais Paradox

    DEFF Research Database (Denmark)

    Groes, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte

    1999-01-01

    This paper uses a two-dimensional version of a standard common consequence experiment to test the intransitivity explanation of Allais-paradox-type violations of expected utility theory. We compare the common consequence effect of two choice problems differing only with respect to whether...... intransitivity as an explanation of the Allais Paradox. The question whether violations of expected utility are mainly due to intransitivity or to violation of independence is important since it is exactly on this issue the main new decision theories differ...

  6. Is there a place for psychology in the framework of rational choice theory?

    Directory of Open Access Journals (Sweden)

    Mladenović Ivan

    2010-01-01

    Full Text Available This paper aims to discuss psychological aspect of rational choice theory. The standard version of rational choice rests on a kind of psychology, since it operates with mental states. In standard davidsonian version it is claimed that we explain rational actions by stating proper desires and beliefs that caused the action. We will explore two challenges to the standard version that might be called cultural and naturalistic versions of rational choice. Satz and Ferejohn (1994 challenged standard version by stating that we can provide rational-choice explanations without relying too much on psychological assumptions. They argued in favor of moderate externalism, which should replace thin desire-belief model with thick structuralist conception. According to their model moderate externalism is compatible with realism about psychological states, while at the same time those states need not figure in the best rational choice explanations of actions. The focus of rational choice explanations therefore shifts to non-individual and non-psychological entities, such as firms in explaining economic behavior, parties in explaining functioning of democracy, etc. Although there is a place for psychological states within a moderate externalism, those states are not causally relevant. On Pettit’s account desires and beliefs figure in rational choice explanations merely as “standby causes”. They explain resilience of certain behavior, not its actual cause. Quite contrary to standard rational choice theory, the programming model (Pettit, 2002 defines the neurophysiological level as more basic in explaining behavior. This means that higher-level psychological states are causally relevant for certain behavior only if certain lower-level neurophysiological producer obtains. In this paper standard rational choice theory will be defended against culturalist and naturalist criticism.

  7. Evidence for the late MMN as a neurophysiological endophenotype for dyslexia.

    Directory of Open Access Journals (Sweden)

    Nina Neuhoff

    Full Text Available Dyslexia affects 5-10% of school-aged children and is therefore one of the most common learning disorders. Research on auditory event related potentials (AERP, particularly the mismatch negativity (MMN component, has revealed anomalies in individuals with dyslexia to speech stimuli. Furthermore, candidate genes for this disorder were found through molecular genetic studies. A current challenge for dyslexia research is to understand the interaction between molecular genetics and brain function, and to promote the identification of relevant endophenotypes for dyslexia. The present study examines MMN, a neurophysiological correlate of speech perception, and its potential as an endophenotype for dyslexia in three groups of children. The first group of children was clinically diagnosed with dyslexia, whereas the second group of children was comprised of their siblings who had average reading and spelling skills and were therefore "unaffected" despite having a genetic risk for dyslexia. The third group consisted of control children who were not related to the other groups and were also unaffected. In total, 225 children were included in the study. All children showed clear MMN activity to/da/-/ba/contrasts that could be separated into three distinct MMN components. Whilst the first two MMN components did not differentiate the groups, the late MMN component (300-700 ms revealed significant group differences. The mean area of the late MMN was attenuated in both the dyslexic children and their unaffected siblings in comparison to the control children. This finding is indicative of analogous alterations of neurophysiological processes in children with dyslexia and those with a genetic risk for dyslexia, without a manifestation of the disorder. The present results therefore further suggest that the late MMN might be a potential endophenotype for dyslexia.

  8. Neurophysiological correlates of artistic image creation by representatives of artistic professions

    Directory of Open Access Journals (Sweden)

    Dikaya L. A.

    2016-12-01

    Full Text Available The steadily increasing demand for artistic professions brings to the fore the task of studying the phenomenon of art by researching the unique capacity of the human brain to create works of art in different spheres of creative activity. So far, only a few studies have investigated creativity-related brain activity in representatives of the creative professions. The aim of the empirical research was to study the neurophysiological correlates of artistic image creation by representatives of the artistic professions. The participants were 60 right-handed females aged 23-27, divided into three groups— artists (23 people, actors (17 people, and specialists who do not work in an artistic field (20 people. The mono-typing technique was used to model the creative artistic process. EEG signals were recorded in a resting state, and during four stages of the creation of an artistic image (viewing of monotypes, frustration, image creation, and thinking over the details from 21 electrodes set on the scalp according to the International 10-20 System. We analyzed EEG coherence for each functional trial at theta (4.00–8.00 Hz, alpha1 (8.00–10.5 Hz, alpha2 (10.5–13.00 Hz, and beta (13.00– 35.00 Hz frequency bands. For statistical analysis, we used MANOVA and post hoc analysis. We found that the neurophysiological correlates of creating an artistic image are different at different stages of the creative process, and have different features for artists and actors. The actors primarily show dominance of right hemisphere activity, while close interaction of the hemispheres distinguishes the brains of the artists. The differences revealed in brain cortex functioning when artists or actors create an artistic image reflect different strategies of imaginative creative work by representatives of these professions.

  9. Generative Mechanistic Explanation Building in Undergraduate Molecular and Cellular Biology

    Science.gov (United States)

    Southard, Katelyn M.; Espindola, Melissa R.; Zaepfel, Samantha D.; Bolger, Molly S.

    2017-01-01

    When conducting scientific research, experts in molecular and cellular biology (MCB) use specific reasoning strategies to construct mechanistic explanations for the underlying causal features of molecular phenomena. We explored how undergraduate students applied this scientific practice in MCB. Drawing from studies of explanation building among…

  10. Generative mechanistic explanation building in undergraduate molecular and cellular biology

    Science.gov (United States)

    Southard, Katelyn M.; Espindola, Melissa R.; Zaepfel, Samantha D.; Bolger, Molly S.

    2017-09-01

    When conducting scientific research, experts in molecular and cellular biology (MCB) use specific reasoning strategies to construct mechanistic explanations for the underlying causal features of molecular phenomena. We explored how undergraduate students applied this scientific practice in MCB. Drawing from studies of explanation building among scientists, we created and applied a theoretical framework to explore the strategies students use to construct explanations for 'novel' biological phenomena. Specifically, we explored how students navigated the multi-level nature of complex biological systems using generative mechanistic reasoning. Interviews were conducted with introductory and upper-division biology students at a large public university in the United States. Results of qualitative coding revealed key features of students' explanation building. Students used modular thinking to consider the functional subdivisions of the system, which they 'filled in' to varying degrees with mechanistic elements. They also hypothesised the involvement of mechanistic entities and instantiated abstract schema to adapt their explanations to unfamiliar biological contexts. Finally, we explored the flexible thinking that students used to hypothesise the impact of mutations on multi-leveled biological systems. Results revealed a number of ways that students drew mechanistic connections between molecules, functional modules (sets of molecules with an emergent function), cells, tissues, organisms and populations.

  11. The Quality of Explanations for Deviation from Principles of Corporate Governance. An Introduction

    Directory of Open Access Journals (Sweden)

    Izabela Koładkiewicz

    2017-11-01

    Full Text Available Purpose: The purpose of this paper is to summarize studies aiming to define matters related to the quality of explanations found in corporate governance statements published by listed companies. Another important aspect of the conducted analysis is the identification of various dimensions of explanation quality. Methodology: The character of the conducted research is that of an overview of literature devoted to the subject. Apart from scientific articles, it covers European Union regulations, regulations characteristic of countries selected for the analysis (member states of the European Union, and applied solutions aimed at guaranteeing the desired quality of explanations for deviation included in corporate governance statements that are in the centre of attention. Findings: The conducted analysis organizes the current knowledge concerning actions aimed at improving the quality of explanations for deviation from principles of corporate governance. Without a doubt, the primary pillar consists of the level of information and its quality, as found in explanations for shareholders. It is this quality that determines if the shareholder understands the processes occurring in the realm of corporate governance in the company. Research limitations: The conducted analysis should be treated as an introduction to related research issues. It should be stressed that research into explanations provided by companies is still in the process of development, and the number of publications devoted to this topic is still modest. Practical implications: The study fits in the research into the phenomena of the “comply or explain” mechanism as applied in practice, which according of many researchers, continues to be poorly investigated. In terms of the directions for further research, there are promising topics including e.g. identification of factors that may translate into the quality of such statements (e.g. ownership structure, identity of shareholders, the

  12. "Too much medicine": Insights and explanations from economic theory and research.

    Science.gov (United States)

    Hensher, Martin; Tisdell, John; Zimitat, Craig

    2017-03-01

    Increasing attention has been paid in recent years to the problem of "too much medicine", whereby patients receive unnecessary investigations and treatments providing them with little or no benefit, but which expose them to risks of harm. Despite this phenomenon potentially constituting an inefficient use of health care resources, it has received limited direct attention from health economists. This paper considers "too much medicine" as a form of overconsumption, drawing on research from health economics, behavioural economics and ecological economics to identify possible explanations for and drivers of overconsumption. We define overconsumption of health care as a situation in which individuals consume in a way that undermines their own well-being. Extensive health economics research since the 1960s has provided clear evidence that physicians do not act as perfect agents for patients, and there are perverse incentives for them to provide unnecessary services under various circumstances. There is strong evidence of the existence of supplier-induced demand, and of the impact of various forms of financial incentives on clinical practice. The behavioural economics evidence provides rich insights on why clinical practice may depart from an "evidence-based" approach. Moreover, behavioural findings on health professionals' strategies for dealing with uncertainty, and for avoiding potential regret, provide powerful explanations of why overuse and overtreatment may frequently appear to be the "rational" choice in clinical decision-making, even when they cause harm. The ecological economics literature suggests that status or positional competition can, via the principal-agent relationship in health care, provide a further force driving overconsumption. This novel synthesis of economic perspectives suggests important scope for interdisciplinary collaboration; signals potentially important issues for health technology assessment and health technology management policies; and

  13. Gender differences in attitudes toward nuclear power: a multivariate explanation

    International Nuclear Information System (INIS)

    Baxter, R.K.

    1987-01-01

    The purpose of this study was to examine gender differences in attitudes toward nuclear power and to discover what factors account for these differences. The marginality explanation for these differences suggest that women have less-favorable attitudes toward nuclear power because they are less concerned about energy supplies and economic growth and are less convinced of the benefits of nuclear power for society than are men. The irrationality explanation holds that women are less favorable toward nuclear power because they are less knowledgeable about this technology than are men. The lay-rationality explanation argues that people form attitudes toward nuclear power which are consistent with their relevant beliefs, attitudes and values; thus, this explanation suggests that women's unfavorable attitudes toward nuclear power stem from greater concern about environmental protection, exposing society to risk, and lower faith in science and technology. Data for this study were collected via a mail questionnaire administered to a state wide sample of Washington residents (n= 696)

  14. Evaluating Sativex® in Neuropathic Pain Management: A Clinical and Neurophysiological Assessment in Multiple Sclerosis.

    Science.gov (United States)

    Russo, Margherita; Naro, Antonino; Leo, Antonino; Sessa, Edoardo; D'Aleo, Giangaetano; Bramanti, Placido; Calabrò, Rocco Salvatore

    2016-06-01

    The aim of our study was to better investigate the role of Sativex(®) in improving pain in multiple sclerosis (MS) patients by means of either clinical or neurophysiological assessment. Pain is a common symptom of MS, affecting up to 70% of patients. Pain treatment is often unsatisfactory, although emerging drugs (including cannabinoids) are giving encouraging results. Clinical pain assessment in MS is very difficult, and more objective tools are necessary to better quantify this symptom and its potential response to the treatments. We enrolled 20 MS patients (10 with and 10 without neuropathic pain), who underwent a specific clinical (such as visual analog scale) and neurophysiological assessment (by means of laser-evoked potentials and transcranial magnetic stimulation), before and after 4 weeks of Sativex administration. One month of drug administration in MS patients with neuropathic pain successfully reduced pain rating and improved quality of life. Interestingly, such effects were paralleled by an increase of fronto-central γ-band oscillation and of pain-motor integration strength. Our data suggest that Sativex may be effective in improving MS-related neuropathic pain, maybe through its action on specific cortical pathways. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. [The neurodynamic core of consciousness and neural Darwinism].

    Science.gov (United States)

    Ibáñez, A

    In the last decades, the scientific study of consciousness in the scope of the cognitive neurosciences can be considered one of the greatest challenges of contemporary science. The Gerald Edelman theory of consciousness is one of the most promising and controversial perspectives. This theory stands out by its approach to topics usually rejected by other neurophysiologic theories of consciousness, as the case of the neurophysiologic explanation of qualia. The goal of this paper is to review the dynamic core theory of consciousness, presenting the main features of the theory, analyzing the explanation strategies, their empirical extensions, and elaborating some critical considerations about the possibility of the neuroscientific study of qualia. The central and additional theoretical components are analyzed, emphasizing its ontological, restrictive and explanatory assumptions. The properties of conscious phenomena and their cerebral correlates as advanced by the theory are described, and finally its experiments and empirical extensions are examined. The explanatory strategies of the theory are analyzed, based on conceptual isomorphism between the phenomenological properties and the neurophysiological and mathematical measures. Some criticisms could be raised about the limitations of the dynamic core theory, especially regarding its account of the so-called 'hard problem' of consciousness or qualia.

  16. Invisible-hand explanations: From blindness to lack of we-ness

    OpenAIRE

    Dayer-Tieffenbach, Emma

    2013-01-01

    The unintendedness of the phenomenon that is to be explained is a constraint visible in the various applications and clarifications of invisible hand explanations. The article casts doubt on such a requirement and proposes a revised account. To have a role in an invisible hand process it is argued agents may very well act with a view to contributing to the occurrence of the social outcome that is to be explained provided they see what they do as an aggregation of their individual actions rath...

  17. "Ratio via Machina": Three Standards of Mechanistic Explanation in Sociology

    Science.gov (United States)

    Aviles, Natalie B.; Reed, Isaac Ariail

    2017-01-01

    Recently, sociologists have expended much effort in attempts to define social mechanisms. We intervene in these debates by proposing that sociologists in fact have a choice to make between three standards of what constitutes a good mechanistic explanation: substantial, formal, and metaphorical mechanistic explanation. All three standards are…

  18. Is appreciation of written education about pain neurophysiology related to changes in illness perceptions and health status in patients with fibromyalgia?

    Science.gov (United States)

    van Ittersum, M W; van Wilgen, C P; Groothoff, J W; van der Schans, C P

    2011-11-01

    To investigate the appreciation of written education about pain neurophysiology in patients with fibromyalgia (FM) and its effects on illness perceptions and perceived health status. A booklet explaining pain neurophysiology was sent to participants with FM. Appreciation was assessed with 10 questions addressing relevance (0-30) and reassurance (0-30). Illness perceptions, catastrophizing and health status were measured with the Revised Illness Perception Questionnaire (IPQ-R), the Pain Catastrophizing Scale (PCS) and the Fibromyalgia Impact Questionnaire (FIQ) at baseline (T0), after a 2-week control period (T1) and 6 weeks after the intervention (T2). Forty-one patients participated. Mean (SD) scores for relevance and reassurance were 21.6 (5.6) and 18.7 (5.7), respectively. Only illness coherence, emotional representations, pain and fatigue changed significantly between T0 and T2. Correlations between appreciation and changes in outcomes ranged between r=0.00 and r=0.34. Although a majority of subjects appreciated the written information, it did not have clinically relevant effects on illness perceptions, catastrophizing or impact of FM on daily life. Written education about pain neurophysiology is inadequate toward changing illness perceptions, catastrophizing or perceived health status of participants with FM; education should be incorporated into a broader multidisciplinary self-management program. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  19. Denomination, Religious Context, and Suicide : Neo-Durkheimian Multilevel Explanations Tested with Individual and Contextual Data

    NARCIS (Netherlands)

    Tubergen, Frank van; Grotenhuis, Manfred te; Ultee, Wout

    2005-01-01

    In Suicide, Durkheim found that involvement in religious communities is inversely related to suicide risk. In this article, two explanations for this relationship are examined. One is that religious networks provide support. The other is that religious communities prohibit suicide. To examine these

  20. Neurophysiological evidence of impaired self-monitoring in schizotypal personality disorder and its reversal by dopaminergic antagonism

    OpenAIRE

    Mireia Rabella; Eva Grasa; Iluminada Corripio; Sergio Romero; Miquel Àngel Mañanas; Rosa Mª. Antonijoan; Thomas F. Münte; Víctor Pérez; Jordi Riba

    2016-01-01

    BACKGROUND: Schizotypal personality disorder (SPD) is a schizophrenia-spectrum disorder characterized by odd or bizarre behavior, strange speech, magical thinking, unusual perceptual experiences, and social anhedonia. Schizophrenia proper has been associated with anomalies in dopaminergic neurotransmission and deficits in neurophysiological markers of self-monitoring, such as low amplitude in cognitive event-related brain potentials (ERPs) like the error-related negativity (ERN), and the erro...

  1. A flavor-safe composite explanation of $R_K$

    CERN Document Server

    Carmona, Adrian

    2017-05-04

    In these proceedings we discuss a flavor-safe explanation of the anomaly found in $R_K= {\\cal B}(B \\to K \\mu^+ \\mu^-)/{\\cal B}(B \\to K e^+ e^-)$ by LHCb, within the framework of composite Higgs models. We present a model featuring a non-negligible degree of compositeness for all three generations of right-handed leptons, which leads to a violation of lepton-flavor universality in neutral current interactions while other constraints from quark- and lepton-flavor physics are met. Moreoever, the particular embedding of the lepton sector considered in this setup provides a parametrically enhanded contribution to the Higgs mass that can weak considerably the need for ultra-light top partners.

  2. Competence Matching Tool - Explanations and Implementation

    NARCIS (Netherlands)

    Herder, Eelco; Kärger, Philipp

    2010-01-01

    Herder, E., Kärger, P. (2009) Competence Matching Tool - Explanations and Implementation. The document contains the technical specification of the competence matching tool. The tool can be found at http://tencompetence.cvs.sourceforge.net/viewvc/tencompetence/wp7/CompetenceMatcher/ and the location

  3. Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution.

    Science.gov (United States)

    Guillén, Yolanda; Ruiz, Alfredo

    2012-02-01

    Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution.

  4. Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution

    Directory of Open Access Journals (Sweden)

    Guillén Yolanda

    2012-02-01

    Full Text Available Abstract Background Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. Results In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. Conclusions D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution.

  5. Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution

    Science.gov (United States)

    2012-01-01

    Background Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. Results In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. Conclusions D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution. PMID:22296923

  6. Development in the neurophysiology of emotion processing and memory in school-age children

    Directory of Open Access Journals (Sweden)

    Jacqueline S. Leventon

    2014-10-01

    Full Text Available In the adult literature, emotional arousal is regarded as a source of the enhancing effect of emotion on subsequent memory. Here, we used behavioral, electrophysiological, and psychophysiological methods to examine the role of emotional arousal on subsequent memory in school-age children. Five- to 8-year-olds, divided into younger and older groups, viewed emotional scenes as EEG, heart rate, and respiration was recorded, and participated in a memory task 24 hours later where EEG and behavioral responses were recorded; participants provided subjective ratings of the scenes after the memory task. All measures indicated emotion responses in both groups, and in ERP measures the effects were stronger for older children. Emotion responses were more consistent across measures for negative than positive stimuli. Behavioral memory performance was strong but did not differ by emotion condition. Emotion influenced the ERP index of recognition memory in the older group only (enhanced recognition of negative scenes. The findings an increasing interaction of emotion and memory during the school years. Further, the findings impress the value of combining multiple methods to assess emotion and memory in development. Development in the neurophysiology of emotion processing and memory in school-age children.

  7. Separable explanations of neural network decisions

    DEFF Research Database (Denmark)

    Rieger, Laura

    2017-01-01

    Deep Taylor Decomposition is a method used to explain neural network decisions. When applying this method to non-dominant classifications, the resulting explanation does not reflect important features for the chosen classification. We propose that this is caused by the dense layers and propose...

  8. Exploring Dominant Types of Explanations Built by General Chemistry Students

    Science.gov (United States)

    Talanquer, Vicente

    2010-01-01

    The central goal of our study was to explore the nature of the explanations generated by science and engineering majors with basic training in chemistry to account for the colligative properties of solutions. The work was motivated by our broader interest in the characterisation of the dominant types of explanations that science college students…

  9. How perceptions of experience-based analysis influence explanations of work accidents.

    Science.gov (United States)

    Mbaye, Safiétou; Kouabenan, Dongo Rémi

    2013-12-01

    This article looks into how perceptions of experience-based analysis (EBA) influence causal explanations of accidents given by managers and workers in the chemical industry (n=409) and in the nuclear industry (n=222). The approach is based on the model of naive explanations of accidents (Kouabenan, 1999, 2006, 2009), which recommends taking into account explanations of accidents spontaneously given by individuals, including laypersons, not only to better understand why accidents occur but also to design and implement the most appropriate prevention measures. The study reported here describes the impact of perceptions about EBA (perceived effectiveness, personal commitment, and the feeling of being involved in EBA practices) on managers' and workers' explanations of accidents likely to occur at the workplace. The results indicated that both managers and workers made more internal explanations than external ones when they perceived EBA positively. Moreover, the more the participants felt involved in EBA, were committed to it, and judged it effective, the more they explained accidents in terms of factors internal to the workers. Recommendations are proposed for reducing defensive reactions, increasing personal commitment to EBA, and improving EBA effectiveness. © 2013.

  10. The geomagnetic field - An explanation for the microturbulence in coaxial gun plasmas

    Science.gov (United States)

    Mather, J. W.; Ahluwalia, H. S.

    1988-01-01

    The complexity introduced by the geomagnetic field in several regions of a coaxial gun plasma device is described. It is shown that the annihilation of the swept-up geomagnetic flux, trapped within the highly compressed turbulent plasma, provides an explanation for varied performance and experimental results. The results indicate that the device should be aligned along the direction of the local geomagnetic field or enclosed in a mu-metal shield.

  11. The clinical practice of intraoperative neurophysiological monitoring in Shanghai Huashan Hospital

    Directory of Open Access Journals (Sweden)

    WU Jin-song

    2012-12-01

    Full Text Available Intraoperative neurophysiological monitoring (IONM is the gold standard of the intraoperative functional brain mapping. It employs various electrophysiological methods such as awake craniotomy, intraoperative somatosensory and motor evoked potentials monitoring, intraoperative cortical stimulation and sub-cortical stimulation to accurately map the cortical and sub-cortical nervous pathways so that the continuous assessment and real -time protection of the functional integrity of certain neural structures can be achieved during surgery. Based on decades of clinical practice, the Department of Neurosurgery of Shanghai Huashan Hospital has set up an "IONM clinical practice guideline" used in the institute. The clinical practice guideline covers technical and operation standards of IONM in all kinds of common neurosurgery diseases and does improve the clinical efficacy in neurosurgical procedures.

