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Sample records for temporal brain code

  1. A Plastic Temporal Brain Code for Conscious State Generation

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    Birgitta Dresp-Langley

    2009-01-01

    Full Text Available Consciousness is known to be limited in processing capacity and often described in terms of a unique processing stream across a single dimension: time. In this paper, we discuss a purely temporal pattern code, functionally decoupled from spatial signals, for conscious state generation in the brain. Arguments in favour of such a code include Dehaene et al.'s long-distance reverberation postulate, Ramachandran's remapping hypothesis, evidence for a temporal coherence index and coincidence detectors, and Grossberg's Adaptive Resonance Theory. A time-bin resonance model is developed, where temporal signatures of conscious states are generated on the basis of signal reverberation across large distances in highly plastic neural circuits. The temporal signatures are delivered by neural activity patterns which, beyond a certain statistical threshold, activate, maintain, and terminate a conscious brain state like a bar code would activate, maintain, or inactivate the electronic locks of a safe. Such temporal resonance would reflect a higher level of neural processing, independent from sensorial or perceptual brain mechanisms.

  2. Spatial-temporal transcriptional dynamics of long non-coding RNAs in human brain.

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    Zhang, Xiao-Qin; Wang, Ze-Lin; Poon, Ming-Wai; Yang, Jian-Hua

    2017-08-15

    The functional architecture of the human brain is greatly determined by the temporal and spatial regulation of the transcription process. However, the spatial and temporal transcriptional landscape of long non-coding RNAs (lncRNAs) during human brain development remains poorly understood. Here, we report the genome-wide lncRNA transcriptional analysis in an extensive series of 1340 post-mortem human brain specimens collected from 16 regions spanning the period from early embryo development to late adulthood. We discovered that lncRNA transcriptome dramatically changed during fetal development, while transited to a surprisingly relatively stable state after birth till the late adulthood. We also discovered that the transcription map of lncRNAs was spatially different, and that this spatial difference was developmentally regulated. Of the 16 brain regions explored (cerebellar cortex, thalamus, striatum, amygdala, hippocampus and 11 neocortex areas), cerebellar cortex showed the most distinct lncRNA expression features from all remaining brain regions throughout the whole developmental period, reflecting its unique developmental and functional features. Furthermore, by characterizing the functional modules and cellular processes of the spatial-temporal dynamic lncRNAs, we found that they were significantly associated with the RNA processing, neuron differentiation and synaptic signal transportation processes. Furthermore, we found that many lncRNAs associated with the neurodegenerative Alzheimer and Parkinson diseases were co-expressed in the fetal development of the human brain, and affected the convergent biological processes. In summary, our study provides a comprehensive map for lncRNA transcription dynamics in human brain development, which might shed light on the understanding of the molecular underpinnings of human brain function and disease. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Temporal coding of brain patterns for direct limb control in humans

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    Gernot Mueller-Putz

    2010-06-01

    Full Text Available For individuals with a high spinal cord injury (SCI not only the lower limbs, but also the upper extremities are paralyzed. A neuroprosthesis can be used to restore the lost hand and arm function in those tetraplegics. The main problem for this group of individuals, however, is the reduced ability to voluntarily operate device controllers. A Brain-Computer Interface provides a non-manual alternative to conventional input devices by translating brain activity patterns into control commands. We show that the temporal coding of individual mental imagery pattern can be used to control two independent degrees of freedom – grasp and elbow function - of an artificial robotic arm by utilizing a minimum number of EEG scalp electrodes. We describe the procedure from the initial screening to the final application. From eight naïve subjects participating on-line feedback experiments, four were able to voluntarily control an artificial arm by inducing one motor imagery pattern derived from one EEG derivation only.

  4. Temporal Coding of Volumetric Imagery

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    Llull, Patrick Ryan

    'Image volumes' refer to realizations of images in other dimensions such as time, spectrum, and focus. Recent advances in scientific, medical, and consumer applications demand improvements in image volume capture. Though image volume acquisition continues to advance, it maintains the same sampling mechanisms that have been used for decades; every voxel must be scanned and is presumed independent of its neighbors. Under these conditions, improving performance comes at the cost of increased system complexity, data rates, and power consumption. This dissertation explores systems and methods capable of efficiently improving sensitivity and performance for image volume cameras, and specifically proposes several sampling strategies that utilize temporal coding to improve imaging system performance and enhance our awareness for a variety of dynamic applications. Video cameras and camcorders sample the video volume (x,y,t) at fixed intervals to gain understanding of the volume's temporal evolution. Conventionally, one must reduce the spatial resolution to increase the framerate of such cameras. Using temporal coding via physical translation of an optical element known as a coded aperture, the compressive temporal imaging (CACTI) camera emonstrates a method which which to embed the temporal dimension of the video volume into spatial (x,y) measurements, thereby greatly improving temporal resolution with minimal loss of spatial resolution. This technique, which is among a family of compressive sampling strategies developed at Duke University, temporally codes the exposure readout functions at the pixel level. Since video cameras nominally integrate the remaining image volume dimensions (e.g. spectrum and focus) at capture time, spectral (x,y,t,lambda) and focal (x,y,t,z) image volumes are traditionally captured via sequential changes to the spectral and focal state of the system, respectively. The CACTI camera's ability to embed video volumes into images leads to exploration

  5. Coding of multisensory temporal patterns in human superior temporal sulcus

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    Toemme eNoesselt

    2012-08-01

    Full Text Available Philosophers, psychologists, and neuroscientists have long been interested in how the temporal aspects of perception are represented in the brain. In the present study, we investigated the neural basis of the temporal perception of synchrony/asynchrony for audiovisual speech stimuli using functional magnetic imaging (fMRI. Subjects judged the temporal relation of (asynchronous audiovisual speech streams, and indicated any changes in their perception of the stimuli over time. Differential hemodynamic responses for synchronous versus asynchronous stimuli were observed in the multisensory superior temporal sulcus complex (mSTS-c and prefrontal cortex. Within mSTS-c we found adjacent regions expressing an enhanced BOLD-response to the different physical (asynchrony conditions. These regions were further modulated by the subjects’ perceptual state. By calculating the distances between the modulated regions within mSTS-c in single-subjects we demonstrate that the ‘auditory’ and ‘visual leading areas’ lie closer to ‘synchrony areas’ than to each other. Moreover, analysis of interregional connectivity indicates a stronger functional connection between multisensory prefrontal cortex and mSTS-c during the perception of asynchrony. Taken together, these results therefore suggest the presence of distinct sub-regions within the human STS-c for the maintenance of temporal relations for audiovisual speech stimuli plus differential functional connectivity with prefrontal regions. The respective local activity in mSTS-c is dependent both upon the physical properties of the stimuli presented and upon the subjects’ perception of (asynchrony.

  6. Coding of multisensory temporal patterns in human superior temporal sulcus.

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    Noesselt, Tömme; Bergmann, Daniel; Heinze, Hans-Jochen; Münte, Thomas; Spence, Charles

    2012-01-01

    Philosophers, psychologists, and neuroscientists have long been interested in how the temporal aspects of perception are represented in the brain. In the present study, we investigated the neural basis of the temporal perception of synchrony/asynchrony for audiovisual speech stimuli using functional magnetic resonance imaging (fMRI). Subjects judged the temporal relation of (a)synchronous audiovisual speech streams, and indicated any changes in their perception of the stimuli over time. Differential hemodynamic responses for synchronous versus asynchronous stimuli were observed in the multisensory superior temporal sulcus complex (mSTS-c) and prefrontal cortex. Within mSTS-c we found adjacent regions expressing an enhanced BOLD-response to the different physical (a)synchrony conditions. These regions were further modulated by the subjects' perceptual state. By calculating the distances between the modulated regions within mSTS-c in single-subjects we demonstrate that the "auditory leading (A(L))" and "visual leading (V(L)) areas" lie closer to "synchrony areas" than to each other. Moreover, analysis of interregional connectivity indicates a stronger functional connection between multisensory prefrontal cortex and mSTS-c during the perception of asynchrony. Taken together, these results therefore suggest the presence of distinct sub-regions within the human STS-c for the maintenance of temporal relations for audiovisual speech stimuli plus differential functional connectivity with prefrontal regions. The respective local activity in mSTS-c is dependent both upon the physical properties of the stimuli presented and upon the subjects' perception of (a)synchrony.

  7. Brain SPECT imaging in temporal lobe epilepsy

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    Krausz, Y.; Yaffe, S.; Atlan, H. (Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Medical Biophysics and Nuclear Medicine); Cohen, D. (Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Radiology); Konstantini, S. (Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Neurosurgery); Meiner, Z. (Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Neurology)

    1991-06-01

    Temporal lobe epilepsy is diagnosed by clinical symptoms and signs and by localization of an epileptogenic focus. A brain SPECT study of two patients with temporal lobe epilepsy, using {sup 99m}Tc-HMPAO, was used to demonstrate a perfusion abnormality in the temporal lobe, while brain CT and MRI were non-contributory. The electroencephalogram, though abnormal, did not localize the diseased area. The potential role of the SPECT study in diagnosis and localization of temporal lobe epilepsy is discussed. (orig.).

  8. Temporal Map Formation in the Barn Owl's Brain

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    Leibold, Christian; Kempter, Richard; van Hemmen, J. Leo

    2001-12-01

    Barn owls provide an experimentally well-specified example of a temporal map, a neuronal representation of the outside world in the brain by means of time. Their laminar nucleus exhibits a place code of interaural time differences, a cue which is used to determine the azimuthal location of a sound stimulus, e.g., prey. We analyze a model of synaptic plasticity that explains the formation of such a representation in the young bird and show how in a large parameter regime a combination of local and nonlocal synaptic plasticity yields the temporal map as found experimentally. Our analysis includes the effect of nonlinearities as well as the influence of neuronal noise.

  9. BrainNet Europe's Code of Conduct for brain banking.

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    Klioueva, Natasja M; Rademaker, Marleen C; Dexter, David T; Al-Sarraj, Safa; Seilhean, Danielle; Streichenberger, Nathalie; Schmitz, Peer; Bell, Jeanne E; Ironside, James W; Arzberger, Thomas; Huitinga, Inge

    2015-07-01

    Research utilizing human tissue and its removal at post-mortem has given rise to many controversies in the media and posed many dilemmas in the fields of law and ethics. The law often lacks clear instructions and unambiguous guidelines. The absence of a harmonized international legislation with regard to post-mortem medical procedures and donation of tissue and organs contributes to the complexity of the issue. Therefore, within the BrainNet Europe (BNE) consortium, a consortium of 19 European brain banks, we drafted an ethical Code of Conduct for brain banking that covers basic legal rules and bioethical principles involved in brain banking. Sources include laws, regulations and guidelines (Declarations, Conventions, Recommendations, Guidelines and Directives) issued by international key organizations, such as the Council of Europe, European Commission, World Medical Association and World Health Organization. The Code of Conduct addresses fundamental topics as the rights of the persons donating their tissue, the obligations of the brain bank with regard to respect and observance of such rights, informed consent, confidentiality, protection of personal data, collections of human biological material and their management, and transparency and accountability within the organization of a brain bank. The Code of Conduct for brain banking is being adopted by the BNE network prior to being enshrined in official legislation for brain banking in Europe and beyond.

  10. Determinants of spatial and temporal coding by semicircular canal afferents.

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    Highstein, Stephen M; Rabbitt, Richard D; Holstein, Gay R; Boyle, Richard D

    2005-05-01

    The vestibular semicircular canals are internal sensors that signal the magnitude, direction, and temporal properties of angular head motion. Fluid mechanics within the 3-canal labyrinth code the direction of movement and integrate angular acceleration stimuli over time. Directional coding is accomplished by decomposition of complex angular accelerations into 3 biomechanical components-one component exciting each of the 3 ampullary organs and associated afferent nerve bundles separately. For low-frequency angular motion stimuli, fluid displacement within each canal is proportional to angular acceleration. At higher frequencies, above the lower corner frequency, real-time integration is accomplished by viscous forces arising from the movement of fluid within the slender lumen of each canal. This results in angular velocity sensitive fluid displacements. Reflecting this, a subset of afferent fibers indeed report angular acceleration to the brain for low frequencies of head movement and report angular velocity for higher frequencies. However, a substantial number of afferent fibers also report angular acceleration, or a signal between acceleration and velocity, even at frequencies where the endolymph displacement is known to follow angular head velocity. These non-velocity-sensitive afferent signals cannot be attributed to canal biomechanics alone. The responses of non-velocity-sensitive cells include a mathematical differentiation (first-order or fractional) imparted by hair-cell and/or afferent complexes. This mathematical differentiation from velocity to acceleration cannot be attributed to hair cell ionic currents, but occurs as a result of the dynamics of synaptic transmission between hair cells and their primary afferent fibers. The evidence for this conclusion is reviewed below.

  11. Identifying temporal codes in spontaneously active sensory neurons.

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    Alexander B Neiman

    Full Text Available The manner in which information is encoded in neural signals is a major issue in Neuroscience. A common distinction is between rate codes, where information in neural responses is encoded as the number of spikes within a specified time frame (encoding window, and temporal codes, where the position of spikes within the encoding window carries some or all of the information about the stimulus. One test for the existence of a temporal code in neural responses is to add artificial time jitter to each spike in the response, and then assess whether or not information in the response has been degraded. If so, temporal encoding might be inferred, on the assumption that the jitter is small enough to alter the position, but not the number, of spikes within the encoding window. Here, the effects of artificial jitter on various spike train and information metrics were derived analytically, and this theory was validated using data from afferent neurons of the turtle vestibular and paddlefish electrosensory systems, and from model neurons. We demonstrate that the jitter procedure will degrade information content even when coding is known to be entirely by rate. For this and additional reasons, we conclude that the jitter procedure by itself is not sufficient to establish the presence of a temporal code.

  12. Differential DNA methylation profiles of coding and non-coding genes define hippocampal sclerosis in human temporal lobe epilepsy.

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    Miller-Delaney, Suzanne F C; Bryan, Kenneth; Das, Sudipto; McKiernan, Ross C; Bray, Isabella M; Reynolds, James P; Gwinn, Ryder; Stallings, Raymond L; Henshall, David C

    2015-03-01

    Temporal lobe epilepsy is associated with large-scale, wide-ranging changes in gene expression in the hippocampus. Epigenetic changes to DNA are attractive mechanisms to explain the sustained hyperexcitability of chronic epilepsy. Here, through methylation analysis of all annotated C-phosphate-G islands and promoter regions in the human genome, we report a pilot study of the methylation profiles of temporal lobe epilepsy with or without hippocampal sclerosis. Furthermore, by comparative analysis of expression and promoter methylation, we identify methylation sensitive non-coding RNA in human temporal lobe epilepsy. A total of 146 protein-coding genes exhibited altered DNA methylation in temporal lobe epilepsy hippocampus (n = 9) when compared to control (n = 5), with 81.5% of the promoters of these genes displaying hypermethylation. Unique methylation profiles were evident in temporal lobe epilepsy with or without hippocampal sclerosis, in addition to a common methylation profile regardless of pathology grade. Gene ontology terms associated with development, neuron remodelling and neuron maturation were over-represented in the methylation profile of Watson Grade 1 samples (mild hippocampal sclerosis). In addition to genes associated with neuronal, neurotransmitter/synaptic transmission and cell death functions, differential hypermethylation of genes associated with transcriptional regulation was evident in temporal lobe epilepsy, but overall few genes previously associated with epilepsy were among the differentially methylated. Finally, a panel of 13, methylation-sensitive microRNA were identified in temporal lobe epilepsy including MIR27A, miR-193a-5p (MIR193A) and miR-876-3p (MIR876), and the differential methylation of long non-coding RNA documented for the first time. The present study therefore reports select, genome-wide DNA methylation changes in human temporal lobe epilepsy that may contribute to the molecular architecture of the epileptic brain. © The

  13. Temporal Organization of the Brain: Neurocognitive Mechanisms and Clinical Implications

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    Dawson, Kim A.

    2004-01-01

    The synchrony between the individual brain and its environment is maintained by a system of internal clocks that together reflect the temporal organization of the organism. Extending the theoretical work of Edelman and others, the temporal organization of the brain is posited as functioning through "'re-entry" and "'temporal tagging"' and binds…

  14. Face coding is bilateral in the female brain.

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    Alice Mado Proverbio

    Full Text Available BACKGROUND: It is currently believed that face processing predominantly activates the right hemisphere in humans, but available literature is very inconsistent. METHODOLOGY/PRINCIPAL FINDINGS: In this study, ERPs were recorded in 50 right-handed women and men in response to 390 faces (of different age and sex, and 130 technological objects. Results showed no sex difference in the amplitude of N170 to objects; a much larger face-specific response over the right hemisphere in men, and a bilateral response in women; a lack of face-age coding effect over the left hemisphere in men, with no differences in N170 to faces as a function of age; a significant bilateral face-age coding effect in women. CONCLUSIONS/SIGNIFICANCE: LORETA reconstruction showed a significant left and right asymmetry in the activation of the fusiform gyrus (BA19, in women and men, respectively. The present data reveal a lesser degree of lateralization of brain functions related to face coding in women than men. In this light, they may provide an explanation of the inconsistencies in the available literature concerning the asymmetric activity of left and right occipito-temporal cortices devoted to face perception during processing of face identity, structure, familiarity or affective content.

  15. Face Coding Is Bilateral in the Female Brain

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    Proverbio, Alice Mado; Riva, Federica; Martin, Eleonora; Zani, Alberto

    2010-01-01

    Background It is currently believed that face processing predominantly activates the right hemisphere in humans, but available literature is very inconsistent. Methodology/Principal Findings In this study, ERPs were recorded in 50 right-handed women and men in response to 390 faces (of different age and sex), and 130 technological objects. Results showed no sex difference in the amplitude of N170 to objects; a much larger face-specific response over the right hemisphere in men, and a bilateral response in women; a lack of face-age coding effect over the left hemisphere in men, with no differences in N170 to faces as a function of age; a significant bilateral face-age coding effect in women. Conclusions/Significance LORETA reconstruction showed a significant left and right asymmetry in the activation of the fusiform gyrus (BA19), in women and men, respectively. The present data reveal a lesser degree of lateralization of brain functions related to face coding in women than men. In this light, they may provide an explanation of the inconsistencies in the available literature concerning the asymmetric activity of left and right occipito-temporal cortices devoted to face perception during processing of face identity, structure, familiarity or affective content. PMID:20574528

  16. Distributed processing and temporal codes in neuronal networks.

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    Singer, Wolf

    2009-09-01

    The cerebral cortex presents itself as a distributed dynamical system with the characteristics of a small world network. The neuronal correlates of cognitive and executive processes often appear to consist of the coordinated activity of large assemblies of widely distributed neurons. These features require mechanisms for the selective routing of signals across densely interconnected networks, the flexible and context dependent binding of neuronal groups into functionally coherent assemblies and the task and attention dependent integration of subsystems. In order to implement these mechanisms, it is proposed that neuronal responses should convey two orthogonal messages in parallel. They should indicate (1) the presence of the feature to which they are tuned and (2) with which other neurons (specific target cells or members of a coherent assembly) they are communicating. The first message is encoded in the discharge frequency of the neurons (rate code) and it is proposed that the second message is contained in the precise timing relationships between individual spikes of distributed neurons (temporal code). It is further proposed that these precise timing relations are established either by the timing of external events (stimulus locking) or by internal timing mechanisms. The latter are assumed to consist of an oscillatory modulation of neuronal responses in different frequency bands that cover a broad frequency range from 40 Hz (gamma) and ripples. These oscillations limit the communication of cells to short temporal windows whereby the duration of these windows decreases with oscillation frequency. Thus, by varying the phase relationship between oscillating groups, networks of functionally cooperating neurons can be flexibly configurated within hard wired networks. Moreover, by synchronizing the spikes emitted by neuronal populations, the saliency of their responses can be enhanced due to the coincidence sensitivity of receiving neurons in very much the same way as

  17. Non-coding RNAs in cancer brain metastasis.

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    Wu, Kerui; Sharma, Sambad; Venkat, Suresh; Liu, Keqin; Zhou, Xiaobo; Watabe, Kounosuke

    2016-01-01

    More than 90% of cancer death is attributed to metastatic disease, and the brain is one of the major metastatic sites of melanoma, colon, renal, lung and breast cancers. Despite the recent advancement of targeted therapy for cancer, the incidence of brain metastasis is increasing. One reason is that most therapeutic drugs can't penetrate blood-brain-barrier and tumor cells find the brain as sanctuary site. In this review, we describe the pathophysiology of brain metastases to introduce the latest understandings of metastatic brain malignancies. This review also particularly focuses on non-coding RNAs and their roles in cancer brain metastasis. Furthermore, we discuss the roles of the extracellular vesicles as they are known to transport information between cells to initiate cancer cell-microenvironment communication. The potential clinical translation of non-coding RNAs as a tool for diagnosis and for treatment is also discussed in this review. At the end, the computational aspects of non-coding RNA detection, the sequence and structure calculation and epigenetic regulation of non-coding RNA in brain metastasis are discussed.

  18. Formal learning theory dissociates brain regions with different temporal integration.

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    Gläscher, Jan; Büchel, Christian

    2005-07-21

    Learning can be characterized as the extraction of reliable predictions about stimulus occurrences from past experience. In two experiments, we investigated the interval of temporal integration of previous learning trials in different brain regions using implicit and explicit Pavlovian fear conditioning with a dynamically changing reinforcement regime in an experimental setting. With formal learning theory (the Rescorla-Wagner model), temporal integration is characterized by the learning rate. Using fMRI and this theoretical framework, we are able to distinguish between learning-related brain regions that show long temporal integration (e.g., amygdala) and higher perceptual regions that integrate only over a short period of time (e.g., fusiform face area, parahippocampal place area). This approach allows for the investigation of learning-related changes in brain activation, as it can dissociate brain areas that differ with respect to their integration of past learning experiences by either computing long-term outcome predictions or instantaneous reinforcement expectancies.

  19. A computational model of cellular mechanisms of temporal coding in the medial geniculate body (MGB.

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    Cal F Rabang

    Full Text Available Acoustic stimuli are often represented in the early auditory pathway as patterns of neural activity synchronized to time-varying features. This phase-locking predominates until the level of the medial geniculate body (MGB, where previous studies have identified two main, largely segregated response types: Stimulus-synchronized responses faithfully preserve the temporal coding from its afferent inputs, and Non-synchronized responses, which are not phase locked to the inputs, represent changes in temporal modulation by a rate code. The cellular mechanisms underlying this transformation from phase-locked to rate code are not well understood. We use a computational model of a MGB thalamocortical neuron to test the hypothesis that these response classes arise from inferior colliculus (IC excitatory afferents with divergent properties similar to those observed in brain slice studies. Large-conductance inputs exhibiting synaptic depression preserved input synchrony as short as 12.5 ms interclick intervals, while maintaining low firing rates and low-pass filtering responses. By contrast, small-conductance inputs with Mixed plasticity (depression of AMPA-receptor component and facilitation of NMDA-receptor component desynchronized afferent inputs, generated a click-rate dependent increase in firing rate, and high-pass filtered the inputs. Synaptic inputs with facilitation often permitted band-pass synchrony along with band-pass rate tuning. These responses could be tuned by changes in membrane potential, strength of the NMDA component, and characteristics of synaptic plasticity. These results demonstrate how the same synchronized input spike trains from the inferior colliculus can be transformed into different representations of temporal modulation by divergent synaptic properties.

  20. Diminished temporal coding with sensorineural hearing loss emerges in background noise.

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    Henry, Kenneth S; Heinz, Michael G

    2012-10-01

    Behavioral studies in humans suggest that sensorineural hearing loss (SNHL) decreases sensitivity to the temporal structure of sound, but neurophysiological studies in mammals provide little evidence for diminished temporal coding. We found that SNHL in chinchillas degraded peripheral temporal coding in background noise substantially more than in quiet. These results resolve discrepancies between previous studies and help to explain why perceptual difficulties in hearing-impaired listeners often emerge in noisy situations.

  1. Brain Regions Underlying Word Finding Difficulties in Temporal Lobe Epilepsy

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    Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine

    2009-01-01

    Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance.…

  2. Visually lossless coding based on temporal masking in human vision

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    Adzic, Velibor; Hock, Howard S.; Kalva, Hari

    2014-02-01

    This paper presents a method for perceptual video compression that exploits the phenomenon of backward temporal masking. We present an overview of visual temporal masking and discuss models to identify portions of a video sequences masked due to this phenomenon exhibited by the human visual system. A quantization control model based on the psychophysical model of backward visual temporal masking was developed. We conducted two types of subjective evaluations and demonstrated that the proposed method up to 10% bitrate savings on top of state of the art encoder with visually identical video. The proposed methods were evaluated using HEVC encoder.

  3. Disturbed temporal dynamics of brain synchronization in vision loss.

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    Bola, Michał; Gall, Carolin; Sabel, Bernhard A

    2015-06-01

    Damage along the visual pathway prevents bottom-up visual input from reaching further processing stages and consequently leads to loss of vision. But perception is not a simple bottom-up process - rather it emerges from activity of widespread cortical networks which coordinate visual processing in space and time. Here we set out to study how vision loss affects activity of brain visual networks and how networks' activity is related to perception. Specifically, we focused on studying temporal patterns of brain activity. To this end, resting-state eyes-closed EEG was recorded from partially blind patients suffering from chronic retina and/or optic-nerve damage (n = 19) and healthy controls (n = 13). Amplitude (power) of oscillatory activity and phase locking value (PLV) were used as measures of local and distant synchronization, respectively. Synchronization time series were created for the low- (7-9 Hz) and high-alpha band (11-13 Hz) and analyzed with three measures of temporal patterns: (i) length of synchronized-/desynchronized-periods, (ii) Higuchi Fractal Dimension (HFD), and (iii) Detrended Fluctuation Analysis (DFA). We revealed that patients exhibit less complex, more random and noise-like temporal dynamics of high-alpha band activity. More random temporal patterns were associated with worse performance in static (r = -.54, p = .017) and kinetic perimetry (r = .47, p = .041). We conclude that disturbed temporal patterns of neural synchronization in vision loss patients indicate disrupted communication within brain visual networks caused by prolonged deafferentation. We propose that because the state of brain networks is essential for normal perception, impaired brain synchronization in patients with vision loss might aggravate the functional consequences of reduced visual input. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Spectral properties of the temporal evolution of brain network structure

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    Wang, Rong; Zhang, Zhen-Zhen; Ma, Jun; Yang, Yong; Lin, Pan; Wu, Ying

    2015-12-01

    The temporal evolution properties of the brain network are crucial for complex brain processes. In this paper, we investigate the differences in the dynamic brain network during resting and visual stimulation states in a task-positive subnetwork, task-negative subnetwork, and whole-brain network. The dynamic brain network is first constructed from human functional magnetic resonance imaging data based on the sliding window method, and then the eigenvalues corresponding to the network are calculated. We use eigenvalue analysis to analyze the global properties of eigenvalues and the random matrix theory (RMT) method to measure the local properties. For global properties, the shifting of the eigenvalue distribution and the decrease in the largest eigenvalue are linked to visual stimulation in all networks. For local properties, the short-range correlation in eigenvalues as measured by the nearest neighbor spacing distribution is not always sensitive to visual stimulation. However, the long-range correlation in eigenvalues as evaluated by spectral rigidity and number variance not only predicts the universal behavior of the dynamic brain network but also suggests non-consistent changes in different networks. These results demonstrate that the dynamic brain network is more random for the task-positive subnetwork and whole-brain network under visual stimulation but is more regular for the task-negative subnetwork. Our findings provide deeper insight into the importance of spectral properties in the functional brain network, especially the incomparable role of RMT in revealing the intrinsic properties of complex systems.

  5. Binary temporal upconversion codes of Mn^sup 2+^-activated nanoparticles for multilevel anti-counterfeiting

    National Research Council Canada - National Science Library

    Xiaowang Liu; Yu Wang; Xiyan Li; Zhigao Yi; Renren Deng; Liangliang Liang; Xiaoji Xie; Daniel T B Loong; Shuyan Song; Dianyuan Fan; Angelo H All; Hongjie Zhang; Ling Huang; Xiaogang Liu

    2017-01-01

    .... Here, we demonstrate that integration of long-lived Mn2+ upconversion emission and relatively short-lived lanthanide upconversion emission in a particulate platform allows the generation of binary temporal codes for efficient...