  12. Strategic Explanations for a Diagnostic Consultation System. Technical Report #8.

    Science.gov (United States)

    Hasling, Diane Warner; And Others

    This paper examines the problem of automatic explanation of reasoning, or the ability of a program to discuss what it is doing in some understandable way, particularly as part of an expert system. An introduction presents a general framework in which to view explanation and reviews some of the research in this area. This is followed by a…

  13. The impact of 3D and 2D TV watching on neurophysiological responses and cognitive functioning in adults.

    Science.gov (United States)

    Jeong, Hyun-Ghang; Ko, Young-Hoon; Han, Changsu; Oh, So-Young; Park, Kun Woo; Kim, Taehee; Ko, Deokwon

    2015-12-01

    Watching three-dimensional television (3D TV) may strain the eyes. However, other potential harmful effects of 3D TV watching have been rarely investigated. The current study examined the impact of 3D TV watching on neurophysiological responses and cognitive functioning as compared with two-dimensional TV (2D TV) watching. A total of 72 individuals were randomly assigned to either a 3D TV watching group or a 2D TV watching group. Electroencephalography (EEG) was used to measure neurophysiological responses, and computerized neurocognitive tests were conducted immediately before and after TV watching. The Simulator Sickness Questionnaire (SSQ) was used to assess visual discomfort. There was a significant change in visual discomfort between the two groups (SSQ score at baseline: 2.28 ± 3.05 for the 3D TV group and 3.69 ± 3.49 for the 2D TV group; SSQ score after watching TV: 4.6 ± 3.35 for the 3D TV group and 4.03 ± 3.47 for the 2D TV group), and this change was greater for the 3D TV watching group (P = 0.025). However, 3D TV watching did not have a differential impact on EEG responses. Furthermore, there were no significant differences between the groups in terms of changes in cognitive performance, except for a subtle difference in backward digit span performance. Our findings suggest that 3D TV watching is as safe as 2D TV watching in terms of neurophysiological responses and cognitive functioning. Potential harmful effects of TV viewing might be similar regardless of whether 3D or 2D TV is viewed. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  14. Neurophysiological mechanisms of circadian cognitive control in RLS patients - an EEG source localization study

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2017-01-01

    Full Text Available The circadian variation of sensory and motor symptoms with increasing severity in the evening and at night is a key diagnostic feature/symptom of the restless legs syndrome (RLS. Even though many neurological diseases have shown a strong nexus between motor and cognitive symptoms, it has remained unclear whether cognitive performance of RLS patients declines in the evening and which neurophysiological mechanisms are affected by the circadian variation. In the current study, we examined daytime effects (morning vs. evening on cognitive performance in RLS patients (n = 33 compared to healthy controls (n = 29 by analyzing flanker interference effects in combination with EEG and source localization techniques. RLS patients showed larger flanker interference effects in the evening than in the morning (p = .023, while healthy controls did not display a comparable circadian variation. In line with this, the neurophysiological data showed smaller N1 amplitudes in RLS patients compared to controls in the interfering task condition in the evening (p = .042, but not in the morning. The results demonstrate diurnal cognitive changes in RLS patients with intensified impairments in the evening. It seems that not all dopamine-regulated cognitive processes are altered in RLS and thus show daytime-dependent impairments. Instead, the daytime-related cognitive impairment emerges from attentional selection processes within the extra-striate visual cortex, but not from later cognitive processes such as conflict monitoring and response selection.

  15. Intrinsic neurophysiological properties of hilar ectopic and normotopic dentate granule cells in human temporal lobe epilepsy and a rat model.

    Science.gov (United States)

    Althaus, A L; Sagher, O; Parent, J M; Murphy, G G

    2015-02-15

    Hilar ectopic dentate granule cells (DGCs) are a salient feature of aberrant plasticity in human temporal lobe epilepsy (TLE) and most rodent models of the disease. Recent evidence from rodent TLE models suggests that hilar ectopic DGCs contribute to hyperexcitability within the epileptic hippocampal network. Here we investigate the intrinsic excitability of DGCs from humans with TLE and the rat pilocarpine TLE model with the objective of comparing the neurophysiology of hilar ectopic DGCs to their normotopic counterparts in the granule cell layer (GCL). We recorded from 36 GCL and 7 hilar DGCs from human TLE tissue. Compared with GCL DGCs, hilar DGCs in patient tissue exhibited lower action potential (AP) firing rates, more depolarized AP threshold, and differed in single AP waveform, consistent with an overall decrease in excitability. To evaluate the intrinsic neurophysiology of hilar ectopic DGCs, we made recordings from retrovirus-birthdated, adult-born DGCs 2-4 mo after pilocarpine-induced status epilepticus or sham treatment in rats. Hilar DGCs from epileptic rats exhibited higher AP firing rates than normotopic DGCs from epileptic or control animals. They also displayed more depolarized resting membrane potential and wider AP waveforms, indicating an overall increase in excitability. The contrasting findings between disease and disease model may reflect differences between the late-stage disease tissue available from human surgical specimens and the earlier disease stage examined in the rat TLE model. These data represent the first neurophysiological characterization of ectopic DGCs from human hippocampus and prospectively birthdated ectopic DGCs in a rodent TLE model. Copyright © 2015 the American Physiological Society.

  16. Neurophysiological mechanisms in acceptance and commitment therapy in opioid-addicted patients with chronic pain.

    Science.gov (United States)

    Smallwood, Rachel F; Potter, Jennifer S; Robin, Donald A

    2016-04-30

    Acceptance and Commitment Therapy (ACT) has been effectively utilized to treat both chronic pain and substance use disorder independently. Given these results and the vital need to treat the comorbidity of the two disorders, a pilot ACT treatment was implemented in individuals with comorbid chronic pain and opioid addiction. This pilot study supported using neurophysiology to characterize treatment effects and revealed that, following ACT, participants with this comorbidity exhibited reductions in brain activation due to painful stimulus and in connectivity at rest. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. [Surgical treatment of eloquent brain area tumors using neurophysiological mapping of the speech and motor areas and conduction tracts].

    Science.gov (United States)

    Zuev, A A; Korotchenko, E N; Ivanova, D S; Pedyash, N V; Teplykh, B A

    To evaluate the efficacy of intraoperative neurophysiological mapping in removing eloquent brain area tumors (EBATs). Sixty five EBAT patients underwent surgical treatment using intraoperative neurophysiological mapping at the Pirogov National Medical and Surgical Center in the period from 2014 to 2015. On primary neurological examination, 46 (71%) patients were detected with motor deficits of varying severity. Speech disorders were diagnosed in 17 (26%) patients. Sixteen patients with concomitant or isolated lesions of the speech centers underwent awake surgery using the asleep-awake-asleep protocol. Standard neurophysiological monitoring included transcranial stimulation as well as motor and, if necessary, speech mapping. The motor and speech areas were mapped with allowance for the preoperative planning data (obtained with a navigation station) synchronized with functional MRI. In this case, a broader representation of the motor and speech centers was revealed in 12 (19%) patients. During speech mapping, no speech disorders were detected in 7 patients; in 9 patients, stimulation of the cerebral cortex in the intended surgical area induced motor (3 patients), sensory (4), and amnesic (2) aphasia. In the total group, we identified 11 patients in whom the tumor was located near the internal capsule. Upon mapping of the conduction tracts in the internal capsule area, the stimulus strength during tumor resection was gradually decreased from 10 mA to 5 mA. Tumor resection was stopped when responses retained at a stimulus strength of 5 mA, which, when compared to the navigation data, corresponded to a distance of about 5 mm to the internal capsule. Completeness of tumor resection was evaluated (contrast-enhanced MRI) in all patients on the first postoperative day. According to the control MRI data, the tumor was resected totally in 60% of patients, subtotally in 24% of patients, and partially in 16% of patients. In the early postoperative period, the development or

  18. Self-Explanation and Reading Strategy Training (SERT) Improves Low-Knowledge Students' Science Course Performance

    Science.gov (United States)

    McNamara, Danielle S.

    2017-01-01

    This study demonstrates the generalization of previous laboratory results showing the benefits of Self-Explanation Reading Training (SERT) to college students' course exam performance. The participants were 265 students enrolled in an Introductory Biology course, 59 of whom were provided with SERT. The results showed that SERT benefited students…

  19. Refining Students' Explanations of an Unfamiliar Physical Phenomenon-Microscopic Friction

    Science.gov (United States)

    Corpuz, Edgar De Guzman; Rebello, N. Sanjay

    2017-08-01

    The first phase of this multiphase study involves modeling of college students' thinking of friction at the microscopic level. Diagnostic interviews were conducted with 11 students with different levels of physics backgrounds. A phenomenographic approach of data analysis was used to generate categories of responses which subsequently were used to generate a model of explanation. Most of the students interviewed consistently used mechanical interactions in explaining microscopic friction. According to these students, friction is due to the interlocking or rubbing of atoms. Our data suggest that students' explanations of microscopic friction are predominantly influenced by their macroscopic experiences. In the second phase of the research, teaching experiment was conducted with 18 college students to investigate how students' explanations of microscopic friction can be refined by a series of model-building activities. Data were analyzed using Redish's two-level transfer framework. Our results show that through sequences of hands-on and minds-on activities, including cognitive dissonance and resolution, it is possible to facilitate the refinement of students' explanations of microscopic friction. The activities seemed to be productive in helping students activate associations that refine their ideas about microscopic friction.

  20. Selective effects of explanation on learning during early childhood.

    Science.gov (United States)

    Legare, Cristine H; Lombrozo, Tania

    2014-10-01

    Two studies examined the specificity of effects of explanation on learning by prompting 3- to 6-year-old children to explain a mechanical toy and comparing what they learned about the toy's causal and non-causal properties with children who only observed the toy, both with and without accompanying verbalization. In Study 1, children were experimentally assigned to either explain or observe the mechanical toy. In Study 2, children were classified according to whether the content of their response to an undirected prompt involved explanation. Dependent measures included whether children understood the toy's functional-mechanical relationships, remembered perceptual features of the toy, effectively reconstructed the toy, and (for Study 2) generalized the function of the toy when constructing a new one. Results demonstrate that across age groups, explanation promotes causal learning and generalization but does not improve (and in younger children can even impair) memory for causally irrelevant perceptual details. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  1. The Coexistence of Natural and Supernatural Explanations across Cultures and Development

    Science.gov (United States)

    Legare, Cristine H.; Evans, E. Margaret; Rosengren, Karl S.; Harris, Paul L.

    2012-01-01

    Although often conceptualized in contradictory terms, the common assumption that natural and supernatural explanations are incompatible is psychologically inaccurate. Instead, there is considerable evidence that the same individuals use both natural and supernatural explanations to interpret the very same events and that there are multiple ways in…

  2. Neurophysiological changes in the central and peripheral nervous system of streptozotocin-diabetic rats. Course of development and effects of insulin treatment

    NARCIS (Netherlands)

    Gispen, W.H.; Biessels, G.J.; Cristino, N.A.; Rutten, G.J.; Hamers, F.P.; Erkelens, D.W.

    1999-01-01

    Diabetes mellitus can affect both the peripheral and the central nervous system. However, central deficits are documented less well than peripheral deficits. We therefore compared the course of development of neurophysiological changes in the central and peripheral nervous systems in

  3. Memory accessibility shapes explanation: Testing key claims of the inherence heuristic account.

    Science.gov (United States)

    Hussak, Larisa J; Cimpian, Andrei

    2018-01-01

    People understand the world by constructing explanations for what they observe. It is thus important to identify the cognitive processes underlying these judgments. According to a recent proposal, everyday explanations are often constructed heuristically: Because people need to generate explanations on a moment-by-moment basis, they cannot perform an exhaustive search through the space of possible reasons, but may instead use the information that is most easily accessible in memory (Cimpian & Salomon 2014a, b). In the present research, we tested two key claims of this proposal that have so far not been investigated. First, we tested whether-as previously hypothesized-the information about an entity that is most accessible in memory tends to consist of inherent or intrinsic facts about that entity, rather than extrinsic (contextual, historical, etc.) facts about it (Studies 1 and 2). Second, we tested the implications of this difference in the memory accessibility of inherent versus extrinsic facts for the process of generating explanations: Does the fact that inherent facts are more accessible than relevant extrinsic facts give rise to an inherence bias in the content of the explanations generated (Studies 3 and 4)? The findings supported the proposal that everyday explanations are generated in part via a heuristic process that relies on easily accessible-and often inherent-information from memory.

  4. Excessive bodybuilding as pathology? A first neurophysiological classification.

    Science.gov (United States)

    Maier, Moritz Julian; Haeussinger, Florian Benedikt; Hautzinger, Martin; Fallgatter, Andreas Jochen; Ehlis, Ann-Christine

    2017-11-15

    Excessive bodybuilding as a pathological syndrome has been classified based on two different theories: bodybuilding as dependency or as muscle dysmorphic disorder (MDD). This study is a first attempt to find psychophysiological data supporting one of these classifications. Twenty-four participants (bodybuilders vs healthy controls) were presented with pictures of bodies, exercise equipment or general reward stimuli in a control or experimental condition, and were measured with functional near-infrared spectroscopy (fNIRS). Higher activation in the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) while watching bodies and training equipment in the experimental condition (muscular bodies and bodybuilding-typical equipment) would be an indicator for the addiction theory. Higher activation in motion-related areas would be an indicator for the MDD theory. We found no task-related differences between the groups in the DLPFC and OFC, but a significantly higher activation in bodybuilders in the primary somatosensory cortex (PSC) and left-hemispheric supplementary motor area (SMA) while watching body pictures (across conditions) as compared to the control group. These neurophysiological results could be interpreted as a first evidence for the MDD theory of excessive bodybuilding.

  5. Social Facilitation Effects by Pedagogical Conversational Agent: Lexical Network Analysis in an Online Explanation Task

    Science.gov (United States)

    Hayashi, Yugo

    2015-01-01

    The present study investigates web-based learning activities of undergraduate students who generate explanations about a key concept taught in a large-scale classroom. The present study used an online system with Pedagogical Conversational Agent (PCA), asked to explain about the key concept from different points and provided suggestions and…

  6. Evolutionary explanations in medicine: how do they differ and how to benefit from them.

    Science.gov (United States)

    Lozano, George A

    2010-04-01

    Evolutionary explanations, many of which have appeared on the pages of this journal, are becoming more pervasive and influential in medicine, so it is becoming more important to understand how these types of explanations differ from the proximate approach that is more common in medicine, and how the evolutionary approach can contribute to medicine. Understanding of any biological phenomenon can occur at four levels: (1) ontogeny (2) causation, (3) function and (4) evolution. These approaches are not mutually exclusive, and whereas the first two are more common in medical practice, a complete explanation requires all four levels of analysis. Two major differences among these approaches are the apparent degree of immediacy associated with them, and the extent to which they apply to individuals rather than populations. Criticisms of adaptive explanations often arise from a failure to understand the complementary nature of these four types of explanations. Other unwarranted criticisms result from a failure to appreciate that adaptive explanations often apply to populations, not individuals. A third type of criticism is driven by the mistaken belief that adaptive explanations somehow justify morally reprehensible behaviours. Finally, evolutionary explanations sometimes face the criticism of "personal incredulity". Adaptive explanations must be consistent with basic evolutionary concepts and must adhere to the physical reality of the phenomenon in question. Their value, however, comes not in devising a seemingly rational explanation, but in their predictions. Testable predictions must be explicitly stated and clearly articulated. They must differ from those of arising from other hypotheses and must not only be interesting to evolutionary biologists, but also useful to medical practitioners. Integration of the proximate and the ultimate approaches is possible and potentially beneficial to both evolutionists and physicians, but it requires some basic understanding of our

  7. Predicting Mental Imagery-Based BCI Performance from Personality, Cognitive Profile and Neurophysiological Patterns.

    Directory of Open Access Journals (Sweden)

    Camille Jeunet

    Full Text Available Mental-Imagery based Brain-Computer Interfaces (MI-BCIs allow their users to send commands to a computer using their brain-activity alone (typically measured by ElectroEncephaloGraphy-EEG, which is processed while they perform specific mental tasks. While very promising, MI-BCIs remain barely used outside laboratories because of the difficulty encountered by users to control them. Indeed, although some users obtain good control performances after training, a substantial proportion remains unable to reliably control an MI-BCI. This huge variability in user-performance led the community to look for predictors of MI-BCI control ability. However, these predictors were only explored for motor-imagery based BCIs, and mostly for a single training session per subject. In this study, 18 participants were instructed to learn to control an EEG-based MI-BCI by performing 3 MI-tasks, 2 of which were non-motor tasks, across 6 training sessions, on 6 different days. Relationships between the participants' BCI control performances and their personality, cognitive profile and neurophysiological markers were explored. While no relevant relationships with neurophysiological markers were found, strong correlations between MI-BCI performances and mental-rotation scores (reflecting spatial abilities were revealed. Also, a predictive model of MI-BCI performance based on psychometric questionnaire scores was proposed. A leave-one-subject-out cross validation process revealed the stability and reliability of this model: it enabled to predict participants' performance with a mean error of less than 3 points. This study determined how users' profiles impact their MI-BCI control ability and thus clears the way for designing novel MI-BCI training protocols, adapted to the profile of each user.

  8. The Many Roles of "Explanation" in Science Education: A Case Study

    Science.gov (United States)

    Rocksén, Miranda

    2016-01-01

    In this paper the role of explanations is discussed in relation to possible consequences originating in the polysemy of the word explanation. The present study is a response to conceptual confusions that have arisen in the intersection between theory and practice, and between science education literature and communication in authentic science…

  9. Neuropsychological and neurophysiological approaches to study of variants of Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Matveyeva E. Yu.

    2012-06-01

    Full Text Available The present review carries out analysis of empirical studies concerning neuropsychological and neurophysiological mechanisms of Attention Deficit Hyperactivity Disorder (ADHD. The current data, regarding malfunctions of brain systems at various levels of aetiopathogenesis (genetic, neurotrasmitting, functioning of separate brain structure, are discussed. The article regards the character of deficit in various components of psychic activity in people with ADHD, namely, executive functions and temporary storage (working memory, activating and neurodynamic components of activity, separate operational characteristics, and motivational impairments of patients with ADHD. The possibility of disclosing some clinical variants of the ADHD syndrome, differing in mechanisms, is also discussed in the article.

  10. Assessing the place of neurobiological explanations in accounts of a family member's addiction.

    Science.gov (United States)

    Meurk, Carla; Fraser, Doug; Weier, Megan; Lucke, Jayne; Carter, Adrian; Hall, Wayne

    2016-07-01

    The brain disease model of addiction posits that addiction is a persistent form of neural dysfunction produced by chronic drug use, which makes it difficult for addicted persons to become and remain abstinent. As part of an anticipatory policy analysis of addiction neuroscience, we engaged family members of addicted individuals to assess their views on the place and utility of brain-based accounts of addiction. Fifteen in-depth qualitative interviews were conducted and used to develop a quantitative online survey that was completed by 55 family members. This article reports responses on what addiction is and how it is caused and responses to explanations of the brain disease model of addiction. Participants gave multiple reasons for their family members developing an addiction and there was no single dominant belief about the best way to describe addiction. Participants emphasised the importance of both scientific and non-scientific perspectives on addiction by providing multifactorial explanations of their family members' addictions. Most family members acknowledged that repeated drug use can cause changes to the brain, but they varied in their reactions to labelling addiction a 'brain disease'. They believed that understanding addiction, and how it is caused, could help them support their addicted relative. Participants' beliefs about neurobiological information and the brain disease model of addiction appeared to be driven by empathetic, utilitarian considerations rather than rationalist ones. We discuss the importance of providing information about the nature and causes of addiction. [Meurk C, Fraser D, Weier M, Lucke J, Carter A, Hall W. Assessing the place of neurobiological explanations in accounts of a family member's addiction. Drug Alcohol Rev 2016;35:461-469]. © 2015 Australasian Professional Society on Alcohol and other Drugs.

  11. Multiple frequency audio signal communication as a mechanism for neurophysiology and video data synchronization.

    Science.gov (United States)

    Topper, Nicholas C; Burke, Sara N; Maurer, Andrew Porter

    2014-12-30

    Current methods for aligning neurophysiology and video data are either prepackaged, requiring the additional purchase of a software suite, or use a blinking LED with a stationary pulse-width and frequency. These methods lack significant user interface for adaptation, are expensive, or risk a misalignment of the two data streams. A cost-effective means to obtain high-precision alignment of behavioral and neurophysiological data is obtained by generating an audio-pulse embedded with two domains of information, a low-frequency binary-counting signal and a high, randomly changing frequency. This enabled the derivation of temporal information while maintaining enough entropy in the system for algorithmic alignment. The sample to frame index constructed using the audio input correlation method described in this paper enables video and data acquisition to be aligned at a sub-frame level of precision. Traditionally, a synchrony pulse is recorded on-screen via a flashing diode. The higher sampling rate of the audio input of the camcorder enables the timing of an event to be detected with greater precision. While on-line analysis and synchronization using specialized equipment may be the ideal situation in some cases, the method presented in the current paper presents a viable, low cost alternative, and gives the flexibility to interface with custom off-line analysis tools. Moreover, the ease of constructing and implements this set-up presented in the current paper makes it applicable to a wide variety of applications that require video recording. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Clinical neurophysiology of fatigue.

    Science.gov (United States)

    Zwarts, M J; Bleijenberg, G; van Engelen, B G M

    2008-01-01

    reliability of the psychological and clinical neurophysiological assessment techniques available today allows a multidisciplinary approach to fatigue in neurological patients, which may contribute to the elucidation of the pathophysiological mechanisms of chronic fatigue, with the ultimate goal to develop tailored treatments for fatigue in neurological patients. The present report discusses the different manifestations of fatigue and the available tools to assess peripheral and central fatigue.

  13. Development in the neurophysiology of emotion processing and memory in school-age children.

    Science.gov (United States)

    Leventon, Jacqueline S; Stevens, Jennifer S; Bauer, Patricia J

    2014-10-01

    In the adult literature, emotional arousal is regarded as a source of the enhancing effect of emotion on subsequent memory. Here, we used behavioral, electrophysiological, and psychophysiological methods to examine the role of emotional arousal on subsequent memory in school-age children. Five- to 8-year-olds, divided into younger and older groups, viewed emotional scenes as EEG, heart rate, and respiration was recorded, and participated in a memory task 24 hours later where EEG and behavioral responses were recorded; participants provided subjective ratings of the scenes after the memory task. All measures indicated emotion responses in both groups, and in ERP measures the effects were stronger for older children. Emotion responses were more consistent across measures for negative than positive stimuli. Behavioral memory performance was strong but did not differ by emotion condition. Emotion influenced the ERP index of recognition memory in the older group only (enhanced recognition of negative scenes). The findings an increasing interaction of emotion and memory during the school years. Further, the findings impress the value of combining multiple methods to assess emotion and memory in development. Development in the neurophysiology of emotion processing and memory in school-age children. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. The matchmaking paradox: a statistical explanation

    International Nuclear Information System (INIS)

    Eliazar, Iddo I; Sokolov, Igor M

    2010-01-01

    Medical surveys regarding the number of heterosexual partners per person yield different female and male averages-a result which, from a physical standpoint, is impossible. In this paper we term this puzzle the 'matchmaking paradox', and establish a statistical model explaining it. We consider a bipartite graph with N male and N female nodes (N >> 1), and B bonds connecting them (B >> 1). Each node is associated a random 'attractiveness level', and the bonds connect to the nodes randomly-with probabilities which are proportionate to the nodes' attractiveness levels. The population's average bonds-per-nodes B/N is estimated via a sample average calculated from a survey of size n (n >> 1). A comprehensive statistical analysis of this model is carried out, asserting that (i) the sample average well estimates the population average if and only if the attractiveness levels possess a finite mean; (ii) if the attractiveness levels are governed by a 'fat-tailed' probability law then the sample average displays wild fluctuations and strong skew-thus providing a statistical explanation to the matchmaking paradox.

  15. Towards to An Explanation for Conceptual Change: A Mechanistic Alternative

    Science.gov (United States)

    Rusanen, Anna-Mari

    2014-07-01

    Conceptual change is one of the most studied fields in science education and psychology of learning. However, there are still some foundational issues in conceptual change research on which no clear consensus has emerged. Firstly, there is no agreement on what changes in belief and concept systems constitute conceptual change and what changes do not. Secondly, there is no consensus on what the specific mechanisms of conceptual change are. Thirdly, there is no common explanatory framework of how to explain conceptual change. In this paper a sketch for explanations of conceptual change is outlined. According to this account, the explanation for conceptual change requires (1) a description for the information processing task and (2) a sufficiently accurate and detailed description of the cognitive mechanisms responsible for the task. The scope and limits of this type of explanation are discussed.

  16. Modeling systems-level dynamics: Understanding without mechanistic explanation in integrative systems biology.

    Science.gov (United States)

    MacLeod, Miles; Nersessian, Nancy J

    2015-02-01

    In this paper we draw upon rich ethnographic data of two systems biology labs to explore the roles of explanation and understanding in large-scale systems modeling. We illustrate practices that depart from the goal of dynamic mechanistic explanation for the sake of more limited modeling goals. These processes use abstract mathematical formulations of bio-molecular interactions and data fitting techniques which we call top-down abstraction to trade away accurate mechanistic accounts of large-scale systems for specific information about aspects of those systems. We characterize these practices as pragmatic responses to the constraints many modelers of large-scale systems face, which in turn generate more limited pragmatic non-mechanistic forms of understanding of systems. These forms aim at knowledge of how to predict system responses in order to manipulate and control some aspects of them. We propose that this analysis of understanding provides a way to interpret what many systems biologists are aiming for in practice when they talk about the objective of a "systems-level understanding." Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Using Self-Explanations in the Laboratory to Connect Theory and Practice: The Decision/ Explanation/Observation/Inference Writing Method

    Science.gov (United States)

    Van Duzor, Andrea Gay

    2016-01-01

    While many faculty seek to use student-centered, inquiry-based approaches in teaching laboratories, transitioning from traditional to inquiry instruction can be logistically challenging. This paper outlines use of a laboratory notebook and report writing-to-learn method that emphasizes student self-explanations of procedures and outcomes,…

  18. Examining Alternative Explanations of the Covariation of ADHD and Anxiety Symptoms in Children: A Community Study

    Science.gov (United States)

    Baldwin, Jennifer S.; Dadds, Mark R.

    2008-01-01

    Attention-deficit hyperactivity disorder (ADHD) is comorbid with a range of other disorders, including anxiety disorders. The aim was to examine different explanations for the covariation of these symptom domains in children according to the framework provided by (Lilienfeld, S. O. Comorbidity between and within childhood externalizing and…

  19. Dynamical explanation for the high water abundance detected in Orion

    International Nuclear Information System (INIS)

    Elitzur, M.

    1979-01-01

    Shock wave chemistry is suggested as the likely explanation for the high water abundance which has been recently detected in Orion by Phyllips et al. The existence of such a shock and its inferred properties are in agreement with other observations of Orion such as the broad velocity feature and H 2 vibration emission. Shock waves are proposed as the likely explanation for high water abundances observed in other sources such as the strong H 2 O masers

  20. [Neurophysiological methods in evaliuation of neurorehabiltation in children].

    Science.gov (United States)

    Świerczyńska, Anna; Kłusek, Renata; Kaciński, Marek

    2016-01-01

    The authors reviewed neurophysiological methods, which are used in the evaluation of children referred for neurorehabilitation. Rehabilitation techniques which may stimulate or provoke pathological changes in EEG must be ruled out. Electrophysiological and clinical improvement allow for the extension and intensification of rehabilitation. Normal EEG pattern ensures the safe use of techniques consisting of neuromuscular re-education or passive verticalisation, electrotherapy and thermotherapy. Quantitative and qualitative assessment of cognitive impairment is based on neuropsychological tests and endogenous evoked potentials (most often P300). Presence of cognitive dysfunction needs the use of neuropsychological and neurologopedic therapy. Based on results of exogenous evoked potentials appropriate neurorehabilitation program (physiotherapy, kinezytherapy) can be determined and clinical outcome predicted. EMG allows appropriate usage of applications, patterns and principles in the PNF method (such as compression, stretching, resistance), adapting them optimally to the possibility of a child. ENG estimates conduction in motor and sensory nerves. Based on the results nerve impairment can be localized, severity and character of damage estimated (demyelinating, axonal or complex) and course of the disease and treatment monitored. Short characteristics of 37 children with Guillain-Barre syndrome referred for rehabilitation was presented. Special attention was drawn to floppy infants. Results of neuroelectrophysiological examinations determine suitable rehabilitation program adjusted to the course of central nervous system impairment.

  1. Artificial gravity exposure impairs exercise-related neurophysiological benefits.

    Science.gov (United States)

    Vogt, Tobias; Abeln, Vera; Strüder, Heiko K; Schneider, Stefan

    2014-01-17

    Artificial gravity (AG) exposure is suggested to counteract health deconditioning, theoretically complementing exercise during space habitations. Exercise-benefits on mental health are well documented (i.e. well-being, enhanced executive functions). Although AG is coherent for the integrity of fundamental physiological systems, the effects of its exposure on neurophysiological processes related to cognitive performance are poorly understood and therefore characterize the primary aim of this study. 16 healthy males participated in two randomly assigned sessions, AG and exercise (30minute each). Participants were exposed to AG at continuous +2Gz in a short-arm human centrifuge and performed moderate exercise (cycling ergometer). Using 64 active electrodes, resting EEG was recorded before (pre), immediately after (post), and 15min after (post15) each session. Alpha (7.5-12.5Hz) and beta frequencies (12.5-35.0Hz) were exported for analysis. Cognitive performance and mood states were assessed before and after each session. Cognitive performance improved after exercise (pexercise, however not after AG. Frontal alpha (post pexercise. Relaxed cortical states were indicated after exercise, but were less apparent after AG. Changes in mood states failed significance after both sessions. Summarized, the benefits to mental health, recorded after exercise, were absent after AG, indicating that AG might cause neurocognitive deconditioning. © 2013.

  2. Transforming Biology Assessment with Machine Learning: Automated Scoring of Written Evolutionary Explanations

    Science.gov (United States)

    Nehm, Ross H.; Ha, Minsu; Mayfield, Elijah

    2012-01-01

    This study explored the use of machine learning to automatically evaluate the accuracy of students' written explanations of evolutionary change. Performance of the Summarization Integrated Development Environment (SIDE) program was compared to human expert scoring using a corpus of 2,260 evolutionary explanations written by 565 undergraduate…

  3. Age and the Explanation of Crime, Revisited

    Science.gov (United States)

    Sweeten, Gary; Piquero, Alex R.; Steinberg, Laurence

    2013-01-01

    Age is one of the most robust correlates of criminal behavior. Yet, explanations for this relationship are varied and conflicting. Developmental theories point to a multitude of sociological, psychological, and biological changes that occur during adolescence and adulthood. One prominent criminological perspective outlined by Gottfredson and…

  4. Theism and Inference to the Best Explanation

    NARCIS (Netherlands)

    Holten, W. van

    2002-01-01

    In this paper the author critically examines the explanatory role of theistic belief. Although talk of religious beliefs as explanations is commonly employed in the context of religious epistemology, it may also serve to simply characterise one of the functions of religious views of life. It is

  5. Theism and inference to the Best Explanation

    NARCIS (Netherlands)

    Holten, Wilko van

    2002-01-01

    In this paper the author critically examines the explanatory role of theistic belief. Although talk of religious beliefs as explanations is commonly employed in the context of religious epistemology, it may also serve to simply characterise one of the functions of religious views of life. It is

  6. Cultural border crossing: The interaction between fundamental Christian beliefs and scientific explanations

    Science.gov (United States)

    Elimbi, Celestine Nakeli

    The purpose of this study is to investigate the interaction between people's fundamental Christian beliefs and scientific explanations. When people with fundamental Christian beliefs encounter scientific explanations, such explanations may interact with their deeply rooted beliefs in a way that is likely to produce tensions. It is expedient to understand the classroom/professional experiences of such individuals and how they manage these tensions. I will apply Jegede's collateral learning theory as a lens to look at how individuals manage the tensions between their religious and scientific worldviews. Gaining insight into people's experiences in the classroom/work place and how they manage these tensions will potentially inform classroom instruction and ways by which we can help students with fundamental Christian beliefs maintain their pursuit of science related careers by easing the nature of the borders they cross. Sources of data will include participant reported perspectives of how they manage the tensions and observations of real-time resolution of potentially conflicting explanations from their religious and scientific worldviews.

  7. The coexistence of natural and supernatural explanations within and across domains and development.

    Science.gov (United States)

    Busch, Justin T A; Watson-Jones, Rachel E; Legare, Cristine H

    2017-03-01

    People across highly diverse cultural contexts use both natural and supernatural explanations to explain questions of fundamental concern such as death, illness, and human origins. The present study examines the development of explanatory coexistence within and across domains of existential concern in individuals in Tanna, Vanuatu. We examined three age groups: 7- to 12-year-old children, 13- to 18-year-old adolescents, and 19- to 70-year-old adults (N = 72). Within the domain of death, biological and spontaneous explanations were most common across all ages. For illness, children showed the highest rates of explanatory coexistence, while adolescents and adults favoured biological explanations. Within the human origins domain, theistic explanations were most common across the age groups. Overall, these data show that coexistence reasoning in these domains is pervasive across cultures, yet at the same time it is deeply contextually specific, reflecting the nuanced differences in local ecologies and cultural beliefs. Statement of contribution What is already known on this subject? Individuals across highly diverse cultural contexts use both natural and supernatural explanations to understand the events that occur in their lives. Context and cultural input play a large role in determining when and how individuals incorporate natural and supernatural explanations. The development of explanatory coexistence has primarily studied explanations for isolated domains. What does this study add? We examined explanatory coexistence in a culture with recent conversion to Christianity and formal education. The current research examines how individuals reason within and across the domains of human origins, illness, and death. Developmental differences associated with explanatory coexistence are examined. © 2016 The British Psychological Society.

  8. Provider expectations and father involvement: learning from ...

    African Journals Online (AJOL)

    2013-12-17

    Dec 17, 2013 ... in Gauteng's poor and black communities with fathers that did not ... affect fathers' ability to live up to provider expectations. ... On the contrary, father absence can exacerbate household poverty and “can ... socio-emotional development of the children, although such effects are not uniformly .... explanation.

  9. Students' explanations in complex learning of disciplinary programming

    Science.gov (United States)

    Vieira, Camilo

    Computational Science and Engineering (CSE) has been denominated as the third pillar of science and as a set of important skills to solve the problems of a global society. Along with the theoretical and the experimental approaches, computation offers a third alternative to solve complex problems that require processing large amounts of data, or representing complex phenomena that are not easy to experiment with. Despite the relevance of CSE, current professionals and scientists are not well prepared to take advantage of this set of tools and methods. Computation is usually taught in an isolated way from engineering disciplines, and therefore, engineers do not know how to exploit CSE affordances. This dissertation intends to introduce computational tools and methods contextualized within the Materials Science and Engineering curriculum. Considering that learning how to program is a complex task, the dissertation explores effective pedagogical practices that can support student disciplinary and computational learning. Two case studies will be evaluated to identify the characteristics of effective worked examples in the context of CSE. Specifically, this dissertation explores students explanations of these worked examples in two engineering courses with different levels of transparency: a programming course in materials science and engineering glass box and a thermodynamics course involving computational representations black box. Results from this study suggest that students benefit in different ways from writing in-code comments. These benefits include but are not limited to: connecting xv individual lines of code to the overall problem, getting familiar with the syntax, learning effective algorithm design strategies, and connecting computation with their discipline. Students in the glass box context generate higher quality explanations than students in the black box context. These explanations are related to students prior experiences. Specifically, students with

  10. Ontological Order in Scientific Explanation | Park | Philosophical ...

    African Journals Online (AJOL)

    A conceptually sound explanation, I claim, respects the ontological order between properties. A dependent property is to be explained in terms of its underlying property, not the other way around. The applicability of this point goes well beyond the realm of the debate between scientific realists and antirealists.

  11. Neurophysiology and Neuroanatomy of Reflexive and Volitional Saccades as Revealed by Lesion Studies with Neurological Patients and Transcranial Magnetic Stimulation (TMS)

    Science.gov (United States)

    Muri, Rene M.; Nyffeler, Thomas

    2008-01-01

    This review discusses the neurophysiology and neuroanatomy of the cortical control of reflexive and volitional saccades in humans. The main focus is on classical lesion studies and studies using the interference method of transcranial magnetic stimulation (TMS). To understand the behavioural function of a region, it is essential to assess…

  12. Social Groups, Explanation and Ontological Holism | Sheehy ...

    African Journals Online (AJOL)

    The paper begins from the claim that ontological holism is given prima facie plausibility by the apparently ineliminable role of groups in some descriptions and explanations of the social domain. If the individualist accepts the link between indispensabilty and realism, then individualism must show that groups cannot play the ...

  13. Foreword: Surface Tensions: Between Explanation and Understanding.

    Science.gov (United States)

    Blauvelt, Andrew

    1995-01-01

    Introduces this issue of the journal, which is devoted to new perspectives on critical histories of graphic design. Notes that the essays in this issue offer examples of the variety of interpretative approaches available that serve to question both the previously unchallenged acceptance of historical explanations and the transcendent understanding…

  14. Investigating Assessment Bias for Constructed Response Explanation Tasks: Implications for Evaluating Performance Expectations for Scientific Practice

    Science.gov (United States)

    Federer, Meghan Rector

    Assessment is a key element in the process of science education teaching and research. Understanding sources of performance bias in science assessment is a major challenge for science education reforms. Prior research has documented several limitations of instrument types on the measurement of students' scientific knowledge (Liu et al., 2011; Messick, 1995; Popham, 2010). Furthermore, a large body of work has been devoted to reducing assessment biases that distort inferences about students' science understanding, particularly in multiple-choice [MC] instruments. Despite the above documented biases, much has yet to be determined for constructed response [CR] assessments in biology and their use for evaluating students' conceptual understanding of scientific practices (such as explanation). Understanding differences in science achievement provides important insights into whether science curricula and/or assessments are valid representations of student abilities. Using the integrative framework put forth by the National Research Council (2012), this dissertation aimed to explore whether assessment biases occur for assessment practices intended to measure students' conceptual understanding and proficiency in scientific practices. Using a large corpus of undergraduate biology students' explanations, three studies were conducted to examine whether known biases of MC instruments were also apparent in a CR instrument designed to assess students' explanatory practice and understanding of evolutionary change (ACORNS: Assessment of COntextual Reasoning about Natural Selection). The first study investigated the challenge of interpreting and scoring lexically ambiguous language in CR answers. The incorporation of 'multivalent' terms into scientific discourse practices often results in statements or explanations that are difficult to interpret and can produce faulty inferences about student knowledge. The results of this study indicate that many undergraduate biology majors

  15. Impact of Self-Explanation and Analogical Comparison Support on Learning Processes, Motivation, Metacognition, and Transfer

    Science.gov (United States)

    Richey, J. Elizabeth

    Research examining analogical comparison and self-explanation has produced a robust set of findings about learning and transfer supported by each instructional technique. However, it is unclear how the types of knowledge generated through each technique differ, which has important implications for cognitive theory as well as instructional practice. I conducted a pair of experiments to directly compare the effects of instructional prompts supporting self-explanation, analogical comparison, and the study of instructional explanations across a number of fine-grained learning process, motivation, metacognition, and transfer measures. Experiment 1 explored these questions using sequence extrapolation problems, and results showed no differences between self-explanation and analogical comparison support conditions on any measure. Experiment 2 explored the same questions in a science domain. I evaluated condition effects on transfer outcomes; self-reported self-explanation, analogical comparison, and metacognitive processes; and achievement goals. I also examined relations between transfer and self-reported processes and goals. Receiving materials with analogical comparison support and reporting greater levels of analogical comparison were both associated with worse transfer performance, while reporting greater levels of self-explanation was associated with better performance. Learners' self-reports of self-explanation and analogical comparison were not related to condition assignment, suggesting that the questionnaires did not measure the same processes promoted by the intervention, or that individual differences in processing are robust even when learners are instructed to engage in self-explanation or analogical comparison.

  16. Free will: reconciling German civil law with Libet's neurophysiological studies on the readiness potential.

    Science.gov (United States)

    Kawohl, Wolfram; Habermeyer, Elmar

    2007-01-01

    The free will debate widely exceeds the neuroscientific and philosophical fields due to profound implications for legislation, case law and psychiatric expert opinion. Data from Benjamin Libet's experiments on the readiness potential have been used as an argument against personal responsibility and for changes in the law. Due to the explicit use of the term "free will" in German civil law, the psychiatrist as an expert witness is confronted with this debate. In this article we outline the role of this crucial term in German civil law and we describe the neurophysiologic challenge in the form of Libet's experiments, which is led on three levels: the correctness of the data, the impact on the question of whether free will exists and possible consequences for the law. We conclude that the problem of free will cannot be debated on the basis of the data provided by Libet's experiments and that doubts about the existence of a free will must not lead to changes in the law or in psychiatric expert testimony. Therefore, advice for the psychiatrist as an expert witness is offered on the basis of a psychopathological approach that takes into account cognitive and motivational preconditions and the structure of values and personality. Copyright (c) 2007 John Wiley & Sons, Ltd.

  17. Successful child psychotherapy of attention deficit/hyperactive disorder: an agitated depression explanation.

    Science.gov (United States)

    Seitler, Burton Norman

    2008-09-01

    Science tries to explain phenomena in ways that are demonstrable and replicable to develop logical, coherent, parsimonious, and predictive theoretical systems. Yet hyperactive children are given stimulants to "calm" them down, despite the fact that science would predict stimulants would increase hyperactivity. Bradley (1937, 1950) observed that half of the behavior-problem children to whom he administered a stimulant for one week became subdued. He called this finding paradoxical, speculating that inhibitory centers of the central nervous system were stimulated. While Bradley's assertion of a paradoxical reverse effect in children may be an empirical observation, it is not an explanation. The Attention Deficit/Hyperactive Disorder (ADHD) is inferred to exist from hyperactive behavior, which in turn, is inferred to be neurological in origin, a circular argument. An inevitable consequence of the belief in the hypothetical neurological etiology of ADHD is that children are typically given stimulants. Using the case of a seven-year old child, described as experiencing ADHD, who was treated successfully without medication as an illustration, the author provides an alternative, more parsimonious explanation of the etiology, suggesting that ADHD is related to agitated depression.

  18. Effect of pain neurophysiology education on physiotherapy students' understanding of chronic pain, clinical recommendations and attitudes towards people with chronic pain: a randomised controlled trial.

    Science.gov (United States)

    Colleary, G; O'Sullivan, K; Griffin, D; Ryan, C G; Martin, D J

    2017-12-01

    To investigate the effect of pain neurophysiology education (PNE) on student physiotherapists': (1) knowledge of chronic pain; (2) attitudes towards patients with chronic pain; and (3) clinical recommendations for patients with chronic pain. Multicentre single-blind randomised controlled trial. One UK and one Irish university. Seventy-two student physiotherapists. Participants received either PNE (intervention) or a control education. Both were delivered in a 70-minute group lecture. (1) The Revised Pain Neurophysiology Quiz to assess knowledge; (2) the Health Care Pain Attitudes and Impairment Relationship Scale (HC-PAIRS) to assess attitudes; and (3) a case vignette to assess the appropriateness of clinical recommendations. Post education, the PNE group had a greater increase in pain neurophysiology knowledge [mean difference 4.0 (95% confidence interval 3.2 to 4.7), Pstudents in the PNE group were more likely to make appropriate recommendations regarding work (94% vs 56%), exercise (92% vs 56%), activity (94% vs 67%) and bed rest (69% vs 33%) compared with those in the control group (Pphysiotherapy students, and could be used on a more widespread basis. There is a need to investigate whether these findings can be replicated in other healthcare professions, and how well these reported changes lead to changes in actual clinical behaviour and the clinical outcomes of patients. Copyright © 2017 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  19. An explanation for the universal 3.5 power-law observed in currency markets

    Directory of Open Access Journals (Sweden)

    Nicholas A. Johnson

    Full Text Available We present a mathematical theory to explain a recent empirical finding in the Physics literature (Zhao et al., 2013 in which the distributions of waiting-times between discrete events were found to exhibit power-law tails with an apparent universal exponent: α∼3.5. This new theory provides the first ever qualitative and quantitative explanation of Zhao et al.’s surprising finding. It also provides a mechanistic description of the origin of the observed universality, assigning its cause to the emergence of dynamical feedback processes between evolving clusters of like-minded agents. Keywords: Complex systems, Econophysics, Collective, Power law

  20. Acute motor, neurocognitive and neurophysiological change following concussion injury in Australian amateur football. A prospective multimodal investigation.

    Science.gov (United States)

    Pearce, Alan J; Hoy, Kate; Rogers, Mark A; Corp, Daniel T; Davies, Charlotte B; Maller, Jerome J; Fitzgerald, Paul B

    2015-09-01

    This multimodal study investigated the motor, neurocognitive and neurophysiological responses following a sports related concussion injury in the acute-phase (up to 10 days) in sub-elite Australian football players. Between-group, repeated measures. Over the course of one season (six months), 43 male players from one football club (25.1 ± 4.5 years) were assessed for fine motor dexterity, visuomotor reaction time, implicit learning and attention. Motor cortex excitability and inhibition were assessed using transcranial magnetic stimulation. Of the 43 players, eight suffered concussion injuries, and were compared to 15 non-concussed players (active control) who returned for follow up testing. Post-concussion assessments using the aforementioned tests were carried out at 48 and 96 h, and 10 days. Compared to the non-concussed players, those who suffered concussion showed slowed fine dexterity (P = 0.02), response (P = 0.02) and movement times (P = 0.01) 48 h post-concussion. Similarly, attentional performance was reduced in the concussed group at all time points (48 h: P football players show abnormalities in motor, cognitive and neurophysiological measures with variable rates of recovery. These findings suggest that measuring the recovery of concussed athletes should incorporate a range of testing modalities rather than relying on one area of measurement in determining return to play. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  1. Phase space overpopulation at CERN and possible explanations

    International Nuclear Information System (INIS)

    Pratt, S.