  6. From Brain-Environment Connections to Temporal Dynamics and Social Interaction: Principles of Human Brain Function.

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    Hari, Riitta

    2017-06-07

    Experimental data about brain function accumulate faster than does our understanding of how the brain works. To tackle some general principles at the grain level of behavior, I start from the omnipresent brain-environment connection that forces regularities of the physical world to shape the brain. Based on top-down processing, added by sparse sensory information, people are able to form individual "caricature worlds," which are similar enough to be shared among other people and which allow quick and purposeful reactions to abrupt changes. Temporal dynamics and social interaction in natural environments serve as further essential organizing principles of human brain function. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. The Coding of Temperature in the Drosophila Brain

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    Gallio, Marco; Ofstad, Tyler A.; Macpherson, Lindsey J.; Wang, Jing W.; Zuker, Charles S.

    2011-01-01

    Thermosensation is an indispensable sensory modality. Here, we study temperature coding in Drosophila, and show that temperature is represented by a spatial map of activity in the brain. First, we identify new TRP channels and demonstrate they function in the fly antenna to mediate the detection of cold stimuli. Next, we identify the hot-sensing neurons and show that hot and cold antennal receptors project onto distinct, but adjacent glomeruli in the Proximal-Antennal-Protocerebrum (PAP) form...

  8. Scene-library-based video coding scheme exploiting long-term temporal correlation

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    Zuo, Xuguang; Yu, Lu; Yu, Hualong; Mao, Jue; Zhao, Yin

    2017-07-01

    In movies and TV shows, it is common that several scenes repeat alternately. These videos are characterized with the long-term temporal correlation, which can be exploited to improve video coding efficiency. However, in applications supporting random access (RA), a video is typically divided into a number of RA segments (RASs) by RA points (RAPs), and different RASs are coded independently. In such a way, the long-term temporal correlation among RASs with similar scenes cannot be used. We present a scene-library-based video coding scheme for the coding of videos with repeated scenes. First, a compact scene library is built by clustering similar scenes and extracting representative frames in encoding video. Then, the video is coded using a layered scene-library-based coding structure, in which the library frames serve as long-term reference frames. The scene library is not cleared by RAPs so that the long-term temporal correlation between RASs from similar scenes can be exploited. Furthermore, the RAP frames are coded as interframes by only referencing library frames so as to improve coding efficiency while maintaining RA property. Experimental results show that the coding scheme can achieve significant coding gain over state-of-the-art methods.

  9. Noninvasive Deep Brain Stimulation via Temporally Interfering Electric Fields

    OpenAIRE

    Grossman, Nir; De Bono, David; Dedic, Nina; Kodandaramaiah, Suhasa B.; Rudenko, Andrii; Suk, Ho-Jun; Cassara, Antonio M.; Neufeld, Esra; Kuster, Niels; Tsai, Li-Huei; Pascual-Leone, Alvaro; Boyden, Edward S.

    2017-01-01

    We report a noninvasive strategy for electrically stimulating neurons at depth. By delivering to the brain multiple electric fields at frequencies too high to recruit neural firing, but which differ by a frequency within the dynamic range of neural firing, we can electrically stimulate neurons throughout a region where interference between the multiple fields results in a prominent electric field envelope modulated at the difference frequency. We validated this temporal interference (TI) conc...

  10. Temporal perceptual coding using a visual acuity model

    Science.gov (United States)

    Adzic, Velibor; Cohen, Robert A.; Vetro, Anthony

    2014-02-01

    This paper describes research and results in which a visual acuity (VA) model of the human visual system (HVS) is used to reduce the bitrate of coded video sequences, by eliminating the need to signal transform coefficients when their corresponding frequencies will not be detected by the HVS. The VA model is integrated into the state of the art HEVC HM codec. Compared to the unmodified codec, up to 45% bitrate savings are achieved while maintaining the same subjective quality of the video sequences. Encoding times are reduced as well.

  11. A spatio-temporal reference model of the aging brain.

    Science.gov (United States)

    Huizinga, W; Poot, D H J; Vernooij, M W; Roshchupkin, G V; Bron, E E; Ikram, M A; Rueckert, D; Niessen, W J; Klein, S

    2017-12-05

    Both normal aging and neurodegenerative disorders such as Alzheimer's disease (AD) cause morphological changes of the brain. It is generally difficult to distinguish these two causes of morphological change by visual inspection of magnetic resonance (MR) images. To facilitate making this distinction and thus aid the diagnosis of neurodegenerative disorders, we propose a method for developing a spatio-temporal model of morphological differences in the brain due to normal aging. The method utilizes groupwise image registration to characterize morphological variation across brain scans of people with different ages. To extract the deformations that are due to normal aging we use partial least squares regression, which yields modes of deformations highly correlated with age, and corresponding scores for each input subject. Subsequently, we determine a distribution of morphologies as a function of age by fitting smooth percentile curves to these scores. This distribution is used as a reference to which a person's morphology score can be compared. We validate our method on two different datasets, using images from both cognitively normal subjects and patients with Alzheimer disease (AD). Results show that the proposed framework extracts the expected atrophy patterns. Moreover, the morphology scores of cognitively normal subjects are on average lower than the scores of AD subjects, indicating that morphology differences between AD subjects and healthy subjects can be partly explained by accelerated aging. With our methods we are able to assess accelerated brain aging on both population and individual level. A spatio-temporal aging brain model derived from 988 T1-weighted MR brain scans from a large population imaging study (age range 45.9-91.7y, mean age 68.3y) is made publicly available at www.agingbrain.nl. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. The coding of temperature in the Drosophila brain.

    Science.gov (United States)

    Gallio, Marco; Ofstad, Tyler A; Macpherson, Lindsey J; Wang, Jing W; Zuker, Charles S

    2011-02-18

    Thermosensation is an indispensable sensory modality. Here, we study temperature coding in Drosophila, and show that temperature is represented by a spatial map of activity in the brain. First, we identify TRP channels that function in the fly antenna to mediate the detection of cold stimuli. Next, we identify the hot-sensing neurons and show that hot and cold antennal receptors project onto distinct, but adjacent glomeruli in the Proximal-Antennal-Protocerebrum (PAP) forming a thermotopic map in the brain. We use two-photon imaging to reveal the functional segregation of hot and cold responses in the PAP, and show that silencing the hot- or cold-sensing neurons produces animals with distinct and discrete deficits in their behavioral responses to thermal stimuli. Together, these results demonstrate that dedicated populations of cells orchestrate behavioral responses to different temperature stimuli, and reveal a labeled-line logic for the coding of temperature information in the brain. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Imaging structural and functional brain networks in temporal lobe epilepsy

    Science.gov (United States)

    Bernhardt, Boris C.; Hong, SeokJun; Bernasconi, Andrea; Bernasconi, Neda

    2013-01-01

    Early imaging studies in temporal lobe epilepsy (TLE) focused on the search for mesial temporal sclerosis, as its surgical removal results in clinically meaningful improvement in about 70% of patients. Nevertheless, a considerable subgroup of patients continues to suffer from post-operative seizures. Although the reasons for surgical failure are not fully understood, electrophysiological and imaging data suggest that anomalies extending beyond the temporal lobe may have negative impact on outcome. This hypothesis has revived the concept of human epilepsy as a disorder of distributed brain networks. Recent methodological advances in non-invasive neuroimaging have led to quantify structural and functional networks in vivo. While structural networks can be inferred from diffusion MRI tractography and inter-regional covariance patterns of structural measures such as cortical thickness, functional connectivity is generally computed based on statistical dependencies of neurophysiological time-series, measured through functional MRI or electroencephalographic techniques. This review considers the application of advanced analytical methods in structural and functional connectivity analyses in TLE. We will specifically highlight findings from graph-theoretical analysis that allow assessing the topological organization of brain networks. These studies have provided compelling evidence that TLE is a system disorder with profound alterations in local and distributed networks. In addition, there is emerging evidence for the utility of network properties as clinical diagnostic markers. Nowadays, a network perspective is considered to be essential to the understanding of the development, progression, and management of epilepsy. PMID:24098281

  14. Noninvasive Deep Brain Stimulation via Temporally Interfering Electric Fields.

    Science.gov (United States)

    Grossman, Nir; Bono, David; Dedic, Nina; Kodandaramaiah, Suhasa B; Rudenko, Andrii; Suk, Ho-Jun; Cassara, Antonino M; Neufeld, Esra; Kuster, Niels; Tsai, Li-Huei; Pascual-Leone, Alvaro; Boyden, Edward S

    2017-06-01

    We report a noninvasive strategy for electrically stimulating neurons at depth. By delivering to the brain multiple electric fields at frequencies too high to recruit neural firing, but which differ by a frequency within the dynamic range of neural firing, we can electrically stimulate neurons throughout a region where interference between the multiple fields results in a prominent electric field envelope modulated at the difference frequency. We validated this temporal interference (TI) concept via modeling and physics experiments, and verified that neurons in the living mouse brain could follow the electric field envelope. We demonstrate the utility of TI stimulation by stimulating neurons in the hippocampus of living mice without recruiting neurons of the overlying cortex. Finally, we show that by altering the currents delivered to a set of immobile electrodes, we can steerably evoke different motor patterns in living mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Entropy quantification of human brain spatio-temporal dynamics

    Science.gov (United States)

    Pezard, Laurent; Martinerie, Jacques; Müller-Gerking, Johannes; Varela, Francisco J.; Renault, Bernard

    We present a procedure to quantify spatio-temporal dynamics applied here to brain surface recordings during three distinct cognitive tasks. The method uses 19 sites of EEG recording as spatial embedding for the reconstruction of trajectories, global and local linear indices, and non-linear forecasting methods to quantify the global and local information loss of the dynamics (K-entropy). We show that K-entropy can differentiate between raw and multivariate phase random surrogate data in a significant percentage of EEG segments, and that relevant non-linear indices are best studied in time segments not longer than 4s. We also find a certain complementarity between local non-linear and linear indices for the discrimination between the three cognitive tasks. Moreover, localized projections onto electrode site of K-entropy provide a new kind of brain mapping with functional significance.

  16. Temporal event-structure coding in developmental dyslexia: Evidence from explicit and implicit temporal processes

    Directory of Open Access Journals (Sweden)

    Elliott Mark A.

    2010-01-01

    Full Text Available As an alternative to theories positing visual or phonological deficits it has been suggested that the aetiology of dyslexia takes the form of a temporal processing deficit that may refer to impairment in the functional connectivity of the processes involved in reading. Here we investigated this idea in an experimental task designed to measure simultaneity thresholds. Fifteen children diagnosed with developmental dyslexia, alongside a matched sample of 13 normal readers undertook a series of threshold determination procedures designed to locate visual simultaneity thresholds and to assess the influence of subthreshold synchrony or asynchrony upon these thresholds. While there were no significant differences in simultaneity thresholds between dyslexic and normal readers, indicating no evidence of an altered perception, or temporal quantization of events, the dyslexic readers reported simultaneity significantly less frequently than normal readers, with the reduction largely attributable presentation of a subthreshold asynchrony. The results are discussed in terms of a whole systems approach to maintaining information processing integrity.

  17. Bitter taste stimuli induce differential neural codes in mouse brain.

    Directory of Open Access Journals (Sweden)

    David M Wilson

    Full Text Available A growing literature suggests taste stimuli commonly classified as "bitter" induce heterogeneous neural and perceptual responses. Here, the central processing of bitter stimuli was studied in mice with genetically controlled bitter taste profiles. Using these mice removed genetic heterogeneity as a factor influencing gustatory neural codes for bitter stimuli. Electrophysiological activity (spikes was recorded from single neurons in the nucleus tractus solitarius during oral delivery of taste solutions (26 total, including concentration series of the bitter tastants quinine, denatonium benzoate, cycloheximide, and sucrose octaacetate (SOA, presented to the whole mouth for 5 s. Seventy-nine neurons were sampled; in many cases multiple cells (2 to 5 were recorded from a mouse. Results showed bitter stimuli induced variable gustatory activity. For example, although some neurons responded robustly to quinine and cycloheximide, others displayed concentration-dependent activity (p<0.05 to quinine but not cycloheximide. Differential activity to bitter stimuli was observed across multiple neurons recorded from one animal in several mice. Across all cells, quinine and denatonium induced correlated spatial responses that differed (p<0.05 from those to cycloheximide and SOA. Modeling spatiotemporal neural ensemble activity revealed responses to quinine/denatonium and cycloheximide/SOA diverged during only an early, at least 1 s wide period of the taste response. Our findings highlight how temporal features of sensory processing contribute differences among bitter taste codes and build on data suggesting heterogeneity among "bitter" stimuli, data that challenge a strict monoguesia model for the bitter quality.

  18. Temporal code in the vibrissal system-Part II: Roughness surface discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, F D [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, Postal Code CP 4000 (Argentina); AlbarracIn, A L [Catedra de Neurociencias, Facultad de Medicina, Universidad Nacional de Tucuman (Argentina); Felice, C J [Departamento de BioingenierIa, FACET, Universidad Nacional de Tucuman, INSIBIO - CONICET, CC 327, Postal Code CP 4000 (Argentina)

    2007-11-15

    Previous works have purposed hypotheses about the neural code of the tactile system in the rat. One of them is based on the physical characteristics of vibrissae, such as frequency of resonance; another is based on discharge patterns on the trigeminal ganglion. In this work, the purpose is to find a temporal code analyzing the afferent signals of two vibrissal nerves while vibrissae sweep surfaces of different roughness. Two levels of pressure were used between the vibrissa and the contact surface. We analyzed the afferent discharge of DELTA and GAMMA vibrissal nerves. The vibrissae movements were produced using electrical stimulation of the facial nerve. The afferent signals were analyzed using an event detection algorithm based on Continuous Wavelet Transform (CWT). The algorithm was able to detect events of different duration. The inter-event times detected were calculated for each situation and represented in box plot. This work allowed establishing the existence of a temporal code at peripheral level.

  19. Improved Side Information Generation for Distributed Video Coding by Exploiting Spatial and Temporal Correlations

    Directory of Open Access Journals (Sweden)

    Ye Shuiming

    2009-01-01

    Full Text Available Distributed video coding (DVC is a video coding paradigm allowing low complexity encoding for emerging applications such as wireless video surveillance. Side information (SI generation is a key function in the DVC decoder, and plays a key-role in determining the performance of the codec. This paper proposes an improved SI generation for DVC, which exploits both spatial and temporal correlations in the sequences. Partially decoded Wyner-Ziv (WZ frames, based on initial SI by motion compensated temporal interpolation, are exploited to improve the performance of the whole SI generation. More specifically, an enhanced temporal frame interpolation is proposed, including motion vector refinement and smoothing, optimal compensation mode selection, and a new matching criterion for motion estimation. The improved SI technique is also applied to a new hybrid spatial and temporal error concealment scheme to conceal errors in WZ frames. Simulation results show that the proposed scheme can achieve up to 1.0 dB improvement in rate distortion performance in WZ frames for video with high motion, when compared to state-of-the-art DVC. In addition, both the objective and perceptual qualities of the corrupted sequences are significantly improved by the proposed hybrid error concealment scheme, outperforming both spatial and temporal concealments alone.

  20. Spike-coding mechanisms of cerebellar temporal processing in classical conditioning and voluntary movements.

    Science.gov (United States)

    Yamaguchi, Kenji; Sakurai, Yoshio

    2014-10-01

    Time is a fundamental and critical factor in daily life. Millisecond timing, which is the underlying temporal processing for speaking, dancing, and other activities, is reported to rely on the cerebellum. In this review, we discuss the cerebellar spike-coding mechanisms for temporal processing. Although the contribution of the cerebellum to both classical conditioning and voluntary movements is well known, the difference of the mechanisms for temporal processing between classical conditioning and voluntary movements is not clear. Therefore, we review the evidence of cerebellar temporal processing in studies of classical conditioning and voluntary movements and report the similarities and differences between them. From some studies, which used tasks that can change some of the temporal properties (e.g., the duration of interstimulus intervals) with keeping identical movements, we concluded that classical conditioning and voluntary movements may share a common spike-coding mechanism because simple spikes in Purkinje cells decrease at predicted times for responses regardless of the intervals between responses or stimulation.

  1. Efficient temporal and interlayer parameter prediction for weighted prediction in scalable high efficiency video coding

    Science.gov (United States)

    Tsang, Sik-Ho; Chan, Yui-Lam; Siu, Wan-Chi

    2017-01-01

    Weighted prediction (WP) is an efficient video coding tool that was introduced since the establishment of the H.264/AVC video coding standard, for compensating the temporal illumination change in motion estimation and compensation. WP parameters, including a multiplicative weight and an additive offset for each reference frame, are required to be estimated and transmitted to the decoder by slice header. These parameters cause extra bits in the coded video bitstream. High efficiency video coding (HEVC) provides WP parameter prediction to reduce the overhead. Therefore, WP parameter prediction is crucial to research works or applications, which are related to WP. Prior art has been suggested to further improve the WP parameter prediction by implicit prediction of image characteristics and derivation of parameters. By exploiting both temporal and interlayer redundancies, we propose three WP parameter prediction algorithms, enhanced implicit WP parameter, enhanced direct WP parameter derivation, and interlayer WP parameter, to further improve the coding efficiency of HEVC. Results show that our proposed algorithms can achieve up to 5.83% and 5.23% bitrate reduction compared to the conventional scalable HEVC in the base layer for SNR scalability and 2× spatial scalability, respectively.

  2. Laminar and Temporal Expression Dynamics of Coding and Noncoding RNAs in the Mouse Neocortex

    Directory of Open Access Journals (Sweden)

    Sofia Fertuzinhos

    2014-03-01

    Full Text Available The hallmark of the cerebral neocortex is its organization into six layers, each containing a characteristic set of cell types and synaptic connections. The transcriptional events involved in laminar development and function still remain elusive. Here, we employed deep sequencing of mRNA and small RNA species to gain insights into transcriptional differences among layers and their temporal dynamics during postnatal development of the mouse primary somatosensory neocortex. We identify a number of coding and noncoding transcripts with specific spatiotemporal expression and splicing patterns. We also identify signature trajectories and gene coexpression networks associated with distinct biological processes and transcriptional overlap between these processes. Finally, we provide data that allow the study of potential miRNA and mRNA interactions. Overall, this study provides an integrated view of the laminar and temporal expression dynamics of coding and noncoding transcripts in the mouse neocortex and a resource for studies of neurodevelopment and transcriptome.

  3. Distorted Tonotopic Coding of Temporal Envelope and Fine Structure with Noise-Induced Hearing Loss.

    Science.gov (United States)

    Henry, Kenneth S; Kale, Sushrut; Heinz, Michael G

    2016-02-17

    People with cochlear hearing loss have substantial difficulty understanding speech in real-world listening environments (e.g., restaurants), even with amplification from a modern digital hearing aid. Unfortunately, a disconnect remains between human perceptual studies implicating diminished sensitivity to fast acoustic temporal fine structure (TFS) and animal studies showing minimal changes in neural coding of TFS or slower envelope (ENV) structure. Here, we used general system-identification (Wiener kernel) analyses of chinchilla auditory nerve fiber responses to Gaussian noise to reveal pronounced distortions in tonotopic coding of TFS and ENV following permanent, noise-induced hearing loss. In basal fibers with characteristic frequencies (CFs) >1.5 kHz, hearing loss introduced robust nontonotopic coding (i.e., at the wrong cochlear place) of low-frequency TFS, while ENV responses typically remained at CF. As a consequence, the highest dominant frequency of TFS coding in response to Gaussian noise was 2.4 kHz in noise-overexposed fibers compared with 4.5 kHz in control fibers. Coding of ENV also became nontonotopic in more pronounced cases of cochlear damage. In apical fibers, more classical hearing-loss effects were observed, i.e., broadened tuning without a significant shift in best frequency. Because these distortions and dissociations of TFS/ENV disrupt tonotopicity, a fundamental principle of auditory processing necessary for robust signal coding in background noise, these results have important implications for understanding communication difficulties faced by people with hearing loss. Further, hearing aids may benefit from distinct amplification strategies for apical and basal cochlear regions to address fundamentally different coding deficits. Speech-perception problems associated with noise overexposure are pervasive in today's society, even with modern digital hearing aids. Unfortunately, the underlying physiological deficits in neural coding remain

  4. Distorted Tonotopic Coding of Temporal Envelope and Fine Structure with Noise-Induced Hearing Loss

    OpenAIRE

    Henry, Kenneth S; Kale, Sushrut; Heinz, Michael G.

    2016-01-01

    People with cochlear hearing loss have substantial difficulty understanding speech in real-world listening environments (e.g., restaurants), even with amplification from a modern digital hearing aid. Unfortunately, a disconnect remains between human perceptual studies implicating diminished sensitivity to fast acoustic temporal fine structure (TFS) and animal studies showing minimal changes in neural coding of TFS or slower envelope (ENV) structure. Here, we used general system-identification...

  5. Relation between temporal envelope coding, pitch discrimination, and compression estimates in listeners with sensorineural hearing loss

    DEFF Research Database (Denmark)

    Bianchi, Federica; Santurette, Sébastien; Fereczkowski, Michal

    2015-01-01

    Recent physiological studies in animals showed that noise-induced sensorineural hearing loss (SNHL) increased the amplitude of envelope coding in single auditory-nerve fibers. The present study investigated whether SNHL in human listeners was associated with enhanced temporal envelope coding...... resolvability. For the unresolved conditions, all five HI listeners performed as good as or better than NH listeners with matching musical experience. Two HI listeners showed lower amplitude-modulation detection thresholds than NH listeners for low modulation rates, and one of these listeners also showed a loss......, whether this enhancement affected pitch discrimination performance, and whether loss of compression following SNHL was a potential factor in envelope coding enhancement. Envelope processing was assessed in normal-hearing (NH) and hearing-impaired (HI) listeners in a behavioral amplitude...

  6. Spatial and temporal codes mediate the tactile perception of natural textures.

    Science.gov (United States)

    Weber, Alison I; Saal, Hannes P; Lieber, Justin D; Cheng, Ju-Wen; Manfredi, Louise R; Dammann, John F; Bensmaia, Sliman J

    2013-10-15

    When we run our fingers over the surface of an object, we acquire information about its microgeometry and material properties. Texture information is widely believed to be conveyed in spatial patterns of activation evoked across one of three populations of cutaneous mechanoreceptive afferents that innervate the fingertips. Here, we record the responses evoked in individual cutaneous afferents in Rhesus macaques as we scan a diverse set of natural textures across their fingertips using a custom-made rotating drum stimulator. We show that a spatial mechanism can only account for the processing of coarse textures. Information about most natural textures, however, is conveyed through precise temporal spiking patterns in afferent responses, driven by high-frequency skin vibrations elicited during scanning. Furthermore, these texture-specific spiking patterns predictably dilate or contract in time with changes in scanning speed; the systematic effect of speed on neuronal activity suggests that it can be reversed to achieve perceptual constancy across speeds. The proposed temporal coding mechanism involves converting the fine spatial structure of the surface into a temporal spiking pattern, shaped in part by the mechanical properties of the skin, and ascribes an additional function to vibration-sensitive mechanoreceptive afferents. This temporal mechanism complements the spatial one and greatly extends the range of tangible textures. We show that a combination of spatial and temporal mechanisms, mediated by all three populations of afferents, accounts for perceptual judgments of texture.

  7. Temporal Code-Driven Stimulation: Definition and Application to Electric Fish Signaling

    Science.gov (United States)

    Lareo, Angel; Forlim, Caroline G.; Pinto, Reynaldo D.; Varona, Pablo; Rodriguez, Francisco de Borja

    2016-01-01

    Closed-loop activity-dependent stimulation is a powerful methodology to assess information processing in biological systems. In this context, the development of novel protocols, their implementation in bioinformatics toolboxes and their application to different description levels open up a wide range of possibilities in the study of biological systems. We developed a methodology for studying biological signals representing them as temporal sequences of binary events. A specific sequence of these events (code) is chosen to deliver a predefined stimulation in a closed-loop manner. The response to this code-driven stimulation can be used to characterize the system. This methodology was implemented in a real time toolbox and tested in the context of electric fish signaling. We show that while there are codes that evoke a response that cannot be distinguished from a control recording without stimulation, other codes evoke a characteristic distinct response. We also compare the code-driven response to open-loop stimulation. The discussed experiments validate the proposed methodology and the software toolbox. PMID:27766078

  8. Noise-induced hearing loss increases the temporal precision of complex envelope coding by auditory-nerve fibers

    Directory of Open Access Journals (Sweden)

    Kenneth Stuart Henry

    2014-02-01

    Full Text Available While changes in cochlear frequency tuning are thought to play an important role in the perceptual difficulties of people with sensorineural hearing loss (SNHL, the possible role of temporal processing deficits remains less clear. Our knowledge of temporal envelope coding in the impaired cochlea is limited to two studies that examined auditory-nerve fiber responses to narrowband amplitude modulated stimuli. In the present study, we used Wiener-kernel analyses of auditory-nerve fiber responses to broadband Gaussian noise in anesthetized chinchillas to quantify changes in temporal envelope coding with noise-induced SNHL. Temporal modulation transfer functions (TMTFs and temporal windows of sensitivity to acoustic stimulation were computed from 2nd-order Wiener kernels and analyzed to estimate the temporal precision, amplitude, and latency of envelope coding. Noise overexposure was associated with slower (less negative TMTF roll-off with increasing modulation frequency and reduced temporal window duration. The results show that at equal stimulus sensation level, SNHL increases the temporal precision of envelope coding by 20-30%. Furthermore, SNHL increased the amplitude of envelope coding by 50% in fibers with CFs from 1-2 kHz and decreased mean response latency by 0.4 ms. While a previous study of envelope coding demonstrated a similar increase in response amplitude, the present study is the first to show enhanced temporal precision. This new finding may relate to the use of a more complex stimulus with broad frequency bandwidth and a dynamic temporal envelope. Exaggerated neural coding of fast envelope modulations may contribute to perceptual difficulties in people with SNHL by acting as a distraction from more relevant acoustic cues, especially in fluctuating background noise. Finally, the results underscore the value of studying sensory systems with more natural, real-world stimuli.

  9. Binary temporal upconversion codes of Mn2+-activated nanoparticles for multilevel anti-counterfeiting.

    Science.gov (United States)

    Liu, Xiaowang; Wang, Yu; Li, Xiyan; Yi, Zhigao; Deng, Renren; Liang, Liangliang; Xie, Xiaoji; Loong, Daniel T B; Song, Shuyan; Fan, Dianyuan; All, Angelo H; Zhang, Hongjie; Huang, Ling; Liu, Xiaogang

    2017-10-12

    Optical characteristics of luminescent materials, such as emission profile and lifetime, play an important role in their applications in optical data storage, document security, diagnostics, and therapeutics. Lanthanide-doped upconversion nanoparticles are particularly suitable for such applications due to their inherent optical properties, including large anti-Stokes shift, distinguishable spectroscopic fingerprint, and long luminescence lifetime. However, conventional upconversion nanoparticles have a limited capacity for information storage or complexity to prevent counterfeiting. Here, we demonstrate that integration of long-lived Mn2+ upconversion emission and relatively short-lived lanthanide upconversion emission in a particulate platform allows the generation of binary temporal codes for efficient data encoding. Precise control of the particle's structure allows the excitation feasible both under 980 and 808 nm irradiation. We find that the as-prepared Mn2+-doped nanoparticles are especially useful for multilevel anti-counterfeiting with high-throughput rate of authentication and without the need for complex time-gated decoding instrumentation.Luminescent materials that are capable of binary temporal coding are desirable for multilevel anti-counterfeiting. Here, the authors engineer nanoparticles that produce binary color codes on different timescales by combining the long-lived luminescence of Mn2+ with the relatively short-lived emission of lanthanides.

  10. Imaging structural and functional brain networks in temporal lobe epilepsy

    National Research Council Canada - National Science Library

    Bernhardt, Boris C; Hong, Seokjun; Bernasconi, Andrea; Bernasconi, Neda

    2013-01-01

    Early imaging studies in temporal lobe epilepsy (TLE) focused on the search for mesial temporal sclerosis, as its surgical removal results in clinically meaningful improvement in about 70% of patients...

  11. Model-Based Speech Signal Coding Using Optimized Temporal Decomposition for Storage and Broadcasting Applications

    Science.gov (United States)

    Athaudage, Chandranath R. N.; Bradley, Alan B.; Lech, Margaret

    2003-12-01

    A dynamic programming-based optimization strategy for a temporal decomposition (TD) model of speech and its application to low-rate speech coding in storage and broadcasting is presented. In previous work with the spectral stability-based event localizing (SBEL) TD algorithm, the event localization was performed based on a spectral stability criterion. Although this approach gave reasonably good results, there was no assurance on the optimality of the event locations. In the present work, we have optimized the event localizing task using a dynamic programming-based optimization strategy. Simulation results show that an improved TD model accuracy can be achieved. A methodology of incorporating the optimized TD algorithm within the standard MELP speech coder for the efficient compression of speech spectral information is also presented. The performance evaluation results revealed that the proposed speech coding scheme achieves 50%-60% compression of speech spectral information with negligible degradation in the decoded speech quality.

  12. Chronic deep brain stimulation in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Boëx, Colette; Seeck, Margitta; Vulliémoz, Serge; Rossetti, Andrea O; Staedler, Claudio; Spinelli, Laurent; Pegna, Alan J; Pralong, Etienne; Villemure, Jean-Guy; Foletti, Giovanni; Pollo, Claudio

    2011-07-01

    The objective of this study was to evaluate the efficiency and the effects of changes in parameters of chronic amygdala-hippocampal deep brain stimulation (AH-DBS) in mesial temporal lobe epilepsy (TLE). Eight pharmacoresistant patients, not candidates for ablative surgery, received chronic AH-DBS (130 Hz, follow-up 12-24 months): two patients with hippocampal sclerosis (HS) and six patients with non-lesional mesial TLE (NLES). The effects of stepwise increases in intensity (0-Off to 2 V) and stimulation configuration (quadripolar and bipolar), on seizure frequency and neuropsychological performance were studied. The two HS patients obtained a significant decrease (65-75%) in seizure frequency with high voltage bipolar DBS (≥1 V) or with quadripolar stimulation. Two out of six NLES patients became seizure-free, one of them without stimulation, suggesting a microlesional effect. Two NLES patients experienced reductions of seizure frequency (65-70%), whereas the remaining two showed no significant seizure reduction. Neuropsychological evaluations showed reversible memory impairments in two patients under strong stimulation only. AH-DBS showed long-term efficiency in most of the TLE patients. It is a valuable treatment option for patients who suffer from drug resistant epilepsy and who are not candidates for resective surgery. The effects of changes in the stimulation parameters suggest that a large zone of stimulation would be required in HS patients, while a limited zone of stimulation or even a microlesional effect could be sufficient in NLES patients, for whom the importance of the proximity of the electrode to the epileptogenic zone remains to be studied. Further studies are required to ascertain these latter observations. Copyright © 2011 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  13. Temporal trends in the systemic inflammatory response syndrome, sepsis, and medical coding of sepsis.

    Science.gov (United States)

    Thomas, Benjamin S; Jafarzadeh, S Reza; Warren, David K; McCormick, Sandra; Fraser, Victoria J; Marschall, Jonas

    2015-11-24

    Recent reports using administrative claims data suggest the incidence of community- and hospital-onset sepsis is increasing. Whether this reflects changing epidemiology, more effective diagnostic methods, or changes in physician documentation and medical coding practices is unclear. We performed a temporal-trend study from 2008 to 2012 using administrative claims data and patient-level clinical data of adult patients admitted to Barnes-Jewish Hospital in St. Louis, Missouri. Temporal-trend and annual percent change were estimated using regression models with autoregressive integrated moving average errors. We analyzed 62,261 inpatient admissions during the 5-year study period. 'Any SIRS' (i.e., SIRS on a single calendar day during the hospitalization) and 'multi-day SIRS' (i.e., SIRS on 3 or more calendar days), which both use patient-level data, and medical coding for sepsis (i.e., ICD-9-CM discharge diagnosis codes 995.91, 995.92, or 785.52) were present in 35.3 %, 17.3 %, and 3.3 % of admissions, respectively. The incidence of admissions coded for sepsis increased 9.7 % (95 % CI: 6.1, 13.4) per year, while the patient data-defined events of 'any SIRS' decreased by 1.8 % (95 % CI: -3.2, -0.5) and 'multi-day SIRS' did not change significantly over the study period. Clinically-defined sepsis (defined as SIRS plus bacteremia) and severe sepsis (defined as SIRS plus hypotension and bacteremia) decreased at statistically significant rates of 5.7 % (95 % CI: -9.0, -2.4) and 8.6 % (95 % CI: -4.4, -12.6) annually. All-cause mortality, SIRS mortality, and SIRS and clinically-defined sepsis case fatality did not change significantly during the study period. Sepsis mortality, based on ICD-9-CM codes, however, increased by 8.8 % (95 % CI: 1.9, 16.2) annually. The incidence of sepsis, defined by ICD-9-CM codes, and sepsis mortality increased steadily without a concomitant increase in SIRS or clinically-defined sepsis. Our results highlight the need to develop

  14. NIH Scientists Try to Crack the Brain's Memory Codes

    Science.gov (United States)

    ... they were shown. Electrical recordings showed that the brain waves the patients experienced when they correctly stored and ... when recalling the words happened faster than the waves that were present when ... suggest the brain replays memories on fast forward,” said Dr. Zaghloul. ...

  15. Models of neural networks temporal aspects of coding and information processing in biological systems

    CERN Document Server

    Hemmen, J; Schulten, Klaus

    1994-01-01

    Since the appearance of Vol. 1 of Models of Neural Networks in 1991, the theory of neural nets has focused on two paradigms: information coding through coherent firing of the neurons and functional feedback. Information coding through coherent neuronal firing exploits time as a cardinal degree of freedom. This capacity of a neural network rests on the fact that the neuronal action potential is a short, say 1 ms, spike, localized in space and time. Spatial as well as temporal correlations of activity may represent different states of a network. In particular, temporal correlations of activity may express that neurons process the same "object" of, for example, a visual scene by spiking at the very same time. The traditional description of a neural network through a firing rate, the famous S-shaped curve, presupposes a wide time window of, say, at least 100 ms. It thus fails to exploit the capacity to "bind" sets of coherently firing neurons for the purpose of both scene segmentation and figure-ground segregatio...

  16. Non-contact assessment of melanin distribution via multispectral temporal illumination coding

    Science.gov (United States)

    Amelard, Robert; Scharfenberger, Christian; Wong, Alexander; Clausi, David A.

    2015-03-01

    Melanin is a pigment that is highly absorptive in the UV and visible electromagnetic spectra. It is responsible for perceived skin tone, and protects against harmful UV effects. Abnormal melanin distribution is often an indicator for melanoma. We propose a novel approach for non-contact melanin distribution via multispectral temporal illumination coding to estimate the two-dimensional melanin distribution based on its absorptive characteristics. In the proposed system, a novel multispectral, cross-polarized, temporally-coded illumination sequence is synchronized with a camera to measure reflectance under both multispectral and ambient illumination. This allows us to eliminate the ambient illumination contribution from the acquired reflectance measurements, and also to determine the melanin distribution in an observed region based on the spectral properties of melanin using the Beer-Lambert law. Using this information, melanin distribution maps can be generated for objective, quantitative assessment of skin type of individuals. We show that the melanin distribution map correctly identifies areas with high melanin densities (e.g., nevi).

  17. Analysis of spatial-temporal gene expression patterns reveals dynamics and regionalization in developing mouse brain

    OpenAIRE

    Shen-Ju Chou; Chindi Wang; Nardnisa Sintupisut; Zhen-Xian Niou; Chih-Hsu Lin; Ker-Chau Li; Chen-Hsiang Yeang

    2016-01-01

    Allen Brain Atlas (ABA) provides a valuable resource of spatial/temporal gene expressions in mammalian brains. Despite rich information extracted from this database, current analyses suffer from several limitations. First, most studies are either gene-centric or region-centric, thus are inadequate to capture the superposition of multiple spatial-temporal patterns. Second, standard tools of expression analysis such as matrix factorization can capture those patterns but do not explicitly incorp...

  18. Octopaminergic modulation of temporal frequency coding in an identified optic flow-processing interneuron

    Directory of Open Access Journals (Sweden)

    Kit D. Longden

    2010-11-01

    Full Text Available Flying generates predictably different patterns of optic flow compared with other locomotor states. A sensorimotor system tuned to rapid responses and a high bandwidth of optic flow would help the animal to avoid wasting energy through imprecise motor action. However, neural processing that covers a higher input bandwidth itself comes at higher energetic costs which would be a poor investment when the animal was not flying. How does the blowfly adjust the dynamic range of its optic flow-processing neurons to the locomotor state? Octopamine (OA is a biogenic amine central to the initiation and maintenance of flight in insects. We used an OA agonist chlordimeform (CDM to simulate the widespread OA release during flight and recorded the effects on the temporal frequency coding of the H2 cell. This cell is a visual interneuron known to be involved in flight stabilization reflexes. The application of CDM resulted in i an increase in the cell's spontaneous activity, expanding the inhibitory signalling range ii an initial response gain to moving gratings (20 – 60 ms post-stimulus that depended on the temporal frequency of the grating and iii a reduction in the rate and magnitude of motion adaptation that was also temporal frequency-dependent. To our knowledge, this is the first demonstration that the application of a neuromodulator can induce velocity-dependent alterations in the gain of a wide-field optic flow-processing neuron. The observed changes in the cell’s response properties resulted in a 33% increase of the cell’s information rate when encoding random changes in temporal frequency of the stimulus. The increased signalling range and more rapid, longer lasting responses employed more spikes to encode each bit, and so consumed a greater amount of energy. It appears that for the fly investing more energy in sensory processing during flight is more efficient than wasting energy on under-performing motor control.

  19. Slow Temporal Integration Enables Robust Neural Coding and Perception of a Cue to Sound Source Location.

    Science.gov (United States)

    Brown, Andrew D; Tollin, Daniel J

    2016-09-21

    In mammals, localization of sound sources in azimuth depends on sensitivity to interaural differences in sound timing (ITD) and level (ILD). Paradoxically, while typical ILD-sensitive neurons of the auditory brainstem require millisecond synchrony of excitatory and inhibitory inputs for the encoding of ILDs, human and animal behavioral ILD sensitivity is robust to temporal stimulus degradations (e.g., interaural decorrelation due to reverberation), or, in humans, bilateral clinical device processing. Here we demonstrate that behavioral ILD sensitivity is only modestly degraded with even complete decorrelation of left- and right-ear signals, suggesting the existence of a highly integrative ILD-coding mechanism. Correspondingly, we find that a majority of auditory midbrain neurons in the central nucleus of the inferior colliculus (of chinchilla) effectively encode ILDs despite complete decorrelation of left- and right-ear signals. We show that such responses can be accounted for by relatively long windows of bilateral excitatory-inhibitory interaction, which we explicitly measure using trains of narrowband clicks. Neural and behavioral data are compared with the outputs of a simple model of ILD processing with a single free parameter, the duration of excitatory-inhibitory interaction. Behavioral, neural, and modeling data collectively suggest that ILD sensitivity depends on binaural integration of excitation and inhibition within a ≳3 ms temporal window, significantly longer than observed in lower brainstem neurons. This relatively slow integration potentiates a unique role for the ILD system in spatial hearing that may be of particular importance when informative ITD cues are unavailable. In mammalian hearing, interaural differences in the timing (ITD) and level (ILD) of impinging sounds carry critical information about source location. However, natural sounds are often decorrelated between the ears by reverberation and background noise, degrading the fidelity of

  20. Sparse coding reveals greater functional connectivity in female brains during naturalistic emotional experience.

    Directory of Open Access Journals (Sweden)

    Yudan Ren

    Full Text Available Functional neuroimaging is widely used to examine changes in brain function associated with age, gender or neuropsychiatric conditions. FMRI (functional magnetic resonance imaging studies employ either laboratory-designed tasks that engage the brain with abstracted and repeated stimuli, or resting state paradigms with little behavioral constraint. Recently, novel neuroimaging paradigms using naturalistic stimuli are gaining increasing attraction, as they offer an ecologically-valid condition to approximate brain function in real life. Wider application of naturalistic paradigms in exploring individual differences in brain function, however, awaits further advances in statistical methods for modeling dynamic and complex dataset. Here, we developed a novel data-driven strategy that employs group sparse representation to assess gender differences in brain responses during naturalistic emotional experience. Comparing to independent component analysis (ICA, sparse coding algorithm considers the intrinsic sparsity of neural coding and thus could be more suitable in modeling dynamic whole-brain fMRI signals. An online dictionary learning and sparse coding algorithm was applied to the aggregated fMRI signals from both groups, which was subsequently factorized into a common time series signal dictionary matrix and the associated weight coefficient matrix. Our results demonstrate that group sparse representation can effectively identify gender differences in functional brain network during natural viewing, with improved sensitivity and reliability over ICA-based method. Group sparse representation hence offers a superior data-driven strategy for examining brain function during naturalistic conditions, with great potential for clinical application in neuropsychiatric disorders.

  1. Brain networks of temporal preparation: A multiple regression analysis of neuropsychological data.

    Science.gov (United States)

    Triviño, Mónica; Correa, Ángel; Lupiáñez, Juan; Funes, María Jesús; Catena, Andrés; He, Xun; Humphreys, Glyn W

    2016-11-15

    There are only a few studies on the brain networks involved in the ability to prepare in time, and most of them followed a correlational rather than a neuropsychological approach. The present neuropsychological study performed multiple regression analysis to address the relationship between both grey and white matter (measured by magnetic resonance imaging in patients with brain lesion) and different effects in temporal preparation (Temporal orienting, Foreperiod and Sequential effects). Two versions of a temporal preparation task were administered to a group of 23 patients with acquired brain injury. In one task, the cue presented (a red versus green square) to inform participants about the time of appearance (early versus late) of a target stimulus was blocked, while in the other task the cue was manipulated on a trial-by-trial basis. The duration of the cue-target time intervals (400 versus 1400ms) was always manipulated within blocks in both tasks. Regression analysis were conducted between either the grey matter lesion size or the white matter tracts disconnection and the three temporal preparation effects separately. The main finding was that each temporal preparation effect was predicted by a different network of structures, depending on cue expectancy. Specifically, the Temporal orienting effect was related to both prefrontal and temporal brain areas. The Foreperiod effect was related to right and left prefrontal structures. Sequential effects were predicted by both parietal cortex and left subcortical structures. These findings show a clear dissociation of brain circuits involved in the different ways to prepare in time, showing for the first time the involvement of temporal areas in the Temporal orienting effect, as well as the parietal cortex in the Sequential effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Spatio-temporal modeling of connectome-scale brain network interactions via time-evolving graphs.

    Science.gov (United States)

    Yuan, Jing; Li, Xiang; Zhang, Jinhe; Luo, Liao; Dong, Qinglin; Lv, Jinglei; Zhao, Yu; Jiang, Xi; Zhang, Shu; Zhang, Wei; Liu, Tianming

    2017-11-09

    Many recent literature studies have revealed interesting dynamics patterns of functional brain networks derived from fMRI data. However, it has been rarely explored how functional networks spatially overlap (or interact) and how such connectome-scale network interactions temporally evolve. To explore these unanswered questions, this paper presents a novel framework for spatio-temporal modeling of connectome-scale functional brain network interactions via two main effective computational methodologies. First, to integrate, pool and compare brain networks across individuals and their cognitive states under task performances, we designed a novel group-wise dictionary learning scheme to derive connectome-scale consistent brain network templates that can be used to define the common reference space of brain network interactions. Second, the temporal dynamics of spatial network interactions is modeled by a weighted time-evolving graph, and then a data-driven unsupervised learning algorithm based on the dynamic behavioral mixed-membership model (DBMM) is adopted to identify behavioral patterns of brain networks during the temporal evolution process of spatial overlaps/interactions. Experimental results on the Human Connectome Project (HCP) task fMRI data showed that our methods can reveal meaningful, diverse behavior patterns of connectome-scale network interactions. In particular, those networks' behavior patterns are distinct across HCP tasks such as motor, working memory, language and social tasks, and their dynamics well correspond to the temporal changes of specific task designs. In general, our framework offers a new approach to characterizing human brain function by quantitative description for the temporal evolution of spatial overlaps/interactions of connectome-scale brain networks in a standard reference space. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. MAP-MRF-Based Super-Resolution Reconstruction Approach for Coded Aperture Compressive Temporal Imaging

    Directory of Open Access Journals (Sweden)

    Tinghua Zhang

    2018-02-01

    Full Text Available Coded Aperture Compressive Temporal Imaging (CACTI can afford low-cost temporal super-resolution (SR, but limits are imposed by noise and compression ratio on reconstruction quality. To utilize inter-frame redundant information from multiple observations and sparsity in multi-transform domains, a robust reconstruction approach based on maximum a posteriori probability and Markov random field (MAP-MRF model for CACTI is proposed. The proposed approach adopts a weighted 3D neighbor system (WNS and the coordinate descent method to perform joint estimation of model parameters, to achieve the robust super-resolution reconstruction. The proposed multi-reconstruction algorithm considers both total variation (TV and ℓ 2 , 1 norm in wavelet domain to address the minimization problem for compressive sensing, and solves it using an accelerated generalized alternating projection algorithm. The weighting coefficient for different regularizations and frames is resolved by the motion characteristics of pixels. The proposed approach can provide high visual quality in the foreground and background of a scene simultaneously and enhance the fidelity of the reconstruction results. Simulation results have verified the efficacy of our new optimization framework and the proposed reconstruction approach.

  4. Temporal dysfunction in traumatic brain injury patients: Primary or secondary impairment?

    Directory of Open Access Journals (Sweden)

    Giovanna eMioni

    2014-04-01

    Full Text Available Adequate temporal abilities are required for most daily activities. Traumatic brain injury (TBI patients often present with cognitive dysfunctions, but few studies have investigated temporal impairments associated with TBI. The aim of the present work is to review the existing literature on temporal abilities in TBI patients. Particular attention is given to the involvement of higher cognitive processes in temporal processing in order to determine if any temporal dysfunction observed in TBI patients is due to the disruption of an internal clock or to the dysfunction of general cognitive processes. The results showed that temporal dysfunctions in TBI patients are related to the deficits in cognitive functions involved in temporal processing rather than to a specific impairment of the internal clock. In fact, temporal dysfunctions are observed when the length of temporal intervals exceeds the working memory span or when the temporal tasks require high cognitive functions to be performed. The consistent higher temporal variability observed in TBI patients is a sign of impaired frontally mediated cognitive functions involved in time perception.

  5. Analysis of spatial-temporal gene expression patterns reveals dynamics and regionalization in developing mouse brain.

    Science.gov (United States)

    Chou, Shen-Ju; Wang, Chindi; Sintupisut, Nardnisa; Niou, Zhen-Xian; Lin, Chih-Hsu; Li, Ker-Chau; Yeang, Chen-Hsiang

    2016-01-20

    Allen Brain Atlas (ABA) provides a valuable resource of spatial/temporal gene expressions in mammalian brains. Despite rich information extracted from this database, current analyses suffer from several limitations. First, most studies are either gene-centric or region-centric, thus are inadequate to capture the superposition of multiple spatial-temporal patterns. Second, standard tools of expression analysis such as matrix factorization can capture those patterns but do not explicitly incorporate spatial dependency. To overcome those limitations, we proposed a computational method to detect recurrent patterns in the spatial-temporal gene expression data of developing mouse brains. We demonstrated that regional distinction in brain development could be revealed by localized gene expression patterns. The patterns expressed in the forebrain, medullary and pontomedullary, and basal ganglia are enriched with genes involved in forebrain development, locomotory behavior, and dopamine metabolism respectively. In addition, the timing of global gene expression patterns reflects the general trends of molecular events in mouse brain development. Furthermore, we validated functional implications of the inferred patterns by showing genes sharing similar spatial-temporal expression patterns with Lhx2 exhibited differential expression in the embryonic forebrains of Lhx2 mutant mice. These analysis outcomes confirm the utility of recurrent expression patterns in studying brain development.

  6. Determinants of brain metabolism changes in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Chassoux, Francine; Artiges, Eric; Semah, Franck; Desarnaud, Serge; Laurent, Agathe; Landre, Elisabeth; Gervais, Philippe; Devaux, Bertrand; Helal, Ourkia Badia

    2016-06-01

    To determine the main factors influencing metabolic changes in mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis (HS). We prospectively studied 114 patients with MTLE (62 female; 60 left HS; 15- to 56-year-olds) with (18) F-fluorodeoxyglucose-positron emission tomography and correlated the results with the side of HS, structural atrophy, electroclinical features, gender, age at onset, epilepsy duration, and seizure frequency. Imaging processing was performed using statistical parametric mapping. Ipsilateral hypometabolism involved temporal (mesial structures, pole, and lateral cortex) and extratemporal areas including the insula, frontal lobe, perisylvian regions, and thalamus, more extensively in right HS (RHS). A relative increase of metabolism (hypermetabolism) was found in the nonepileptic temporal lobe and in posterior areas bilaterally. Voxel-based morphometry detected unilateral hippocampus atrophy and gray matter concentration decrease in both frontal lobes, more extensively in left HS (LHS). Regardless of the structural alterations, the topography of hypometabolism correlated strongly with the extent of epileptic networks (mesial, anterior-mesiolateral, widespread mesiolateral, and bitemporal according to the ictal spread), which were larger in RHS. Notably, widespread perisylvian and bitemporal hypometabolism was found only in RHS. Mirror hypermetabolism was grossly proportional to the hypometabolic areas, coinciding partly with the default mode network. Gender-related effect was significant mainly in the contralateral frontal lobe, in which metabolism was higher in female patients. Epilepsy duration correlated with the contralateral temporal metabolism, positively in LHS and negatively in RHS. Opposite results were found with age at onset. High seizure frequency correlated negatively with the contralateral metabolism in LHS. Epileptic networks, as assessed by electroclinical correlations, appear to be the main determinant of

  7. Sparse Spatio-temporal Inference of Electromagnetic Brain Sources

    DEFF Research Database (Denmark)

    Stahlhut, Carsten; Attias, Hagai Thomas; Wipf, David

    2010-01-01

    The electromagnetic brain activity measured via MEG (or EEG) can be interpreted as arising from a collection of current dipoles or sources located throughout the cortex. Because the number of candidate locations for these sources is much larger than the number of sensors, source reconstruction...... involves solving an inverse problem that is severely underdetermined. Bayesian graphical models provide a powerful means of incorporating prior assumptions that narrow the solution space and lead to tractable posterior distributions over the unknown sources given the observed data. In particular......-suited for estimation problems that arise from other brain imaging modalities such as functional or diffusion weighted MRI....

  8. Spatio-temporal reconstruction of brain dynamics from EEG with a Markov prior

    DEFF Research Database (Denmark)

    Hansen, Sofie Therese; Hansen, Lars Kai

    2016-01-01

    . We summarize these insights in an inverse solver, the so-called "Variational Garrote" (Kappen and Gómez, 2013). Using a Markov prior we can incorporate flexible degrees of temporal stationarity. Through spatial basis functions spatially smooth distributions are obtained. Sparsity...... of these are inherent to the Variational Garrote solver. We name our method the MarkoVG and demonstrate its ability to adapt to the temporal smoothness and spatial sparsity in simulated EEG data. Finally a benchmark EEG dataset is used to demonstrate MarkoVG's ability to recover non-stationary brain dynamics.......Electroencephalography (EEG) can capture brain dynamics in high temporal resolution. By projecting the scalp EEG signal back to its origin in the brain also high spatial resolution can be achieved. Source localized EEG therefore has potential to be a very powerful tool for understanding...

  9. Decoding Temporal Structure in Music and Speech Relies on Shared Brain Resources but Elicits Different Fine-Scale Spatial Patterns

    National Research Council Canada - National Science Library

    Abrams, Daniel A; Bhatara, Anjali; Ryali, Srikanth; Balaban, Evan; Levitin, Daniel J; Menon, Vinod

    2011-01-01

    .... Although the same manipulation of temporal structure elicited brain activation level differences of similar magnitude for both music and speech stimuli, multivariate classification analysis revealed...

  10. Different brain circuits underlie motor and perceptual representations of temporal intervals

    DEFF Research Database (Denmark)

    Bueti, Doemnica; Walsh, Vincent; Frith, Christopher

    2008-01-01

    mechanisms. However, only in the reproduction task was activity observed in a wider cortical network including the right pre- SMA, left middle frontal gyrus, left premotor cortex, with a more reliable activity in the right inferior parietal cortex, left fusiform gyrus, and the right extrastriate visual area...... information when either a motor or a perceptual representation is used. Participants viewed two identical sequences of visual stimuli and used the information differently to perform either a temporal reproduction or a temporal estimation task. By comparing brain activity evoked by these tasks and control...... conditions, we explored commonalities and differences in brain areas involved in reproduction and estimation of temporal intervals. The basal ganglia and the cerebellum were commonly active in both temporal tasks, consistent with suggestions that perception and production of time are subserved by the same...

  11. The encoding of temporally irregular and regular visual patterns in the human brain.

    Directory of Open Access Journals (Sweden)

    Semir Zeki

    2008-05-01

    Full Text Available In the work reported here, we set out to study the neural systems that detect predictable temporal patterns and departures from them. We used functional magnetic resonance imaging (fMRI to locate activity in the brains of subjects when they viewed temporally regular and irregular patterns produced by letters, numbers, colors and luminance. Activity induced by irregular sequences was located within dorsolateral prefrontal cortex, including an area that was responsive to irregular patterns regardless of the type of visual stimuli producing them. Conversely, temporally regular arrangements resulted in activity in the right frontal lobe (medial frontal gyrus, in the left orbito-frontal cortex and in the left pallidum. The results show that there is an abstractive system in the brain for detecting temporal irregularity, regardless of the source producing it.

  12. Modulation of Temporally Coherent Brain Networks Estimated Using ICA at Rest and During Cognitive Tasks

    OpenAIRE

    Calhoun, Vince D.; Kiehl, Kent A.; Pearlson, Godfrey D.

    2008-01-01

    Brain regions which exhibit temporally coherent fluctuations, have been increasingly studied using functional magnetic resonance imaging (fMRI). Such networks are often identified in the context of an fMRI scan collected during rest (and thus are called “resting state networks”); however, they are also present during (and modulated by) the performance of a cognitive task. In this article, we will refer to such networks as temporally coherent networks (TCNs). Although there is still some debat...

  13. Identification of neural firing patterns, frequency and temporal coding mechanisms in individual aortic baroreceptors

    Directory of Open Access Journals (Sweden)

    Huaguang eGu

    2015-08-01

    Full Text Available In rabbit depressor nerve fibers, an on-off firing pattern, period-1 firing, and integer multiple firing with quiescent state were observed as the static pressure level was increased. A bursting pattern with bursts at the systolic phase of blood pressure, continuous firing, and bursting with burst at diastolic phase and quiescent state at systolic phase were observed as the mean level of the dynamic blood pressure was increased. For both static and dynamic pressures, the firing frequency of the first two firing patterns increased and of the last firing pattern decreased due to the quiescent state. If the quiescent state is disregarded, the spike frequency becomes an increasing trend. The instantaneous spike frequency of the systolic phase bursting, continuous firing, and diastolic phase bursting can reflect the temporal process of the systolic phase, whole procedure, and diastolic phase of the dynamic blood pressure signal, respectively. With increasing the static current corresponding to pressure level, the deterministic Hodgkin-Huxley (HH model manifests a process from a resting state first to period-1 firing via a subcritical Hopf bifurcation and then to a resting state via a supercritical Hopf bifurcation, and the firing frequency increases. The on-off firing and integer multiple firing were here identified as noise-induced firing patterns near the subcritical and supercritical Hopf bifurcation points, respectively, using the stochastic HH model. The systolic phase bursting and diastolic phase bursting were identified as pressure-induced firings near the subcritical and supercritical Hopf bifurcation points, respectively, using an HH model with a dynamic signal. The firing, spike frequency, and instantaneous spike frequency observed in the experiment were simulated and explained using HH models. The results illustrate the dynamics of different firing patterns and the frequency and temporal coding mechanisms of aortic baroreceptor.

  14. EEG Based Inference of Spatio-Temporal Brain Dynamics

    DEFF Research Database (Denmark)

    Hansen, Sofie Therese

    investigate the extraction of EEG components having bandpower dynamics correlated with fMRI components. We show that adding anatomical information to the inference scheme improves the recovery of correlated components compared to only using functional information. The anatomical information is incorporated......Electroencephalography (EEG) provides a measure of brain activity and has improved our understanding of the brain immensely. However, there is still much to be learned and the full potential of EEG is yet to be realized. In this thesis we suggest to improve the information gain of EEG using three...... different approaches; 1) by recovery of the EEG sources, 2) by representing and inferring the propagation path of EEG sources, and 3) by combining EEG with functional magnetic resonance imaging (fMRI). The common goal of the methods, and thus of this thesis, is to improve the spatial dimension of EEG...