    1998-01-01

    By combining information from correlations from Pb+Pb collisions at CERN, one comes to the conclusion that pionic phase space is significantly overpopulated compared to expectations based on chemical equilibrium. A variety of explanations will be addressed. (author)

  2. The 'side effects' of medicalization: a meta-analytic review of how biogenetic explanations affect stigma.

    Science.gov (United States)

    Kvaale, Erlend P; Haslam, Nick; Gottdiener, William H

    2013-08-01

    Reducing stigma is crucial for facilitating recovery from psychological problems. Viewing these problems biomedically may reduce the tendency to blame affected persons, but critics have cautioned that it could also increase other facets of stigma. We report on the first meta-analytic review of the effects of biogenetic explanations on stigma. A comprehensive search yielded 28 eligible experimental studies. Four separate meta-analyses (Ns=1207-3469) assessed the effects of biogenetic explanations on blame, perceived dangerousness, social distance, and prognostic pessimism. We found that biogenetic explanations reduce blame (Hedges g=-0.324) but induce pessimism (Hedges g=0.263). We also found that biogenetic explanations increase endorsement of the stereotype that people with psychological problems are dangerous (Hedges g=0.198), although this result could reflect publication bias. Finally, we found that biogenetic explanations do not typically affect social distance. Promoting biogenetic explanations to alleviate blame may induce pessimism and set the stage for self-fulfilling prophecies that could hamper recovery from psychological problems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The role of the neurophysiological intraoperative monitoring to prevention of postoperative neurological complication in the surgical treatment of scoliosis

    Directory of Open Access Journals (Sweden)

    M. A. Khit

    2014-01-01

    Full Text Available Bearing in mind that the technique of surgical treatment of scoliosis and skills are high enough, iatrogenic spinal cord injury is still one of the most feared complication of scoliosis surgery. It is well known that the function of the spinal cord may be estimated by combining somatosensory evoked potentials (SSEP and motor evoked potentials (MEP. We have retrospectively evaluated the results of intraoperative neurophysiological monitoring (IOM in a large population of patients underwent surgical treatment of spinal deformity. Intraoperative neuromonitoring SSEP and transcranial electrostimulation (TES – MEP in conjunction with the assessment of the correct position of the screws was performed in 142 consecutive cases, i. e. all patients who had undergone surgical treatment of idiopathic (127 pts, congenital (10 pts or neurogenic (5 pts scoliosis. A neurophysiological “alarm” was defined as a decrease in amplitude (uni- or bilateral of at least 50 % for SEPs and of 70 % for TES-MEP compared with baseline. Total intravenous anesthesia (TIVA in 138 cases was achieved by infusion of propofol (8–16 mg / kg / h and in 4 cases by halogenate anesthesia – sevoflurane (0.4–1.8 MAC. Seven patients (4.9 % were reported intraoperative neurophysiological parameters significant changes that require action by the surgeons and anesthetists, with deterioration of ostoperative neurologic status in one case. Of these three cases, the amplitude drop SSEPs and TESMEPs-was due, to the pharmacological aspects of anesthetic management, in the other four cases – with surgical procedures (response halo-traction – 1 case, mechanical damage of sheath of the spinal cord by pliers Kerrison – 1case, overcorrection – 2 cases. In five cases (3.5 % required reposting of pedicle screws (1–2 levels. Only one patient (0.7 % had a persistent postoperative neurological disorder (neuropathic pain, respectively from a level of re-reposition of

  4. Sugammadex to reverse neuromuscular blockade and provide optimal conditions for motor-evoked potential monitoring

    Directory of Open Access Journals (Sweden)

    Mehdi Trifa

    2017-01-01

    Full Text Available Sugammadex is a novel pharmacologic agent, which reverses neuromuscular blockade (NMB via a mechanism that differs completely from acetylcholinesterase inhibitors. By encapsulating rocuronium, sugammadex can provide recovery of neuromuscular function even when there is a profound degree of NMB. We report anecdotal experience with the use of sugammadex to reverse NMB to facilitate intraoperative neurophysiological monitoring (motor evoked potentials in an adolescent with scoliosis during posterior spinal fusion. Its potential application in this unique clinical scenario is discussed, and potential dosing schemes are reviewed.

  5. An Explanation of True Dreams: Aristotle and Jung

    Directory of Open Access Journals (Sweden)

    Ali Sanai

    2016-12-01

    Full Text Available The naturalistic explanation of realized dream (or dreams that come true means that this phenomen will be explained regardless of supernatural agents. Aristotle in Parva naturalia and Jung in his works explained dream visionary. In this article by scrutiny on these thinkers’ theory, we will indicate the naturalistic approach to dream that is far- fetched for followers of metaphysics. In spite of this fact that Aristotle and Jung both belongs to different historical contexts, they have common aspects in terms of naturalistic method; in the universal or broad sense of word, but in terms of content both explain the true dream by the term “coincidence” or accidental conformity between objective events and psychological affairs. It also seems that the notion of Neutral monism in Jung is adaptive to Hylomorphism in Aristotle psychology, and this, provides a path for naturalistic approach to dream as one forms of consciousness.

  6. Neurophysiological Pain-education for Patients with Chronic Low Back Pain - A Systematic Review and Meta-analysis

    DEFF Research Database (Denmark)

    Tegner, Heidi; Frederiksen, Pernille; Esbensen, Bente Appel

    2018-01-01

    OBJECTIVE: To evaluate the effect of Neurophysiological Pain-Education (NPE) for patients with Chronic Low Back Pain (CLBP). METHODS: A systematic search was performed in six electronic databases. Eligible RCTs were those with at least 50 % of patients with CLBP and in which NPE was compared...... with no intervention or usual care. Methodological quality was assessed independently by two of the authors using the Cochrane Collaboration Risk of Bias Tool. The effect of NPE was summarized in a random effect meta-analysis for pain, disability and behavioral attitudes. Effect was estimated as weighted mean...

  7. What Do Students' Explanations Look Like When They Use Second-Hand Data?

    Science.gov (United States)

    Delen, Ibrahim; Krajcik, Joseph

    2015-01-01

    Explanation studies underlined the importance of using evidence in support of claims. However, few studies have focused on students' use of others' data (second-hand data) in this process. In this study, students collected data from a local water source and then took all the data back to the classroom to create scientific explanations by using…

  8. Neurophysiological Correlates of Various Mental Perspectives

    Directory of Open Access Journals (Sweden)

    Thilo eHinterberger

    2014-08-01

    Full Text Available A common view of consciousness is that our mind presents emotions, experiences and images in an internal mental (re-presentation space which in a state of wakefulness is triggered by the world outside. Consciousness can be defined as the observation of this inner mental space. We propose a new model, in which the state of the conscious observer is defined by the observer’s mental position and focus of attention. The mental position of the observer can either be within the mental self (intrapersonal space, in the mental outer world (extrapersonal space or in an empathic connection, i.e. within the intrapersonal space of another person (perspective taking. The focus of attention can be directed towards the self or towards the outside world. This mental space model can help us to understand the patterns of relationships and interactions with other persons as they occur in social life.To investigate the neurophysiological correlates and discriminability of the different mental states, we conducted an EEG experiment measuring the brain activity of 16 subjects via 64 electrodes while they engaged in different mental positions (intrapersonal, extrapersonal, perspective taking with different attentional foci (self, object. Compared to external mental locations, internal ones showed significantly increased alpha2 power, especially when the observer was focusing on an object. Alpha2 and beta2 were increased in the empathic condition compared to the extrapersonal perspective. Delta power was significantly higher when the attentional focus was directed towards an object in comparison to the participant’s own self. This exploratory study demonstrates highly significant differences between various mental locations and foci, suggesting that the proposed categories of mental location and intra- and interpersonal attentional foci are not only helpful theoretical concepts but are also physiologically relevant and therefore may relate to basic brain processing

  9. 75 FR 75453 - Proposed Information Collection; Comment Request; Technical Data Letter of Explanation

    Science.gov (United States)

    2010-12-03

    ... Request; Technical Data Letter of Explanation AGENCY: Bureau of Industry and Security. ACTION: Notice....gov . SUPPLEMENTARY INFORMATION: I. Abstract These technical data letters of explanation will assure the Bureau of Industry and Security that U.S.-origin technical data will be exported only for...

  10. Theoretical explanations for maintenance of behaviour change: a systematic review of behaviour theories.

    Science.gov (United States)

    Kwasnicka, Dominika; Dombrowski, Stephan U; White, Martin; Sniehotta, Falko

    2016-09-01

    Behaviour change interventions are effective in supporting individuals in achieving temporary behaviour change. Behaviour change maintenance, however, is rarely attained. The aim of this review was to identify and synthesise current theoretical explanations for behaviour change maintenance to inform future research and practice. Potentially relevant theories were identified through systematic searches of electronic databases (Ovid MEDLINE, Embase, PsycINFO). In addition, an existing database of 80 theories was searched, and 25 theory experts were consulted. Theories were included if they formulated hypotheses about behaviour change maintenance. Included theories were synthesised thematically to ascertain overarching explanations for behaviour change maintenance. Initial theoretical themes were cross-validated. One hundred and seventeen behaviour theories were identified, of which 100 met the inclusion criteria. Five overarching, interconnected themes representing theoretical explanations for behaviour change maintenance emerged. Theoretical explanations of behaviour change maintenance focus on the differential nature and role of motives, self-regulation, resources (psychological and physical), habits, and environmental and social influences from initiation to maintenance. There are distinct patterns of theoretical explanations for behaviour change and for behaviour change maintenance. The findings from this review can guide the development and evaluation of interventions promoting maintenance of health behaviours and help in the development of an integrated theory of behaviour change maintenance.

  11. Intelligence and Neurophysiological Markers of Error Monitoring Relate to Children's Intellectual Humility.

    Science.gov (United States)

    Danovitch, Judith H; Fisher, Megan; Schroder, Hans; Hambrick, David Z; Moser, Jason

    2017-09-18

    This study explored developmental and individual differences in intellectual humility (IH) among 127 children ages 6-8. IH was operationalized as children's assessment of their knowledge and willingness to delegate scientific questions to experts. Children completed measures of IH, theory of mind, motivational framework, and intelligence, and neurophysiological measures indexing early (error-related negativity [ERN]) and later (error positivity [Pe]) error-monitoring processes related to cognitive control. Children's knowledge self-assessment correlated with question delegation, and older children showed greater IH than younger children. Greater IH was associated with higher intelligence but not with social cognition or motivational framework. ERN related to self-assessment, whereas Pe related to question delegation. Thus, children show separable epistemic and social components of IH that may differentially contribute to metacognition and learning. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  12. Neurophysiology of spectrotemporal cue organization of spoken language in auditory memory.

    Science.gov (United States)

    Moberly, Aaron C; Bhat, Jyoti; Welling, D Bradley; Shahin, Antoine J

    2014-03-01

    Listeners assign different weights to spectral dynamics, such as formant rise time (FRT), and temporal dynamics, such as amplitude rise time (ART), during phonetic judgments. We examined the neurophysiological basis of FRT and ART weighting in the /ba/-/wa/ contrast. Electroencephalography was recorded for thirteen adult English speakers during a mismatch negativity (MMN) design using synthetic stimuli: a /ba/ with /ba/-like FRT and ART; a /wa/ with /wa/-like FRT and ART; and a /ba/(wa) with /ba/-like FRT and /wa/-like ART. We hypothesized that because of stronger reliance on FRT, subjects would encode a stronger memory trace and exhibit larger MMN during the FRT than the ART contrast. Results supported this hypothesis. The effect was most robust in the later portion of MMN. Findings suggest that MMN is generated by multiple sources, differentially reflecting acoustic change detection (earlier MMN, bottom-up process) and perceptual weighting of ART and FRT (later MMN, top-down process). Copyright © 2014 Elsevier Inc. All rights reserved.

  13. The Improvement of Simple Explanation and Inferencetion Skills with Problem Solving

    OpenAIRE

    Dewanti, Fransiska Olivia; Diawati, Chansyanah; Fadiawati, Noor

    2013-01-01

    The learning process is strongly influenced by the ability and accuracy of teachers in selecting and applying the learning model. The model can be applied to improve of  simple explanation and inferencetion skill is a model of problem solving. The purpose of this study was to describe the model of problem solving that are effective in improving simple explanation and inferencetion skills on the material electrolyte and non-electrolyte solution. This research use a quasi-experimental methods ...

  14. Neurophysiologic intraoperative monitoring of the vestibulocochlear nerve.

    Science.gov (United States)

    Simon, Mirela V

    2011-12-01

    Neurosurgical procedures involving the skull base and structures within can pose a significant risk of damage to the brain stem and cranial nerves. This can have life-threatening consequences and/or result in devastating neurologic deficits. Over the past decade, intraoperative neurophysiology has significantly evolved and currently offers a great tool for live monitoring of the integrity of nervous structures. Thus, dysfunction can be identified early and prompt modification of the surgical management or operating conditions, leads to avoidance of permanent structural damage.Along these lines, the vestibulocochlear nerve (CN VIII) and, to a greater extent, the auditory pathways as they pass through the brain stem are especially at risk during cerebelopontine angle (CPA), posterior/middle fossa, or brain stem surgery. CN VIII can be damaged by several mechanisms, from vascular compromise to mechanical injury by stretch, compression, dissection, and heat injury. Additionally, cochlea itself can be significantly damaged during temporal bone drilling, by noise, mechanical destruction, or infarction, and because of rupture, occlusion, or vasospasm of the internal auditory artery.CN VIII monitoring can be successfully achieved by live recording of the function of one of its parts, the cochlear or auditory nerve (AN), using the brain stem auditory evoked potentials (BAEPs), electrocochleography (ECochG), and compound nerve action potentials (CNAPs) of the cochlear nerve.This is a review of these techniques, their principle, applications, methodology, interpretation of the evoked responses, and their change from baseline, within the context of surgical and anesthesia environments, and finally the appropriate management of these changes.

  15. 32 CFR 516.3 - Explanation of abbreviations and terms.

    Science.gov (United States)

    2010-07-01

    ... Glossary contains explanations of abbreviations and terms. (b) The masculine gender has been used throughout this regulation for simplicity and consistency. Any reference to the masculine gender is intended...

  16. Learning the Language of Evolution: Lexical Ambiguity and Word Meaning in Student Explanations

    Science.gov (United States)

    Rector, Meghan A.; Nehm, Ross H.; Pearl, Dennis

    2013-01-01

    Our study investigates the challenges introduced by students' use of lexically ambiguous language in evolutionary explanations. Specifically, we examined students' meaning of five key terms incorporated into their written evolutionary explanations: "pressure", "select", "adapt", "need", and "must". We utilized a new technological tool known as the…

  17. Investigating the Development of Chinese Oral Explanation and Justification in Singapore Primary Students

    Science.gov (United States)

    Yan, Jing

    2016-01-01

    Explanation and justification require cognitive ability which selects and organises relevant information in a logical way, and linguistic ability which enables speakers to encode the information with linguistic knowledge. This study aims to investigate the development of Chinese oral explanation and justification in Singapore primary students. The…

  18. Phase space overpopulation at CERN and possible explanations

    International Nuclear Information System (INIS)

    Pratt, S.

    1999-01-01

    Complete text of publication follows. By combining information from correlations from Pb+Pb collisions at CERN, one comes to the conclusion that pionic phase space is significantly overpopulated compared to expectations based on chemical equilibrium. A variety of explanations will be addressed. (author)

  19. Sex Differences in Social Behavior: Are the Social Role and Evolutionary Explanations Compatible?

    Science.gov (United States)

    Archer, John

    1996-01-01

    Examines competing claims of two explanations of sex differences in social behavior, social role theory, and evolutionary psychology. Findings associated with social role theory are weighed against evolutionary explanations. It is suggested that evolutionary theory better accounts for the overall pattern of sex differences and for their origins.…

  20. Neurophysiological capacity in a working memory task differentiates dependent from nondependent heavy drinkers and controls.

    Science.gov (United States)

    Wesley, Michael J; Lile, Joshua A; Fillmore, Mark T; Porrino, Linda J

    2017-06-01

    Determining the neurobehavioral profiles that differentiate heavy drinkers who are and are not alcohol dependent will inform treatment efforts. Working memory is linked to substance use disorders and can serve as a representation of the demand placed on the neurophysiology associated with cognitive control. Behavior and brain activity (via fMRI) were recorded during an N-Back working memory task in controls (CTRL), nondependent heavy drinkers (A-ND) and dependent heavy drinkers (A-D). Typical and novel step-wise analyses examined profiles of working memory load and increasing task demand, respectively. Performance was significantly decreased in A-D during high working memory load (2-Back), compared to CTRL and A-ND. Analysis of brain activity during high load (0-Back vs. 2- Back) showed greater responses in the dorsal lateral and medial prefrontal cortices of A-D than CTRL, suggesting increased but failed compensation. The step-wise analysis revealed that the transition to Low Demand (0-Back to 1-Back) was associated with robust increases and decreases in cognitive control and default-mode brain regions, respectively, in A-D and A-ND but not CTRL. The transition to High Demand (1-Back to 2-Back) resulted in additional engagement of these networks in A-ND and CTRL, but not A-D. Heavy drinkers engaged working memory neural networks at lower demand than controls. As demand increased, nondependent heavy drinkers maintained control performance but relied on additional neurophysiological resources, and dependent heavy drinkers did not display further resource engagement and had poorer performance. These results support targeting these brain areas for treatment interventions. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Invertebrate neuroscience and CephsInAction at the Mediterranean Society for Neuroscience Meeting Cagliari 2015.

    Science.gov (United States)

    Holden-Dye, Lindy; Fiorito, Graziano; Ponte, Giovanna

    2015-12-01

    Invertebrate neuroscience, and in particular cephalopod research, is well represented in the Mediterranean region. Therefore, the recent meeting of the Mediterranean Society for Neuroscience in Santa Margherita di Pula, Sardinia (12-15 June 2015) provided an excellent opportunity for invertebrate contributions. Furthermore, the Chair of an EU COST Action for cephalopod research (FA1301; www.cephsinaction.org ), Giovanna Ponte, together with Graziano Fiorito from the Stazione Zoologica, Naples, aligned a meeting of research groups working in the field of cephalopod neurophysiology from across Europe to coincide with the neuroscience meeting. This provided an exciting forum for exchange of ideas. Here we provide brief highlights of both events and an explanation of the activities of the COST Action for the broader invertebrate neuroscience community.

  2. A Self-Categorization Explanation for Opinion Consensus Perceptions

    Science.gov (United States)

    Zhang, Jinguang; Reid, Scott A.

    2013-01-01

    The public expression of opinions (and related communicative activities) hinges upon the perception of opinion consensus. Current explanations for opinion consensus perceptions typically focus on egocentric and other biases, rather than functional cognitions. Using self-categorization theory we showed that opinion consensus perceptions flow from…

  3. A Critical Test of Self-Enhancement, Exposure, and Self-Categorization Explanations for First- and Third-Person Perceptions

    Science.gov (United States)

    Reid, Scott A.; Byrne, Sahara; Brundidge, Jennifer S.; Shoham, Mirit D.; Marlow, Mikaela L.

    2007-01-01

    The third-person perception is the tendency for people to believe that others are more influenced by media content than themselves (W. P. Davison, 1983). The current study provides a critical test of self-enhancement, exposure, and self-categorization explanations for first- (i.e., self more influenced than others) and third-person perceptions.…

  4. Neurophysiological evidence of impaired self-monitoring in schizotypal personality disorder and its reversal by dopaminergic antagonism.

    Science.gov (United States)

    Rabella, Mireia; Grasa, Eva; Corripio, Iluminada; Romero, Sergio; Mañanas, Miquel Àngel; Antonijoan, Rosa M; Münte, Thomas F; Pérez, Víctor; Riba, Jordi

    2016-01-01

    Schizotypal personality disorder (SPD) is a schizophrenia-spectrum disorder characterized by odd or bizarre behavior, strange speech, magical thinking, unusual perceptual experiences, and social anhedonia. Schizophrenia proper has been associated with anomalies in dopaminergic neurotransmission and deficits in neurophysiological markers of self-monitoring, such as low amplitude in cognitive event-related brain potentials (ERPs) like the error-related negativity (ERN), and the error positivity (Pe). These components occur after performance errors, rely on adequate fronto-striatal function, and are sensitive to dopaminergic modulation. Here we postulated that analogous to observations in schizophrenia, SPD individuals would show deficits in self-monitoring, as measured by the ERN and the Pe. We also assessed the capacity of dopaminergic antagonists to reverse these postulated deficits. We recorded the electroencephalogram (EEG) from 9 SPD individuals and 12 healthy controls in two separate experimental sessions while they performed the Eriksen Flanker Task, a classical task recruiting behavioral monitoring. Participants received a placebo or 1 mg risperidone according to a double-blind randomized design. After placebo, SPD individuals showed slower reaction times to hits, longer correction times following errors and reduced ERN and Pe amplitudes. While risperidone impaired performance and decreased ERN and Pe in the control group, it led to behavioral improvements and ERN amplitude increases in the SPD individuals. These results indicate that SPD individuals show deficits in self-monitoring analogous to those in schizophrenia. These deficits can be evidenced by neurophysiological measures, suggest a dopaminergic imbalance, and can be reverted by dopaminergic antagonists.

  5. Theoretical explanations for maintenance of behaviour change: a systematic review of behaviour theories

    Science.gov (United States)

    Kwasnicka, Dominika; Dombrowski, Stephan U; White, Martin; Sniehotta, Falko

    2016-01-01

    ABSTRACT Background: Behaviour change interventions are effective in supporting individuals in achieving temporary behaviour change. Behaviour change maintenance, however, is rarely attained. The aim of this review was to identify and synthesise current theoretical explanations for behaviour change maintenance to inform future research and practice. Methods: Potentially relevant theories were identified through systematic searches of electronic databases (Ovid MEDLINE, Embase, PsycINFO). In addition, an existing database of 80 theories was searched, and 25 theory experts were consulted. Theories were included if they formulated hypotheses about behaviour change maintenance. Included theories were synthesised thematically to ascertain overarching explanations for behaviour change maintenance. Initial theoretical themes were cross-validated. Findings: One hundred and seventeen behaviour theories were identified, of which 100 met the inclusion criteria. Five overarching, interconnected themes representing theoretical explanations for behaviour change maintenance emerged. Theoretical explanations of behaviour change maintenance focus on the differential nature and role of motives, self-regulation, resources (psychological and physical), habits, and environmental and social influences from initiation to maintenance. Discussion: There are distinct patterns of theoretical explanations for behaviour change and for behaviour change maintenance. The findings from this review can guide the development and evaluation of interventions promoting maintenance of health behaviours and help in the development of an integrated theory of behaviour change maintenance. PMID:26854092

  6. An Explanation for the Arctic Sea Ice Melt Pond Fractal Transition

    Science.gov (United States)

    Popovic, P.; Abbot, D. S.

    2016-12-01

    As Arctic sea ice melts during the summer, pools of melt water form on its surface. This decreases the ice's albedo, which signifcantly impacts its subsequent evolution. Understanding this process is essential for buiding accurate sea ice models in GCMs and using them to forecast future changes in sea ice. A feature of melt ponds that helps determine their impact on ice albedo is that they often form complex geometric shapes. One characteristic of their shape, the fractal dimension of the pond boundaries, D, has been shown to transition between the two fundamental limits of D = 1 and D = 2 at some critical pond size. Here, we provide an explanation for this behavior. First, using aerial photographs taken during the SHEBA mission, we show how this fractal transition curve changes with time, and show that there is a qualitative difference in the pond shape as ice transitions from impermeable to permeable. While ice is impermeable, the maximum fractal dimension is less than 2, whereas after it becomes permeable, the maximum fractal dimension becomes very close to 2. We then show how the fractal dimension of the boundary of a collection of overlapping circles placed randomly on a plane also transitions from D = 1 to D = 2 at a size equal to the average size of a single circle. We, therefore, conclude that this transition is a simple geometric consequence of regular shapes connecting. The one physical parameter that can be extracted from the fractal transition curve is the length scale at which transition occurs. Previously, this length scale has been associated with the typical size of snow dunes created on the ice surface during winter. We provide an alternative explanation by noting that the flexural wavelength of the ice poses a fundamental limit on the size of melt ponds on permeable ice. If this is true, melt ponds could be used as a proxy for ice thickness. Finally, we provide some remarks on how to observationally distinguish between the two ideas for what

  7. Neurophysiological and behavioral responses to music therapy in vegetative and minimally conscious states

    DEFF Research Database (Denmark)

    O'Kelly, Julian; James, L.; Palaniappan, R.

    2013-01-01

    for preferred music (p = 0.029) across the VS cohort. Two VS cases are presented with concurrent changes (p ≤ 0.05) across measures indicative of discriminatory responses to both music therapy procedures. A MCS case study highlights how more sensitive selective attention may distinguish MCS from VS. Further...... of musical stimuli on arousal, attention and emotion, irrespective of verbal or motor deficits, however, an evidence base is lacking. To address this, a neurophysiological and behavioural study was undertaken comparing EEG, heart rate variability, respiration and behavioural responses of 20 healthy subjects...... responses (p ≤ 0.05) across healthy subjects corresponding to arousal and attention in response to preferred music including concurrent increases in respiration rate with globally enhanced EEG power spectra responses across frequency bandwidths. Whilst physiological responses were heterogeneous across...

  8. Competing explanations for adopting energy innovations for new office buildings

    International Nuclear Information System (INIS)

    Vermeulen, Walter J.V.; Hovens, Jeroen

    2006-01-01

    An integrative model to explain potential adopters' decisions to adopt energy innovations was adapted and applied in the field of new office building construction. We tested the relative effects of competing theoretical explanations (derived from economics, innovation science and policy science) on the decision to adopt. The research covered 35 projects representing 9% of the total volume of new office construction in the Netherlands between 2000 and mid-2002. Two levels of explanations for adopting innovations were derived: (a) the potential adopter's weighed assessments of the innovations and his or her nature of decision making and (b) explanation of those first-level variables. Using multiple regression techniques, we determined the relative influence on innovation-adoption of variables covering economy and technology, government intervention, company characteristics, and influences from market and society. The decision to adopt 'mature' innovations, in contrast to 'young' innovations, is based more on routine procedures than project-specific considerations. Policies need to take this difference into consideration. We also show evidence that in promoting adoption of E-innovations for new office buildings the Dutch system of applying Energy Performance Standards and subsidies proofs to be effective

  9. Infant Preferences for Attractive Faces: A Cognitive Explanation.

    Science.gov (United States)

    Rubenstein, Adam J.; Kalakanis, Lisa; Langlois, Judith H.

    1999-01-01

    Four studies assessed a cognitive explanation for development of infants' preference for attractive faces: cognitive averaging and preferences for mathematically averaged faces, or prototypes. Findings indicated that adults and 6-month olds prefer prototypical, mathematically averaged faces and that 6-month olds can abstract the central tendency…

  10. Psychosocial explanations of complaints in Dutch general practice

    NARCIS (Netherlands)

    Joosten, A; Mazeland, H; Meyboom-de Jong, B

    BACKGROUND: Dutch GPs are frequently consulted by patients presenting physical complaints which have a psychosocial cause. Until now, this type of complaint has often been the subject of study, but the way in which psychosocial explanations for complaints are broached and discussed has not yet been

  11. A flat space-time relativistic explanation for the perihelion advance of Mercury

    OpenAIRE

    Behera, Harihar; Naik, P. C.

    2003-01-01

    Starting with the flat space-time relativistic versions of Maxwell-Heaviside's toy model vector theory of gravity and introducing the gravitational analogues for the electromagnetic Lienard-Wiechert potentials together with the notion of a gravitational Thomas Precession; the observed anomalous perihelion advance of Mercury's orbit is here explained as a relativistic effect in flat (Minkowski) space-time, unlike Einstein's curved space-time relativistic explanation. In this new explanation fo...

  12. Prediction and explanation over DL-Lite data streams

    CSIR Research Space (South Africa)

    Klarman, S

    2013-12-01

    Full Text Available the popular DL-Lite family, and study the logic foundations of prediction and explanation over DL-Lite data streams, i.e., reasoning from finite segments of streaming data to conjectures about the content of the streams in the future or in the past. We propose...

  13. Biogenetic explanations and stigma: a meta-analytic review of associations among laypeople.

    Science.gov (United States)

    Kvaale, Erlend P; Gottdiener, William H; Haslam, Nick

    2013-11-01

    The stigma and social rejection faced by people with a mental disorder constitute a major barrier to their well-being and recovery. Medicalization has been welcomed as a strategy to reduce blame and stigma, although critics have cautioned that attributing mental disorders to biogenetic causes may have unintended side effects that could exacerbate prejudice and rejection. The present study presents a quantitative synthesis of the literature on relationships between biogenetic explanations for mental disorders and three key elements of stigma, namely blame, perceptions of dangerousness, and social distance. A comprehensive search yielded 25 studies meeting the inclusion criteria. Separate meta-analyses (Ns = 4278-23,816) were conducted for the three stigma types, and assessed the consistency of effects across subgroups of studies involving different types of biogenetic explanations, mental disorders, and samples. We found that people who hold biogenetic explanations for mental disorders tend to blame affected persons less for their problems (r = -0.19), but perceive them as more dangerous (r = 0.09) and desire more distance from them (r = 0.05). The negative association with blame was significant for schizophrenia, belief in genetic causation, and in student samples. The positive association with dangerousness was significant for all disorders, belief in general biogenetic causation, and in community samples. The positive association with social distance was significant for schizophrenia, beliefs in neurochemical and general biogenetic causation, and in community samples. Nevertheless, across all analyses, biogenetic explanations were only weakly related to stigma. We conclude that biogenetic explanations for mental disorders confer mixed blessings for stigma. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Taste, Salt Consumption, and Local Explanations around Hypertension in a Rural Population in Northern Peru

    OpenAIRE

    Pesantes, M. Amalia; Diez-Canseco, Francisco; Bernab?-Ortiz, Antonio; Ponce-Lucero, Vilarmina; Miranda, J. Jaime

    2017-01-01

    Interventions to promote behaviors to reduce sodium intake require messages tailored to local understandings of the relationship between what we eat and our health. We studied local explanations about hypertension, the relationship between local diet, salt intake, and health status, and participants? opinions about changing food habits. This study provided inputs for a social marketing campaign in Peru promoting the use of a salt substitute containing less sodium than regular salt. Qualitativ...

  15. Causal explanations of distress and general practitioners' assessments of common mental disorder among punjabi and English attendees.

    Science.gov (United States)

    Bhui, Kamaldeep; Bhugra, Dinesh; Goldberg, David

    2002-01-01

    The literature on the primary care assessment of mental distress among Indian subcontinent origin patients suggests frequent presentations to general practitioner, but rarely for recognisable psychiatric disorders. This study investigates whether cultural variations in patients' causal explanatory models account for cultural variations in the assessment of non-psychotic mental disorders in primary care. In a two-phase survey, 272 Punjabi and 269 English subjects were screened. The second phase was completed by 209 and 180 subjects, respectively. Causal explanatory models were elicited as explanations of two vignette scenarios. One of these emphasised a somatic presentation and the other anxiety symptoms. Psychiatric disorder was assessed by GPs on a Likert scale and by a psychiatrist on the Clinical Interview Schedule. Punjabis more commonly expressed medical/somatic and religious beliefs. General practitioners were more likely to assess any subject giving psychological explanations to vignette A and English subjects giving religious explanations to vignette B as having a significant psychiatric disorder. Where medical/somatic explanations of distress were most prevalent in response to the somatic vignette, psychological, religious and work explanations were less prevalent among Punjabis but not among English subjects. Causal explanations did not fully explain cultural differences in assessments. General practitioners' assessments and causal explanations are related and influenced by culture, but causal explanations do not fully explain cultural differences in assessments.

  16. Investigating neurophysiological correlates of metacontrast masking with magnetoencephalography

    Directory of Open Access Journals (Sweden)

    Jens Schwarzbach

    2006-01-01

    Full Text Available Early components of visual evoked potentials (VEP in EEG seem to be unaffected by target visibility in visual masking studies. Bridgeman's reanalysis of Jeffreys and Musselwhite's (1986 data suggests that a later visual component in the VEP, around 250 ms reflects the perceptual effect of masking. We challenge this view on the ground that temporal interactions between targets and masks unrelated to stimulus visibility could account for Bridgeman's observation of a U-shaped time course in VEP amplitudes for this later component. In an MEG experiment of metacontrast masking with variable stimulus onset asynchrony, we introduce a proper control, a pseudo mask. In contrast to an effective mask, the pseudomask should produce neither behavioral masking nor amplitude modulations of late VEPs. Our results show that effective masks produced a strong U-shaped perceptual effect of target visibility while performance remained virtually perfect when a pseudomask was used. The visual components around 250 ms after target onset did not show a distinction between mask and pseudomask conditions. The results indicate that these visual evoked potentials do not reveal neurophysiological correlates of stimulus visibility but rather reflect dynamic interactions between superimposed potentials elicited by stimuli in close temporal proximity. However, we observed a postperceptual component around 340 ms after target onset, located over temporal-parietal cortex, which shows a clear effect of visibility. Based on P300 ERP literature, this finding could indicate that working memory related processes contribute to metacontrast masking.

  17. The musical brain: brain waves reveal the neurophysiological basis of musicality in human subjects.

    Science.gov (United States)

    Tervaniemi, M; Ilvonen, T; Karma, K; Alho, K; Näätänen, R

    1997-04-18

    To reveal neurophysiological prerequisites of musicality, auditory event-related potentials (ERPs) were recorded from musical and non-musical subjects, musicality being here defined as the ability to temporally structure auditory information. Instructed to read a book and to ignore sounds, subjects were presented with a repetitive sound pattern with occasional changes in its temporal structure. The mismatch negativity (MMN) component of ERPs, indexing the cortical preattentive detection of change in these stimulus patterns, was larger in amplitude in musical than non-musical subjects. This amplitude enhancement, indicating more accurate sensory memory function in musical subjects, suggests that even the cognitive component of musicality, traditionally regarded as depending on attention-related brain processes, in fact, is based on neural mechanisms present already at the preattentive level.

  18. The Effects of Two Reality Explanations on Children's Reactions to a Frightening Movie Scene.

    Science.gov (United States)

    Wilson, Barbara J.; Weiss, Audrey J.

    1991-01-01

    Assesses the effectiveness of two reality explanations on children's reactions to frightening programs. Shows that neither influenced younger children's emotional or cognitive reactions, whereas the special tricks explanation reduced older children's emotional responses with no impact on their interpretation. Shows that the real life explanation…

  19. Towards real-time communication between in vivo neurophysiological data sources and simulator-based brain biomimetic models.

    Science.gov (United States)

    Lee, Giljae; Matsunaga, Andréa; Dura-Bernal, Salvador; Zhang, Wenjie; Lytton, William W; Francis, Joseph T; Fortes, José Ab

    2014-11-01

    Development of more sophisticated implantable brain-machine interface (BMI) will require both interpretation of the neurophysiological data being measured and subsequent determination of signals to be delivered back to the brain. Computational models are the heart of the machine of BMI and therefore an essential tool in both of these processes. One approach is to utilize brain biomimetic models (BMMs) to develop and instantiate these algorithms. These then must be connected as hybrid systems in order to interface the BMM with in vivo data acquisition devices and prosthetic devices. The combined system then provides a test bed for neuroprosthetic rehabilitative solutions and medical devices for the repair and enhancement of damaged brain. We propose here a computer network-based design for this purpose, detailing its internal modules and data flows. We describe a prototype implementation of the design, enabling interaction between the Plexon Multichannel Acquisition Processor (MAP) server, a commercial tool to collect signals from microelectrodes implanted in a live subject and a BMM, a NEURON-based model of sensorimotor cortex capable of controlling a virtual arm. The prototype implementation supports an online mode for real-time simulations, as well as an offline mode for data analysis and simulations without real-time constraints, and provides binning operations to discretize continuous input to the BMM and filtering operations for dealing with noise. Evaluation demonstrated that the implementation successfully delivered monkey spiking activity to the BMM through LAN environments, respecting real-time constraints.

  20. Understanding the generative capacity of analogies as a tool for explanation

    Science.gov (United States)

    Wong, E. David

    1993-12-01

    Psychological studies have typically portrayed analogical reasoning as a process of schema transfer from a familiar domain of understanding to a problem situation. These studies have usually examined analogical reasoning in contexts where (a) individuals possess or have been provided with appropriate, problem-specific schema, (b) the nature of the problem and/or solution is fairly well defined, and (c) ideal analogies are provided or suggested by an outside source. This study examines analogical reasoning in contexts where understanding is generated from loosely organized, incomplete prior knowledge rather than transferred from a well-structured domain of understanding. In addition, participants were asked to create, apply, and modify their own analogies - as opposed to applying a given analogy - as a heuristic for constructing, evaluating, and modifying their explanations for a particular scientific phenomena. The results provide empirical support for the generative properties of analogies; that is, analogies can stimulate new inferences and insight. Furthermore, under specific conditions, individuals can productively harness the generative capacity of their own analogies to advance their conceptual understanding of scientific phenomena.

  1. Exogenous Cortisol Administration; Effects on Risk Taking Behavior, Exercise Performance, and Physiological and Neurophysiological Responses.

    Science.gov (United States)

    Robertson, Caroline V; Immink, Maarten A; Marino, Frank E

    2016-01-01

    Rationale: Exogenous cortisol is a modulator of behavior related to increased motivated decision making (Putman et al., 2010), where risky choices yield potentially big reward. Making risk based judgments has been shown to be important to athletes in optimizing pacing during endurance events (Renfree et al., 2014; Micklewright et al., 2015). Objectives: Therefore, the aims of this study were to examine the effect of 50 mg exogenous cortisol on neurophysiological responses and risk taking behavior in nine healthy men. Further to this, to examine the effect of exogenous cortisol on exercise performance. Methods: Using a double blind counterbalanced design, cyclists completed a placebo (PLA), and a cortisol (COR) trial (50 mg cortisol), with drug ingestion at 0 min. Each trial consisted of a rest period from 0 to 60 min, followed by a risk taking behavior task, a 30 min time trial (TT) with 5 × 30 s sprints at the following time intervals; 5, 11, 17, 23, and 29 min. Salivary cortisol (SaCOR), Electroencephalography (EEG) and Near Infrared Spectroscopy (NIRs) were measured at 15, 30, 45, and 60 min post-ingestion. Glucose and lactate samples were taken at 0 and 60 min post-ingestion. During exercise, power output (PO), heart rate (HR), EEG, and NIRS were measured. SaCOR was measured 10 min post-exercise. Results: Cortisol increased risk taking behavior from baseline testing. This was in line with significant neurophysiological changes at rest and during exercise. At rest, SaCOR levels were higher ( P exogenous cortisol on exercise performance. These results are in line with previous research showing altered risk taking behavior following exogenous cortisol, however the altered behavior did not translate into changes in exercise performance.

  2. Preventing lower cranial nerve injuries during fourth ventricle tumor resection by utilizing intraoperative neurophysiological monitoring.

    Science.gov (United States)

    Jahangiri, Faisal R; Minhas, Mazhar; Jane, John

    2012-12-01

    We present two cases illustrating the benefit of utilizing intraoperative neurophysiological monitoring (IONM) for prevention of injuries to the lower cranial nerves during fourth ventricle tumor resection surgeries. Multiple cranial nerve nuclei are located on the floor of the fourth ventricle with a high risk of permanent damage. Two male patients (ages 8 and 10 years) presented to the emergency department and had brain magnetic resonance imaging (MRI) scans showing brainstem/fourth ventricle tumors. During surgery, bilateral posterior tibial and median nerve somatosensory evoked potentials (SSEPs); four-limb and cranial nerves transcranial electrical motor evoked potentials (TCeMEPs); brainstem auditory evoked responses (BAERs); and spontaneous electromyography (s-EMG) were recorded. Electromyography (EMG) was monitored bilaterally from cranial nerves V VII, IX, X, XI, and XII. Total intravenous anesthesia was used. Neuromuscular blockade was used only for initial intubation. Pre-incision baselines were obtained with good morphology of waveforms. After exposure the floor of the fourth ventricle was mapped by triggered-EMG (t-EMG) using 0.4 to 1.0 mA. In both patients the tumor was entangled with cranial nerves VII to XII on the floor of the fourth ventricle. The surgeon made the decision not to resect the tumor in one case and limited the resection to 70% of the tumor in the second case on the basis of neurophysiological monitoring. This decision was made to minimize any post-operative neurological deficits due to surgical manipulation of the tumor involving the lower cranial nerves. Intraoperative spontaneous and triggered EMG was effectively utilized in preventing injuries to cranial nerves during surgical procedures. All signals remained stable during the surgical procedure. Postoperatively both patients were well with no additional cranial nerve weakness. At three months follow-up, the patients continued to have no deficits.

  3. Older persons' definitions and explanations of elder abuse in the Netherlands.

    Science.gov (United States)

    Mysyuk, Yuliya; Westendorp, Rudi G J; Lindenberg, Jolanda

    2016-01-01

    In this article we explore older persons' definitions of and explanations for elder abuse in the Netherlands by means of interviews with older persons. A qualitative study was conducted based on semistructured interviews with 35 older persons who had no experience with abuse. Our findings show that older persons participating in our study define elder abuse foremost as physical violence that is performed intentionally. The study participants explain elder abuse as a result of the dependency and vulnerability of older persons, of changing norms and values, and of changes in the position of older persons in society, which result in disrespect toward older persons and a lack of social control and responsibility. The older persons' explanations for the occurrence of abuse mainly focus on societal changes; older persons seem to regard elder abuse primarily as a societal problem. This understanding of, and explanation for, elder abuse may influence their detection and reporting behavior, as they may tend to acknowledge only severe cases of intentional physical violence that leave clear and therefore physically detectable evidence.

  4. Practitioner and client explanations for disparities in health care use between migrant and non-migrant groups in Sweden: a qualitative study.

    Science.gov (United States)

    Akhavan, Sharareh; Karlsen, Saffron

    2013-02-01

    To investigate variations in explanations given for disparities in health care use between migrant and non-migrant groups, by clients and care providers in Sweden. Qualitative evidence collected during in-depth interviews with five 'migrant' health service clients and five physicians. The interview data generated three categories which were perceived by respondents to produce ethnic differences in health service use: "Communication issues", "Cultural differences in approaches to medical consultations" and "Effects of perceptions of inequalities in care quality and discrimination". Explanations for disparities in health care use in Sweden can be categorized into those reflecting social/structural conditions and the presence/absence of power and those using cultural/behavioural explanations. The negative perceptions of 'migrant' clients held by some Swedish physicians place the onus for addressing their poor health with the clients themselves and risks perpetuating their health disadvantage. The power disparity between doctors and 'migrant' patients encourages a sense of powerlessness and mistreatment among patients.

  5. Exploring the Effect of Embedded Scaffolding within Curricular Tasks on Third-Grade Students' Model-Based Explanations about Hydrologic Cycling

    Science.gov (United States)

    Zangori, Laura; Forbes, Cory T.; Schwarz, Christina V.

    2015-01-01

    Opportunities to generate model-based explanations are crucial for elementary students, yet are rarely foregrounded in elementary science learning environments despite evidence that early learners can reason from models when provided with scaffolding. We used a quasi-experimental research design to investigate the comparative impact of a scaffold…

  6. Why have socio-economic explanations between favoured over ...

    African Journals Online (AJOL)

    explanations trump cultural ones in the South African HIV aetiological literature? In this article, we explore how three factors (a belief in monogamy as a universal norm, HIV's emergence in a time of the construction of non-racialism, and a simplified understanding of HIV epidemiology) have intersected to produce this bias ...

  7. An Explanation of Economic Change and Development

    OpenAIRE

    Fusari, Angelo

    2014-01-01

    The contribution to the explanation of economic change that this paper sets out is centered on a core of interconnected endogenous variables, mainly innovation, radical uncertainty and entrepreneurship, which current economic analyses consider only in part and separately, sometimes as endogenous but for the most as exogenous. The article (and the formalized model) suppose that the functioning of the economy is not disturbed by the operation of pathological factors mainly concer...

  8. Superfluous neuroscience information makes explanations of psychological phenomena more appealing.

    Science.gov (United States)

    Fernandez-Duque, Diego; Evans, Jessica; Christian, Colton; Hodges, Sara D

    2015-05-01

    Does the presence of irrelevant neuroscience information make explanations of psychological phenomena more appealing? Do fMRI pictures further increase that allure? To help answer these questions, 385 college students in four experiments read brief descriptions of psychological phenomena, each one accompanied by an explanation of varying quality (good vs. circular) and followed by superfluous information of various types. Ancillary measures assessed participants' analytical thinking, beliefs on dualism and free will, and admiration for different sciences. In Experiment 1, superfluous neuroscience information increased the judged quality of the argument for both good and bad explanations, whereas accompanying fMRI pictures had no impact above and beyond the neuroscience text, suggesting a bias that is conceptual rather than pictorial. Superfluous neuroscience information was more alluring than social science information (Experiment 2) and more alluring than information from prestigious "hard sciences" (Experiments 3 and 4). Analytical thinking did not protect against the neuroscience bias, nor did a belief in dualism or free will. We conclude that the "allure of neuroscience" bias is conceptual, specific to neuroscience, and not easily accounted for by the prestige of the discipline. It may stem from the lay belief that the brain is the best explanans for mental phenomena.

  9. Arterial stiffening provides sufficient explanation for primary hypertension.

    Directory of Open Access Journals (Sweden)

    Klas H Pettersen

    2014-05-01

    Full Text Available Hypertension is one of the most common age-related chronic disorders, and by predisposing individuals for heart failure, stroke, and kidney disease, it is a major source of morbidity and mortality. Its etiology remains enigmatic despite intense research efforts over many decades. By use of empirically well-constrained computer models describing the coupled function of the baroreceptor reflex and mechanics of the circulatory system, we demonstrate quantitatively that arterial stiffening seems sufficient to explain age-related emergence of hypertension. Specifically, the empirically observed chronic changes in pulse pressure with age and the impaired capacity of hypertensive individuals to regulate short-term changes in blood pressure arise as emergent properties of the integrated system. The results are consistent with available experimental data from chemical and surgical manipulation of the cardio-vascular system. In contrast to widely held opinions, the results suggest that primary hypertension can be attributed to a mechanogenic etiology without challenging current conceptions of renal and sympathetic nervous system function.

  10. Assessing a novel polymer-wick based electrode for EEG neurophysiological research.

    Science.gov (United States)

    Pasion, Rita; Paiva, Tiago O; Pedrosa, Paulo; Gaspar, Hugo; Vasconcelos, Beatriz; Martins, Ana C; Amaral, Maria H; Nóbrega, João M; Páscoa, Ricardo; Fonseca, Carlos; Barbosa, Fernando

    2016-07-15

    The EEG technique has decades of valid applications in clinical and experimental neurophysiology. EEG equipment and data analysis methods have been characterized by remarkable developments, but the skin-to-electrode signal transfer remains a challenge for EEG recording. A novel quasi-dry system - the polymer wick-based electrode - was developed to overcome the limitations of conventional dry and wet silver/silver-chloride (Ag/AgCl) electrodes for EEG recording. Nine participants completed an auditory oddball protocol with simultaneous EEG acquisition using both the conventional Ag/AgCl and the wick electrodes. Wick system successfully recorded the expected P300 modulation. Standard ERP analysis, residual random noise analysis, and single-trial analysis of the P300 wave were performed in order to compare signal acquired by both electrodes. It was found that the novel wick electrode performed similarly to the conventional Ag/AgCl electrodes. The developed wick electrode appears to be a reliable alternative for EEG research, representing a promising halfway alternative between wet and dry electrodes. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Neurophysiology and new techniques to assess esophageal sensory function: an update.