  15. Temporal filtering of longitudinal brain magnetic resonance images for consistent segmentation

    Directory of Open Access Journals (Sweden)

    Snehashis Roy

    2016-01-01

    Full Text Available Longitudinal analysis of magnetic resonance images of the human brain provides knowledge of brain changes during both normal aging as well as the progression of many diseases. Previous longitudinal segmentation methods have either ignored temporal information or have incorporated temporal consistency constraints within the algorithm. In this work, we assume that some anatomical brain changes can be explained by temporal transitions in image intensities. Once the images are aligned in the same space, the intensities of each scan at the same voxel constitute a temporal (or 4D intensity trend at that voxel. Temporal intensity variations due to noise or other artifacts are corrected by a 4D intensity-based filter that smooths the intensity values where appropriate, while preserving real anatomical changes such as atrophy. Here smoothing refers to removal of sudden changes or discontinuities in intensities. Images processed with the 4D filter can be used as a pre-processing step to any segmentation method. We show that such a longitudinal pre-processing step produces robust and consistent longitudinal segmentation results, even when applying 3D segmentation algorithms. We compare with state-of-the-art 4D segmentation algorithms. Specifically, we experimented on three longitudinal datasets containing 4–12 time-points, and showed that the 4D temporal filter is more robust and has more power in distinguishing between healthy subjects and those with dementia, mild cognitive impairment, as well as different phenotypes of multiple sclerosis.

  16. Brain-derived neurotrophic factor ameliorates brain stem cardiovascular dysregulation during experimental temporal lobe status epilepticus.

    Directory of Open Access Journals (Sweden)

    Ching-Yi Tsai

    Full Text Available BACKGROUND: Status epilepticus (SE is an acute, prolonged epileptic crisis with a mortality rate of 20-30%; the underlying mechanism is not completely understood. We assessed the hypothesis that brain stem cardiovascular dysregulation occurs during SE because of oxidative stress in rostral ventrolateral medulla (RVLM, a key nucleus of the baroreflex loop; to be ameliorated by brain-derived neurotrophic factor (BDNF via an antioxidant action. METHODOLOGY/PRINCIPAL FINDINGS: In a clinically relevant experimental model of temporal lobe SE (TLSE using Sprague-Dawley rats, sustained hippocampal seizure activity was accompanied by progressive hypotension that was preceded by a reduction in baroreflex-mediated sympathetic vasomotor tone; heart rate and baroreflex-mediated cardiac responses remained unaltered. Biochemical experiments further showed concurrent augmentation of superoxide anion, phosphorylated p47(phox subunit of NADPH oxidase and mRNA or protein levels of BDNF, tropomyosin receptor kinase B (TrkB, angiotensin AT1 receptor subtype (AT1R, nitric oxide synthase II (NOS II or peroxynitrite in RVLM. Whereas pretreatment by microinjection bilaterally into RVLM of a superoxide dismutase mimetic (tempol, a specific antagonist of NADPH oxidase (apocynin or an AT1R antagonist (losartan blunted significantly the augmented superoxide anion or phosphorylated p47(phox subunit in RVLM, hypotension and the reduced baroreflex-mediated sympathetic vasomotor tone during experimental TLSE, pretreatment with a recombinant human TrkB-Fc fusion protein or an antisense bdnf oligonucleotide significantly potentiated all those events, alongside peroxynitrite. However, none of the pretreatments affected the insignificant changes in heart rate and baroreflex-mediated cardiac responses. CONCLUSIONS/SIGNIFICANCE: We conclude that formation of peroxynitrite by a reaction between superoxide anion generated by NADPH oxidase in RVLM on activation by AT1R and NOS II

  17. Entracking as a Brain Stem Code for Pitch: The Butte Hypothesis.

    Science.gov (United States)

    Joris, Philip X

    2016-01-01

    The basic nature of pitch is much debated. A robust code for pitch exists in the auditory nerve in the form of an across-fiber pooled interspike interval (ISI) distribution, which resembles the stimulus autocorrelation. An unsolved question is how this representation can be "read out" by the brain. A new view is proposed in which a known brain-stem property plays a key role in the coding of periodicity, which I refer to as "entracking", a contraction of "entrained phase-locking". It is proposed that a scalar rather than vector code of periodicity exists by virtue of coincidence detectors that code the dominant ISI directly into spike rate through entracking. Perfect entracking means that a neuron fires one spike per stimulus-waveform repetition period, so that firing rate equals the repetition frequency. Key properties are invariance with SPL and generalization across stimuli. The main limitation in this code is the upper limit of firing (~ 500 Hz). It is proposed that entracking provides a periodicity tag which is superimposed on a tonotopic analysis: at low SPLs and fundamental frequencies > 500 Hz, a spectral or place mechanism codes for pitch. With increasing SPL the place code degrades but entracking improves and first occurs in neurons with low thresholds for the spectral components present. The prediction is that populations of entracking neurons, extended across characteristic frequency, form plateaus ("buttes") of firing rate tied to periodicity.

  18. Temporal and spatial evolution of brain network topology during the first two years of life.

    Directory of Open Access Journals (Sweden)

    Wei Gao

    Full Text Available The mature brain features high wiring efficiency for information transfer. However, the emerging process of such an efficient topology remains elusive. With resting state functional MRI and a large cohort of normal pediatric subjects (n = 147 imaged during a critical time period of brain development, 3 wk- to 2 yr-old, the temporal and spatial evolution of brain network topology is revealed. The brain possesses the small world topology immediately after birth, followed by a remarkable improvement in whole brain wiring efficiency in 1 yr olds and becomes more stable in 2 yr olds. Regional developments of brain wiring efficiency and the evolution of functional hubs suggest differential development trend for primary and higher order cognitive functions during the first two years of life. Simulations of random errors and targeted attacks reveal an age-dependent improvement of resilience. The lower resilience to targeted attack observed in 3 wk old group is likely due to the fact that there are fewer well-established long-distance functional connections at this age whose elimination might have more profound implications in the overall efficiency of information transfer. Overall, our results offer new insights into the temporal and spatial evolution of brain topology during early brain development.

  19. Neural coding of movement direction in the healthy human brain.

    Directory of Open Access Journals (Sweden)

    Christopher D Cowper-Smith

    2010-10-01

    Full Text Available Neurophysiological studies in monkeys show that activity of neurons in primary cortex (M1, pre-motor cortex (PMC, and cerebellum varies systematically with the direction of reaching movements. These neurons exhibit preferred direction tuning, where the level of neural activity is highest when movements are made in the preferred direction (PD, and gets progressively lower as movements are made at increasing degrees of offset from the PD. Using a functional magnetic resonance imaging adaptation (fMRI-A paradigm, we show that PD coding does exist in regions of the human motor system that are homologous to those observed in non-human primates. Consistent with predictions of the PD model, we show adaptation (i.e., a lower level of the blood oxygen level dependent (BOLD time-course signal in M1, PMC, SMA, and cerebellum when consecutive wrist movements were made in the same direction (0° offset relative to movements offset by 90° or 180°. The BOLD signal in dorsolateral prefrontal cortex adapted equally in all movement offset conditions, mitigating against the possibility that the present results are the consequence of differential task complexity or attention to action in each movement offset condition.

  20. On gray dancing: Constructions of age-normality through choreography and temporal codes.

    Science.gov (United States)

    Krekula, Clary; Arvidson, Markus; Heikkinen, Satu; Henriksson, Andreas; Olsson, Eva

    2017-08-01

    Against the background of population aging, older peoples dance has attracted attention in research and its health promoting effects and social meanings have been brought to the fore. In this article we focus on the context and power dimensions of dance with an emphasis on the organizing of dance among older adults in terms of social discourses and age relationships. On the basis of qualitative interviews with 33 older dancers and 11 dance providers in Sweden, the study illustrates how dance is organized through social discourses on healthism and on the increasing group of older people as a powerful consumer group. The study highlights that older people and their social dance contexts are marked and subordinated in relation to younger age groups through non-verbal practices such as choreography and temporal codes. In short, dancing among older adults is not only a common health promoting and social activity, but also an arena in which age and age normality are negotiated and constructed. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  1. Mnemonic networks in the hippocampal formation: from spatial maps to temporal and conceptual codes.

    Science.gov (United States)

    Milivojevic, Branka; Doeller, Christian F

    2013-11-01

    The hippocampal formation has been associated with a wide variety of functions including spatial navigation and planning, memory encoding and retrieval, relational processing, novelty detection, and imagination. These functions are dissimilar in terms of their behavioral consequences and modality of representation. Consequently, theoretical standpoints have focused on explaining the role of the hippocampal formation in terms of either its spatial or nonspatial functions. Contrary to this dichotomy, we propose that it is essential to look beyond these traditional boundaries between mnemonic and spatial functions and focus instead on the processes that these functions have in common. In this framework, we use electrophysiology data from the spatial domain to predict effects on the systems level, both in spatial and nonspatial domains. We initially outline the results of studies that have used findings from spatial navigation in rodents to predict the patterns of brain activity observable in people who are exploring virtual environments. We discuss how certain properties of space-defining neurons enable space to be represented as a mental map of interconnected locations, which are expressed at multiple spatial scales in separate modules in the hippocampal formation. We then suggest that memories are also organized in networks, characterized by mnemonic and temporal hierarchies. We finish by discussing how virtual-reality techniques can be used to create novel lifelike episodes allowing us to look at episodic memory processes while multivariate analysis tools can be used to explore the organizational structure of mnemonic networks. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  2. Temporal changes of Japanese encephalitits virus in different brain regions of rat

    Directory of Open Access Journals (Sweden)

    Ruchi Srivastava

    2013-01-01

    Full Text Available Background & objectives: Japanese encephalitis virus (JEV infection results in acute encephalitic illness. The affinity of JEV to different regions of brain and temporal changes in viral load have not been studied. This study was conducted to describe localization of JEV to different regions of the brain at different stages of disease in a rat model of Japanese encephalitis (JE. Methods: Twelve days old Wistar rats were inoculated intracerebrally with a dose of 3 x 10 6 pfu/ml of JEV. After 3, 6, 10 and 20 days post-inoculation, brains were dissected out and different regions of brain (cortex, striatum, thalamus and mid brain were taken. Motor deficit was assessed by the rota rod and JEV RNA copies were evaluated using real-time PCR assay. Results: There was a significant increase in motor deficit in rats inoculated with JEV compared to the controls. JEV RNA copies were present in all studied regions of the brain on days 3, 6 and 10 post-inoculation. Maximum number of JEV RNA copies were present in the mid brain on days 3 and 10 post-inoculation. JEV RNA copies were not detected in any of the brain regions on day 20. Interpretation & conclusions: This study reports JEV RNA load in different brain regions of rat with higher affinity of JEV virus to thalamus and mid brain compared to other regions.

  3. Role of blood-brain barrier in temporal lobe epilepsy and pharmacoresistance

    NARCIS (Netherlands)

    van Vliet, E.A.; Aronica, E.; Gorter, J.A.

    2014-01-01

    Temporal lobe epilepsy (TLE) is the most common form of focal epilepsies in adults. It is often initiated by an insult or brain injury which triggers a series of alterations which ultimately lead to seizures (epilepsy). In 50-70% of people with TLE the condition cannot be adequately treated by the

  4. Consciousness and the brain deciphering how the brain codes our thoughts

    CERN Document Server

    Dehaene, Stanislas

    2014-01-01

    How does our brain generate a conscious thought? And why does so much of our knowledge remain unconscious? Thanks to clever psychological and brain-imaging experiments, scientists are closer to cracking this mystery than ever before. In this lively book, Stanislas Dehaene describes the pioneering work his lab and the labs of other cognitive neuroscientists worldwide have accomplished in defining, testing, and explaining the brain events behind a conscious state. We can now pin down the neurons that fire when a person reports becoming aware of a piece of information and understand the crucial role unconscious computations play in how we make decisions. The emerging theory enables a test of consciousness in animals, babies, and those with severe brain injuries. A joyous exploration of the mind and its thrilling complexities, Consciousness and the Brain will excite anyone interested in cutting-edge science and technology and the vast philosophical, personal, and ethical implications of finally quantifying cons...

  5. MRI and brain spect findings in patients with unilateral temporal lobe epilepsy and normal CT scan

    Directory of Open Access Journals (Sweden)

    P.G. Carrilho

    1994-06-01

    Full Text Available 26 patients with temporal lobe epilepsy clinically documented by several abnormal interictal surface EEGs with typical unitemporal epileptiform activity and a normal CT scan were studied. Interictal99mTC HMPAO brain SPECT and MRI were performed in all subjects. Abnormalities were shown in 61.5% of MRI (n=16 and 65.4% of SPECT (n=17. Hippocampal atrophy associated to a high signal on T2-weighted MRI slices suggesting mesial temporal sclerosis was the main finding (n=12; 75% of abnormal MRI. MRI correlated well to surface EEG in 50% (n=13. There was also a good correlation between MRI and SPECT in 30.7% (n=8. SPECT and EEG were in agreement in 57.7% (n=l5. MRI, SPECT and EEG were congruent in 26.9% (n=7. These results support the usefulness of interictal brain SPECT and MRI in detecting lateralized abnormalities in temporal lobe epilepsy. On the other hand, in two cases, interictal SPECT correlated poorly with surface EEG. This functional method should not be used isolately in the detection of temporal lobe foci. MRI is more useful than CT as a neuroimaging technique in temporal lobe epilepsy. It may detect small structural lesions and mesial temporal lobe sclerosis which are not easily seen with traditional CT scanning.

  6. Temporally Coordinated Deep Brain Stimulation in the Dorsal and Ventral Striatum Synergistically Enhances Associative Learning.

    Science.gov (United States)

    Katnani, Husam A; Patel, Shaun R; Kwon, Churl-Su; Abdel-Aziz, Samer; Gale, John T; Eskandar, Emad N

    2016-01-04

    The primate brain has the remarkable ability of mapping sensory stimuli into motor behaviors that can lead to positive outcomes. We have previously shown that during the reinforcement of visual-motor behavior, activity in the caudate nucleus is correlated with the rate of learning. Moreover, phasic microstimulation in the caudate during the reinforcement period was shown to enhance associative learning, demonstrating the importance of temporal specificity to manipulate learning related changes. Here we present evidence that extends upon our previous finding by demonstrating that temporally coordinated phasic deep brain stimulation across both the nucleus accumbens and caudate can further enhance associative learning. Monkeys performed a visual-motor associative learning task and received stimulation at time points critical to learning related changes. Resulting performance revealed an enhancement in the rate, ceiling, and reaction times of learning. Stimulation of each brain region alone or at different time points did not generate the same effect.

  7. Distinct Patterns of Temporal and Directional Connectivity among Intrinsic Networks in the Human Brain.

    Science.gov (United States)

    Shine, James M; Kucyi, Aaron; Foster, Brett L; Bickel, Stephan; Wang, Danhong; Liu, Hesheng; Poldrack, Russell A; Hsieh, Liang-Tien; Hsiang, Jen Chun; Parvizi, Josef

    2017-10-04

    To determine the spatiotemporal relationships among intrinsic networks of the human brain, we recruited seven neurosurgical patients (four males and three females) who were implanted with intracranial depth electrodes. We first identified canonical resting-state networks at the individual subject level using an iterative matching procedure on each subject's resting-state fMRI data. We then introduced single electrical pulses to fMRI pre-identified nodes of the default network (DN), frontoparietal network (FPN), and salience network (SN) while recording evoked responses in other recording sites within the same networks. We found bidirectional signal flow across the three networks, albeit with distinct patterns of evoked responses within different time windows. We used a data-driven clustering approach to show that stimulation of the FPN and SN evoked a rapid (130 ms) in other nodes of the DN, as well as FPN and SN. Our results provide temporal information about the patterns of signal flow between intrinsic networks that provide insights into the spatiotemporal dynamics that are likely to constrain the architecture of the brain networks supporting human cognition and behavior. SIGNIFICANCE STATEMENT Despite great progress in the functional neuroimaging of the human brain, we still do not know the precise set of rules that define the patterns of temporal organization between large-scale networks of the brain. In this study, we stimulated and then recorded electrical evoked potentials within and between three large-scale networks of the brain, the default network (DN), frontoparietal network (FPN), and salience network (SN), in seven subjects undergoing invasive neurosurgery. Using a data-driven clustering approach, we observed distinct temporal and directional patterns between the three networks, with FPN and SN activity predominant in early windows and DN stimulation affecting the network in later windows. These results provide important temporal information about

  8. The neural basis of temporal individuation and its capacity limits in the human brain.

    Science.gov (United States)

    Naughtin, Claire K; Tamber-Rosenau, Benjamin J; Dux, Paul E

    2017-11-01

    Individuation refers to individuals' use of spatial and temporal properties to register objects as distinct perceptual events relative to other stimuli. Although behavioral studies have examined both spatial and temporal individuation, neuroimaging investigations have been restricted to the spatial domain and at relatively late stages of information processing. Here, we used univariate and multivoxel pattern analyses of functional MRI data to identify brain regions involved in individuating temporally distinct visual items and the neural consequences that arise when this process reaches its capacity limit (repetition blindness, RB). First, we found that regional patterns of blood-oxygen-level-dependent activity across the cortex discriminated between instances where repeated and nonrepeated stimuli were successfully individuated-conditions that placed differential demands on temporal individuation. These results could not be attributed to repetition suppression or other stimulus-related factors, task difficulty, regional activation differences, other capacity-limited processes, or artifacts in the data or analyses. Contrary to current theoretical models, this finding suggests that temporal individuation is supported by a distributed set of brain regions, rather than a single neural correlate. Second, conditions that reflect the capacity limit of individuation-instances of RB-lead to changes in the spatial patterns within this network, as well as amplitude changes in the left hemisphere premotor cortex, superior medial frontal cortex, anterior cingulate cortex, and bilateral parahippocampal place area. These findings could not be attributed to response conflict/ambiguity and likely reflect the core brain regions and mechanisms that underlie the capacity-limited process that gives rise to RB.NEW & NOTEWORTHY We present novel findings into the neural bases of temporal individuation and repetition blindness (RB)-the perceptual deficit that arises when this process

  9. Temporal Fine-Structure Coding and Lateralized Speech Perception in Normal-Hearing and Hearing-Impaired Listeners

    DEFF Research Database (Denmark)

    Locsei, Gusztav; Pedersen, Julie Hefting; Laugesen, Søren

    2016-01-01

    This study investigated the relationship between speech perception performance in spatially complex, lateralized listening scenarios and temporal fine-structure (TFS) coding at low frequencies. Young normal-hearing (NH) and two groups of elderly hearing-impaired (HI) listeners with mild or moderate...... gains to the stimuli, which were presented over headphones. The target and masker streams were lateralized to the same or to opposite sides of the head by introducing 0.7-ms interaural time differences between the ears. TFS coding was assessed by measuring frequency discrimination thresholds...

  10. A human-specific de novo protein-coding gene associated with human brain functions.

    Directory of Open Access Journals (Sweden)

    Chuan-Yun Li

    2010-03-01

    Full Text Available To understand whether any human-specific new genes may be associated with human brain functions, we computationally screened the genetic vulnerable factors identified through Genome-Wide Association Studies and linkage analyses of nicotine addiction and found one human-specific de novo protein-coding gene, FLJ33706 (alternative gene symbol C20orf203. Cross-species analysis revealed interesting evolutionary paths of how this gene had originated from noncoding DNA sequences: insertion of repeat elements especially Alu contributed to the formation of the first coding exon and six standard splice junctions on the branch leading to humans and chimpanzees, and two subsequent substitutions in the human lineage escaped two stop codons and created an open reading frame of 194 amino acids. We experimentally verified FLJ33706's mRNA and protein expression in the brain. Real-Time PCR in multiple tissues demonstrated that FLJ33706 was most abundantly expressed in brain. Human polymorphism data suggested that FLJ33706 encodes a protein under purifying selection. A specifically designed antibody detected its protein expression across human cortex, cerebellum and midbrain. Immunohistochemistry study in normal human brain cortex revealed the localization of FLJ33706 protein in neurons. Elevated expressions of FLJ33706 were detected in Alzheimer's brain samples, suggesting the role of this novel gene in human-specific pathogenesis of Alzheimer's disease. FLJ33706 provided the strongest evidence so far that human-specific de novo genes can have protein-coding potential and differential protein expression, and be involved in human brain functions.

  11. Regulatory consequences of neuronal ELAV-like protein binding to coding and non-coding RNAs in human brain

    Science.gov (United States)

    Scheckel, Claudia; Drapeau, Elodie; Frias, Maria A; Park, Christopher Y; Fak, John; Zucker-Scharff, Ilana; Kou, Yan; Haroutunian, Vahram; Ma'ayan, Avi

    2016-01-01

    Neuronal ELAV-like (nELAVL) RNA binding proteins have been linked to numerous neurological disorders. We performed crosslinking-immunoprecipitation and RNAseq on human brain, and identified nELAVL binding sites on 8681 transcripts. Using knockout mice and RNAi in human neuroblastoma cells, we showed that nELAVL intronic and 3' UTR binding regulates human RNA splicing and abundance. We validated hundreds of nELAVL targets among which were important neuronal and disease-associated transcripts, including Alzheimer's disease (AD) transcripts. We therefore investigated RNA regulation in AD brain, and observed differential splicing of 150 transcripts, which in some cases correlated with differential nELAVL binding. Unexpectedly, the most significant change of nELAVL binding was evident on non-coding Y RNAs. nELAVL/Y RNA complexes were specifically remodeled in AD and after acute UV stress in neuroblastoma cells. We propose that the increased nELAVL/Y RNA association during stress may lead to nELAVL sequestration, redistribution of nELAVL target binding, and altered neuronal RNA splicing. DOI: http://dx.doi.org/10.7554/eLife.10421.001 PMID:26894958

  12. Multiple frequencies sequential coding for SSVEP-based brain-computer interface.

    Directory of Open Access Journals (Sweden)

    Yangsong Zhang

    Full Text Available BACKGROUND: Steady-state visual evoked potential (SSVEP-based brain-computer interface (BCI has become one of the most promising modalities for a practical noninvasive BCI system. Owing to both the limitation of refresh rate of liquid crystal display (LCD or cathode ray tube (CRT monitor, and the specific physiological response property that only a very small number of stimuli at certain frequencies could evoke strong SSVEPs, the available frequencies for SSVEP stimuli are limited. Therefore, it may not be enough to code multiple targets with the traditional frequencies coding protocols, which poses a big challenge for the design of a practical SSVEP-based BCI. This study aimed to provide an innovative coding method to tackle this problem. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we present a novel protocol termed multiple frequencies sequential coding (MFSC for SSVEP-based BCI. In MFSC, multiple frequencies are sequentially used in each cycle to code the targets. To fulfill the sequential coding, each cycle is divided into several coding epochs, and during each epoch, certain frequency is used. Obviously, different frequencies or the same frequency can be presented in the coding epochs, and the different epoch sequence corresponds to the different targets. To show the feasibility of MFSC, we used two frequencies to realize four targets and carried on an offline experiment. The current study shows that: 1 MFSC is feasible and efficient; 2 the performance of SSVEP-based BCI based on MFSC can be comparable to some existed systems. CONCLUSIONS/SIGNIFICANCE: The proposed protocol could potentially implement much more targets with the limited available frequencies compared with the traditional frequencies coding protocol. The efficiency of the new protocol was confirmed by real data experiment. We propose that the SSVEP-based BCI under MFSC might be a promising choice in the future.

  13. How can a recurrent neurodynamic predictive coding model cope with fluctuation in temporal patterns? Robotic experiments on imitative interaction.

    Science.gov (United States)

    Ahmadi, Ahmadreza; Tani, Jun

    2017-08-01

    The current paper examines how a recurrent neural network (RNN) model using a dynamic predictive coding scheme can cope with fluctuations in temporal patterns through generalization in learning. The conjecture driving this present inquiry is that a RNN model with multiple timescales (MTRNN) learns by extracting patterns of change from observed temporal patterns, developing an internal dynamic structure such that variance in initial internal states account for modulations in corresponding observed patterns. We trained a MTRNN with low-dimensional temporal patterns, and assessed performance on an imitation task employing these patterns. Analysis reveals that imitating fluctuated patterns consists in inferring optimal internal states by error regression. The model was then tested through humanoid robotic experiments requiring imitative interaction with human subjects. Results show that spontaneous and lively interaction can be achieved as the model successfully copes with fluctuations naturally occurring in human movement patterns. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Effects of sensorineural hearing loss on temporal coding of narrowband and broadband signals in the auditory periphery.

    Science.gov (United States)

    Henry, Kenneth S; Heinz, Michael G

    2013-09-01

    People with sensorineural hearing loss have substantial difficulty understanding speech under degraded listening conditions. Behavioral studies suggest that this difficulty may be caused by changes in auditory processing of the rapidly-varying temporal fine structure (TFS) of acoustic signals. In this paper, we review the presently known effects of sensorineural hearing loss on processing of TFS and slower envelope modulations in the peripheral auditory system of mammals. Cochlear damage has relatively subtle effects on phase locking by auditory-nerve fibers to the temporal structure of narrowband signals under quiet conditions. In background noise, however, sensorineural loss does substantially reduce phase locking to the TFS of pure-tone stimuli. For auditory processing of broadband stimuli, sensorineural hearing loss has been shown to severely alter the neural representation of temporal information along the tonotopic axis of the cochlea. Notably, auditory-nerve fibers innervating the high-frequency part of the cochlea grow increasingly responsive to low-frequency TFS information and less responsive to temporal information near their characteristic frequency (CF). Cochlear damage also increases the correlation of the response to TFS across fibers of varying CF, decreases the traveling-wave delay between TFS responses of fibers with different CFs, and can increase the range of temporal modulation frequencies encoded in the periphery for broadband sounds. Weaker neural coding of temporal structure in background noise and degraded coding of broadband signals along the tonotopic axis of the cochlea are expected to contribute considerably to speech perception problems in people with sensorineural hearing loss. This article is part of a Special Issue entitled "Annual Reviews 2013". Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Whole-brain voxel-based morphometry of white matter in medial temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Yu Aihong [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China); Li Kuncheng [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China)], E-mail: Likuncheng@vip.sina.com; Li Lin; Shan Baoci [Institute of High Energy Physics, Chinese Academy of Sciences (China); Wang Yuping; Xue Sufang [Department of Neurology, Xuanwu Hospital, Capital University of Medical Sciences (China)

    2008-01-15

    Purpose: The purpose of this study was to analyze whole-brain white matter changes in medial temporal lobe epilepsy (MTLE). Materials and methods: We studied 23 patients with MTLE and 13 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The seizure focus was right sided in 11 patients and left sided in 12. The data were collected on a 1.5 T MR system and analyzed by SPM 99 to generate white matter density maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MTLE prominently including bilateral frontal lobes, bilateral temporal lobes and corpus callosum. White matter reduction was also found in the bilateral cerebellar hemispheres in the left MTLE group. Conclusion: VBM is a simple and automated approach that is able to identify diffuse whole-brain white matter reduction in MTLE.

  16. Efficacy of the transtemporal approach with awake brain mapping to reach the dominant posteromedial temporal lesions.

    Science.gov (United States)

    Iijima, Kentaro; Motomura, Kazuya; Chalise, Lushun; Hirano, Masaki; Natsume, Atsushi; Wakabayashi, Toshihiko

    2017-01-01

    Surgeries for lesions in the dominant hippocampal and parahippocampal gyrus involving the posteromedial temporal regions are challenging to perform because they are located close to Wernicke's area; white matter fibers related with language; the optic radiations; and critical neurovascular structures. We performed a transtemporal approach with awake functional mapping for lesions affecting the dominant posteromedial temporal regions. The aim of this study was to assess the feasibility, safety, and efficacy of awake craniotomy for these lesions. We retrospectively reviewed four consecutive patients with tumors or cavernous angiomas located in the left hippocampal and parahippocampal gyrus, which further extended to the posteromedial temporal regions, who underwent awake surgery between December 2014 and January 2016. Four patients with lesions associated with the left hippocampal and parahippocampal gyrus, including the posteromedial temporal area, who underwent awake surgery were registered in the study. In all four patients, cortical and subcortical eloquent areas were identified via direct electrical stimulation. This allowed determination of the optimal surgical route to the angioma or tumor, even in the language-dominant hippocampal and parahippocampal gyrus. In particular, this approach enabled access to the upper part of posteromedial temporal lesions, while protecting the subcortical language-related fibers, such as the superior longitudinal fasciculus. This study revealed that awake brain mapping can enable the safe resection of dominant posteromedial temporal lesions, while protecting cortical and subcortical eloquent areas. Furthermore, our experience with four patients demonstrates the feasibility, safety, and efficacy of awake surgery for these lesions.