    Science.gov (United States)

    Brock, Christina; McCallum, Richard W; Gyawali, C Prakash; Farmer, Adam D; Frøkjaer, Jens Brøndum; McMahon, Barry P; Drewes, Asbjørn Mohr

    2016-09-01

    This review aims to discuss the neurophysiology of the esophagus and new methods to assess esophageal nociception. Pain and other symptoms can be caused by diseases in the mucosa or muscular or sphincter dysfunction, together with abnormal pain processing, either in the peripheral or central nervous systems. Therefore, we present new techniques in the assessment of esophageal function and the potential role of the mucosal barrier in the generation and propagation of pain. We discuss the assessment and role of esophageal sphincters in nociception, as well as imaging and electrophysiological techniques, with examples of their use in understanding the sensory system following noxious stimuli to the esophagus. Additionally, we discuss the mechanisms behind functional diseases of the esophagus. We conclude that the new methods have identified many of the mechanisms behind malfunction of the mucosa, disturbances of muscular and sphincter functions, and the central response to different stimuli. Taken together, this has increased our understanding of esophageal disorders and may lead to new treatment modalities. © 2016 New York Academy of Sciences.

  12. Explanation and practice on ISO 9000

    International Nuclear Information System (INIS)

    Kwon, Dong Myeong

    2001-01-01

    This book reveals introduction on revision of ISO 9000:2000 with full account and contents of revision and change method change into ISO 9001:2000, the basic principle on ISO 9000:2000 and improvement and aim, definition on explanation, method for detail term, demand for ISO/KS A 9001:2000, quality management system development and transition way, standardization for quality management, manual of quality and making procedure and guide, case of quality manual and procedure and guide and ISO 9001:2000 / KS A 9001:2001 an English-Korean translation.

  13. [Intraoperative magnetic resonance imaging-guided functional neuronavigation plus intraoperative neurophysiological monitoring for microsurgical resection of lesions involving hand motor area].

    Science.gov (United States)

    Miao, Xing-lu; Chen, Zhi-juan; Yang, Wei-dong; Wang, Zeng-guang; Yu, Qing; Yue, Shu-yuan; Zhang, Jian-ning

    2013-01-15

    To explore the methods and applications of intraoperative magnetic resonance imaging (iMRI)-guided functional neuronavigation plus intraoperative neurophysiological monitoring (IONM) for microsurgical resection of lesions involving hand motor area. A total of 16 patients with brain lesions adjacent to hand motor area were recruited from January 2011 to April 2012. All of them underwent neuronavigator-assisted microsurgery. Also IONM was conducted to further map hand motor area and epileptogenic focus. High-field iMRI was employed to update the anatomical and functional imaging date and verify the extent of lesion resection. Brain shifting during the functional neuronavigation was corrected by iMRI in 5 patients. Finally, total lesion resection was achieved in 13 cases and subtotal resection in 3 cases. At Months 3-12 post-operation, hand motor function improved (n = 10) or remained unchanged (n = 6). None of them had persistent neurological deficit. The postoperative seizure improvement achieved Enge II level or above in 9 cases of brain lesions complicated with secondary epilepsy. Intraoperative MRI, functional neuronavigation and neurophysiological monitoring technique are complementary in microsurgery of brain lesions involving hand motor area. Combined use of these techniques can obtain precise location of lesions and hand motor functional structures and allow a maximum resection of lesion and minimization of postoperative neurological deficits.

  14. [Clinical, neurophysiological and psychological characteristics of neurosis in patients with panic disorders].

    Science.gov (United States)

    Tuter, N V

    2008-01-01

    Forty-eight patients with panic disorders (PD), aged 31,5 years, 17 men, 31 women, were studied. The results were analyzed in comparison to a control group which comprised 16 healthy people, 6 men, 10 women, mean age 29,5 years. A traditional clinical approach, including somatic, neurologic and psychiatric examination, was used in the study. Also, a neurophysiological study using compression and spectral analyses, EEG, cognitive evoked potentials, skin evoked potentials, was conducted. A psychological examination included assessment of personality traits (Cattell's test), MMPI personality profile, mechanisms of psychological defense, the "Life style index" and Sondy test. A decrease of - and -rhythms was found that implied the reduction of activation processes. The psychological data mirror as common signs characteristic of all PD, as well as psychological features characteristic of neurotic disorders. The results obtained confirm the heterogeneity of PD in nosological aspect that demands using differential approach to the problems of their diagnostics and treatment.

  15. Neurophysiological defects and neuronal gene deregulation in Drosophila mir-124 mutants.

    Directory of Open Access Journals (Sweden)

    Kailiang Sun

    2012-02-01

    Full Text Available miR-124 is conserved in sequence and neuronal expression across the animal kingdom and is predicted to have hundreds of mRNA targets. Diverse defects in neural development and function were reported from miR-124 antisense studies in vertebrates, but a nematode knockout of mir-124 surprisingly lacked detectable phenotypes. To provide genetic insight from Drosophila, we deleted its single mir-124 locus and found that it is dispensable for gross aspects of neural specification and differentiation. On the other hand, we detected a variety of mutant phenotypes that were rescuable by a mir-124 genomic transgene, including short lifespan, increased dendrite variation, impaired larval locomotion, and aberrant synaptic release at the NMJ. These phenotypes reflect extensive requirements of miR-124 even under optimal culture conditions. Comparison of the transcriptomes of cells from wild-type and mir-124 mutant animals, purified on the basis of mir-124 promoter activity, revealed broad upregulation of direct miR-124 targets. However, in contrast to the proposed mutual exclusion model for miR-124 function, its functional targets were relatively highly expressed in miR-124-expressing cells and were not enriched in genes annotated with epidermal expression. A notable aspect of the direct miR-124 network was coordinate targeting of five positive components in the retrograde BMP signaling pathway, whose activation in neurons increases synaptic release at the NMJ, similar to mir-124 mutants. Derepression of the direct miR-124 target network also had many secondary effects, including over-activity of other post-transcriptional repressors and a net incomplete transition from a neuroblast to a neuronal gene expression signature. Altogether, these studies demonstrate complex consequences of miR-124 loss on neural gene expression and neurophysiology.

  16. HIV in Japan: Epidemiologic puzzles and ethnographic explanations

    Directory of Open Access Journals (Sweden)

    Anthony S. DiStefano

    2016-12-01

    Full Text Available Japan is widely perceived to have a low level of HIV occurrence; however, its HIV epidemics also have been the subject of considerable misunderstanding globally. I used a ground truthing conceptual framework to meet two aims: first, to determine how accurately official surveillance data represented Japan's two largest epidemics (urban Kansai and Tokyo as understood and experienced on the ground; and second, to identify explanations for why the HIV epidemics were unfolding as officially reported. I used primarily ethnographic methods while drawing upon epidemiology, and compared government surveillance data to observations at community and institutional sites (459 pages of field notes; 175 persons observed, qualitative interviews with stakeholders in local HIV epidemics (n = 32, and document research (n = 116. This revealed seven epidemiologic puzzles involving officially reported trends and conspicuously missing information. Ethnographically grounded explanations are presented for each. These included factors driving the epidemics, which ranged from waning government and public attention to HIV, to gaps in sex education and disruptive leadership changes in public institutions approximately every two years. Factors constraining the epidemics also contributed to explanations. These ranged from subsidized medical treatment for most people living with HIV, to strong partnerships between government and a well-developed, non-governmental sector of HIV interventionists, and protective norms and built environments in the sex industry. Local and regional HIV epidemics were experienced and understood as worse than government reports indicated, and ground-level data often contradicted official knowledge. Results thus call into question epidemiologic trends, including recent stabilization of the national epidemic, and suggest the need for revisions to the surveillance system and strategies that address factors driving and constraining the epidemics. Based

  17. Opportunities for Inquiry Science in Montessori Classrooms: Learning from a Culture of Interest, Communication, and Explanation

    Science.gov (United States)

    Rinke, Carol R.; Gimbel, Steven J.; Haskell, Sophie

    2013-08-01

    Although classroom inquiry is the primary pedagogy of science education, it has often been difficult to implement within conventional classroom cultures. This study turned to the alternatively structured Montessori learning environment to better understand the ways in which it fosters the essential elements of classroom inquiry, as defined by prominent policy documents. Specifically, we examined the opportunities present in Montessori classrooms for students to develop an interest in the natural world, generate explanations in science, and communicate about science. Using ethnographic research methods in four Montessori classrooms at the primary and elementary levels, this research captured a range of scientific learning opportunities. The study found that the Montessori learning environment provided opportunities for students to develop enduring interests in scientific topics and communicate about science in various ways. The data also indicated that explanation was largely teacher-driven in the Montessori classroom culture. This study offers lessons for both conventional and Montessori classrooms and suggests further research that bridges educational contexts.

  18. The Difficulties of Reductionistic Explanation of Moral Knowledge

    Directory of Open Access Journals (Sweden)

    SeyyedAli Asghari

    2016-03-01

    Full Text Available Moral reductionist believes that the reality of moral qualities are the same qualities which can be expressed with immoral words. Such an ontological view has an epistemological aspect which states our understanding of moral facts is either our understanding of immoral facts or our deductions of immoral understanding. From moral reductionists and especially the naturalists’ point of view, the ability to explain moral knowledge without resorting to some theories such as moral intuition is considered to be an important advantage and even a strong reason for their view. Therefore, the present paper is going to study the reductionistic explanations about moral knowledge and justifications of moral believes. We have come to the conclusion that among the explanations presented by the naturalists, analytic knowledge has the same problems which have discredited the theory of analytic reductionism. Also, deducing value from non-value is either facing the logical gap of is-must; or if there is a meaningful descriptive-valuable link, we can’t finally come to unconditional moral results.

  19. ExplaNet: A Collaborative Learning Tool and Hybrid Recommender System for Student-Authored Explanations

    Science.gov (United States)

    Masters, Jessica; Madhyastha, Tara; Shakouri, Ali

    2008-01-01

    ExplaNet is a web-based, anonymous, asynchronous explanation-sharing network. Instructors post questions to the network and students submit explanatory answers. Students then view and rank the explanations submitted by their peers before optionally resubmitting a final and revised answer. Three classroom evaluations of ExplaNet showed that by…

  20. Evolutionary explanations in medical and health profession courses: are you answering your students' "why" questions?

    Directory of Open Access Journals (Sweden)

    Malyango Avelin A

    2005-05-01

    Full Text Available Abstract Background Medical and pre-professional health students ask questions about human health that can be answered in two ways, by giving proximate and evolutionary explanations. Proximate explanations, most common in textbooks and classes, describe the immediate scientifically known biological mechanisms of anatomical characteristics or physiological processes. These explanations are necessary but insufficient. They can be complemented with evolutionary explanations that describe the evolutionary processes and principles that have resulted in human biology we study today. The main goal of the science of Darwinian Medicine is to investigate human disease, disorders, and medical complications from an evolutionary perspective. Discussion This paper contrasts the differences between these two types of explanations by describing principles of natural selection that underlie medical questions. Thus, why is human birth complicated? Why does sickle cell anemia exist? Why do we show symptoms like fever, diarrhea, and coughing when we have infection? Why do we suffer from ubiquitous age-related diseases like arteriosclerosis, Alzheimer's and others? Why are chronic diseases like type II diabetes and obesity so prevalent in modern society? Why hasn't natural selection eliminated the genes that cause common genetic diseases like hemochromatosis, cystic fibrosis, Tay sachs, PKU and others? Summary In giving students evolutionary explanations professors should underscore principles of natural selection, since these can be generalized for the analysis of many medical questions. From a research perspective, natural selection seems central to leading hypotheses of obesity and type II diabetes and might very well explain the occurrence of certain common genetic diseases like cystic fibrosis, hemochromatosis, Tay sachs, Fragile X syndrome, G6PD and others because of their compensating advantages. Furthermore, armed with evolutionary explanations, health care

  1. Neuronal oscillations enhance stimulus discrimination by ensuring action potential precision

    DEFF Research Database (Denmark)

    Schaefer, Andreas T; Angelo, Kamilla; Spors, Hartwig

    2006-01-01

    generated membrane potential oscillations dramatically improve action potential (AP) precision by removing the membrane potential variance associated with jitter-accumulating trains of APs. This increased AP precision occurred irrespective of cell type and--at oscillation frequencies ranging from 3 to 65 Hz......Although oscillations in membrane potential are a prominent feature of sensory, motor, and cognitive function, their precise role in signal processing remains elusive. Here we show, using a combination of in vivo, in vitro, and theoretical approaches, that both synaptically and intrinsically......, membrane potential oscillations dramatically enhance the discriminatory capabilities of individual neurons and networks of cells and provide one attractive explanation for their abundance in neurophysiological systems....

  2. Cough: neurophysiology, methods of research, pharmacological therapy and phonoaudiology

    Directory of Open Access Journals (Sweden)

    Balbani, Aracy Pereira Silveira

    2012-01-01

    Full Text Available Introduction: The cough is the more common respiratory symptom in children and adults. Objective: To present a revision on the neurophysiology and the methods for study of the consequence of the cough, as well as the pharmacotherapy and phonoaudiology therapy of the cough, based on the works published between 2005 and 2010 and indexed in the bases Medline, Lilacs and Library Cochrane under them to keywords "cough" or "anti-cough". Synthesis of the data: The consequence of the cough involves activation of receiving multiples becomes vacant in the aerial ways and of neural projections of the nucleus of the solitary treatment for other structures of the central nervous system. Experimental techniques allow studying the consequence of the cough to the cellular and molecular level to develop new anti-cough agents. It does not have evidences of that anti-cough exempt of medical lapsing they have superior effectiveness to the one of placebo for the relief of the cough. The phonoaudiology therapy can benefit patients with refractory chronic cough to the pharmacological treatment, over all when paradoxical movement of the vocal folds coexists. Final Comments: The boarding to multidiscipline has basic paper in the etiological diagnosis and treatment of the cough. The otolaryngologist must inform the patients on the risks of the anti-cough of free sales in order to prevent adverse poisonings and effect, especially in children.

  3. Social selection is a powerful explanation for prosociality.

    Science.gov (United States)

    Nesse, Randolph M

    2016-01-01

    Cultural group selection helps explain human cooperation, but social selection offers a complementary, more powerful explanation. Just as sexual selection shapes extreme traits that increase matings, social selection shapes extreme traits that make individuals preferred social partners. Self-interested partner choices create strong and possibly runaway selection for prosocial traits, without requiring group selection, kin selection, or reciprocity.

  4. Dynamical 3-Space: Alternative Explanation of the "Dark Matter Ring"

    Directory of Open Access Journals (Sweden)

    Cahill R. T.

    2007-10-01

    Full Text Available NASA has claimed the discovery of a “Ring of Dark Matter” in the galaxy cluster CL 0024 +17, see Jee M.J. et al. arXiv:0705.2171, based upon gravitational lensing data. Here we show that the lensing can be given an alternative explanation that does not involve “dark matter”. This explanation comes from the new dynamics of 3-space. This dynamics involves two constant G and alpha — the fine structure constant. This dynamics has explained the bore hole anomaly, spiral galaxy flat rotation speeds, the masses of black holes in spherical galaxies, gravitational light bending and lensing, all without invoking “dark matter”, and also the supernova redshift data without the need for “dark energy”.

  5. An Explanation of the Missing Flux from Boyajian's Mysterious Star

    Energy Technology Data Exchange (ETDEWEB)

    Foukal, Peter [192 Willow Road, Nahant, MA 01908 (United States)

    2017-06-10

    A previously unremarkable star in the constellation Cygnus has, in the past year, become known as the most mysterious object in our Galaxy. Boyajian’s star exhibits puzzling episodes of sporadic, deep dimming discovered in photometry with the Kepler Mission. Proposed explanations have focused on its obscuration by colliding exoplanets, exocomets, and even intervention of alien intelligence. These hypotheses have considered only phenomena external to the star because the radiative flux missing in the dimmings was believed to exceed the star’s storage capacity. We point out that modeling of variations in solar luminosity indicates that convective stars can store the required fluxes. It also suggests explanations for (a) a reported time-profile asymmetry of the short, deep dimmings and (b) a slower, decadal scale dimming reported from archival and Kepler photometry. Our findings suggest a broader range of explanations of Boyajian’s star that may produce new insights into stellar magneto-convection.

  6. Interpreting Black-Box Classifiers Using Instance-Level Visual Explanations

    Energy Technology Data Exchange (ETDEWEB)

    Tamagnini, Paolo; Krause, Josua W.; Dasgupta, Aritra; Bertini, Enrico

    2017-05-14

    To realize the full potential of machine learning in diverse real- world domains, it is necessary for model predictions to be readily interpretable and actionable for the human in the loop. Analysts, who are the users but not the developers of machine learning models, often do not trust a model because of the lack of transparency in associating predictions with the underlying data space. To address this problem, we propose Rivelo, a visual analytic interface that enables analysts to understand the causes behind predictions of binary classifiers by interactively exploring a set of instance-level explanations. These explanations are model-agnostic, treating a model as a black box, and they help analysts in interactively probing the high-dimensional binary data space for detecting features relevant to predictions. We demonstrate the utility of the interface with a case study analyzing a random forest model on the sentiment of Yelp reviews about doctors.

  7. Synergy and Students' Explanations: Exploring the Role of Generic and Content-Specific Scaffolds

    Science.gov (United States)

    Delen, Ibrahim; Krajcik, Joseph

    2018-01-01

    In this study, we explored how a teacher used a new mobile application that enables students to collect data inside and outside the classroom, and then use the data to create scientific explanations by using claim-evidence-reasoning framework. Previous technologies designed to support scientific explanations focused on how these programs improve…

  8. Indirect assessment of an interpretation bias in humans: Neurophysiological and behavioral correlates

    Directory of Open Access Journals (Sweden)

    Anita eSchick

    2013-06-01

    Full Text Available Affective state can influence cognition leading to biased information processing, interpretation, attention, and memory. Such bias has been reported to be essential for the onset and maintenance of different psychopathologies, particularly affective disorders. However, empirical evidence has been very heterogeneous and little is known about the neurophysiological mechanisms underlying cognitive bias and its time-course. We therefore investigated the interpretation of ambiguous stimuli as indicators of biased information processing with an ambiguous cue-conditioning paradigm. In an acquisition phase, participants learned to discriminate two tones of different frequency, which acquired emotional and motivational value due to subsequent feedback (monetary gain or avoidance of monetary loss. In the test phase, three additional tones of intermediate frequencies were presented, whose interpretation as positive (approach of reward or negative (avoidance of punishment, indicated by a button press, was used as an indicator of the bias. Twenty healthy volunteers participated in this paradigm while a 64-channel electroencephalogram was recorded. Participants also completed questionnaires assessing individual differences in depression and rumination. Overall, we found a small positive bias, which correlated negatively with reflective pondering, a type of rumination. As expected, reaction times were increased for intermediate tones. ERP amplitudes between 300 – 700 ms post-stimulus differed depending on the interpretation of the intermediate tones. A negative compared to a positive interpretation led to an amplitude increase over frontal electrodes. Our study provides evidence that in humans, as in animal research, the ambiguous cue-conditioning paradigm is a valid procedure for indirectly assessing ambiguous cue interpretation and a potential interpretation bias, which is sensitive to individual differences in affect-related traits.

  9. The individual tolerance concept is not the sole explanation for the probit dose-effect model

    Energy Technology Data Exchange (ETDEWEB)

    Newman, M.C.; McCloskey, J.T.

    2000-02-01

    Predominant methods for analyzing dose- or concentration-effect data (i.e., probit analysis) are based on the concept of individual tolerance or individual effective dose (IED, the smallest characteristic dose needed to kill an individual). An alternative explanation (stochasticity hypothesis) is that individuals do not have unique tolerances: death results from stochastic processes occurring similarly in all individuals. These opposing hypotheses were tested with two types of experiments. First, time to stupefaction (TTS) was measured for zebra fish (Brachydanio rerio) exposed to benzocaine. The same 40 fish were exposed during five trials to test if the same order for TTS was maintained among trials. The IED hypothesis was supported with a minor stochastic component being present. Second, eastern mosquitofish (Gambusia holbrooki) were exposed to sublethal or lethal NaCl concentrations until a large portion of the lethally exposed fish died. After sufficient time for recovery, fish sublethally exposed and fish surviving lethal exposure were exposed simultaneously to lethal NaCl concentrations. No statistically significant effect was found of previous exposure on survival time but a large stochastic component to the survival dynamics was obvious. Repetition of this second type of test with pentachlorophenol also provided no support for the IED hypothesis. The authors conclude that neither hypothesis alone was the sole or dominant explanation for the lognormal (probit) model. Determination of the correct explanation (IED or stochastic) or the relative contributions of each is crucial to predicting consequences to populations after repeated or chronic exposures to any particular toxicant.

  10. Asymmetric activation of the anterior cerebral cortex in recipients of IRECA: Preliminary evidence for the energetic effects of an intention-based biofield treatment modality on human neurophysiology

    NARCIS (Netherlands)

    Pike, C.; Vernon, D.; Hald, L.A.

    2014-01-01

    Neurophysiologic studies of mindfulness link the health benefits of meditation to activation of the left-anterior cerebral cortex. The similarity and functional importance of intention and attentional stance in meditative and biofield therapeutic practices suggest that modulation of recipient

  11. Sixth Graders' Co-Construction of Explanations of a Disturbance in an Ecosystem: Exploring Relationships between Grouping, Reflective Scaffolding, and Evidence-Based Explanations

    Science.gov (United States)

    Kyza, Eleni A.; Constantinou, Costas P.; Spanoudis, George

    2011-01-01

    We report on a study investigating the relationship between cognitive ability grouping, reflective inquiry scaffolding, and students' collaborative explanations of an ecosystem disturbance which took place when a number of flamingo birds died in a salt lake because of nearby intensive human activities. Twenty-six pairs of students from two intact…

  12. Crystal Structure, Conformational Analysis, and Charge Density Distribution for Eng-Epifisetinidol: An Explanation for Regiospecific Aromatic Substitution of 5-Deoxyflavan

    Science.gov (United States)

    Fred L. Tobiason; Frank R. Fronczek; Jan P. Steynberg; Elizabeth C. Steynberg; Richard W. Hemingway; Wayne L. Mattice

    1993-01-01

    Molecular modeling and molecular orbital analyses of ent-epifisetinidol gave &ood predictions of the approximate "reverse half-chair" conformation found for the crystal structure. MNDO and AM1 analyses of HOMO electron densities provided an explanation for the stereospecific electrophilic aromatic substitution at C(6) in 5-deoxy-flavans...

  13. HIV-positive females show blunted neurophysiological responses in an emotion-attention dual task paradigm.

    Science.gov (United States)

    Tartar, Jaime L; McIntosh, Roger C; Rosselli, Monica; Widmayer, Susan M; Nash, Allan J

    2014-06-01

    Although HIV is associated with decreased emotional and cognitive functioning, the mechanisms through which affective changes can alter cognitive processes in HIV-infected individuals are unknown. We aimed to clarify this question through testing the extent to which emotionally negative stimuli prime attention to a subsequent infrequently occurring auditory tone in HIV+ compared to HIV- females. Attention to emotional compared to non-emotional pictures was measured via the LPP ERP. Subsequent attention was indexed through the N1 and late processing negativity ERP. We also assessed mood and cognitive functioning in both groups. In HIV- females, emotionally negative pictures, compared to neutral pictures, resulted in an enhanced LPP to the pictures and an enhanced N1 to subsequent tones. The HIV+ group did not show a difference in the LPP measure between picture categories, and accordingly, did not show a priming effect to the subsequent infrequent tones. The ERP findings, combined with neuropsychological deficits, suggest that HIV+ females show impairments in attention to emotionally-laden stimuli and that this impairment might be related to a loss of affective priming. This study is the first to provide physiological evidence that the LPP, a measure of attention to emotionally-charged visual stimuli, is reduced in HIV-infected individuals. These results set the stage for future work aimed at localizing brain activation to emotional stimuli in HIV+ individuals. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  14. The Virtual Threat Effect: A Test of Competing Explanations for the Effects of Racial Stereotyping in Video Games on Players' Cognitions.