  17. Evaluation of seizure propagation on ictal brain SPECT using statistical parametric mapping in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Tae Joo; Lee, Jong Doo; Kim, Hee Joung; Lee, Byung In; Kim, Ok Joon; Kim, Min Jung [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of); Jeon, Jeong Dong [College of Medicine, Inje Univ., Pusan (Korea, Republic of)

    1999-07-01

    Ictal brain SPECT has a high diagnostic sensitivity exceeding 90 % in the localization of seizure focus, however, it often shows increased uptake within the extratemporal areas due to early propagation of seizure discharge. This study aimed to evaluate seizure propagation on ictal brian SPECT in patients with temporal lobe epilepsy (TLE) by statistical parametric mapping (SPM). Twenty-one patients (age 27.14 5.79 y) with temporal lobe epilepsy (right in 8, left in 13) who had successful seizure outcome after surgery and nine normal control were included. The data of ictal and interictal brain SPECT of the patients and baseline SPECT of normal control group were analyzed using automatic image registration and SPM96 softwares. The statistical analysis was performed to compare the mean SPECT image of normal group with individual ictal SPECT, and each mean image of the interictal groups of the right or left TLE with individual ictal scans. The t statistic SPM [t] was transformed to SPM [Z] with a threshold of 1.64. The statistical results were displayed and rendered on the reference 3 dimensional MRI images with P value of 0.05 and uncorrected extent threshold p value of 0.5 for SPM [Z]. SPM data demonstrated increased uptake within the epileptic lesion in 19 patients (90.4 %), among them, localized increased uptake confined to the epileptogenic lesion was seen in only 4 (19%) but 15 patients (71.4%) showed hyperperfusion within propagation sites. Bi-temporal hyperperfusion was observed in 11 out of 19 patients (57.9%, 5 in the right and 6 in the left); higher uptake within the lesion than contralateral side in 9, similar activity in 1 and higher uptake within contralateral lobe in one. Extra-temporal hyperperfusion was observed in 8 (2 in the right, 3 in the left, 3 in bilateral); unilateral hyperperfusion within the epileptogenic temporal lobe and extra-temporal area in 4, bi-temporal with extra-temporal hyperperfusion in remaining 4. Ictal brain SPECT is highly

  18. Disturbed prefrontal and temporal brain function during emotion and cognition interaction in criminal psychopathy.

    Science.gov (United States)

    Müller, Jürgen L; Sommer, Monika; Döhnel, Katrin; Weber, Tatjana; Schmidt-Wilcke, Tobias; Hajak, Göran

    2008-01-01

    Impaired emotional responsiveness has been revealed as a hallmark of psychopathy. In spite of an increasing database on emotion processing, studies on cognitive function and in particular on the impact of emotion on cognition in psychopathy are rare. We used pictures from the International Affective Picture Set (IAPS) and a Simon Paradigm to address emotion-cognition interaction while functional and structural imaging data were obtained in 12 healthy controls and 10 psychopaths. We found an impaired emotion-cognition interaction in psychopaths that correlated with a changed prefrontal and temporal brain activation. With regard to the temporal cortex, it is shown that structure and function of the right superior temporal gyrus is disturbed in psychopathy, supporting a neurobiological approach to psychopathy, in which structure and function of the right STG may be important. (c) 2008 John Wiley & Sons, Ltd.

  19. Specialization of left auditory cortex for speech perception in man depends on temporal coding

    National Research Council Canada - National Science Library

    Liégeois-Chauvel, C; de Graaf, J B; Laguitton, V; Chauvel, P

    1999-01-01

    ...). Natural voiced /ba/, /da/, /ga/) and voiceless (/pa/, /ta/, /ka/) syllables, spoken by a native French speaker, were used to study the processing of a specific temporally based acoustico-phonetic feature, the voice onset time (VOT...

  20. Brain temporal complexity in explaining the therapeutic and cognitive effects of seizure therapy.

    Science.gov (United States)

    Farzan, Faranak; Atluri, Sravya; Mei, Ye; Moreno, Sylvain; Levinson, Andrea J; Blumberger, Daniel M; Daskalakis, Zafiris J

    2017-04-01

    Over 350 million people worldwide suffer from depression, a third of whom are medication-resistant. Seizure therapy remains the most effective treatment in depression, even when many treatments fail. The utility of seizure therapy is limited due to its cognitive side effects and stigma. The biological targets of seizure therapy remain unknown, hindering design of new treatments with comparable efficacy. Seizures impact the brains temporal dynamicity observed through electroencephalography. This dynamicity reflects richness of information processing across distributed brain networks subserving affective and cognitive processes. We investigated the hypothesis that seizure therapy impacts mood (depressive symptoms) and cognition by modulating brain temporal dynamicity. We obtained resting-state electroencephalography from 34 patients (age = 46.0 ± 14.0, 21 females) receiving two types of seizure treatments-electroconvulsive therapy or magnetic seizure therapy. We used multi-scale entropy to quantify the complexity of the brain's temporal dynamics before and after seizure therapy. We discovered that reduction of complexity in fine timescales underlined successful therapeutic response to both seizure treatments. Greater reduction in complexity of fine timescales in parieto-occipital and central brain regions was significantly linked with greater improvement in depressive symptoms. Greater increase in complexity of coarse timescales was associated with greater decline in cognition including the autobiographical memory. These findings were region and timescale specific. That is, change in complexity in occipital regions (e.g. O2 electrode or right occipital pole) at fine timescales was only associated with change in depressive symptoms, and not change in cognition, and change in complexity in parieto-central regions (e.g. Pz electrode or intra and transparietal sulcus) at coarser timescale was only associated with change in cognition, and not depressive symptoms. Finally

  1. Temporal profile of improvement of tardive dystonia after globus pallidus deep brain stimulation.

    Science.gov (United States)

    Shaikh, Aasef G; Mewes, Klaus; DeLong, Mahlon R; Gross, Robert E; Triche, Shirley D; Jinnah, H A; Boulis, Nicholas; Willie, Jon T; Freeman, Alan; Alexander, Garrett E; Aia, Pratibha; Butefisch, Cathrine M; Esper, Christine D; Factor, Stewart A

    2015-02-01

    Several case reports and small series have indicated that tardive dystonia is responsive to globus pallidus deep brain stimulation. Whether different subtypes or distributions of tardive dystonia are associated with different outcomes remains unknown. We assessed the outcomes and temporal profile of improvement of eight tardive dystonia patients who underwent globus pallidus deep brain stimulation over the past six years through record review. Due to the retrospective nature of this study, it was not blinded or placebo controlled. Consistent with previous studies, deep brain stimulation improved the overall the Burke-Fahn-Marsden motor scores by 85.1 ± 13.5%. The distributions with best responses in descending order were upper face, lower face, larynx/pharynx, limbs, trunk, and neck. Patients with prominent cervical dystonia demonstrated improvement in the Toronto Western Spasmodic Torticollis Rating Scale but improvements took several months. In four patients the effects of deep brain stimulation on improvement in Burke Fahn Marsden score was rapid, while in four cases there was partial rapid response of neck and trunk dystonia followed by was gradual resolution of residual symptoms over 48 months. Our retrospective analysis shows excellent resolution of tardive dystonia after globus pallidus deep brain stimulation. We found instantaneous response, except with neck and trunk dystonia where partial recovery was followed by further resolution at slower rate. Such outcome is encouraging for using deep brain stimulation in treatment of tardive dystonia. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Evaluation of ictal brain SPET using statistical parametric mapping in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.D.; Kim, H.-J.; Jeon, T.J.; Kim, M.J. [Div. of Nuclear Medicine, Yonsei University Medical College, Seoul (Korea); Lee, B.I.; Kim, O.J. [Dept. of Neurology, Yonsei University Medical College, Seoul (Korea)

    2000-11-01

    An automated voxel-based analysis of brain images using statistical parametric mapping (SPM) is accepted as a standard approach in the analysis of activation studies in positron emission tomography and functional magnetic resonance imaging. This study aimed to investigate whether or not SPM would increase the diagnostic yield of ictal brain single-photon emission tomography (SPET) in temporal lobe epilepsy (TLE). Twenty-one patients (age 27.14{+-}5.79 years) with temporal lobe epilepsy (right in 8, left in 13) who had a successful seizure outcome after surgery and nine normal subjects were included in the study. The data of ictal and interictal brain SPET of the patients and baseline SPET of the normal control group were analysed using SPM96 software. The t statistic SPM(t) was transformed to SPM(Z) with various thresholds of P<0.05, 0.005 and 0.001, and corrected extent threshold P value of 0.05. The SPM data were compared with the conventional ictal and interictal subtraction method. On group comparison, ictal SPET showed increased uptake within the epileptogenic mesial temporal lobe. On single case analysis, ictal SPET images correctly lateralized the epileptogenic temporal lobe in 18 cases, falsely lateralized it in one and failed to lateralize it in two as compared with the mean image of the normal group at a significance level of P<0.05. Comparing the individual ictal images with the corresponding interictal group, 15 patients were correctly lateralized, one was falsely lateralized and four were not lateralized. At significance levels of P<0.005 and P<0.001, correct lateralization of the epileptogenic temporal lobe was achieved in 15 and 13 patients, respectively, as compared with the normal group. On the other hand, when comparison was made with the corresponding interictal group, only 7 out of 21 patients were correctly lateralized at the threshold of P<0.005 and five at P<0.001. The result of the subtraction method was close to the single case analysis on

  3. Mapping brain response to pain in fibromyalgia patients using temporal analysis of FMRI.

    Directory of Open Access Journals (Sweden)

    Jesus Pujol

    Full Text Available BACKGROUND: Nociceptive stimuli may evoke brain responses longer than the stimulus duration often partially detected by conventional neuroimaging. Fibromyalgia patients typically complain of severe pain from gentle stimuli. We aimed to characterize brain response to painful pressure in fibromyalgia patients by generating activation maps adjusted for the duration of brain responses. METHODOLOGY/PRINCIPAL FINDINGS: Twenty-seven women (mean age: 47.8 years were assessed with fMRI. The sample included nine fibromyalgia patients and nine healthy subjects who received 4 kg/cm(2 of pressure on the thumb. Nine additional control subjects received 6.8 kg/cm(2 to match the patients for the severity of perceived pain. Independent Component Analysis characterized the temporal dynamics of the actual brain response to pressure. Statistical parametric maps were estimated using the obtained time courses. Brain response to pressure (18 seconds consistently exceeded the stimulus application (9 seconds in somatosensory regions in all groups. fMRI maps following such temporal dynamics showed a complete pain network response (sensory-motor cortices, operculo-insula, cingulate cortex, and basal ganglia to 4 kg/cm(2 of pressure in fibromyalgia patients. In healthy subjects, response to this low intensity pressure involved mainly somatosensory cortices. When matched for perceived pain (6.8 kg/cm(2, control subjects showed also comprehensive activation of pain-related regions, but fibromyalgia patients showed significantly larger activation in the anterior insula-basal ganglia complex and the cingulate cortex. CONCLUSIONS/SIGNIFICANCE: The results suggest that data-driven fMRI assessments may complement conventional neuroimaging for characterizing pain responses and that enhancement of brain activation in fibromyalgia patients may be particularly relevant in emotion-related regions.

  4. FMRI study relevant to the Mozart effect: brain areas involved in spatial-temporal reasoning.

    Science.gov (United States)

    Bodner, M; Muftuler, L T; Nalcioglu, O; Shaw, G L

    2001-10-01

    Behavioral studies, motivated by columnar cortical model predictions, have given evidence for music causally enhancing spatial-temporal reasoning. A wide range of behavioral experiments showed that listening to a Mozart Sonata (K.448) gave subsequent enhancements. An EEG coherence study gave evidence for a carryover from that Mozart Sonata listening condition to the subsequent spatial-temporal task in specific cortical regions. Here we present fMRI studies comparing cortical blood flow activation by the Mozart Sonata vs. other music. In addition to expected temporal cortex activation, we report dramatic statistically significant differences in activation by the Mozart Sonata (in comparison to Beethoven's Fur Elise and 1930s piano music) in dorsolateral pre-frontal cortex, occipital cortex and cerebellum, all expected to be important for spatial-temporal reasoning. It would be of great interest to explicitly test this expectation. We propose an fMRI study comparing (subject by subject) brain areas activated in music listening conditions and in spatial-temporal tasks.

  5. Analysis of spatio-temporal brain imaging patterns by Hidden Markov Models and serial MRI images.

    Science.gov (United States)

    Wang, Ying; Resnick, Susan M; Davatzikos, Christos

    2014-09-01

    Brain changes due to development and maturation, normal aging, or degenerative disease are continuous, gradual, and variable across individuals. To quantify the individual progression of brain changes, we propose a spatio-temporal methodology based on Hidden Markov Models (HMM), and apply it on four-dimensional structural brain magnetic resonance imaging series of older individuals. First, regional brain features are extracted in order to reduce image dimensionality. This process is guided by the objective of the study or the specific imaging patterns whose progression is of interest, for example, the evaluation of Alzheimer-like patterns of brain change in normal individuals. These regional features are used in conjunction with HMMs, which aim to measure the dynamic association between brain structure changes and progressive stages of disease over time. A bagging framework is used to obtain models with good generalization capability, since in practice the number of serial scans is limited. An application of the proposed methodology was to detect individuals with the risk of developing MCI, and therefore it was tested on modeling the progression of brain atrophy patterns in older adults. With HMM models, the state-transition paths corresponding to longitudinal brain changes were constructed from two completely independent datasets, the Alzheimer Disease Neuroimaging Initiative and the Baltimore Longitudinal Study of Aging. The statistical analysis of HMM-state paths among the normal, progressive MCI, and MCI groups indicates that, HMM-state index 1 is likely to be a predictor of the conversion from cognitively normal to MCI, potentially many years before clinical symptoms become measurable. Copyright © 2014 Wiley Periodicals, Inc.

  6. Roles of ON Cone Bipolar Cell Subtypes in Temporal Coding in the Mouse Retina

    Science.gov (United States)

    Fyk-Kolodziej, Bozena; Cohn, Jesse

    2014-01-01

    In the visual system, diverse image processing starts with bipolar cells, which are the second-order neurons of the retina. Thirteen subtypes of bipolar cells have been identified, which are thought to encode different features of image signaling and to initiate distinct signal-processing streams. Although morphologically identified, the functional roles of each bipolar cell subtype in visual signal encoding are not fully understood. Here, we investigated how ON cone bipolar cells of the mouse retina encode diverse temporal image signaling. We recorded bipolar cell voltage changes in response to two different input functions: sinusoidal light and step light stimuli. Temporal tuning in ON cone bipolar cells was diverse and occurred in a subtype-dependent manner. Subtypes 5s and 8 exhibited low-pass filtering property in response to a sinusoidal light stimulus, and responded with sustained fashion to step-light stimulation. Conversely, subtypes 5f, 6, 7, and XBC exhibited bandpass filtering property in response to sinusoidal light stimuli, and responded transiently to step-light stimuli. In particular, subtypes 7 and XBC were high-temporal tuning cells. We recorded responses in different ways to further examine the underlying mechanisms of temporal tuning. Current injection evoked low-pass filtering, whereas light responses in voltage-clamp mode produced bandpass filtering in all ON bipolar cells. These findings suggest that cone photoreceptor inputs shape bandpass filtering in bipolar cells, whereas intrinsic properties of bipolar cells shape low-pass filtering. Together, our results demonstrate that ON bipolar cells encode diverse temporal image signaling in a subtype-dependent manner to initiate temporal visual information-processing pathways. PMID:24966376

  7. Large-scale brain networks are distinctly affected in right and left mesial temporal lobe epilepsy.

    Science.gov (United States)

    de Campos, Brunno Machado; Coan, Ana Carolina; Lin Yasuda, Clarissa; Casseb, Raphael Fernandes; Cendes, Fernando

    2016-09-01

    Mesial temporal lobe epilepsy (MTLE) with hippocampus sclerosis (HS) is associated with functional and structural alterations extending beyond the temporal regions and abnormal pattern of brain resting state networks (RSNs) connectivity. We hypothesized that the interaction of large-scale RSNs is differently affected in patients with right- and left-MTLE with HS compared to controls. We aimed to determine and characterize these alterations through the analysis of 12 RSNs, functionally parceled in 70 regions of interest (ROIs), from resting-state functional-MRIs of 99 subjects (52 controls, 26 right- and 21 left-MTLE patients with HS). Image preprocessing and statistical analysis were performed using UF(2) C-toolbox, which provided ROI-wise results for intranetwork and internetwork connectivity. Intranetwork abnormalities were observed in the dorsal default mode network (DMN) in both groups of patients and in the posterior salience network in right-MTLE. Both groups showed abnormal correlation between the dorsal-DMN and the posterior salience, as well as between the dorsal-DMN and the executive-control network. Patients with left-MTLE also showed reduced correlation between the dorsal-DMN and visuospatial network and increased correlation between bilateral thalamus and the posterior salience network. The ipsilateral hippocampus stood out as a central area of abnormalities. Alterations on left-MTLE expressed a low cluster coefficient, whereas the altered connections on right-MTLE showed low cluster coefficient in the DMN but high in the posterior salience regions. Both right- and left-MTLE patients with HS have widespread abnormal interactions of large-scale brain networks; however, all parameters evaluated indicate that left-MTLE has a more intricate bihemispheric dysfunction compared to right-MTLE. Hum Brain Mapp 37:3137-3152, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by

  8. Coding of spatio-temporal attributes: the roles of age and enriched ...

    African Journals Online (AJOL)

    ... the study for assessment of spatio-temporal working memory in preclinical trials. Twenty six naive male long evan rats between the ages of 9-21 months, weighing between 200-400g were use for the study. They were divided into 3 groups: enriched young adults, non-enriched young adults and non-enriched older adults.

  9. Cracking the Time Code: Making Issues of Temporality in Curriculum Visible.

    Science.gov (United States)

    Woo, Joyceln Yen Yen

    This paper explores how looking at the lived time of secondary school students in Singapore has generated questions for curricular theory and practice. In-depth interviews, three of which are described, show the intersection of temporality and lived experience. Students are aware of rational, clock time, but seem to understand that there is an…

  10. The Role of Short Term Synaptic Plasticity in Temporal Coding of Neuronal Networks

    Science.gov (United States)

    Chandrasekaran, Lakshmi

    2008-01-01

    Short term synaptic plasticity is a phenomenon which is commonly found in the central nervous system. It could contribute to functions of signal processing namely, temporal integration and coincidence detection by modulating the input synaptic strength. This dissertation has two parts. First, we study the effects of short term synaptic plasticity…

  11. Assessing signal-driven mechanism in neonates: brain responses to temporally and spectrally different sounds

    Directory of Open Access Journals (Sweden)

    Yasuyo eMinagawa-Kawai

    2011-06-01

    Full Text Available Past studies have found that in adults that acoustic properties of sound signals (such as fast vs. slow temporal features differentially activate the left and right hemispheres, and some have hypothesized that left-lateralization for speech processing may follow from left-lateralization to rapidly changing signals. Here, we tested whether newborns’ brains show some evidence of signal-specific lateralization responses using near-infrared spectroscopy (NIRS and auditory stimuli that elicits lateralized responses in adults, composed of segments that vary in duration and spectral diversity. We found significantly greater bilateral responses of oxygenated hemoglobin (oxy-Hb in the temporal areas for stimuli with a minimum segment duration of 21 ms, than stimuli with a minimum segment duration of 667 ms. However, we found no evidence for hemispheric asymmetries dependent on the stimulus characteristics. We hypothesize that acoustic-based functional brain asymmetries may develop throughout early infancy, and discuss their possible relationship with brain asymmetries for language.

  12. New neurons in aging brains: molecular control by small non-coding RNAs

    Directory of Open Access Journals (Sweden)

    Marijn eSchouten

    2012-02-01

    Full Text Available Adult neurogenesis is a process that continues in the adult and also aging brain. It generates functional neurons from neural stem cells present in specific brain regions. This phenomenon is largely confined to two main regions: the subventricular zone of the lateral ventricle, and the subgranular zone of the dentate gyrus, in the hippocampus. With age, the hippocampus and particularly the dentate gyrus are affected. For instance, adult neurogenesis is decreased with aging, in both the number of proliferating cells as well as their neuronal differentiation, while in parallel an age-associated decline in cognitive performance is often seen. Surprisingly, the synaptogenic potential of adult-born neurons appears unaffected by aging. Therefore, although proliferation, differentiation, survival and synaptogenesis of adult-born new neurons in the dentate gyrus are closely related to each other, they appear differentially regulated with aging. In this review we discuss the crucial role of a novel class of recently discovered regulators of gene expression, i.e. the small non-coding RNAs, in the development of adult neurogenesis from neural stem cells to functionally integrated neurons. In particular, a subgroup of the small non-coding RNAs, the microRNAs, fine-tune many events during adult neurogenesis progression. Moreover, multiple small non-coding RNAs are differentially expressed in the aged hippocampus. This makes small non-coding RNAs appealing candidates to orchestrate, and possibly correct or prevent, the functional alterations in adult neurogenesis and cognition associated with aging. Finally, we briefly summarize observations that link changes in circulating levels of steroid hormones with alterations in adult neurogenesis and subsequent vulnerability to psychopathology in advanced age, and discuss a possible role of microRNAs in stress-associated alterations in adult neurogenesis during aging.

  13. MRI-based brain structure volumes in temporal lobe epilepsy patients and their unaffected siblings: a preliminary study.

    LENUS (Irish Health Repository)

    Scanlon, Cathy

    2013-01-01

    Investigating the heritability of brain structure may be useful in simplifying complicated genetic studies in temporal lobe epilepsy (TLE). A preliminary study is presented to determine if volume deficits of candidate brain structures present at a higher rate in unaffected siblings than controls subjects.

  14. Unsupervised clustering with spiking neurons by sparse temporal coding and multi-layer RBF networks

    NARCIS (Netherlands)

    S.M. Bohte (Sander); J.A. La Poutré (Han); J.N. Kok (Joost)

    2000-01-01

    textabstractWe demonstrate that spiking neural networks encoding information in spike times are capable of computing and learning clusters from realistic data. We show how a spiking neural network based on spike-time coding and Hebbian learning can successfully perform unsupervised clustering on

  15. Long-term music training tunes how the brain temporally binds signals from multiple senses.

    Science.gov (United States)

    Lee, Hweeling; Noppeney, Uta

    2011-12-20

    Practicing a musical instrument is a rich multisensory experience involving the integration of visual, auditory, and tactile inputs with motor responses. This combined psychophysics-fMRI study used the musician's brain to investigate how sensory-motor experience molds temporal binding of auditory and visual signals. Behaviorally, musicians exhibited a narrower temporal integration window than nonmusicians for music but not for speech. At the neural level, musicians showed increased audiovisual asynchrony responses and effective connectivity selectively for music in a superior temporal sulcus-premotor-cerebellar circuitry. Critically, the premotor asynchrony effects predicted musicians' perceptual sensitivity to audiovisual asynchrony. Our results suggest that piano practicing fine tunes an internal forward model mapping from action plans of piano playing onto visible finger movements and sounds. This internal forward model furnishes more precise estimates of the relative audiovisual timings and hence, stronger prediction error signals specifically for asynchronous music in a premotor-cerebellar circuitry. Our findings show intimate links between action production and audiovisual temporal binding in perception.

  16. Contrasting Effects of Vocabulary Knowledge on Temporal and Parietal Brain Structure across Lifespan

    Science.gov (United States)

    Richardson, Fiona M.; Thomas, Michael S. C.; Filippi, Roberto; Harth, Helen; Price, Cathy J.

    2010-01-01

    Using behavioral, structural, and functional imaging techniques, we demonstrate contrasting effects of vocabulary knowledge on temporal and parietal brain structure in 47 healthy volunteers who ranged in age from 7 to 73 years. In the left posterior supramarginal gyrus, vocabulary knowledge was positively correlated with gray matter density in teenagers but not adults. This region was not activated during auditory or visual sentence processing, and activation was unrelated to vocabulary skills. Its gray matter density may reflect the use of an explicit learning strategy that links new words to lexical or conceptual equivalents, as used in formal education and second language acquisition. By contrast, in left posterior temporal regions, gray matter as well as auditory and visual sentence activation correlated with vocabulary knowledge throughout lifespan. We propose that these effects reflect the acquisition of vocabulary through context, when new words are learnt within the context of semantically and syntactically related words. PMID:19366285

  17. Contrasting effects of vocabulary knowledge on temporal and parietal brain structure across lifespan.

    Science.gov (United States)

    Richardson, Fiona M; Thomas, Michael S C; Filippi, Roberto; Harth, Helen; Price, Cathy J

    2010-05-01

    Using behavioral, structural, and functional imaging techniques, we demonstrate contrasting effects of vocabulary knowledge on temporal and parietal brain structure in 47 healthy volunteers who ranged in age from 7 to 73 years. In the left posterior supramarginal gyrus, vocabulary knowledge was positively correlated with gray matter density in teenagers but not adults. This region was not activated during auditory or visual sentence processing, and activation was unrelated to vocabulary skills. Its gray matter density may reflect the use of an explicit learning strategy that links new words to lexical or conceptual equivalents, as used in formal education and second language acquisition. By contrast, in left posterior temporal regions, gray matter as well as auditory and visual sentence activation correlated with vocabulary knowledge throughout lifespan. We propose that these effects reflect the acquisition of vocabulary through context, when new words are learnt within the context of semantically and syntactically related words.

  18. Reconstructing Generalized Logical Networks of Transcriptional Regulation in Mouse Brain from Temporal Gene Expression Data

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mingzhou (Joe) [New Mexico State University, Las Cruces; Lewis, Chris K. [New Mexico State University, Las Cruces; Lance, Eric [New Mexico State University, Las Cruces; Chesler, Elissa J [ORNL; Kirova, Roumyana [Bristol-Myers Squibb Pharmaceutical Research & Development, NJ; Langston, Michael A [University of Tennessee, Knoxville (UTK); Bergeson, Susan [Texas Tech University, Lubbock

    2009-01-01

    The problem of reconstructing generalized logical networks to account for temporal dependencies among genes and environmental stimuli from high-throughput transcriptomic data is addressed. A network reconstruction algorithm was developed that uses the statistical significance as a criterion for network selection to avoid false-positive interactions arising from pure chance. Using temporal gene expression data collected from the brains of alcohol-treated mice in an analysis of the molecular response to alcohol, this algorithm identified genes from a major neuronal pathway as putative components of the alcohol response mechanism. Three of these genes have known associations with alcohol in the literature. Several other potentially relevant genes, highlighted and agreeing with independent results from literature mining, may play a role in the response to alcohol. Additional, previously-unknown gene interactions were discovered that, subject to biological verification, may offer new clues in the search for the elusive molecular mechanisms of alcoholism.

  19. Temporal Coding of Periodicity Pitch in the Auditory System: An Overview

    Directory of Open Access Journals (Sweden)

    Peter Cariani

    1999-01-01

    Population-wide inter-spike interval distributions are constructed by summing together intervals from the observed responses of many single Type I auditory nerve fibers. Features in such distributions correspond closely with pitches that are heard by human listeners. The most common all-order interval present in the auditory nerve array almost invariably corresponds to the pitch frequency, whereas the relative fraction of pitchrelated intervals amongst all others qualitatively corresponds to the strength of the pitch. Consequently, many diverse aspects of pitch perception are explained in terms of such temporal representations. Similar stimulus-driven temporal discharge patterns are observed in major neuronal populations of the cochlear nucleus. Population-interval distributions constitute an alternative time-domain strategy for representing sensory information that complements spatially organized sensory maps. Similar autocorrelation-like representations are possible in other sensory systems, in which neural discharges are time-locked to stimulus waveforms.

  20. Brain-responsive neurostimulation in patients with medically intractable mesial temporal lobe epilepsy.

    Science.gov (United States)

    Geller, Eric B; Skarpaas, Tara L; Gross, Robert E; Goodman, Robert R; Barkley, Gregory L; Bazil, Carl W; Berg, Michael J; Bergey, Gregory K; Cash, Sydney S; Cole, Andrew J; Duckrow, Robert B; Edwards, Jonathan C; Eisenschenk, Stephan; Fessler, James; Fountain, Nathan B; Goldman, Alicia M; Gwinn, Ryder P; Heck, Christianne; Herekar, Aamar; Hirsch, Lawrence J; Jobst, Barbara C; King-Stephens, David; Labar, Douglas R; Leiphart, James W; Marsh, W Richard; Meador, Kimford J; Mizrahi, Eli M; Murro, Anthony M; Nair, Dileep R; Noe, Katherine H; Park, Yong D; Rutecki, Paul A; Salanova, Vicenta; Sheth, Raj D; Shields, Donald C; Skidmore, Christopher; Smith, Michael C; Spencer, David C; Srinivasan, Shraddha; Tatum, William; Van Ness, Paul C; Vossler, David G; Wharen, Robert E; Worrell, Gregory A; Yoshor, Daniel; Zimmerman, Richard S; Cicora, Kathy; Sun, Felice T; Morrell, Martha J

    2017-06-01

    Evaluate the seizure-reduction response and safety of mesial temporal lobe (MTL) brain-responsive stimulation in adults with medically intractable partial-onset seizures of mesial temporal lobe origin. Subjects with mesial temporal lobe epilepsy (MTLE) were identified from prospective clinical trials of a brain-responsive neurostimulator (RNS System, NeuroPace). The seizure reduction over years 2-6 postimplantation was calculated by assessing the seizure frequency compared to a preimplantation baseline. Safety was assessed based on reported adverse events. There were 111 subjects with MTLE; 72% of subjects had bilateral MTL onsets and 28% had unilateral onsets. Subjects had one to four leads placed; only two leads could be connected to the device. Seventy-six subjects had depth leads only, 29 had both depth and strip leads, and 6 had only strip leads. The mean follow-up was 6.1 ± (standard deviation) 2.2 years. The median percent seizure reduction was 70% (last observation carried forward). Twenty-nine percent of subjects experienced at least one seizure-free period of 6 months or longer, and 15% experienced at least one seizure-free period of 1 year or longer. There was no difference in seizure reduction in subjects with and without mesial temporal sclerosis (MTS), bilateral MTL onsets, prior resection, prior intracranial monitoring, and prior vagus nerve stimulation. In addition, seizure reduction was not dependent on the location of depth leads relative to the hippocampus. The most frequent serious device-related adverse event was soft tissue implant-site infection (overall rate, including events categorized as device-related, uncertain, or not device-related: 0.03 per implant year, which is not greater than with other neurostimulation devices). Brain-responsive stimulation represents a safe and effective treatment option for patients with medically intractable epilepsy, including patients with unilateral or bilateral MTLE who are not candidates for

  1. Creative cognition and the brain: dissociations between frontal, parietal-temporal and basal ganglia groups.

    Science.gov (United States)

    Abraham, Anna; Beudt, Susan; Ott, Derek V M; Yves von Cramon, D

    2012-10-30

    The objective of the study was to investigate creativity in relation to brain function by assessing creative thinking in various neurological populations. Several measures were employed to assess different facets of creative thinking in clinical groups with frontal lobe, basal ganglia or parietal-temporal lesions relative to matched healthy control participants. The frontal group was subdivided into frontolateral, frontopolar and frontal-extensive groups. Hierarchical regression analyses were employed to assess the significance levels associated with the effects after accounting for IQ differences between the groups. Findings were only considered noteworthy if they at least suggested the presence of a strong trend and were accompanied by medium to large effect sizes. The parietal-temporal and frontolateral groups revealed poorer overall performance with the former demonstrating problems with fluency related measures, whereas the latter were also less proficient at producing original responses. In contrast, the basal ganglia and frontopolar groups demonstrated superior performance in the ability to overcome the constraints imposed by salient semantic distractors when generating creative responses. In summary, the dissociations in the findings reveal the selective involvement of different brain regions in diverse aspects of creativity. Lesion location posed selective limitations on the ability to generate original responses in different contexts, but not on the ability to generate relevant responses, which was compromised in most patient groups. The noteworthy findings from this exploratory study of enhanced performance in specific aspects of creative cognition following brain damage are discussed with reference to the generic idea that superior creative ability can result from altered brain function. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Comparing CAT12 and VBM8 for Detecting Brain Morphological Abnormalities in Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Farnaz Farokhian

    2017-08-01

    Full Text Available The identification of the brain morphological alterations that play important roles in neurodegenerative/neurological diseases will contribute to our understanding of the causes of these diseases. Various automated software programs are designed to provide an automatic framework to detect brain morphological changes in structural magnetic resonance imaging (MRI data. A voxel-based morphometry (VBM analysis can also be used for the detection of brain volumetric abnormalities. Here, we compared gray matter (GM and white matter (WM abnormality results obtained by a VBM analysis using the Computational Anatomy Toolbox (CAT12 via the current version of Statistical Parametric Mapping software (SPM12 with the results obtained by a VBM analysis using the VBM8 toolbox implemented in the older software SPM8, in adult temporal lobe epilepsy (TLE patients with (n = 51 and without (n = 57 hippocampus sclerosis (HS, compared to healthy adult controls (n = 28. The VBM analysis using CAT12 showed that compared to the healthy controls, significant GM and WM reductions were located in ipsilateral mesial temporal lobes in the TLE-HS patients, and slight GM amygdala swelling was present in the right TLE-no patients (n = 27. In contrast, the VBM analysis via the VBM8 toolbox showed significant GM and WM reductions only in the left TLE-HS patients (n = 25 compared to the healthy controls. Our findings thus demonstrate that compared to VBM8, a VBM analysis using CAT12 provides a more accurate volumetric analysis of the brain regions in TLE. Our results further indicate that a VBM analysis using CAT12 is more robust and accurate against volumetric alterations than the VBM8 toolbox.

  3. The temporal structures and functional significance of scale-free brain activity.

    Science.gov (United States)

    He, Biyu J; Zempel, John M; Snyder, Abraham Z; Raichle, Marcus E

    2010-05-13

    Scale-free dynamics, with a power spectrum following P proportional to f(-beta), are an intrinsic feature of many complex processes in nature. In neural systems, scale-free activity is often neglected in electrophysiological research. Here, we investigate scale-free dynamics in human brain and show that it contains extensive nested frequencies, with the phase of lower frequencies modulating the amplitude of higher frequencies in an upward progression across the frequency spectrum. The functional significance of scale-free brain activity is indicated by task performance modulation and regional variation, with beta being larger in default network and visual cortex and smaller in hippocampus and cerebellum. The precise patterns of nested frequencies in the brain differ from other scale-free dynamics in nature, such as earth seismic waves and stock market fluctuations, suggesting system-specific generative mechanisms. Our findings reveal robust temporal structures and behavioral significance of scale-free brain activity and should motivate future study on its physiological mechanisms and cognitive implications. Copyright 2010 Elsevier Inc. All rights reserved.

  4. Speech rhythms and multiplexed oscillatory sensory coding in the human brain.

    Directory of Open Access Journals (Sweden)

    Joachim Gross

    2013-12-01

    Full Text Available Cortical oscillations are likely candidates for segmentation and coding of continuous speech. Here, we monitored continuous speech processing with magnetoencephalography (MEG to unravel the principles of speech segmentation and coding. We demonstrate that speech entrains the phase of low-frequency (delta, theta and the amplitude of high-frequency (gamma oscillations in the auditory cortex. Phase entrainment is stronger in the right and amplitude entrainment is stronger in the left auditory cortex. Furthermore, edges in the speech envelope phase reset auditory cortex oscillations thereby enhancing their entrainment to speech. This mechanism adapts to the changing physical features of the speech envelope and enables efficient, stimulus-specific speech sampling. Finally, we show that within the auditory cortex, coupling between delta, theta, and gamma oscillations increases following speech edges. Importantly, all couplings (i.e., brain-speech and also within the cortex attenuate for backward-presented speech, suggesting top-down control. We conclude that segmentation and coding of speech relies on a nested hierarchy of entrained cortical oscillations.

  5. PROGRANULIN MUTATIONS AFFECTS BRAIN OSCILLATORY ACTIVITY IN FRONTO-TEMPORAL DEMENTIA

    Directory of Open Access Journals (Sweden)

    Davide Vito Moretti

    2016-02-01

    Full Text Available Background: mild cognitive impairment (MCI is a clinical stage indicating a prodromal phase of dementia. This practical concept could be used also for fronto-temporal dementia (FTD. Progranulin (PGRN has been recently recognized as a useful diagnostic biomarker for fronto-temporal lobe degeneration (FTLD due to GRN null mutations. Electroencephalography (EEG is a reliable tool in detecting brain networks changes. The working hypothesis of the present study is that EEG oscillations could detect different modifications among FTLD stages (FTD-MCI versus overt FTD as well as differences between GRN mutation carriers versus non carriers in patients with overt FTD. Methods: EEG in all patients and PGRN dosage in patients with a clear FTD were detected. The cognitive state has been investigated through mini mental state examination (MMSE. Results: MCI-FTD showed a significant lower spectral power in both alpha and theta oscillations as compared to overt FTD. GRN mutations carriers affected by FTLD show an increase in high alpha and decrease in theta oscillations as compared to non-carriers.Conclusion: EEG frequency rhythms are sensible to different stage of FTD and could detect changes in brain oscillatory activity affected by GRN mutations

  6. Hippocampal deep brain stimulation in nonlesional refractory mesial temporal lobe epilepsy.

    Science.gov (United States)

    Jin, Hongbo; Li, Wenling; Dong, Changzheng; Wu, Jiang; Zhao, Wenqing; Zhao, Zengyi; Ma, Li; Ma, Fa; Chen, Yao; Liu, Qianwei

    2016-04-01

    To evaluate the efficacy of chronic continuous hippocampal deep brain stimulation (DBS) in nonlesional refractory mesial temporal lobe epilepsy. Three adult patients with medically intractable epilepsy treated with hippocampal DBS were studied. Two patients underwent invasive recordings with depth stereo-electroencephalography (SEEG) electrodes to localize ictal onset zone prior to implantation of DBS electrodes. All the patients with no lesion in brain magnetic resonance imaging (MRI) scan received bilateral implantation of DBS electrodes. Chronic continuous high-frequency hippocampal stimulation was applied during treatment. The number of seizures in each patient before and after stimulation was compared. Long-term hippocampal stimulation produced a median reduction in seizure frequency of 93%. Two out of these patients received unilateral activation of the electrodes and experienced a 95% and 92% reduction in seizure frequency after hippocampal DBS respectively. The last patient had bilateral electrode activation and had a seizure-frequency reduction of 91%. None of the patients had neuropsychological deterioration and showed side effects. Generalized tonic-clonic seizures disappeared completely after hippocampal DBS. Chronic continuous hippocampal DBS demonstrated a potential efficiency and safety in nonlesional refractory mesial temporal lobe epilepsy and might represent an effective therapeutic option for these patients. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  7. Temporal dynamics of musical emotions examined through intersubject synchrony of brain activity.

    Science.gov (United States)

    Trost, Wiebke; Frühholz, Sascha; Cochrane, Tom; Cojan, Yann; Vuilleumier, Patrik

    2015-12-01

    To study emotional reactions to music, it is important to consider the temporal dynamics of both affective responses and underlying brain activity. Here, we investigated emotions induced by music using functional magnetic resonance imaging (fMRI) with a data-driven approach based on intersubject correlations (ISC). This method allowed us to identify moments in the music that produced similar brain activity (i.e. synchrony) among listeners under relatively natural listening conditions. Continuous ratings of subjective pleasantness and arousal elicited by the music were also obtained for the music outside of the scanner. Our results reveal synchronous activations in left amygdala, left insula and right caudate nucleus that were associated with higher arousal, whereas positive valence ratings correlated with decreases in amygdala and caudate activity. Additional analyses showed that synchronous amygdala responses were driven by energy-related features in the music such as root mean square and dissonance, while synchrony in insula was additionally sensitive to acoustic event density. Intersubject synchrony also occurred in the left nucleus accumbens, a region critically implicated in reward processing. Our study demonstrates the feasibility and usefulness of an approach based on ISC to explore the temporal dynamics of music perception and emotion in naturalistic conditions. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  8. Alcohol intoxication alters cognitive skills mediated by frontal and temporal brain regions.

    Science.gov (United States)

    Magrys, S A; Olmstead, M C

    2014-03-01

    Alcohol intoxication affects frontal and temporal brain areas and may functionally impair cognitive processes mediated by these regions. This study examined this hypothesis by testing the effects of alcohol on sustained attention, impulsivity, and verbal memory. Sober and placebo control groups were used to distinguish pharmacological from expectancy effects of alcohol. One hundred nine university students were assigned to an alcohol (low, medium, or high dose), placebo or sober group. Moderate and high doses of alcohol impaired all cognitive measures. A gender effect was revealed in that alcohol impaired sustained attention in males, but not females. Both sustained attention and verbal memory exhibited a U-shaped pattern, in that the medium-dose alcohol group showed the greatest impairment. This study adds to knowledge about the effects of alcohol intoxication on frontally- and temporally-mediated cognitive function. These findings have specific relevance for heavy-drinking undergraduate populations, particularly in light of the fact that repeated alcohol administration produces persistent changes in brain neurocircuitry. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Spatio-temporal analysis of brain electrical activity in epilepsy based on cellular nonlinear networks

    Science.gov (United States)

    Gollas, Frank; Tetzlaff, Ronald

    2009-05-01

    Epilepsy is the most common chronic disorder of the nervous system. Generally, epileptic seizures appear without foregoing sign or warning. The problem of detecting a possible pre-seizure state in epilepsy from EEG signals has been addressed by many authors over the past decades. Different approaches of time series analysis of brain electrical activity already are providing valuable insights into the underlying complex dynamics. But the main goal the identification of an impending epileptic seizure with a sufficient specificity and reliability, has not been achieved up to now. An algorithm for a reliable, automated prediction of epileptic seizures would enable the realization of implantable seizure warning devices, which could provide valuable information to the patient and time/event specific drug delivery or possibly a direct electrical nerve stimulation. Cellular Nonlinear Networks (CNN) are promising candidates for future seizure warning devices. CNN are characterized by local couplings of comparatively simple dynamical systems. With this property these networks are well suited to be realized as highly parallel, analog computer chips. Today available CNN hardware realizations exhibit a processing speed in the range of TeraOps combined with low power consumption. In this contribution new algorithms based on the spatio-temporal dynamics of CNN are considered in order to analyze intracranial EEG signals and thus taking into account mutual dependencies between neighboring regions of the brain. In an identification procedure Reaction-Diffusion CNN (RD-CNN) are determined for short segments of brain electrical activity, by means of a supervised parameter optimization. RD-CNN are deduced from Reaction-Diffusion Systems, which usually are applied to investigate complex phenomena like nonlinear wave propagation or pattern formation. The Local Activity Theory provides a necessary condition for emergent behavior in RD-CNN. In comparison linear spatio-temporal

  10. From Winner-Takes-All to Winners-Share-All: Exploiting the Information Capacity in Temporal Codes.

    Science.gov (United States)

    Payvand, Melika; Theogarajan, Luke

    2017-12-08

    In this letter, we have implemented and compared two neural coding algorithms in the networks of spiking neurons: Winner-takes-all (WTA) and winners-share-all (WSA). Winners-Share-All exploits the code space provided by the temporal code by training a different combination of [Formula: see text] out of [Formula: see text] neurons to fire together in response to different patterns, while WTA uses a one-hot-coding to respond to distinguished patterns. Using WSA, the maximum value of [Formula: see text] in order to maximize information capacity using [Formula: see text] output neurons was theoretically determined and utilized. A small proof-of-concept classification problem was applied to a spiking neural network using both algorithms to classify 14 letters of English alphabet with an image size of 15 [Formula: see text] 15 pixels. For both schemes, a modified spike-timing-dependent-plasticity (STDP) learning rule has been used to train the spiking neurons in an unsupervised fashion. The performance and the number of neurons required to perform this computation are compared between the two algorithms. We show that by tolerating a small drop in performance accuracy (84% in WSA versus 91% in WTA), we are able to reduce the number of output neurons by more than a factor of two. We show how the reduction in the number of neurons will increase as the number of patterns increases. The reduction in the number of output neurons would then proportionally reduce the number of training parameters, which requires less memory and hence speeds up the computation, and in the case of neuromorphic implementation on silicon, would take up much less area.

  11. Reconstructing Generalized Logical Networks of Transcriptional Regulation in Mouse Brain from Temporal Gene Expression Data

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    Lodowski Kerrie H

    2009-01-01

    Full Text Available Gene expression time course data can be used not only to detect differentially expressed genes but also to find temporal associations among genes. The problem of reconstructing generalized logical networks to account for temporal dependencies among genes and environmental stimuli from transcriptomic data is addressed. A network reconstruction algorithm was developed that uses statistical significance as a criterion for network selection to avoid false-positive interactions arising from pure chance. The multinomial hypothesis testing-based network reconstruction allows for explicit specification of the false-positive rate, unique from all extant network inference algorithms. The method is superior to dynamic Bayesian network modeling in a simulation study. Temporal gene expression data from the brains of alcohol-treated mice in an analysis of the molecular response to alcohol are used for modeling. Genes from major neuronal pathways are identified as putative components of the alcohol response mechanism. Nine of these genes have associations with alcohol reported in literature. Several other potentially relevant genes, compatible with independent results from literature mining, may play a role in the response to alcohol. Additional, previously unknown gene interactions were discovered that, subject to biological verification, may offer new clues in the search for the elusive molecular mechanisms of alcoholism.

  12. Temporal Scalability through Adaptive -Band Filter Banks for Robust H.264/MPEG-4 AVC Video Coding

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    Pau G

    2006-01-01

    Full Text Available This paper presents different structures that use adaptive -band hierarchical filter banks for temporal scalability. Open-loop and closed-loop configurations are introduced and illustrated using existing video codecs. In particular, it is shown that the H.264/MPEG-4 AVC codec allows us to introduce scalability by frame shuffling operations, thus keeping backward compatibility with the standard. The large set of shuffling patterns introduced here can be exploited to adapt the encoding process to the video content features, as well as to the user equipment and transmission channel characteristics. Furthermore, simulation results show that this scalability is obtained with no degradation in terms of subjective and objective quality in error-free environments, while in error-prone channels the scalable versions provide increased robustness.

  13. The temporal-spatial encoding of acupuncture effects in the brain

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    Yuan Kai

    2011-03-01

    Full Text Available Abstract Background Functional acupoint specificity is crucial to the clinical efficacy of acupuncture treatment, such as pain relief. Whether acupuncture needling at a peripheral acupoint produces distinct patterns of brain responses remains controversial. Results This fMRI study employed the complex network analysis (CNA to test the hypothesis that acupuncture stimulation at an acupoint correspondingly induced activity changes in one or more intrinsic or resting-state brain networks. Built upon the sustained effect of acupuncture and its time-varying characteristics, we constructed a dynamic encoding system with the hub anchored at the posterior cingulate cortex and precuneus (PCC/pC. We found that needling at two visual acupoints (GB37 and BL60 and a non-visual acupoint (KI8 induced a spatially converging brain response, which overlapped at the PCC/pC. We also found distinct neural modulations during and after acupoint stimulation. During this period, the PCC/pC interacted with a visual resting-state network in different patterns. Furthermore, there was a delayed functional correspondence between the intrinsic visual network and manipulation over the visual acupoints (i.e., GB37 or BL60, but not the non-visual acupoint (KI8 via the PCC/pC, implicating a specific temporal-spatial encoding/decoding mechanism underlying the post-effect of acupuncture. Conclusions This study provided an integrated view exploring the functional specificity of acupuncture in which both the needling sensation and the following neural cascades may contribute to the overall effect of acupuncture through dynamic reconfiguration of complex neural networks. fMRI, acupoints, posterior cingulate cortex, precuneus, temporal-spatial encoding, resting-state networks

  14. Molecular characterization and temporal expression profiling of presenilins in the developing porcine brain

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    Fredholm Merete

    2007-09-01

    Full Text Available Abstract Background The transmembrane presenilin (PSEN proteins, PSEN1 and PSEN2, have been proposed to be the catalytic components of the γ-secretase protein complex, which is an intramembranous multimeric protease involved in development, cell regulatory processes, and neurodegeneration in Alzheimer's disease. Here we describe the sequencing, chromosomal mapping, and polymorphism analysis of PSEN1 and PSEN2 in the domestic pig (Sus scrofa domesticus. Results The porcine presenilin proteins showed a high degree of homology over their entire sequences to the PSENs from mouse, bovine, and human. PSEN1 and PSEN2 transcription was examined during prenatal development of the brain stem, hippocampus, cortex, basal ganglia, and cerebellum at embryonic days 60, 80, 100, and 114, which revealed distinct temporal- and tissue-specific expression profiles. Furthermore, immunohistochemical analysis of PSEN1 and PSEN2 showed similar localization of the proteins predominantly in neuronal cells in all examined brain areas. Conclusion The data provide evidence for structural and functional conservation of PSENs in mammalian lineages, and may suggest that the high sequence similarity and colocalization of PSEN1 and PSEN2 in brain tissue reflect a certain degree of functional redundancy. The data show that pigs may provide a new animal model for detailed analysis of the developmental functions of the PSENs.

  15. A temporal predictive code for voice motor control: Evidence from ERP and behavioral responses to pitch-shifted auditory feedback.

    Science.gov (United States)

    Behroozmand, Roozbeh; Sangtian, Stacey; Korzyukov, Oleg; Larson, Charles R

    2016-04-01

    The predictive coding model suggests that voice motor control is regulated by a process in which the mismatch (error) between feedforward predictions and sensory feedback is detected and used to correct vocal motor behavior. In this study, we investigated how predictions about timing of pitch perturbations in voice auditory feedback would modulate ERP and behavioral responses during vocal production. We designed six counterbalanced blocks in which a +100 cents pitch-shift stimulus perturbed voice auditory feedback during vowel sound vocalizations. In three blocks, there was a fixed delay (500, 750 or 1000 ms) between voice and pitch-shift stimulus onset (predictable), whereas in the other three blocks, stimulus onset delay was randomized between 500, 750 and 1000 ms (unpredictable). We found that subjects produced compensatory (opposing) vocal responses that started at 80 ms after the onset of the unpredictable stimuli. However, for predictable stimuli, subjects initiated vocal responses at 20 ms before and followed the direction of pitch shifts in voice feedback. Analysis of ERPs showed that the amplitudes of the N1 and P2 components were significantly reduced in response to predictable compared with unpredictable stimuli. These findings indicate that predictions about temporal features of sensory feedback can modulate vocal motor behavior. In the context of the predictive coding model, temporally-predictable stimuli are learned and reinforced by the internal feedforward system, and as indexed by the ERP suppression, the sensory feedback contribution is reduced for their processing. These findings provide new insights into the neural mechanisms of vocal production and motor control. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Multiplexing stimulus information through rate and temporal codes in primate somatosensory cortex.

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    Michael A Harvey

    Full Text Available Our ability to perceive and discriminate textures relies on the transduction and processing of complex, high-frequency vibrations elicited in the fingertip as it is scanned across a surface. How naturalistic vibrations, and by extension texture, are encoded in the responses of neurons in primary somatosensory cortex (S1 is unknown. Combining single unit recordings in awake macaques and perceptual judgments obtained from human subjects, we show that vibratory amplitude is encoded in the strength of the response evoked in S1 neurons. In contrast, the frequency composition of the vibrations, up to 800 Hz, is not encoded in neuronal firing rates, but rather in the phase-locked responses of a subpopulation of neurons. Moreover, analysis of perceptual judgments suggests that spike timing not only conveys stimulus information but also shapes tactile perception. We conclude that information about the amplitude and frequency of natural vibrations is multiplexed at different time scales in S1, and encoded in the rate and temporal patterning of the response, respectively.

  17. Spatial and temporal variations in ammonia emissions – a freely accessible model code for Europe

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    C. A. Skjøth

    2011-06-01

    Full Text Available Deriving a parameterisation of ammonia emissions for use in chemistry-transport models (CTMs is a complex problem as the emission varies locally as a result of local climate and local agricultural management. In current CTMs such factors are generally not taken into account. This paper demonstrates how local climate and local management can be accounted for in CTMs by applying a modular approach for deriving data as input to a dynamic ammonia emission model for Europe. Default data are obtained from information in the RAINS system, and it is demonstrated how this dynamic emission model based on these input data improves the NH3 calculations in a CTM model when the results are compared with calculations obtained by traditional methods in emission handling. It is also shown how input data can be modified over a specific target region resulting in even further improvement in performance over this domain. The model code and the obtained default values for the modelling experiments are available as supplementary information to this article for use by the modelling community on similar terms as the EMEP CTM model: the GPL licencse v3.

  18. Qualitatively different coding of symbolic and nonsymbolic numbers in the human brain.

    Science.gov (United States)

    Lyons, Ian M; Ansari, Daniel; Beilock, Sian L

    2015-02-01

    Are symbolic and nonsymbolic numbers coded differently in the brain? Neuronal data indicate that overlap in numerical tuning curves is a hallmark of the approximate, analogue nature of nonsymbolic number representation. Consequently, patterns of fMRI activity should be more correlated when the representational overlap between two numbers is relatively high. In bilateral intraparietal sulci (IPS), for nonsymbolic numbers, the pattern of voxelwise correlations between pairs of numbers mirrored the amount of overlap in their tuning curves under the assumption of approximate, analogue coding. In contrast, symbolic numbers showed a flat field of modest correlations more consistent with discrete, categorical representation (no systematic overlap between numbers). Directly correlating activity patterns for a given number across formats (e.g., the numeral "6" with six dots) showed no evidence of shared symbolic and nonsymbolic number-specific representations. Overall (univariate) activity in bilateral IPS was well fit by the log of the number being processed for both nonsymbolic and symbolic numbers. IPS activity is thus sensitive to numerosity regardless of format; however, the nature in which symbolic and nonsymbolic numbers are encoded is fundamentally different. © 2014 Wiley Periodicals, Inc.

  19. Coding of visual object features and feature conjunctions in the human brain.

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    Jasna Martinovic

    Full Text Available Object recognition is achieved through neural mechanisms reliant on the activity of distributed coordinated neural assemblies. In the initial steps of this process, an object's features are thought to be coded very rapidly in distinct neural assemblies. These features play different functional roles in the recognition process--while colour facilitates recognition, additional contours and edges delay it. Here, we selectively varied the amount and role of object features in an entry-level categorization paradigm and related them to the electrical activity of the human brain. We found that early synchronizations (approx. 100 ms increased quantitatively when more image features had to be coded, without reflecting their qualitative contribution to the recognition process. Later activity (approx. 200-400 ms was modulated by the representational role of object features. These findings demonstrate that although early synchronizations may be sufficient for relatively crude discrimination of objects in visual scenes, they cannot support entry-level categorization. This was subserved by later processes of object model selection, which utilized the representational value of object features such as colour or edges to select the appropriate model and achieve identification.

  20. Simulation of the BNCT of Brain Tumors Using MCNP Code: Beam Designing and Dose Evaluation

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    Fatemeh Sadat Rasouli

    2012-09-01

    Full Text Available Introduction BNCT is an effective method to destroy brain tumoral cells while sparing the healthy tissues. The recommended flux for epithermal neutrons is 109 n/cm2s, which has the most effectiveness on deep-seated tumors. In this paper, it is indicated that using D-T neutron source and optimizing of Beam Shaping Assembly (BSA leads to treating brain tumors in a reasonable time where all IAEA recommended criteria are met. Materials and Methods The proposed BSA based on a D-T neutron generator consists of a neutron multiplier system, moderators, reflector, and collimator. The simulated Snyder head phantom is used to evaluate dose profiles in tissues due to the irradiation of designed beam. Monte Carlo Code, MCNP-4C, was used in order to perform these calculations.   Results The neutron beam associated with the designed and optimized BSA has an adequate epithermal flux at the beam port and neutron and gamma contaminations are removed as much as possible. Moreover, it was showed that increasing J/Φ, as a measure of beam directionality, leads to improvement of beam performance and survival of healthy tissues surrounding the tumor. Conclusion According to the simulation results, the proposed system based on D-T neutron source, which is suitable for in-hospital installations, satisfies all in-air parameters. Moreover, depth-dose curves investigate proper performance of designed beam in tissues. The results are comparable with the performances of other facilities.

  1. Differential combinatorial coding of pheromones in two olfactory subsystems of the honey bee brain.

    Science.gov (United States)

    Carcaud, Julie; Giurfa, Martin; Sandoz, Jean-Christophe

    2015-03-11

    Neural coding of pheromones has been intensively studied in insects with a particular focus on sex pheromones. These studies favored the view that pheromone compounds are processed within specific antennal lobe glomeruli following a specialized labeled-line system. However, pheromones play crucial roles in an insect's life beyond sexual attraction, and some species use many different pheromones making such a labeled-line organization unrealistic. A combinatorial coding scheme, in which each component activates a set of broadly tuned units, appears more adapted in this case. However, this idea has not been tested thoroughly. We focused here on the honey bee Apis mellifera, a social insect that relies on a wide range of pheromones to ensure colony cohesion. Interestingly, the honey bee olfactory system harbors two central parallel pathways, whose functions remain largely unknown. Using optophysiological recordings of projection neurons, we compared the responses of these two pathways to 27 known honey bee pheromonal compounds emitted by the brood, the workers, and the queen. We show that while queen mandibular pheromone is processed by l-ALT (lateral antennal lobe tract) neurons and brood pheromone is mainly processed by m-ALT (median antennal lobe tract) neurons, worker pheromones induce redundant activity in both pathways. Moreover, all tested pheromonal compounds induce combinatorial activity from several AL glomeruli. These findings support the combinatorial coding scheme and suggest that higher-order brain centers reading out these combinatorial activity patterns may eventually classify olfactory signals according to their biological meaning. Copyright © 2015 the authors 0270-6474/15/354157-11$15.00/0.