    Science.gov (United States)

    Behm-Morawitz, Elizabeth; Hoffswell, Joseph; Chen, Szu-Wei

    2016-05-01

    Past research provides evidence that embodying a racially stereotyped African American video game character triggers stereotyped thinking among White players. However, the mechanisms through which virtual racial embodiment of a negatively stereotyped character in a video game impacts stereotyped thinking are still unknown. This study expands on past research and utilizes a between-subjects experimental design to test two possible theoretical explanations: the virtual threat effect and presence. On the one hand, embodying a negatively stereotyped African American character may elicit stereotyped thinking among White players due to the mere exposure to the threatening stereotype. According to this explanation, negative affective response to the threatening stimulus predicts stereotyping. On the other hand, the process of embodying, not just observing, the stereotyped African American character suggests that presence in the game may determine how impactful the game imagery is on White players' stereotyping of African Americans. In this case, level of presence would predict stereotyping. The findings of this study advance research by providing evidence of a psychological explanation for the negative effects of embodying a racially stereotyped video game character on players' race-related perceptions. We conceptualize the "virtual threat effect," which may be applied in additional contexts to understand how embodying stereotyped representations of outgroups in virtual environments may negatively affect individuals' perceptions and support of these groups.

  15. What was historical about natural history? Contingency and explanation in the science of living things.

    Science.gov (United States)

    Harrison, Peter

    2016-08-01

    There is a long-standing distinction in Western thought between scientific and historical modes of explanation. According to Aristotle's influential account of scientific knowledge there cannot be an explanatory science of what is contingent and accidental, such things being the purview of a descriptive history. This distinction between scientia and historia continued to inform assumptions about scientific explanation into the nineteenth century and is particularly significant when considering the emergence of biology and its displacement of the more traditional discipline of natural history. One of the consequences of this nineteenth-century transition was that while modern evolutionary theory retained significant, if often implicit, historical components, these were often overlooked as evolutionary biology sought to accommodate itself to a model of scientific explanation that involved appeals to laws of nature. These scientific aspirations of evolutionary biology sometimes sit uncomfortably with its historical dimension. This tension lies beneath recent philosophical critiques of evolutionary theory and its modes of explanation. Such critiques, however, overlook the fact that there are legitimate modes of historical explanation that do not require recourse to laws of nature. But responding to these criticisms calls for a more explicit recognition of the affinities between evolutionary biology and history. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  16. The Attentional Blink Provides Episodic Distinctiveness : Sparing at a Cost

    NARCIS (Netherlands)

    Wyble, Brad; Bowman, Howard; Nieuwenstein, Mark

    The attentional blink (J. E. Raymond. K. L. Shapiro, & K. M. Arnett. 1992) refers to an apparent gap in perception observed when a second target follows a first within several hundred milliseconds. Theoretical and computational work have provided explanations for early sets of blink data, but more

  17. Information performances and illative sequences: Sequential organization of explanations of chemical phase equilibrium

    Science.gov (United States)

    Brown, Nathaniel James Swanton

    While there is consensus that conceptual change is surprisingly difficult, many competing theories of conceptual change co-exist in the literature. This dissertation argues that this discord is partly the result of an inadequate account of the unwritten rules of human social interaction that underlie the field's preferred methodology---semi-structured interviewing. To better understand the contributions of interaction during explanations, I analyze eight undergraduate general chemistry students as they attempt to explain to various people, for various reasons, why phenomena involving chemical phase equilibrium occur. Using the methods of interaction analysis, I characterize the unwritten, but systematic, rules that these participants follow as they explain. The result is a description of the contributions of interaction to explaining. Each step in each explanation is a jointly performed expression of a subject-predicate relation, an interactive accomplishment I call an information performance (in-form, for short). Unlike clauses, in-forms need not have a coherent grammatical structure. Unlike speaker turns, in-forms have the clear function of expressing information. Unlike both clauses and speaker turns, in-forms are a co-construction, jointly performed by both the primary speaker and the other interlocutor. The other interlocutor strongly affects the form and content of each explanation by giving or withholding feedback at the end of each in-form, moments I call feedback-relevant places. While in-forms are the bricks out of which the explanation is constructed, they are secured by a series of inferential links I call an illative sequence. Illative sequences are forward-searching, starting with a remembered fact or observation and following a chain of inferences in the hope it leads to the target phenomenon. The participants treat an explanation as a success if the illative sequence generates an in-form that describes the phenomenon. If the illative sequence does

  18. Arousal vs. Relaxation: A Comparison of the Neurophysiological and Cognitive Correlates of Vajrayana and Theravada Meditative Practices

    Science.gov (United States)

    Amihai, Ido; Kozhevnikov, Maria

    2014-01-01

    Based on evidence of parasympathetic activation, early studies defined meditation as a relaxation response. Later research attempted to categorize meditation as either involving focused or distributed attentional systems. Neither of these hypotheses received strong empirical support, and most of the studies investigated Theravada style meditative practices. In this study, we compared neurophysiological (EEG, EKG) and cognitive correlates of meditative practices that are thought to utilize either focused or distributed attention, from both Theravada and Vajrayana traditions. The results of Study 1 show that both focused (Shamatha) and distributed (Vipassana) attention meditations of the Theravada tradition produced enhanced parasympathetic activation indicative of a relaxation response. In contrast, both focused (Deity) and distributed (Rig-pa) meditations of the Vajrayana tradition produced sympathetic activation, indicative of arousal. Additionally, the results of Study 2 demonstrated an immediate dramatic increase in performance on cognitive tasks following only Vajrayana styles of meditation, indicating enhanced phasic alertness due to arousal. Furthermore, our EEG results showed qualitatively different patterns of activation between Theravada and Vajrayana meditations, albeit highly similar activity between meditations within the same tradition. In conclusion, consistent with Tibetan scriptures that described Shamatha and Vipassana techniques as those that calm and relax the mind, and Vajrayana techniques as those that require ‘an awake quality’ of the mind, we show that Theravada and Vajrayana meditations are based on different neurophysiological mechanisms, which give rise to either a relaxation or arousal response. Hence, it may be more appropriate to categorize meditations in terms of relaxation vs. arousal, whereas classification methods that rely on the focused vs. distributed attention dichotomy may need to be reexamined. PMID:25051268

  19. Arousal vs. relaxation: a comparison of the neurophysiological and cognitive correlates of Vajrayana and Theravada meditative practices.

    Directory of Open Access Journals (Sweden)

    Ido Amihai

    Full Text Available Based on evidence of parasympathetic activation, early studies defined meditation as a relaxation response. Later research attempted to categorize meditation as either involving focused or distributed attentional systems. Neither of these hypotheses received strong empirical support, and most of the studies investigated Theravada style meditative practices. In this study, we compared neurophysiological (EEG, EKG and cognitive correlates of meditative practices that are thought to utilize either focused or distributed attention, from both Theravada and Vajrayana traditions. The results of Study 1 show that both focused (Shamatha and distributed (Vipassana attention meditations of the Theravada tradition produced enhanced parasympathetic activation indicative of a relaxation response. In contrast, both focused (Deity and distributed (Rig-pa meditations of the Vajrayana tradition produced sympathetic activation, indicative of arousal. Additionally, the results of Study 2 demonstrated an immediate dramatic increase in performance on cognitive tasks following only Vajrayana styles of meditation, indicating enhanced phasic alertness due to arousal. Furthermore, our EEG results showed qualitatively different patterns of activation between Theravada and Vajrayana meditations, albeit highly similar activity between meditations within the same tradition. In conclusion, consistent with Tibetan scriptures that described Shamatha and Vipassana techniques as those that calm and relax the mind, and Vajrayana techniques as those that require 'an awake quality' of the mind, we show that Theravada and Vajrayana meditations are based on different neurophysiological mechanisms, which give rise to either a relaxation or arousal response. Hence, it may be more appropriate to categorize meditations in terms of relaxation vs. arousal, whereas classification methods that rely on the focused vs. distributed attention dichotomy may need to be reexamined.

  20. Developing Explanations and Developing Understanding: Students Explain the Phases of the Moon Using Visual Representations

    Science.gov (United States)

    Parnafes, Orit

    2012-01-01

    This article presents a theoretical model of the process by which students construct and elaborate explanations of scientific phenomena using visual representations. The model describes progress in the underlying conceptual processes in students' explanations as a reorganization of fine-grained knowledge elements based on the Knowledge in Pieces…

  1. Developmental Origins of Biological Explanations: The case of infants' internal property bias.

    Science.gov (United States)

    Taborda-Osorio, Hernando; Cheries, Erik W

    2017-10-01

    People's explanations about the biological world are heavily biased toward internal, non-obvious properties. Adults and children as young as 5 years of age find internal properties more causally central than external features for explaining general biological processes and category membership. In this paper, we describe how this 'internal property bias' may be grounded in two different developmental precursors observed in studies with infants: (1) an early understanding of biological agency that is apparent in infants' reasoning about animals, and (2) the acquisition of kind-based representations that distinguish between essential and accidental properties, spanning from animals to artifacts. We argue that these precursors may support the progressive construction of the notion of biological kinds and explanations during childhood. Shortly after their first year of life, infants seem to represent the internal properties of animates as more central and identity-determining that external properties. Over time, this skeletal notion of biological kinds is integrated into diverse explanations about kind membership and biological processes, with an increasingly better understanding of the causal role of internal properties.

  2. Box-and-arrow explanations need not be more abstract than neuroscientific mechanism descriptions.

    Science.gov (United States)

    Datteri, Edoardo; Laudisa, Federico

    2014-01-01

    The nature of the relationship between box-and-arrow (BA) explanations and neuroscientific mechanism descriptions (NMDs) is a key foundational issue for cognitive science. In this article we attempt to identify the nature of the constraints imposed by BA explanations on the formulation of NMDs. On the basis of a case study about motor control, we argue that BA explanations and NMDs both identify regularities that hold in the system, and that these regularities place constraints on the formulation of NMDs from BA analyses, and vice versa. The regularities identified in the two kinds of explanation play a crucial role in reasoning about the relationship between them, and in justifying the use of neuroscientific experimental techniques for the empirical testing of BA analyses of behavior. In addition, we make claims concerning the similarities and differences between BA analyses and NMDs. First, we argue that both types of explanation describe mechanisms. Second, we propose that they differ in terms of the theoretical vocabulary used to denote the entities and properties involved in the mechanism and engaging in regular, mutual interactions. On the contrary, the notion of abstractness, defined as omission of detail, does not help to distinguish BA analyses from NMDs: there is a sense in which BA analyses are more detailed than NMDs. In relation to this, we also focus on the nature of the extra detail included in NMDs and missing from BA analyses, arguing that such detail does not always concern how the system works. Finally, we propose reasons for doubting that BA analyses, unlike NMDs, may be considered "mechanism sketches." We have developed these views by critically analyzing recent claims in the philosophical literature regarding the foundations of cognitive science.

  3. Box-and-arrow explanations need not be more abstract than neuroscientific mechanism descriptions

    Directory of Open Access Journals (Sweden)

    Edoardo eDatteri

    2014-05-01

    Full Text Available The nature of the relationship between box-and-arrow (BA explanations and neuroscientific mechanism descriptions (NMDs is a key foundational issue for cognitive science. In this article we attempt to identify the nature of the constraints imposed by BA explanations on the formulation of NMDs. On the basis of a case study about motor control, we argue that BA explanations and NMDs both identify regularities that hold in the system, and that these regularities place constraints on the formulation of NMDs from BA analyses, and vice versa. The regularities identified in the two kinds of explanation play a crucial role in reasoning about the relationship between them, and in justifying the use of neuroscientific experimental techniques for the empirical testing of BA analyses of behavior. In addition, we make claims concerning the similarities and differences between BA analyses and NMDs. First, we argue that both types of explanation describe mechanisms. Second, we propose that they differ in terms of the theoretical vocabulary used to denote the entities and properties involved in the mechanism and engaging in regular, mutual interactions. On the contrary, the notion of abstractness, defined as omission of detail, does not help to distinguish BA analyses from NMDs: there is a sense in which BA analyses are more detailed than NMDs. In relation to this, we also focus on the nature of the extra detail included in NMDs and missing from BA analyses, arguing that such detail does not always concern how the system works. Finally, we propose reasons for doubting that BA analyses, unlike NMDs, may be considered mechanism sketches. We have developed these views by critically analyzing recent claims in the philosophical literature regarding the foundations of cognitive science.

  4. Neurophysiological analytics for all! Free open-source software tools for documenting, analyzing, visualizing, and sharing using electronic notebooks.

    Science.gov (United States)

    Rosenberg, David M; Horn, Charles C

    2016-08-01

    Neurophysiology requires an extensive workflow of information analysis routines, which often includes incompatible proprietary software, introducing limitations based on financial costs, transfer of data between platforms, and the ability to share. An ecosystem of free open-source software exists to fill these gaps, including thousands of analysis and plotting packages written in Python and R, which can be implemented in a sharable and reproducible format, such as the Jupyter electronic notebook. This tool chain can largely replace current routines by importing data, producing analyses, and generating publication-quality graphics. An electronic notebook like Jupyter allows these analyses, along with documentation of procedures, to display locally or remotely in an internet browser, which can be saved as an HTML, PDF, or other file format for sharing with team members and the scientific community. The present report illustrates these methods using data from electrophysiological recordings of the musk shrew vagus-a model system to investigate gut-brain communication, for example, in cancer chemotherapy-induced emesis. We show methods for spike sorting (including statistical validation), spike train analysis, and analysis of compound action potentials in notebooks. Raw data and code are available from notebooks in data supplements or from an executable online version, which replicates all analyses without installing software-an implementation of reproducible research. This demonstrates the promise of combining disparate analyses into one platform, along with the ease of sharing this work. In an age of diverse, high-throughput computational workflows, this methodology can increase efficiency, transparency, and the collaborative potential of neurophysiological research. Copyright © 2016 the American Physiological Society.

  5. Education's impact on explanations of radical right-wing voting

    NARCIS (Netherlands)

    Lubbers, M.; Tolsma, J.

    2011-01-01

    One of the reactions to the large demographic changes in Europe due to migration has been the rise of radical right-wing parties. Previous research has shown that education is one of the most relevant explanations of this voting behaviour. By pooling the European Social Surveys from 2002, 2004, 2006

  6. Pluralism, Pragmatism and Functional Explanations

    Directory of Open Access Journals (Sweden)

    Shaw Jamie

    2016-04-01

    Full Text Available While many philosophers speak of ‘pluralism’ within philosophy of biology, there has been little said about what such pluralism amounts to or what its underlying assumptions are. This has provoked so me anxiety about whether pluralism is compatible with their commitment to naturalism (Cussins 1992. This paper surveys three prominent pluralist positions (Sandra Mitchell and Michael Dietrich’s (2006 ‘integrative pluralism’, and both Peter Godfrey-Smith’s (1993 and Beth Preston’s (1998 pluralist analyses of functional explanations in evolutionary biology and demonstrates how all three are committed to a form of pragmatism. This analysis both clarifies the justification and grounding of pluralism and allows these pluralisms to avoid the criticisms of Cussins. I close by making some more general points about pluralism and its relationship to history and integration.

  7. Normative study of theme identifiability: Instructions with and without explanation of the false memory effect.

    Science.gov (United States)

    Beato, Maria Soledad; Cadavid, Sara

    2016-12-01

    False-memory illusions have been widely studied using the Deese/Roediger-McDermott paradigm (DRM). In this paradigm, words semantically related to a single nonpresented critical word are studied. In a later memory test, critical words are often falsely recalled and recognized. The present normative study was conducted to measure the theme identifiability of 60 associative word lists in Spanish that include six words (e.g., stove, coat, blanket, scarf, chill, and bonnet) that are simultaneously associated with three critical words (e.g., HEAT, COLD, and WINTER; Beato & Díez, Psicothema, 26, 457-463, 2011). Different levels of backward associative strength were used in the construction of the DRM lists. In addition, we used two types of instructions to obtain theme identifiability. In the without-explanation condition, traditional instructions were used, requesting participants to write the theme list. In the with-explanation condition, the false-memory effect and how the lists were built were explained, and an example of a DRM list and critical words was shown. Participants then had to discover the critical words. The results showed that all lists produced theme identifiability. Moreover, some lists had a higher theme identifiability rate (e.g., 61 % for the critical words LOVE, BOYFRIEND, COUPLE) than others (e.g., 24 % for CITY, PLACE, VILLAGE). After comparing the theme identifiabilities in the different conditions, the results indicated higher theme identifiability when the false-memory effect was explained than without such an explanation. Overall, these new normative data provide a useful tool for those experiments that, for example, aim to analyze the wide differences observed in false memory with DRM lists and the role of theme identifiability.

  8. Neurophysiology underlying influence of stimulus reliability on audiovisual integration.

    Science.gov (United States)

    Shatzer, Hannah; Shen, Stanley; Kerlin, Jess R; Pitt, Mark A; Shahin, Antoine J

    2018-01-24

    We tested the predictions of the dynamic reweighting model (DRM) of audiovisual (AV) speech integration, which posits that spectrotemporally reliable (informative) AV speech stimuli induce a reweighting of processing from low-level to high-level auditory networks. This reweighting decreases sensitivity to acoustic onsets and in turn increases tolerance to AV onset asynchronies (AVOA). EEG was recorded while subjects watched videos of a speaker uttering trisyllabic nonwords that varied in spectrotemporal reliability and asynchrony of the visual and auditory inputs. Subjects judged the stimuli as in-sync or out-of-sync. Results showed that subjects exhibited greater AVOA tolerance for non-blurred than blurred visual speech and for less than more degraded acoustic speech. Increased AVOA tolerance was reflected in reduced amplitude of the P1-P2 auditory evoked potentials, a neurophysiological indication of reduced sensitivity to acoustic onsets and successful AV integration. There was also sustained visual alpha band (8-14 Hz) suppression (desynchronization) following acoustic speech onsets for non-blurred vs. blurred visual speech, consistent with continuous engagement of the visual system as the speech unfolds. The current findings suggest that increased spectrotemporal reliability of acoustic and visual speech promotes robust AV integration, partly by suppressing sensitivity to acoustic onsets, in support of the DRM's reweighting mechanism. Increased visual signal reliability also sustains the engagement of the visual system with the auditory system to maintain alignment of information across modalities. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  9. Bilirubin-Induced Neurological Dysfunction: A Clinico-Radiological-Neurophysiological Correlation in 30 Consecutive Children.

    Science.gov (United States)

    van Toorn, Ronald; Brink, Philip; Smith, Johan; Ackermann, Christelle; Solomons, Regan

    2016-12-01

    The clinical expression of bilirubin-induced neurological dysfunction varies according to severity and location of the disease. Definitions have been proposed to describe different bilirubin-induced neurological dysfunction subtypes. Our objective was to describe the severity and clinico-radiological-neurophysiological correlation in 30 consecutive children with bilirubin-induced neurological dysfunction seen over a period of 5 years. Thirty children exposed to acute neonatal bilirubin encephalopathy were included in the study. The mean peak total serum bilirubin level was 625 μmol/L (range 480-900 μmol/L). Acoustic brainstem responses were abnormal in 73% (n = 22). Pallidal hyperintensity was observed on magnetic resonance imaging in 20 children. Peak total serum bilirubin levels correlated with motor severity (P = .03). Children with severe motor impairment were likely to manifest severe auditory neuropathy (P bilirubin-induced neurological dysfunction subtype, and the majority of children had abnormal acoustic brainstem responses and magnetic resonance imaging. © The Author(s) 2016.

  10. A Pause-then-Cancel model of stopping: evidence from basal ganglia neurophysiology.

    Science.gov (United States)

    Schmidt, Robert; Berke, Joshua D

    2017-04-19

    Many studies have implicated the basal ganglia in the suppression of action impulses ('stopping'). Here, we discuss recent neurophysiological evidence that distinct hypothesized processes involved in action preparation and cancellation can be mapped onto distinct basal ganglia cell types and pathways. We examine how movement-related activity in the striatum is related to a 'Go' process and how going may be modulated by brief epochs of beta oscillations. We then describe how, rather than a unitary 'Stop' process, there appear to be separate, complementary 'Pause' and 'Cancel' mechanisms. We discuss the implications of these stopping subprocesses for the interpretation of the stop-signal reaction time-in particular, some activity that seems too slow to causally contribute to stopping when assuming a single Stop processes may actually be fast enough under a Pause-then-Cancel model. Finally, we suggest that combining complementary neural mechanisms that emphasize speed or accuracy respectively may serve more generally to optimize speed-accuracy trade-offs.This article is part of the themed issue 'Movement suppression: brain mechanisms for stopping and stillness'. © 2017 The Author(s).

  11. Drawing on student knowledge of neuroanatomy and neurophysiology.

    Science.gov (United States)

    Slominski, Tara N; Momsen, Jennifer L; Montplaisir, Lisa M

    2017-06-01

    Drawings are an underutilized assessment format in Human Anatomy and Physiology (HA&P), despite their potential to reveal student content understanding and alternative conceptions. This study used student-generated drawings to explore student knowledge in a HA&P course. The drawing tasks in this study focused on chemical synapses between neurons, an abstract concept in HA&P. Using two preinstruction drawing tasks, students were asked to depict synaptic transmission and summation. In response to the first drawing task, 20% of students ( n = 352) created accurate representations of neuron anatomy. The remaining students created drawings suggesting an inaccurate or incomplete understanding of synaptic transmission. Of the 208 inaccurate student-generated drawings, 21% depicted the neurons as touching. When asked to illustrate summation, only 10 students (roughly 4%) were able to produce an accurate drawing. Overall, students were more successful at drawing anatomy (synapse) than physiology (summation) before formal instruction. The common errors observed in student-generated drawings indicate students do not enter the classroom as blank slates. The error of "touching" neurons in a chemical synapse suggests that students may be using intuitive or experiential knowledge when reasoning about physiological concepts. These results 1 ) support the utility of drawing tasks as a tool to reveal student content knowledge about neuroanatomy and neurophysiology; and 2 ) suggest students enter the classroom with better knowledge of anatomy than physiology. Collectively, the findings from this study inform both practitioners and researchers about the prevalence and nature of student difficulties in HA&P, while also demonstrating the utility of drawing in revealing student knowledge. Copyright © 2017 the American Physiological Society.

  12. A skin-picking disorder case report: a psychopathological explanation

    Directory of Open Access Journals (Sweden)

    Ângela Ribeiro

    2015-06-01

    Full Text Available We describe the case of a 44-year-old woman, without known previous psychiatric history, hospitalized after a significant hemorrhage caused by self-inflicted deep facial dermal lesions (with muscle exposition. Psychopathological possible explanations of this case, as in similar reviewed ones, are related to frustration, aggression, and impulsivity.

  13. A Self-Categorization Explanation for the Third-Person Effect

    Science.gov (United States)

    Reid, Scott A.; Hogg, Michael A.