  2. Temporal Fine-Structure Coding and Lateralized Speech Perception in Normal-Hearing and Hearing-Impaired Listeners

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    Gusztáv Lőcsei

    2016-08-01

    Full Text Available This study investigated the relationship between speech perception performance in spatially complex, lateralized listening scenarios and temporal fine-structure (TFS coding at low frequencies. Young normal-hearing (NH and two groups of elderly hearing-impaired (HI listeners with mild or moderate hearing loss above 1.5 kHz participated in the study. Speech reception thresholds (SRTs were estimated in the presence of either speech-shaped noise, two-, four-, or eight-talker babble played reversed, or a nonreversed two-talker masker. Target audibility was ensured by applying individualized linear gains to the stimuli, which were presented over headphones. The target and masker streams were lateralized to the same or to opposite sides of the head by introducing 0.7-ms interaural time differences between the ears. TFS coding was assessed by measuring frequency discrimination thresholds and interaural phase difference thresholds at 250 Hz. NH listeners had clearly better SRTs than the HI listeners. However, when maskers were spatially separated from the target, the amount of SRT benefit due to binaural unmasking differed only slightly between the groups. Neither the frequency discrimination threshold nor the interaural phase difference threshold tasks showed a correlation with the SRTs or with the amount of masking release due to binaural unmasking, respectively. The results suggest that, although HI listeners with normal hearing thresholds below 1.5 kHz experienced difficulties with speech understanding in spatially complex environments, these limitations were unrelated to TFS coding abilities and were only weakly associated with a reduction in binaural-unmasking benefit for spatially separated competing sources.

  3. Temporal Fine-Structure Coding and Lateralized Speech Perception in Normal-Hearing and Hearing-Impaired Listeners.

    Science.gov (United States)

    Lőcsei, Gusztáv; Pedersen, Julie H; Laugesen, Søren; Santurette, Sébastien; Dau, Torsten; MacDonald, Ewen N

    2016-09-05

    This study investigated the relationship between speech perception performance in spatially complex, lateralized listening scenarios and temporal fine-structure (TFS) coding at low frequencies. Young normal-hearing (NH) and two groups of elderly hearing-impaired (HI) listeners with mild or moderate hearing loss above 1.5 kHz participated in the study. Speech reception thresholds (SRTs) were estimated in the presence of either speech-shaped noise, two-, four-, or eight-talker babble played reversed, or a nonreversed two-talker masker. Target audibility was ensured by applying individualized linear gains to the stimuli, which were presented over headphones. The target and masker streams were lateralized to the same or to opposite sides of the head by introducing 0.7-ms interaural time differences between the ears. TFS coding was assessed by measuring frequency discrimination thresholds and interaural phase difference thresholds at 250 Hz. NH listeners had clearly better SRTs than the HI listeners. However, when maskers were spatially separated from the target, the amount of SRT benefit due to binaural unmasking differed only slightly between the groups. Neither the frequency discrimination threshold nor the interaural phase difference threshold tasks showed a correlation with the SRTs or with the amount of masking release due to binaural unmasking, respectively. The results suggest that, although HI listeners with normal hearing thresholds below 1.5 kHz experienced difficulties with speech understanding in spatially complex environments, these limitations were unrelated to TFS coding abilities and were only weakly associated with a reduction in binaural-unmasking benefit for spatially separated competing sources. © The Author(s) 2016.

  4. Decoding temporal structure in music and speech relies on shared brain resources but elicits different fine-scale spatial patterns.

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    Abrams, Daniel A; Bhatara, Anjali; Ryali, Srikanth; Balaban, Evan; Levitin, Daniel J; Menon, Vinod

    2011-07-01

    Music and speech are complex sound streams with hierarchical rules of temporal organization that become elaborated over time. Here, we use functional magnetic resonance imaging to measure brain activity patterns in 20 right-handed nonmusicians as they listened to natural and temporally reordered musical and speech stimuli matched for familiarity, emotion, and valence. Heart rate variability and mean respiration rates were simultaneously measured and were found not to differ between musical and speech stimuli. Although the same manipulation of temporal structure elicited brain activation level differences of similar magnitude for both music and speech stimuli, multivariate classification analysis revealed distinct spatial patterns of brain responses in the 2 domains. Distributed neuronal populations that included the inferior frontal cortex, the posterior and anterior superior and middle temporal gyri, and the auditory brainstem classified temporal structure manipulations in music and speech with significant levels of accuracy. While agreeing with previous findings that music and speech processing share neural substrates, this work shows that temporal structure in the 2 domains is encoded differently, highlighting a fundamental dissimilarity in how the same neural resources are deployed.

  5. Interictal brain SPECT in patients with medically refractory temporal lobe epilepsy; SPECT cerebral interictal em pacientes com epilepsia do lobo temporal de dificil controle

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    Andraus, Maria Emilia Cosenza

    2000-06-01

    The brain single photon emission computed tomography (SPECT) is s functional neuroimaging method that can detect localized changes in cerebral blood flow. The temporal lobe epilepsy (TLE) is the most common epileptic syndrome in adults, and more than 50% are medically refractory. The SPECT can contribute to investigation of epileptogenic focus and is one of the methods of pre-surgical evaluation of these patients. (author)

  6. Our Faces in the Dog's Brain: Functional Imaging Reveals Temporal Cortex Activation during Perception of Human Faces.

    Science.gov (United States)

    Cuaya, Laura V; Hernández-Pérez, Raúl; Concha, Luis

    2016-01-01

    Dogs have a rich social relationship with humans. One fundamental aspect of it is how dogs pay close attention to human faces in order to guide their behavior, for example, by recognizing their owner and his/her emotional state using visual cues. It is well known that humans have specific brain regions for the processing of other human faces, yet it is unclear how dogs' brains process human faces. For this reason, our study focuses on describing the brain correlates of perception of human faces in dogs using functional magnetic resonance imaging (fMRI). We trained seven domestic dogs to remain awake, still and unrestrained inside an MRI scanner. We used a visual stimulation paradigm with block design to compare activity elicited by human faces against everyday objects. Brain activity related to the perception of faces changed significantly in several brain regions, but mainly in the bilateral temporal cortex. The opposite contrast (i.e., everyday objects against human faces) showed no significant brain activity change. The temporal cortex is part of the ventral visual pathway, and our results are consistent with reports in other species like primates and sheep, that suggest a high degree of evolutionary conservation of this pathway for face processing. This study introduces the temporal cortex as candidate to process human faces, a pillar of social cognition in dogs.

  7. Our Faces in the Dog's Brain: Functional Imaging Reveals Temporal Cortex Activation during Perception of Human Faces.

    Directory of Open Access Journals (Sweden)

    Laura V Cuaya

    Full Text Available Dogs have a rich social relationship with humans. One fundamental aspect of it is how dogs pay close attention to human faces in order to guide their behavior, for example, by recognizing their owner and his/her emotional state using visual cues. It is well known that humans have specific brain regions for the processing of other human faces, yet it is unclear how dogs' brains process human faces. For this reason, our study focuses on describing the brain correlates of perception of human faces in dogs using functional magnetic resonance imaging (fMRI. We trained seven domestic dogs to remain awake, still and unrestrained inside an MRI scanner. We used a visual stimulation paradigm with block design to compare activity elicited by human faces against everyday objects. Brain activity related to the perception of faces changed significantly in several brain regions, but mainly in the bilateral temporal cortex. The opposite contrast (i.e., everyday objects against human faces showed no significant brain activity change. The temporal cortex is part of the ventral visual pathway, and our results are consistent with reports in other species like primates and sheep, that suggest a high degree of evolutionary conservation of this pathway for face processing. This study introduces the temporal cortex as candidate to process human faces, a pillar of social cognition in dogs.

  8. Brain SPECT in mesial temporal lobe epilepsy: comparison between visual analysis and SPM (Statistical Parametric Mapping)

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    Amorim, Barbara Juarez; Ramos, Celso Dario; Santos, Allan Oliveira dos; Lima, Mariana da Cunha Lopes de; Camargo, Edwaldo Eduardo; Etchebehere, Elba Cristina Sa de Camargo, E-mail: juarezbarbara@hotmail.co [State University of Campinas (UNICAMP), SP (Brazil). School of Medical Sciences. Dept. of Radiology; Min, Li Li; Cendes, Fernando [State University of Campinas (UNICAMP), SP (Brazil). School of Medical Sciences. Dept. of Neurology

    2010-04-15

    Objective: to compare the accuracy of SPM and visual analysis of brain SPECT in patients with mesial temporal lobe epilepsy (MTLE). Method: interictal and ictal SPECTs of 22 patients with MTLE were performed. Visual analysis were performed in interictal (VISUAL(inter)) and ictal (VISUAL(ictal/inter)) studies. SPM analysis consisted of comparing interictal (SPM(inter)) and ictal SPECTs (SPM(ictal)) of each patient to control group and by comparing perfusion of temporal lobes in ictal and interictal studies among themselves (SPM(ictal/inter)). Results: for detection of the epileptogenic focus, the sensitivities were as follows: VISUAL(inter)=68%; VISUAL(ictal/inter)=100%; SPM(inter)=45%; SPM(ictal)=64% and SPM(ictal/inter)=77%. SPM was able to detect more areas of hyperperfusion and hypoperfusion. Conclusion: SPM did not improve the sensitivity to detect epileptogenic focus. However, SPM detected different regions of hypoperfusion and hyperperfusion and is therefore a helpful tool for better understand pathophysiology of seizures in MTLE. (author)

  9. Brain-grounded theory of temporal and spatial design in architecture and the environment

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    Ando, Yoichi

    2016-01-01

    In this book, brain-grounded theory of temporal and spatial design in architecture and the environment is discussed. The author believes that it is a key to solving such global problems as environmental disorders and severe climate change as well as conflicts that are caused by the ill-conceived notion of “time is money”. There are three phases or aspects of a person’s life: the physical life, the spiritual or mental life, and the third stage of life, when a person moves from middle age into old age and can choose what he or she wishes to do instead of simply what must be done. This book describes the temporal design of the environment based on the theory of subjective preference, which could make it possible for an individual to realize a healthy life in all three phases. In his previously published work, the present author wrote that the theory of subjective preference has been established for the sound and visual fields based on neural evidence, and that subjective preference is an overall response o...

  10. Medial temporal lobe contributions to intra-item associative recognition memory in the aging brain.

    Science.gov (United States)

    Dalton, Marshall Axel; Tu, Sicong; Hornberger, Michael; Hodges, John Russel; Piguet, Olivier

    2013-01-01

    Aging is associated with a decline in episodic memory function. This is accompanied by degradation of and functional changes in the medial temporal lobe (MTL) which subserves mnemonic processing. To date no study has investigated age-related functional change in MTL substructures during specific episodic memory processes such as intra-item associative memory. The aim of this study was to characterize age-related change in the neural correlates of intra-item associative memory processing. Sixteen young and 10 older subjects participated in a compound word intra-item associative memory task comprising a measure of associative recognition memory and a measure of recognition memory. There was no difference in performance between groups on the associative memory measure but each group recruited different MTL regions while performing the task. The young group recruited the left anterior hippocampus and posterior parahippocampal gyrus whereas the older participants recruited the hippocampus bilaterally. In contrast, recognition memory was significantly worse in the older subjects. The left anterior hippocampus was recruited in the young group during successful recognition memory whereas the older group recruited a more posterior region of the left hippocampus and showed a more bilateral activation of frontal brain regions than was observed in the young group. Our results suggest a reorganization of the neural correlates of intra-item associative memory in the aging brain.

  11. Medial temporal lobe contributions to intra-item associative recognition memory in the ageing brain

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    Marshall Axel Dalton

    2014-01-01

    Full Text Available Ageing is associated with a decline in episodic memory function. This is accompanied by degradation of and functional changes in the medial temporal lobe (MTL which subserves mnemonic processing. To date no study has investigated age related functional change in MTL substructures during specific episodic memory processes such as intra-item associative memory. The aim of this study was to characterise age related change in the neural correlates of intra-item associative memory processing. 16 young and 10 older subjects participated in a compound word intra-item associative memory task comprising a measure of associative recognition memory and a measure of recognition memory. There was no difference in performance between groups on the associative memory measure but each group recruited different MTL regions while performing the task. The young group recruited the left anterior hippocampus and posterior parahippocampal gyrus whereas the older participants recruited the hippocampus bilaterally. In contrast, recognition memory was significantly worse in the older subjects. The left anterior hippocampus was recruited in the young group during successful recognition memory whereas the older group recruited a more posterior region of the left hippocampus and showed a more bilateral activation of frontal brain regions than was observed in the young group. Our results suggest a reorganisation of the neural correlates of intra-item associative memory in the ageing brain.

  12. Memory rehabilitation and brain training for surgical temporal lobe epilepsy patients: a preliminary report.

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    Koorenhof, Loes; Baxendale, Sallie; Smith, Natalie; Thompson, Pam

    2012-04-01

    The short term impact of a memory rehabilitation programme on verbal memory test performance and subjective ratings of memory in everyday life was assessed in healthy controls and left temporal lobe epilepsy (LTLE) surgical patients. The intervention involved training in the use of external and internal memory support strategies. Half of the sample in addition undertook computerised brain training exercises as homework. LTLE patients were seen either before surgery or 3-6 months after their operation. Improvements in verbal memory were observed in both groups. An effect of brain training was recorded but this did not occur in a consistent direction. Subjective ratings of memory indicated improvements that were significant for the LTLE group but not the controls. Positive changes in the memory outcome measures were associated with improvements in mood. Pre-operative memory rehabilitation was not associated with better outcomes than post-operative intervention. Further research is needed to explore the persistence of the changes observed and to explore if pre-operative rehabilitation offsets post-operative memory decline. Copyright © 2011 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  13. Brain protective effect of dexmedetomidine on perioperative patients in temporal muscle sticking for moyamoya disease

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    Jun CHEN

    2014-06-01

    Full Text Available Objective To study the application of dexmedetomidine in patients undergoing temporal muscle sticking for moyamoya disease (MMD, and to discuss the possible mechanism of brain protection. Methods Sixty patients undergoing temporal muscle sticking operation were randomly divided into 2 groups: dexmedetomidine group (Group D, N = 30 and control group (Group S, N = 30, respectively receiving dexmedetomidine intravenous infusion (0.60 μ g/kg and the same dose of normal saline before anesthesia induction. In Group D, dexemdetomidine was administered continuously (intravenous pumping with the dose of 0.40 μg/(kg·h perioperatively, while the same dose of normal saline was administered in Group S. Heart rate (HR and mean arterial pressure (MAP were recorded at T0 (before administration, T1 (before tracheal intubation, T2 (1 min after intubation, T3 (at the moment of skin incision, T4 (before extubation and T5 (1 min after extubation respectively. Total amount of propofol, remifentanil and patients' recovery conditions after anesthesia were also recorded. Glutamine and malondialdehyde (MDA were measured and compared before and after operation. Results In group D, HR and MAP decreased significantly at T2-4 compared with T0 (P < 0.05, for all. Total amount of propofol, remifentanil in Group D was lower than that in Group S (P < 0.05, for all and the patients' recovery conditions in Group D after anesthesia was better than Group S (P = 0.000, for all, without occurence of shivering, cough and dysphoria (P < 0.05, for all. Glutamine and MDA increased after anesthesia compared with that before anesthesia in both 2 groups (P < 0.05, for all, however, it was higher in Group S than that in Group D (P < 0.05, for all. Conclusions Dexmedetomidine can provide stable hemodynamic condition during the anesthesia with patients undergoing temporal muscle sticking for moyamoya disease, and has a positive effect on improving both the outcome of the operation and

  14. Stimulating the Brain's Language Network: Syntactic Ambiguity Resolution after TMS to the Inferior Frontal Gyrus and Middle Temporal Gyrus

    NARCIS (Netherlands)

    Acheson, D.J.; Hagoort, P.

    2013-01-01

    The posterior middle temporal gyrus (MTG) and inferior frontal gyrus (IFG) are two critical nodes of the brain's language network. Previous neuroimaging evidence has supported a dissociation in language comprehension in which parts of the MTG are involved in the retrieval of lexical syntactic

  15. Premotor neural correlates of predictive motor timing for speech production and hand movement: evidence for a temporal predictive code in the motor system.

    Science.gov (United States)

    Johari, Karim; Behroozmand, Roozbeh

    2017-05-01

    The predictive coding model suggests that neural processing of sensory information is facilitated for temporally-predictable stimuli. This study investigated how temporal processing of visually-presented sensory cues modulates movement reaction time and neural activities in speech and hand motor systems. Event-related potentials (ERPs) were recorded in 13 subjects while they were visually-cued to prepare to produce a steady vocalization of a vowel sound or press a button in a randomized order, and to initiate the cued movement following the onset of a go signal on the screen. Experiment was conducted in two counterbalanced blocks in which the time interval between visual cue and go signal was temporally-predictable (fixed delay at 1000 ms) or unpredictable (variable between 1000 and 2000 ms). Results of the behavioral response analysis indicated that movement reaction time was significantly decreased for temporally-predictable stimuli in both speech and hand modalities. We identified premotor ERP activities with a left-lateralized parietal distribution for hand and a frontocentral distribution for speech that were significantly suppressed in response to temporally-predictable compared with unpredictable stimuli. The premotor ERPs were elicited approximately -100 ms before movement and were significantly correlated with speech and hand motor reaction times only in response to temporally-predictable stimuli. These findings suggest that the motor system establishes a predictive code to facilitate movement in response to temporally-predictable sensory stimuli. Our data suggest that the premotor ERP activities are robust neurophysiological biomarkers of such predictive coding mechanisms. These findings provide novel insights into the temporal processing mechanisms of speech and hand motor systems.

  16. Open chromatin profiling of human postmortem brain infers functional roles for non-coding schizophrenia loci.

    Science.gov (United States)

    Fullard, John F; Giambartolomei, Claudia; Hauberg, Mads E; Xu, Ke; Voloudakis, Georgios; Shao, Zhiping; Bare, Christopher; Dudley, Joel T; Mattheisen, Manuel; Robakis, Nikolaos K; Haroutunian, Vahram; Roussos, Panos

    2017-05-15

    Open chromatin provides access to DNA-binding proteins for the correct spatiotemporal regulation of gene expression. Mapping chromatin accessibility has been widely used to identify the location of cis regulatory elements (CREs) including promoters and enhancers. CREs show tissue- and cell-type specificity and disease-associated variants are often enriched for CREs in the tissues and cells that pertain to a given disease. To better understand the role of CREs in neuropsychiatric disorders we applied the Assay for Transposase Accessible Chromatin followed by sequencing (ATAC-seq) to neuronal and non-neuronal nuclei isolated from frozen postmortem human brain by fluorescence-activated nuclear sorting (FANS). Most of the identified open chromatin regions (OCRs) are differentially accessible between neurons and non-neurons, and show enrichment with known cell type markers, promoters and enhancers. Relative to those of non-neurons, neuronal OCRs are more evolutionarily conserved and are enriched in distal regulatory elements. Transcription factor (TF) footprinting analysis identifies differences in the regulome between neuronal and non-neuronal cells and ascribes putative functional roles to a number of non-coding schizophrenia (SCZ) risk variants. Among the identified variants is a Single Nucleotide Polymorphism (SNP) proximal to the gene encoding SNX19. In vitro experiments reveal that this SNP leads to an increase in transcriptional activity. As elevated expression of SNX19 has been associated with SCZ, our data provide evidence that the identified SNP contributes to disease. These results represent the first analysis of OCRs and TF-binding sites in distinct populations of postmortem human brain cells and further our understanding of the regulome and the impact of neuropsychiatric disease-associated genetic risk variants. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. The Mozart effect: distinctive aspects of the music--a clue to brain coding?

    Science.gov (United States)

    Hughes, J R; Fino, J J

    2000-04-01

    The goal of this study was to determine distinctive aspects of Mozart music that may explain the "Mozart Effect," specifically, the decrease in seizure activity. As many as 81 musical selections of Mozart, but also 67 of J.C. Bach, 67 of J.S. Bach, 39 of Chopin and 148 from 55 other composers were computer analyzed to quantify the music in search of any distinctive aspect and later to determine the degree to which a dominant periodicity could be found. Long-term periodicity (especially 10-60 sec, mean and median of 30 sec), was found often in Mozart music but also that of the two Bachs, significantly more often than the other composers and was especially absent in the control music that had no effect on epileptic activity in previous studies. Short-term periodicities were not significantly different between Mozart and the Bachs vs. the other composers. The conclusion is that one distinctive aspect of Mozart music is long-term periodicity that may well resonate within the cerebral cortex and also may be related to coding within the brain.

  18. Brain responses to regular and octave-scrambled melodies: A case of predictive-coding?

    Science.gov (United States)

    Globerson, Eitan; Granot, Roni; Tal, Idan; Harpaz, Yuval; Zeev-Wolf, Maor; Golstein, Abraham

    2017-03-01

    Melody recognition is an online process of evaluating incoming information and comparing this information to an existing internal corpus, thereby reducing prediction error. The predictive-coding model postulates top-down control on sensory processing accompanying reduction in prediction error. To investigate the relevancy of this model to melody processing, the current study examined early magnetoencephalogram (MEG) auditory responses to familiar and unfamiliar melodies in 25 participants. The familiar melodies followed and primed an octave-scrambled version of the same melody. The retrograde version of theses melodies served as the unfamiliar control condition. Octave-transposed melodies were included to examine the influence of pitch representation (pitch-height/pitch-chroma representation) on brain responses to melody recognition. Results demonstrate a reduction of the M100 auditory response to familiar, as compared with unfamiliar, melodies regardless of their form of presentation (condensed vs. octave-scrambled). This trend appeared to begin after the third tone of the melody. An additional behavioral study with the same melody corpus showed a similar trend-namely, a significant difference between familiarity rating for familiar and unfamiliar melodies, beginning with the third tone of the melody. These results may indicate a top-down inhibition of early auditory responses to melodies that is influenced by pitch representation. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. Volumetric analysis of medial temporal lobe structures in brain development from childhood to adolescence.

    Science.gov (United States)

    Hu, Shiyan; Pruessner, Jens C; Coupé, Pierrick; Collins, D Louis

    2013-07-01

    Puberty is an important stage of development as a child's sexual and physical characteristics mature because of hormonal changes. To better understand puberty-related effects on brain development, we investigated the magnetic resonance imaging (MRI) data of 306 subjects from 4 to 18 years of age. Subjects were grouped into before and during puberty groups according to their sexual maturity levels measured by the puberty scores. An appearance model-based automatic segmentation method with patch-based local refinement was employed to segment the MRI data and extract the volumes of medial temporal lobe (MTL) structures including the amygdala (AG), the hippocampus (HC), the entorhinal/perirhinal cortex (EPC), and the parahippocampal cortex (PHC). Our analysis showed age-related volumetric changes for the AG, HC, right EPC, and left PHC but only before puberty. After onset of puberty, these volumetric changes then correlate more with sexual maturity level, as measured by the puberty score. When normalized for brain volume, the volumes of the right HC decrease for boys; the volumes of the left HC increase for girls; and the volumes of the left and right PHC decrease for boys. These findings suggest that the rising levels of testosterone in boys and estrogen in girls might have opposite effects, especially for the HC and the PHC. Our findings on sex-specific and sexual maturity-related volumes may be useful in better understanding the MTL developmental differences and related learning, memory, and emotion differences between boys and girls during puberty. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Asymmetric projections of the arcuate fasciculus to the temporal cortex underlie lateralized language function in the human brain

    Science.gov (United States)

    Takaya, Shigetoshi; Kuperberg, Gina R.; Liu, Hesheng; Greve, Douglas N.; Makris, Nikos; Stufflebeam, Steven M.

    2015-01-01

    The arcuate fasciculus (AF) in the human brain has asymmetric structural properties. However, the topographic organization of the asymmetric AF projections to the cortex and its relevance to cortical function remain unclear. Here we mapped the posterior projections of the human AF in the inferior parietal and lateral temporal cortices using surface-based structural connectivity analysis based on diffusion MRI and investigated their hemispheric differences. We then performed the cross-modal comparison with functional connectivity based on resting-state functional MRI (fMRI) and task-related cortical activation based on fMRI using a semantic classification task of single words. Structural connectivity analysis showed that the left AF connecting to Broca's area predominantly projected in the lateral temporal cortex extending from the posterior superior temporal gyrus to the mid part of the superior temporal sulcus and the middle temporal gyrus, whereas the right AF connecting to the right homolog of Broca's area predominantly projected to the inferior parietal cortex extending from the mid part of the supramarginal gyrus to the anterior part of the angular gyrus. The left-lateralized projection regions of the AF in the left temporal cortex had asymmetric functional connectivity with Broca's area, indicating structure-function concordance through the AF. During the language task, left-lateralized cortical activation was observed. Among them, the brain responses in the temporal cortex and Broca's area that were connected through the left-lateralized AF pathway were specifically correlated across subjects. These results suggest that the human left AF, which structurally and functionally connects the mid temporal cortex and Broca's area in asymmetrical fashion, coordinates the cortical activity in these remote cortices during a semantic decision task. The unique feature of the left AF is discussed in the context of the human capacity for language. PMID:26441551

  1. Speech Coding in the Brain: Representation of Vowel Formants by Midbrain Neurons Tuned to Sound Fluctuations 1,2,3

    OpenAIRE

    Carney, Laurel H.; Li, Tianhao; McDonough, Joyce M.

    2015-01-01

    Abstract Current models for neural coding of vowels are typically based on linear descriptions of the auditory periphery, and fail at high sound levels and in background noise. These models rely on either auditory nerve discharge rates or phase locking to temporal fine structure. However, both discharge rates and phase locking saturate at moderate to high sound levels, and phase locking is degraded in the CNS at middle to high frequencies. The fact that speech intelligibility is robust over a...

  2. Neural network-based brain tissue segmentation in MR images using extracted features from intraframe coding in H.264

    Science.gov (United States)

    Jafari, Mehdi; Kasaei, Shohreh

    2012-01-01

    Automatic brain tissue segmentation is a crucial task in diagnosis and treatment of medical images. This paper presents a new algorithm to segment different brain tissues, such as white matter (WM), gray matter (GM), cerebral spinal fluid (CSF), background (BKG), and tumor tissues. The proposed technique uses the modified intraframe coding yielded from H.264/(AVC), for feature extraction. Extracted features are then imposed to an artificial back propagation neural network (BPN) classifier to assign each block to its appropriate class. Since the newest coding standard, H.264/AVC, has the highest compression ratio, it decreases the dimension of extracted features and thus yields to a more accurate classifier with low computational complexity. The performance of the BPN classifier is evaluated using the classification accuracy and computational complexity terms. The results show that the proposed technique is more robust and effective with low computational complexity compared to other recent works.

  3. Specific Regional and Age-Related Small Noncoding RNA Expression Patterns Within Superior Temporal Gyrus of Typical Human Brains Are Less Distinct in Autism Brains

    Science.gov (United States)

    Stamova, Boryana; Ander, Bradley P.; Barger, Nicole; Sharp, Frank R.

    2015-01-01

    Small noncoding RNAs play a critical role in regulating messenger RNA throughout brain development and when altered could have profound effects leading to disorders such as autism spectrum disorders (ASD). We assessed small noncoding RNAs, including microRNA and small nucleolar RNA, in superior temporal sulcus association cortex and primary auditory cortex in typical and ASD brains from early childhood to adulthood. Typical small noncoding RNA expression profiles were less distinct in ASD, both between regions and changes with age. Typical micro-RNA coexpression associations were absent in ASD brains. miR-132, miR-103, and miR-320 micro-RNAs were dysregulated in ASD and have previously been associated with autism spectrum disorders. These diminished region- and age-related micro-RNA expression profiles are in line with previously reported findings of attenuated messenger RNA and long noncoding RNA in ASD brain. This study demonstrates alterations in superior temporal sulcus in ASD, a region implicated in social impairment, and is the first to demonstrate molecular alterations in the primary auditory cortex. PMID:26350727

  4. Large scale functional brain networks underlying temporal integration of audio-visual speech perception: An EEG study

    OpenAIRE

    G. Vinodh Kumar; Tamesh Halder; Amit Kumar Jaiswal; Abhishek Mukherjee; Dipanjan Roy; Arpan Banerjee

    2016-01-01

    Observable lip movements of the speaker influence perception of auditory speech. A classical example of this influence is reported by listeners who perceive an illusory (cross-modal) speech sound (McGurk-effect) when presented with incongruent audio-visual (AV) speech stimuli. Recent neuroimaging studies of AV speech perception accentuate the role of frontal, parietal, and the integrative brain sites in the vicinity of the superior temporal sulcus (STS) for multisensory speech perception. How...