    2005-01-01

    Three studies tested a self-categorization theory explanation for the third-person effect. In Study 1 (N = 49) undergraduate students judged the influence of the "National Enquirer," "Wall Street Journal," and TV show "Friends" on themselves, relative to low- and high-status outgroup members, and other undergraduate students. The profile of first-…

  14. Explanations of Freud's Psychoanalysis Theories on the Lives and ...

    African Journals Online (AJOL)

    This paper examines some of the various explanations of Freud's theories on a selected number of Western Artist and their works. It highlights the impact of his findings on the authenticity of the concept as regards, dreams, the Oedipus complex and imagery. Its objective is to prove that a number of Western European artist ...

  15. Neurophysiological Effects of Chronic Indoor Environmental Toxic Mold Exposure on Children

    Directory of Open Access Journals (Sweden)

    Ebere C. Anyanwu

    2003-01-01

    Full Text Available The phenomenon of building-related diseases is attracting much research interest in recent years because of the extent to which it affects people with compromised immune systems, especially children. In this study, we reported the neurological findings in children who attended our Center because of chronic exposure to toxic molds. Clinical neurological and neurobehavioral questionnaires were administered with the cooperation of the children�s parents. The children then underwent a series of neurophysiological tests including electroencephalogram (EEG, brainstem evoked potential (BAEP, visual evoked potential (VEP, and somatosensory evoked potential (SSEP. The results showed high levels of abnormalities in the analysis of the subjective responses derived from the questionnaires. The EEG examination was abnormal in seven out of ten of the patients compared to the controls with only one in ten with episodes of bihemispheric sharp activity. In all the patients, there was frontotemporal theta wave ativity that seemed to indicate diffuse changes characteristic of metabolic encephalopathies. Also, there was highly marked 1 to 3 Hz delta activity that was asymmetrical in the right hemisphere of the brain in three out of ten patients. The waveforms of BAEP showed abnormalities in 90% of the patients with both 15’ and 31’ check sizes compared to none in the controls. There were significant delays in waveform V in a majority of the patients representing dysfunctional cognitive process and conductive hearing loss in both ears. VEP showed clear abnormalities in four in ten of the patients with P100 amplitudes and latencies decreased bilaterally. In all the patients, there was slowing of conduction in the right tibial at an average of 36.9 ms and there was significant decrease in amplitude of response at the proximal stimulation site. Sensory latencies obtained in the median, ulnar, and sural nerves bilaterally showed abnormalities in five out of ten

  16. Assessment and comparison of culturally based explanations for mental disorder among Singaporean Chinese youth.

    Science.gov (United States)

    Mathews, Mathew

    2011-01-01

    Culture is important to how populations understand the cause of mental disorder, a variable that has implications for treatment-seeking behaviour. Asian populations underutilize professional mental health treatment partly because of their endorsement of supernatural causation models to explain mental disorders, beliefs that stem from their religious backgrounds. This study sought to understand the dimensions of explanatory models used by three groups of Singaporean Chinese youth (n = 842)--Christian, Chinese religionist, no religion--and examined their responses to an instrument that combined explanations from psychological and organic perspectives on mental disorder with approaches from Asian and Western religious traditions. Factor analysis revealed five factors. Two were psychological corresponding to the humanistic and cognitive-behavioural perspectives respectively. Another two, which were supernatural in nature, dealt with karmaic beliefs popular among Asian religionists and more classical religious explanations common in monotheistic religions. The remaining factor was deemed a physiological model although it incorporated an item that made it consistent with an Asian organic model. While groups differed in their endorsement of supernatural explanations, psychological perspectives had the strongest endorsement among this population. Regression analysis showed that individuals who endorsed supernatural explanations more strongly tended to have no exposure to psychology courses and heightened religiosity.

  17. Why Sketching May Aid Learning From Science Texts: Contrasting Sketching With Written Explanations.

    Science.gov (United States)

    Scheiter, Katharina; Schleinschok, Katrin; Ainsworth, Shaaron

    2017-10-01

    The goal of this study was to explore two accounts for why sketching during learning from text is helpful: (1) sketching acts like other constructive strategies such as self-explanation because it helps learners to identify relevant information and generate inferences; or (2) that in addition to these general effects, sketching has more specific benefits due to the pictorial representation that is constructed. Seventy-three seventh-graders (32 girls, M = 12.82 years) were first taught how to either create sketches or self-explain while studying science texts. During a subsequent learning phase, all students were asked to read an expository text about the greenhouse effect. Finally, they were asked to write down everything they remembered and then answer transfer questions. Strategy quality during learning was assessed as the number of key concepts that had either been sketched or mentioned in the self-explanations. The results showed that at an overall performance level there were only marginal group differences. However, a more in-depth analysis revealed that whereas no group differences emerged for students implementing either strategy poorly, the sketching group clearly outperformed the self-explanation group for students who applied the strategies with higher quality. Furthermore, higher sketching quality was strongly related to better learning outcomes. Thus, the study's results are more in line with the second account: Sketching can have a beneficial effect on learning above and beyond generating written explanations; at least, if well deployed. Copyright © 2017 Cognitive Science Society, Inc.

  18. Indexing and Exploiting a Discourse History to Generate Context-Sensitive Explanations

    National Research Council Canada - National Science Library

    Moore, Johanna D

    1993-01-01

    ... to their own previous explanations. Based on a study of human-human instructional inter- actions, we are categorizing the uses of previous discourse and are developing a computational model of this behavior...

  19. Children balance theories and evidence in exploration, explanation, and learning

    NARCIS (Netherlands)

    Bonawitz, E.B.; van Schijndel, T.J.P.; Friel, D.; Schulz, L.

    2012-01-01

    We look at the effect of evidence and prior beliefs on exploration, explanation and learning. In Experiment 1, we tested children both with and without differential prior beliefs about balance relationships (Center Theorists, mean: 82 months; Mass Theorists, mean: 89 months; No Theory children,

  20. The Importance of Qualitative Research for Causal Explanation in Education

    Science.gov (United States)

    Maxwell, Joseph A.

    2012-01-01

    The concept of causation has long been controversial in qualitative research, and many qualitative researchers have rejected causal explanation as incompatible with an interpretivist or constructivist approach. This rejection conflates causation with the positivist "theory" of causation, and ignores an alternative understanding of causation,…

  1. Social class, psychosocial factors and disease : from deception towards explanation.

    NARCIS (Netherlands)

    Ranchor, Adelita Vijaynti

    1994-01-01

    This thesis deals with the question of the extent to which socioeconomic status (sas) is related to disease. The main focus is the explanation of this relation, applying a muitifactor approach aimed at the integration of socioeconomic, psychosocial factors and health-related behavior. ... Zie:

  2. Generalizing the order and the parameters of macro-operators by explanation-based learning - Extension of Explanation-Based Learning on Partial Order

    International Nuclear Information System (INIS)

    Li, Huihua

    1992-01-01

    The traditional generalization methods such as FIKE's macro-operator learning and Explanation-Based Learning (EBL) deal with totally ordered plans. They generalize only the plan operators and the conditions under which the generalized plan can be applied in its initial total order, but not the partial order among operators in which the generalized plan can be successfully executed. In this paper, we extend the notion of the EBL on the partial order of plans. A new method is presented for learning, from a totally or partially ordered plan, partially ordered macro-operators (generalized plans) each of which requires a set of the weakest conditions for its reuse. It is also valuable for generalizing partially ordered plans. The operators are generalized in the FIKE's triangle table. We introduce the domain axioms to generate the constraints for the consistency of generalized states. After completing the triangle table with the information concerning the operator destructions (interactions), we obtain the global explanation of the partial order on the operators. Then, we represent all the necessary ordering relations by a directed graph. The exploitation of this graph permits to explicate the dependence between the partial orders and the constraints among the parameters of generalized operators, and allows all the solutions to be obtained. (author) [fr

  3. Specific properties of the SI and SII somatosensory areas and their effects on motor control: a system neurophysiological study.

    Science.gov (United States)

    Friedrich, Julia; Mückschel, Moritz; Beste, Christian

    2018-03-01

    Sensorimotor integration is essential for successful motor control and the somatosensory modality has been shown to have strong effects on the execution of motor plans. The primary (SI) and the secondary somatosensory (SII) cortices are known to differ in their neuroanatomical connections to prefrontal areas, as well as in their involvement to encode cognitive aspects of tactile processing. Here, we ask whether the area-specific processing architecture or the structural neuroanatomical connections with prefrontal areas determine the efficacy of sensorimotor integration processes for motor control. In a system neurophysiological study including EEG signal decomposition (i.e., residue iteration decomposition, RIDE) and source localization, we investigated this question using vibrotactile stimuli optimized for SI or SII processing. The behavioral data show that when being triggered via the SI area, inhibitory control of motor processes is stronger as when being triggered via the SII area. On a neurophysiological level, these effects were reflected in the C-cluster as a result of a temporal decomposition of EEG data, indicating that the sensory processes affecting motor inhibition modulate the response selection level. These modulations were associated with a stronger activation of the right inferior frontal gyrus extending to the right middle frontal gyrus as parts of a network known to be involved in inhibitory motor control when response inhibition is triggered over SI. In addition, areas important for sensorimotor integration like the postcentral gyrus and superior parietal cortex showed activation differences. The data suggest that connection patterns are more important for sensorimotor integration and control than the more restricted area-specific processing architecture.

  4. Differential Motor Neuron Impairment and Axonal Regeneration in Sporadic and Familiar Amyotrophic Lateral Sclerosis with SOD-1 Mutations: Lessons from Neurophysiology

    OpenAIRE

    Bocci, Tommaso; Pecori, Chiara; Giorli, Elisa; Briscese, Lucia; Tognazzi, Silvia; Caleo, Matteo; Sartucci, Ferdinando

    2011-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a degenerative disorder of the motor system. About 10% of cases are familial and 20% of these families have point mutations in the Cu/Zn superoxide dismutase 1 (SOD-1) gene. SOD-1 catalyses the superoxide radical (O−2) into hydrogen peroxide and molecular oxygen. The clinical neurophysiology in ALS plays a fundamental role in differential diagnosis between the familial and sporadic forms and in the assessment of its severity and progression. Sixty ALS pa...

  5. 46 CFR Appendix II to Part 150 - Explanation of Figure 1

    Science.gov (United States)

    2010-10-01

    ... COMPATIBILITY OF CARGOES Pt. 150, App. II Appendix II to Part 150—Explanation of Figure 1 Definition of a..., aromatic hydrocarbons or paraffins. Others will form hazardous combinations with many groups: For example...

  6. Preoperative and intraoperative neurophysiological investigations for surgical resections in functional areas.

    Science.gov (United States)

    Huberfeld, G; Trébuchon, A; Capelle, L; Badier, J-M; Chen, S; Lefaucheur, J-P; Gavaret, M

    2017-06-01

    Brain regions are removed to treat lesions, but great care must be taken not to disturb or remove functional areas in the lesion and in surrounding tissue where healthy and diseased cells may be intermingled, especially for infiltrating tumors. Cortical functional areas and fiber tracts can be localized preoperatively by probabilistic anatomical tools, but mapping of functional integrity by neurophysiology is essential. Identification of the primary motor cortex seems to be more effectively performed with transcranial magnetic stimulation (TMS) than functional magnetic resonance imaging (fMRI). Language area localization requires auditory evoked potentials or TMS, as well as fMRI and diffusion tensor imaging for fiber tracts. Somatosensory cortex is most effectively mapped by somatosensory evoked potentials. Crucial eloquent areas, such as the central sulcus, primary somatomotor areas, corticospinal tract must be defined and for some areas that must be removed, potential compensations may be identified. Oncological/functional ratio must be optimized, resecting the tumor maximally but also sparingly, as far as possible, the areas that mediate indispensable functions. In some cases, a transient postoperative deficit may be inevitable. In this article, we review intraoperative exploration of motricity, language, somatosensory, visual and vestibular function, calculation, memory and components of consciousness. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. Clinical Neurophysiology Training in a Developing Country: Institutional Resources and Profiles.

    Science.gov (United States)

    Sámano, Arturo G; Ochoa Mena, José D; Padilla, Silvana P; Acevedo, Gerardo R; Orenday Barraza, José M; San-Juan, Daniel

    2018-05-01

    The purpose of this study was to describe the characteristics and preferences of clinical neurophysiology (CN) fellows, as well as the resources available for their training, in a developing country such as Mexico. An online survey (25 questions) was given to Mexican CN fellows from May to June 2017, covering their reasons for choosing the CN subspecialty, their activities, future plans, institutional resources, and administrative staff. Descriptive statistics were used. Total respondents: 20/22 (90%), 65% female from 7 CN centers (80% public and 20% private hospitals) in Mexico City. Seventy-five percent chose CN out of personal interest, and all were not unsatisfied with their academic program. Most plan to work in private practice (75%) and are interested in learning EEG (85%) and intraoperative monitoring (75%-85%). The highest-reported training time by CN area allocated by the programs was as follows: EEG (27%), electromyography (22%), and evoked potentials (16%). The average number of fellows per center was 4; 75% of the centers perform epilepsy surgery, of which 60% offer invasive intracranial studies for the evaluation of surgical candidates. Mexican CN fellows are satisfied with their choice and with the academic program. They are increasingly interested in intraoperative monitoring, which is not addressed in current Mexican CN Programs.

  8. A network-level explanation for the differences in HIV prevalence in ...

    African Journals Online (AJOL)

    A network-level explanation for the differences in HIV prevalence in South Africa's ... or ethnic groups may help explain the differential spread of HIV in South Africa. ... Keywords: concurrency, epidemiology, ethnicity, HIV/AIDS, race, social ...

  9. The Different Effects of Family on Objective Career Success across Gender: A Test of Alternative Explanations

    Science.gov (United States)

    Kirchmeyer, Catherine

    2006-01-01

    Gender gaps in achieved rank and salary, common indicators of objective success, often are attributed to the different family roles and responsibilities of men and women. This study tested three explanations for the different effects of family on careers: that is, choice, performance, and signaling explanations. In a sample of American doctoral…

  10. Designing Automated Guidance to Promote Productive Revision of Science Explanations

    Science.gov (United States)

    Tansomboon, Charissa; Gerard, Libby F.; Vitale, Jonathan M.; Linn, Marcia C.

    2017-01-01

    Supporting students to revise their written explanations in science can help students to integrate disparate ideas and develop a coherent, generative account of complex scientific topics. Using natural language processing to analyze student written work, we compare forms of automated guidance designed to motivate productive revision and help…

  11. A hadronic explanation of the lepton anomaly

    DEFF Research Database (Denmark)

    Mertsch, Philipp; Sarkar, Subir

    2014-01-01

    The rise in the positron fraction, observed by PAMELA, Fermi-LAT and most recently by AMS-02, has created a lot of interest, fuelled by speculations about an origin in dark matter annihilation in the Galactic halo. However, other channels, e.g. antiprotons or gamma-rays, now severely constrain dark....... This mechanism is guaranteed if hadronic CRs are present and would also lead to observable signatures in other secondary channels like the boron-to-carbon or antiproton-to-proton ratios. If such features were borne out by upcoming AMS-02 data, this would rule out other explanations....

  12. A Critique of the Meta-theoretical Explanations and Analyses of the ...

    African Journals Online (AJOL)

    conditions for the Stimulation and Attraction of Foreign Direct Investments. ... these explanations and analyses are able to sufficiently account for, and capture the critical forces, processes and factors that tend to shape the movement of capital globally.

  13. Generalized procedures for determining inspection sample sizes (related to quantitative measurements). Vol. 1: Detailed explanations

    International Nuclear Information System (INIS)

    Jaech, J.L.; Lemaire, R.J.

    1986-11-01

    Generalized procedures have been developed to determine sample sizes in connection with the planning of inspection activities. These procedures are based on different measurement methods. They are applied mainly to Bulk Handling Facilities and Physical Inventory Verifications. The present report attempts (i) to assign to appropriate statistical testers (viz. testers for gross, partial and small defects) the measurement methods to be used, and (ii) to associate the measurement uncertainties with the sample sizes required for verification. Working papers are also provided to assist in the application of the procedures. This volume contains the detailed explanations concerning the above mentioned procedures

  14. On the electrodynamic explanation of the retrograde motion of the electric arc

    International Nuclear Information System (INIS)

    Hong, J.S.; Allen, J.E.

    1992-01-01

    The retrograde motion of the cathode spot in a transverse magnetic field is one of the more intriguing phenomena of the electric arc. Although the phenomenon has been known for nearly ninety years since its discovery by Stark and has stimulated numerous investigations which result in many models giving explanation from different points of view, there is still no theory that can account both qualitatively and quantitatively for all the observations. Most of the explanations of the retrograde motion involve the study of cathode processes to give the preferential formation of new cathode spots along the retrograde direction. One line of explanation, which is rather different from the others, is based on electrodynamics. In this approach the retrograde motion is treated as an electrodynamic event. The present paper develops the theory suggested by Robson and von Engel. A more complete model is proposed and studied in detail by means of electromagnetic field theory. The results obtained not only show that the retrograde motion can be explained by the electrodynamics, but also confirm that the average current density on the cathode spot must be around the order of 10 12 A/m 2 . Recent studies of spot current density have shown values of this order. (author) 22 refs., 4 figs., 1 tab

  15. Misconceptions about optics: An effect of misleading explanations?

    Science.gov (United States)

    Favale, Fabrizio; Bondani, Maria

    2014-07-01

    During our activities of physics dissemination with High School students especially concerning optics, we are used to distribute a questionnaire about colors and image formation by mirrors and lenses. The answers to some questions clearly show misconceptions and naïve ideas about colors, ray tracing, image formation in reflection and refraction. These misconceptions are widespread and do not depend on the gender, the level, and the age of the students: they seem to depend on some wrong ideas and explanatory models that are not changed by the curricular studies at school. In fact, the same errors are present in groups of students before and after taking optics courses at High School. On the other hand we have also found some misleading explanations of the phenomena both in textbooks and websites. Most of the time, errors occur in the explanatory drawings accompanying the text, which are based on some hybrid description of the optical processes: sometimes the description of the path of the ray light is confused with the image reconstruction by the lenses. We think that to partially avoid some errors it is important to use a teaching path centered on the actual path of the rays and not on what eyes see (the vision). Here we present the results of data collected from more than 200 students and some considerations about figures and explanations found in textbooks.

  16. An explanation of the mysterious quasars

    International Nuclear Information System (INIS)

    Borissov, O.

    1977-01-01

    The article presents details of a convincing new theory submitted by Russian scientists, concerning the physical nature of quasars. These were discovered in 1963 and for over ten years no satisfactory theory has been forthcoming to explain their seemingly incompatible properties or the associated phenomena. These very distant objects are believed to be sources of the most powerful electromagnetic emission. From the new theory expounded it is concluded that for the first time since their discovery a satisfactory explanation of their nature has been reached. From this it is hoped that the mechanism of energy generation by quasars may ultimately be understood and, though on a much reduced scale, contribute to the solution of energy problems on earth. (R.J.J.)

  17. Experience and Explanation: Using Videogames to Prepare Students for Formal Instruction in Statistics

    Science.gov (United States)

    Arena, Dylan A.; Schwartz, Daniel L.

    2014-08-01

    Well-designed digital games can deliver powerful experiences that are difficult to provide through traditional instruction, while traditional instruction can deliver formal explanations that are not a natural fit for gameplay. Combined, they can accomplish more than either can alone. An experiment tested this claim using the topic of statistics, where people's everyday experiences often conflict with normative statistical theories and a videogame might provide an alternate set of experiences for students to draw upon. The research used a game called Stats Invaders!, a variant of the classic videogame Space Invaders. In Stats Invaders!, the locations of descending alien invaders follow probability distributions, and players need to infer the shape of the distributions to play well. The experiment tested whether the game developed participants' intuitions about the structure of random events and thereby prepared them for future learning from a subsequent written passage on probability distributions. Community-college students who played the game and then read the passage learned more than participants who only read the passage.

  18. Older persons' definitions and explanations of elder abuse in the Netherlands

    DEFF Research Database (Denmark)

    Mysyuk, Yuliya; Westendorp, Rudi G J; Lindenberg, Jolanda

    2016-01-01

    persons in society, which result in disrespect toward older persons and a lack of social control and responsibility. The older persons' explanations for the occurrence of abuse mainly focus on societal changes; older persons seem to regard elder abuse primarily as a societal problem. This understanding of......In this article we explore older persons' definitions of and explanations for elder abuse in the Netherlands by means of interviews with older persons. A qualitative study was conducted based on semi-structured interviews with 35 older persons who had no experience with abuse. Our findings show...... that older persons participating in our study define elder abuse foremost as physical violence that is performed intentionally. The study participants explain elder abuse as a result of the dependency and vulnerability of older persons, of changing norms and values, and of changes in the position of older...

  19. The discourse of causal explanations in school science

    Science.gov (United States)

    Slater, Tammy Jayne Anne

    Researchers and educators working from a systemic functional linguistic perspective have provided a body of work on science discourse which offers an excellent starting point for examining the linguistic aspects of the development of causal discourse in school science, discourse which Derewianka (1995) claimed is critical to success in secondary school. No work has yet described the development of causal language by identifying the linguistic features present in oral discourse or by comparing the causal discourse of native and non-native (ESL) speakers of English. The current research responds to this gap by examining the oral discourse collected from ESL and non-ESL students at the primary and high school grades. Specifically, it asks the following questions: (1) How do the teachers and students in these four contexts develop causal explanations and their relevant taxonomies through classroom interactions? (2) What are the causal discourse features being used by the students in these four contexts to construct oral causal explanations? The findings of the social practice analysis showed that the teachers in the four contexts differed in their approaches to teaching, with the primary school mainstream teacher focusing largely on the hands-on practice , the primary school ESL teacher moving from practice to theory, the high school mainstream teacher moving from theory to practice, and the high school ESL teacher relying primarily on theory. The findings from the quantitative, small corpus approach suggest that the developmental path of cause which has been identified in the writing of experts shows up not only in written texts but also in the oral texts which learners construct. Moreover, this move appears when the discourse of high school ESL and non-ESL students is compared, suggesting a developmental progression in the acquisition of these features by these students. The findings also reveal that the knowledge constructed, as shown by the concept maps created

  20. Rhythm in joint action: psychological and neurophysiological mechanisms for real-time interpersonal coordination

    Science.gov (United States)

    Keller, Peter E.; Novembre, Giacomo; Hove, Michael J.

    2014-01-01

    Human interaction often requires simultaneous precision and flexibility in the coordination of rhythmic behaviour between individuals engaged in joint activity, for example, playing a musical duet or dancing with a partner. This review article addresses the psychological processes and brain mechanisms that enable such rhythmic interpersonal coordination. First, an overview is given of research on the cognitive-motor processes that enable individuals to represent joint action goals and to anticipate, attend and adapt to other's actions in real time. Second, the neurophysiological mechanisms that underpin rhythmic interpersonal coordination are sought in studies of sensorimotor and cognitive processes that play a role in the representation and integration of self- and other-related actions within and between individuals' brains. Finally, relationships between social–psychological factors and rhythmic interpersonal coordination are considered from two perspectives, one concerning how social-cognitive tendencies (e.g. empathy) affect coordination, and the other concerning how coordination affects interpersonal affiliation, trust and prosocial behaviour. Our review highlights musical ensemble performance as an ecologically valid yet readily controlled domain for investigating rhythm in joint action. PMID:25385772