  5. fMRI brain response during sentence reading comprehension in children with benign epilepsy with centro-temporal spikes.

    Science.gov (United States)

    Malfait, D; Tucholka, A; Mendizabal, S; Tremblay, J; Poulin, C; Oskoui, M; Srour, M; Carmant, L; Major, P; Lippé, S

    2015-11-01

    Children with benign epilepsy with centro-temporal spikes (BECTS) often have language problems. Abnormal epileptic activity is found in central and temporal brain regions, which are involved in reading and semantic and syntactic comprehension. Using functional magnetic resonance imaging (fMRI), we examined reading networks in BECTS children with a new sentence reading comprehension task involving semantic and syntactic processing. Fifteen children with BECTS (age=11y 1m ± 16 m; 12 boys) and 18 healthy controls (age=11 y 8m ± 20 m; 11 boys) performed an fMRI reading comprehension task in which they read a pair of syntactically complex sentences and decided whether the target sentence (the second sentence in the pair) was true or false with respect to the first sentence. All children also underwent an exhaustive neuropsychological assessment. We demonstrated weaknesses in several cognitive domains in BECTS children. During the sentence reading fMRI task, left inferior frontal regions and bilateral temporal areas were activated in BECTS children and healthy controls. However, additional brain regions such as the left hippocampus and precuneus were activated in BECTS children. Moreover, specific activation was found in the left caudate and putamen in BECTS children but not in healthy controls. Cognitive results and accuracy during the fMRI task were associated with specific brain activation patterns. BECTS children recruited a wider network to perform the fMRI sentence reading comprehension task, with specific activation in the left dorsal striatum. BECTS cognitive performance differently predicted functional activation in frontal and temporal regions compared to controls, suggesting differences in brain network organisation that contribute to reading comprehension. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  6. Recovery of Content and Temporal Order Memory for Performed Activities following Moderate to Severe Traumatic Brain Injury

    OpenAIRE

    Schmitter-Edgecombe, Maureen; Seelye, Adriana M.

    2012-01-01

    Few studies have investigated the complex nature of everyday activity memory following traumatic brain injury (TBI). This study examined recovery of content and temporal order memory for performed activities during the first year in individuals who suffered moderate to severe TBI. TBI and control participants completed eight different cognitive activities at baseline (i.e., acutely following injury for TBI) and then again approximately one year later (follow-up). Participants’ free recall of ...

  7. Temporal and spatial transcriptional fingerprints by antipsychotic or propsychotic drugs in mouse brain.

    Directory of Open Access Journals (Sweden)

    Kensuke Sakuma

    Full Text Available Various types of antipsychotics have been developed for the treatment of schizophrenia since the accidental discovery of the antipsychotic activity of chlorpromazine. Although all clinically effective antipsychotic agents have common properties to interact with the dopamine D2 receptor (D2R activation, their precise mechanisms of action remain elusive. Antipsychotics are well known to induce transcriptional changes of immediate early genes (IEGs, raising the possibility that gene expressions play an essential role to improve psychiatric symptoms. Here, we report that while different classes of antipsychotics have complex pharmacological profiles against D2R, they share common transcriptome fingerprint (TFP profile of IEGs in the murine brain in vivo by quantitative real-time PCR (qPCR. Our data showed that various types of antipsychotics with a profound interaction of D2R including haloperidol (antagonist, olanzapine (antagonist, and aripiprazole (partial agonist all share common spatial TFPs closely homologous to those of D2R antagonist sulpiride, and elicited greater transcriptional responses in the striatum than in the nucleus accumbens. Meanwhile, D2R agonist quinpirole and propsychotic NMDA antagonists such as MK-801 and phencyclidine (PCP exhibited the contrasting TFP profiles. Clozapine and propsychotic drug methamphetamine (MAP displayed peculiar TFPs that reflect their unique pharmacological property. Our results suggest that transcriptional responses are conserved across various types of antipsychotics clinically effective in positive symptoms of schizophrenia and also show that temporal and spatial TFPs may reflect the pharmacological features of the drugs. Thus, we propose that a TFP approach is beneficial to evaluate novel drug candidates for antipsychotic development.

  8. Disentangling meaning in the brain: Left temporal involvement in agreement processing.

    Science.gov (United States)

    Mancini, Simona; Quiñones, Ileana; Molinaro, Nicola; Hernandez-Cabrera, Juan A; Carreiras, Manuel

    2017-01-01

    Sentence comprehension is successfully accomplished by means of a form-to-meaning mapping procedure that relies on the extraction of morphosyntactic information from the input and its mapping to higher-level semantic-discourse representations. In this study, we sought to determine whether neuroanatomically distinct brain regions are involved in the processing of different types of information contained in the propositional meaning of a sentence, namely person and number. While person information indexes the role that an individual has in discourse (i.e., the speaker, the addressee or the entity being talked about by speaker and addressee), number indicates its cardinality (i.e., a single entity vs a multitude of entities). An event-related functional magnetic resonance imaging (fMRI) experiment was run using agreement-Correct and Person- and Number-violated sentences in Spanish, to disentangle the processing mechanisms and neural substrates associated with the building of discourse and cardinality representations. The contrast between Person and Number Violations showed qualitative and quantitative differences. A greater response for person compared to number was found in the left middle temporal gyrus (LMTG). However, critically, a posterior-to-anterior functional gradient emerged within this region. While the posterior portion of the LMTG was sensitive to both Person and Number Violations, the anterior portion of this region showed selective response for Person Violations. These results confirm that the comprehension of the propositional meaning of a sentence results from a composite, feature-sensitive mechanism of form-to-meaning mapping in which the nodes of the language network are differentially involved. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. With or without you: predictive coding and Bayesian inference in the brain.

    Science.gov (United States)

    Aitchison, Laurence; Lengyel, Máté

    2017-10-01

    Two theoretical ideas have emerged recently with the ambition to provide a unifying functional explanation of neural population coding and dynamics: predictive coding and Bayesian inference. Here, we describe the two theories and their combination into a single framework: Bayesian predictive coding. We clarify how the two theories can be distinguished, despite sharing core computational concepts and addressing an overlapping set of empirical phenomena. We argue that predictive coding is an algorithmic/representational motif that can serve several different computational goals of which Bayesian inference is but one. Conversely, while Bayesian inference can utilize predictive coding, it can also be realized by a variety of other representations. We critically evaluate the experimental evidence supporting Bayesian predictive coding and discuss how to test it more directly. Copyright © 2017. Published by Elsevier Ltd.

  10. Recovery of content and temporal order memory for performed activities following moderate to severe traumatic brain injury.

    Science.gov (United States)

    Schmitter-Edgecombe, Maureen; Seelye, Adriana M

    2012-01-01

    Few studies have investigated the complex nature of everyday activity memory following traumatic brain injury (TBI). This study examined recovery of content and temporal order memory for performed activities during the first year in individuals who suffered moderate to severe TBI. TBI and control participants completed eight different cognitive activities at baseline (i.e., acutely following injury for TBI) and then again approximately one year later (follow-up). Participants' free recall of the activities provided a measure of content memory. Temporal order memory was assessed with a reconstruction task. Self-report and informant report of everyday memory problems at follow-up were used to examine the relationship between activity memory performances and everyday memory. TBI participants showed significant recovery in both content and temporal order memory for activities during the first year. Despite showing significant recovery, the TBI group's activity memory performances remained poorer than that of controls at follow-up. Greater self- and informant report of everyday memory difficulties was associated with poorer temporal order memory but not content memory for activities. These findings demonstrate recovery in multiple memory processes that support activity memory following moderate to severe TBI. The findings also suggest a stronger link between everyday memory abilities and temporal order memory for activities than activity memory content in a TBI population.

  11. Brain activity related to working memory for temporal order and object information.

    Science.gov (United States)

    Roberts, Brooke M; Libby, Laura A; Inhoff, Marika C; Ranganath, Charan

    2017-06-08

    Maintaining items in an appropriate sequence is important for many daily activities; however, remarkably little is known about the neural basis of human temporal working memory. Prior work suggests that the prefrontal cortex (PFC) and medial temporal lobe (MTL), including the hippocampus, play a role in representing information about temporal order. The involvement of these areas in successful temporal working memory, however, is less clear. Additionally, it is unknown whether regions in the PFC and MTL support temporal working memory across different timescales, or at coarse or fine levels of temporal detail. To address these questions, participants were scanned while completing 3 working memory task conditions (Group, Position and Item) that were matched in terms of difficulty and the number of items to be actively maintained. Group and Position trials probed temporal working memory processes, requiring the maintenance of hierarchically organized coarse and fine temporal information, respectively. To isolate activation related to temporal working memory, Group and Position trials were contrasted against Item trials, which required detailed working memory maintenance of visual objects. Results revealed that working memory encoding and maintenance of temporal information relative to visual information was associated with increased activation in dorsolateral PFC (DLPFC), and perirhinal cortex (PRC). In contrast, maintenance of visual details relative to temporal information was characterized by greater activation of parahippocampal cortex (PHC), medial and anterior PFC, and retrosplenial cortex. In the hippocampus, a dissociation along the longitudinal axis was observed such that the anterior hippocampus was more active for working memory encoding and maintenance of visual detail information relative to temporal information, whereas the posterior hippocampus displayed the opposite effect. Posterior parietal cortex was the only region to show sensitivity to temporal

  12. Probabilistic Algorithm for Electromagnetic Brain Imaging with Spatio-Temporal and Forward Model Priors

    DEFF Research Database (Denmark)

    Stahlhut, Carsten; Wipf, David; Attias, Hagai T.

    2010-01-01

    In this paper we present a novel spatio-temporal inverse method for solving the inverse M/EEG problem. The contribution is two-folded; firstly, the proposed model allows for a sparse spatial and temporal source representation of the M/EEG by applying an automatic relevance determination type prior...

  13. Spatial and Temporal Episodic Memory Retrieval Recruit Dissociable Functional Networks in the Human Brain

    Science.gov (United States)

    Ekstrom, Arne D.; Bookheimer, Susan Y.

    2007-01-01

    Imaging, electrophysiological studies, and lesion work have shown that the medial temporal lobe (MTL) is important for episodic memory; however, it is unclear whether different MTL regions support the spatial, temporal, and item elements of episodic memory. In this study we used fMRI to examine retrieval performance emphasizing different aspects…

  14. Detection of whole-brain abnormalities in temporal lobe epilepsy using tensor-based morphometry with DARTEL

    Science.gov (United States)

    Li, Wenjing; He, Huiguang; Lu, Jingjing; Lv, Bin; Li, Meng; Jin, Zhengyu

    2009-10-01

    Tensor-based morphometry (TBM) is an automated technique for detecting the anatomical differences between populations by examining the gradients of the deformation fields used to nonlinearly warp MR images. The purpose of this study was to investigate the whole-brain volume changes between the patients with unilateral temporal lobe epilepsy (TLE) and the controls using TBM with DARTEL, which could achieve more accurate inter-subject registration of brain images. T1-weighted images were acquired from 21 left-TLE patients, 21 right-TLE patients and 21 healthy controls, which were matched in age and gender. The determinants of the gradient of deformation fields at voxel level were obtained to quantify the expansion or contraction for individual images relative to the template, and then logarithmical transformation was applied on it. A whole brain analysis was performed using general lineal model (GLM), and the multiple comparison was corrected by false discovery rate (FDR) with p<0.05. For left-TLE patients, significant volume reductions were found in hippocampus, cingulate gyrus, precentral gyrus, right temporal lobe and cerebellum. These results potentially support the utility of TBM with DARTEL to study the structural changes between groups.

  15. Absence of Doppler signal in transcranial color-coded ultrasonography may be confirmatory for brain death: A case report

    Directory of Open Access Journals (Sweden)

    Mehmet Akif Topçuoğlu

    2015-08-01

    Full Text Available Transcranial Doppler ultrasonography (TCD is a valuable tool for demonstrating cerebral circulatory arrest (CCA in the setting of brain death. Complete reversal of diastolic flow (to-and-fro flow and systolic spikes in bilateral terminal internal carotid arteries and vertebrobasilar circulation are considered as specific sonogram configurations supporting the diagnosis of CCA. Because of the possibility of sonic bone window impermeability, absence of any waveform in TCD is not confirmatory for CCA unless there is documentation of disappearance of a previously well detected signal by the same recording settings. Transcranial color-coded sonography (TCCS with B-mode imaging can reliably detect adequacy of bone windows with clarity contralateral skull and ipsilateral planum temporale visualization. Therefore, absence of detectable intracranial Doppler signal along with available ultrasound window in TCCS can confirm clinical diagnosis of brain death. We herein discuss this entity from the frame of a representative case.

  16. On the Same Wavelength: Predictable Language Enhances Speaker–Listener Brain-to-Brain Synchrony in Posterior Superior Temporal Gyrus

    NARCIS (Netherlands)

    Dikker, Suzanne|info:eu-repo/dai/nl/374650403; Silbert, Lauren J; Hasson, Uri; Zevin, Jason D

    2014-01-01

    Recent research has shown that the degree to which speakers and listeners exhibit similar brain activity patterns during human linguistic interaction is correlated with communicative success. Here, we used an intersubject correlation approach in fMRI to test the hypothesis that a listener's ability

  17. A scalable multi-resolution spatio-temporal model for brain activation and connectivity in fMRI data

    KAUST Repository

    Castruccio, Stefano

    2018-01-23

    Functional Magnetic Resonance Imaging (fMRI) is a primary modality for studying brain activity. Modeling spatial dependence of imaging data at different spatial scales is one of the main challenges of contemporary neuroimaging, and it could allow for accurate testing for significance in neural activity. The high dimensionality of this type of data (on the order of hundreds of thousands of voxels) poses serious modeling challenges and considerable computational constraints. For the sake of feasibility, standard models typically reduce dimensionality by modeling covariance among regions of interest (ROIs)—coarser or larger spatial units—rather than among voxels. However, ignoring spatial dependence at different scales could drastically reduce our ability to detect activation patterns in the brain and hence produce misleading results. We introduce a multi-resolution spatio-temporal model and a computationally efficient methodology to estimate cognitive control related activation and whole-brain connectivity. The proposed model allows for testing voxel-specific activation while accounting for non-stationary local spatial dependence within anatomically defined ROIs, as well as regional dependence (between-ROIs). The model is used in a motor-task fMRI study to investigate brain activation and connectivity patterns aimed at identifying associations between these patterns and regaining motor functionality following a stroke.

  18. A scalable multi-resolution spatio-temporal model for brain activation and connectivity in fMRI data.

    Science.gov (United States)

    Castruccio, Stefano; Ombao, Hernando; Genton, Marc G

    2018-01-22

    Functional Magnetic Resonance Imaging (fMRI) is a primary modality for studying brain activity. Modeling spatial dependence of imaging data at different spatial scales is one of the main challenges of contemporary neuroimaging, and it could allow for accurate testing for significance in neural activity. The high dimensionality of this type of data (on the order of hundreds of thousands of voxels) poses serious modeling challenges and considerable computational constraints. For the sake of feasibility, standard models typically reduce dimensionality by modeling covariance among regions of interest (ROIs)-coarser or larger spatial units-rather than among voxels. However, ignoring spatial dependence at different scales could drastically reduce our ability to detect activation patterns in the brain and hence produce misleading results. We introduce a multi-resolution spatio-temporal model and a computationally efficient methodology to estimate cognitive control related activation and whole-brain connectivity. The proposed model allows for testing voxel-specific activation while accounting for non-stationary local spatial dependence within anatomically defined ROIs, as well as regional dependence (between-ROIs). The model is used in a motor-task fMRI study to investigate brain activation and connectivity patterns aimed at identifying associations between these patterns and regaining motor functionality following a stroke. © 2018, The International Biometric Society.

  19. Resenha/Book Review DEHAENE, Stanislav. Consciousness and the brain: Deciphering how the brain codes our thoughts. New York: Viking Penguin, 2014. 336p. ISBN 978-0-670-02543-5.

    Directory of Open Access Journals (Sweden)

    Rosângela Gabriel

    2016-01-01

    Full Text Available http://dx.doi.org/10.5007/2175-8026.2016v69n1p261 Trata-se de uma resenha do livro "Consciousness and the brain: deciphering how the brain codes our thought", da autoria de Stanislav Dehaene, publicado em 2014, pela Editora Vicking nos Estados Unidos.

  20. A novel Morse code-inspired method for multiclass motor imagery brain-computer interface (BCI) design.

    Science.gov (United States)

    Jiang, Jun; Zhou, Zongtan; Yin, Erwei; Yu, Yang; Liu, Yadong; Hu, Dewen

    2015-11-01

    Motor imagery (MI)-based brain-computer interfaces (BCIs) allow disabled individuals to control external devices voluntarily, helping us to restore lost motor functions. However, the number of control commands available in MI-based BCIs remains limited, limiting the usability of BCI systems in control applications involving multiple degrees of freedom (DOF), such as control of a robot arm. To address this problem, we developed a novel Morse code-inspired method for MI-based BCI design to increase the number of output commands. Using this method, brain activities are modulated by sequences of MI (sMI) tasks, which are constructed by alternately imagining movements of the left or right hand or no motion. The codes of the sMI task was detected from EEG signals and mapped to special commands. According to permutation theory, an sMI task with N-length allows 2 × (2(N)-1) possible commands with the left and right MI tasks under self-paced conditions. To verify its feasibility, the new method was used to construct a six-class BCI system to control the arm of a humanoid robot. Four subjects participated in our experiment and the averaged accuracy of the six-class sMI tasks was 89.4%. The Cohen's kappa coefficient and the throughput of our BCI paradigm are 0.88 ± 0.060 and 23.5bits per minute (bpm), respectively. Furthermore, all of the subjects could operate an actual three-joint robot arm to grasp an object in around 49.1s using our approach. These promising results suggest that the Morse code-inspired method could be used in the design of BCIs for multi-DOF control. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Beacon signal in transcranial color coded ultrasound: A sign for brain death

    Directory of Open Access Journals (Sweden)

    Mehmet Akif Topçuoğlu

    2014-04-01

    Full Text Available A widely under-recognized brain-death confirming transcranial ultrasonography pattern resembling the red-blue beacon signal was demonstrated. Familiarity to this distinct and characteristic ultrasonic pattern seems to be important in the perspective of point-of-care neurological ultrasound use and knobology.

  2. Temporal Loss of Tsc1: Neural Development and Brain Disease in Tuberous Sclerosis

    Science.gov (United States)

    2013-06-01

    brain development causes neurological disease in Tuberous Sclerosis". Honorary Lecturer at 8th Annual Pharmacology Graduate Students’ Symposium...Orthopedics and Surgery at Rhode Island Hospital and the Warren Alpert Medical School at Brown University, Providence, RI 02903, USA *Correspondence...analysis, five thalamic regions from five medial-to-lateral brain sections were assessed. The measure function (Voloc- ity) was used to calculate the

  3. Changes in brain entropy are related to abstract temporal topology. Comment on "Topodynamics of metastable brains" by Arturo Tozzi et al.

    Science.gov (United States)

    Çankaya, Mehmet Niyazi; Déli, Eva

    2017-07-01

    of the brain's electric activities that parallel changes in thoughts or evolution of concepts. Within the framework of operational architectonics, Tozzi et al. applied the methods of the Bursuk-Ulam theorem (BUT) to uncover the detailed dynamics of brain activities, such as dimensionality, entropy changes, and information accumulation. The authors find that ripples of rapid transitional periods, with sudden changes and reorganization of the information and entropy, parallels shifts both in dimensionality of temporal dynamics, as well as in cognitive processes. The method therefore can uncover how entropic and dimensionality changes are interconnected with emerging mental concepts. It also highlights the differences between lower conceptual processes, such as sensory processing, and higher cognitive synthesis, such as semantics, for example. In physical systems, information, dimensionality and entropy are related according to well-established formulas. In this direction, the entropy values of the volume and surface area are added into the evaluation of brain functionings [5-7]. If the same relationship is true in the wet and constantly changing biological complexity of the brain, then it would give us predictive capability toward the understanding of cognition, aid the treatment of mental problems and diseases in psychiatry and psychology, and facilitate the design of a new generation of artificial intelligent machines.

  4. It's a matter of time: Reframing the development of cognitive control as a modification of the brain's temporal dynamics.

    Science.gov (United States)

    Hutchison, R Matthew; Morton, J Bruce

    2016-04-01

    Cognitive control is a process that unfolds over time and regulates thought and action in the service of achieving goals and managing unanticipated challenges. Prevailing accounts attribute the protracted development of this mental process to incremental changes in the functional organization of a cognitive control network. Here, we challenge the notion that cognitive control is linked to a topologically static network, and argue that the capacity to manage unanticipated challenges and its development should instead be characterized in terms of inter-regional functional coupling dynamics. Ongoing changes in temporal coupling have long represented a fundamental pillar in both empirical and theoretical-based accounts of brain function, but have been largely ignored by traditional neuroimaging methods that assume a fixed functional architecture. There is, however, a growing recognition of the importance of temporal coupling dynamics for brain function, and this has led to rapid innovations in analytic methods. Results in this new frontier of neuroimaging suggest that time-varying changes in connectivity strength and direction exist at the large scale and further, that network patterns, like cognitive control process themselves, are transient and dynamic. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. EEG microstates as a tool for studying the temporal dynamics of whole-brain neuronal networks: A review.

    Science.gov (United States)

    Michel, Christoph M; Koenig, Thomas

    2017-11-28

    The present review discusses a well-established method for characterizing resting-state activity of the human brain using multichannel electroencephalography (EEG). This method involves the examination of electrical microstates in the brain, which are defined as successive short time periods during which the configuration of the scalp potential field remains semi-stable, suggesting quasi-simultaneity of activity among the nodes of large-scale networks. A few prototypic microstates, which occur in a repetitive sequence across time, can be reliably identified across participants. Researchers have proposed that these microstates represent the basic building blocks of the chain of spontaneous conscious mental processes, and that their occurrence and temporal dynamics determine the quality of mentation. Several studies have further demonstrated that disturbances of mental processes associated with neurological and psychiatric conditions manifest as changes in the temporal dynamics of specific microstates. Combined EEG-fMRI studies and EEG source imaging studies have indicated that EEG microstates are closely associated with resting-state networks as identified using fMRI. The scale-free properties of the time series of EEG microstates explain why similar networks can be observed at such different time scales. The present review will provide an overview of these EEG microstates, available methods for analysis, the functional interpretations of findings regarding these microstates, and their behavioral and clinical correlates. Copyright © 2017. Published by Elsevier Inc.

  6. Large Scale Functional Brain Networks Underlying Temporal Integration of Audio-Visual Speech Perception: An EEG Study.

    Science.gov (United States)

    Kumar, G Vinodh; Halder, Tamesh; Jaiswal, Amit K; Mukherjee, Abhishek; Roy, Dipanjan; Banerjee, Arpan

    2016-01-01

    Observable lip movements of the speaker influence perception of auditory speech. A classical example of this influence is reported by listeners who perceive an illusory (cross-modal) speech sound (McGurk-effect) when presented with incongruent audio-visual (AV) speech stimuli. Recent neuroimaging studies of AV speech perception accentuate the role of frontal, parietal, and the integrative brain sites in the vicinity of the superior temporal sulcus (STS) for multisensory speech perception. However, if and how does the network across the whole brain participates during multisensory perception processing remains an open question. We posit that a large-scale functional connectivity among the neural population situated in distributed brain sites may provide valuable insights involved in processing and fusing of AV speech. Varying the psychophysical parameters in tandem with electroencephalogram (EEG) recordings, we exploited the trial-by-trial perceptual variability of incongruent audio-visual (AV) speech stimuli to identify the characteristics of the large-scale cortical network that facilitates multisensory perception during synchronous and asynchronous AV speech. We evaluated the spectral landscape of EEG signals during multisensory speech perception at varying AV lags. Functional connectivity dynamics for all sensor pairs was computed using the time-frequency global coherence, the vector sum of pairwise coherence changes over time. During synchronous AV speech, we observed enhanced global gamma-band coherence and decreased alpha and beta-band coherence underlying cross-modal (illusory) perception compared to unisensory perception around a temporal window of 300-600 ms following onset of stimuli. During asynchronous speech stimuli, a global broadband coherence was observed during cross-modal perception at earlier times along with pre-stimulus decreases of lower frequency power, e.g., alpha rhythms for positive AV lags and theta rhythms for negative AV lags. Thus, our

  7. Large scale functional brain networks underlying temporal integration of audio-visual speech perception: An EEG study

    Directory of Open Access Journals (Sweden)

    G. Vinodh Kumar

    2016-10-01

    Full Text Available Observable lip movements of the speaker influence perception of auditory speech. A classical example of this influence is reported by listeners who perceive an illusory (cross-modal speech sound (McGurk-effect when presented with incongruent audio-visual (AV speech stimuli. Recent neuroimaging studies of AV speech perception accentuate the role of frontal, parietal and the integrative brain sites in the vicinity of the superior temporal sulcus (STS for multisensory speech perception. However, if and how does the network across the whole brain participates during multisensory perception processing remains an open question. We posit that a large-scale functional connectivity among the neural population situated in distributed brain sites may provide valuable insights involved in processing and fusing of AV speech. Varying the psychophysical parameters in tandem with electroencephalogram (EEG recordings, we exploited the trial-by-trial perceptual variability of incongruent audio-visual (AV speech stimuli to identify the characteristics of the large-scale cortical network that facilitates multisensory perception during synchronous and asynchronous AV speech. We evaluated the spectral landscape of EEG signals during multisensory speech perception at varying AV lags. Functional connectivity dynamics for all sensor pairs was computed using the time-frequency global coherence, the vector sum of pairwise coherence changes over time. During synchronous AV speech, we observed enhanced global gamma-band coherence and decreased alpha and beta-band coherence underlying cross-modal (illusory perception compared to unisensory perception around a temporal window of 300-600 ms following onset of stimuli. During asynchronous speech stimuli, a global broadband coherence was observed during cross-modal perception at earlier times along with pre-stimulus decreases of lower frequency power, e.g., alpha rhythms for positive AV lags and theta rhythms for negative AV

  8. A cross-sectional MRI study of brain regional atrophy and clinical characteristics of temporal lobe epilepsy with hippocampal sclerosis.

    LENUS (Irish Health Repository)

    2012-02-01

    PURPOSE: Applying a cross-sectional design, we set out to further characterize the significance of extrahippocampal brain atrophy in a large sample of \\'sporadic\\' mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE+HS). By evaluating the influence of epilepsy chronicity on structural atrophy, this work represents an important step towards the characterization of MRI-based volumetric measurements as genetic endophenotypes for this condition. METHODS: Using an automated brain segmentation technique, MRI-based volume measurements of several brain regions were compared between 75 patients with \\'sporadic\\' MTLE+HS and 50 healthy controls. Applying linear regression models, we examined the relationship between structural atrophy and important clinical features of MTLE+HS, including disease duration, lifetime number of partial and generalized seizures, and history of initial precipitating insults (IPIs). RESULTS: Significant volume loss was detected in ipsilateral hippocampus, amygdala, thalamus, and cerebral white matter (WM). In addition, contralateral hippocampal and bilateral cerebellar grey matter (GM) volume loss was observed in left MTLE+HS patients. Hippocampal, amygdalar, and cerebral WM volume loss correlated with duration of epilepsy. This correlation was stronger in patients with prior IPIs history. Further, cerebral WM, cerebellar GM, and contralateral hippocampal volume loss correlated with lifetime number of generalized seizures. CONCLUSION: Our findings confirm that multiple brain regions beyond the hippocampus are involved in the pathogenesis of MTLE+HS. IPIs are an important factor influencing the rate of regional atrophy but our results also support a role for processes related to epilepsy chronicity. The consequence of epilepsy chronicity on candidate brain regions has important implications on their application as genetic endophenotypes.

  9. Analysis of Parkinson's disease brain-derived DNA for alpha-synuclein coding somatic mutations.

    Science.gov (United States)

    Proukakis, Christos; Shoaee, Maryiam; Morris, James; Brier, Timothy; Kara, Eleanna; Sheerin, Una-Marie; Charlesworth, Gavin; Tolosa, Eduardo; Houlden, Henry; Wood, Nicholas W; Schapira, Anthony H

    2014-07-01

    Although alpha-synuclein (SNCA) is crucial to the pathogenesis of Parkinson's disease (PD) and dementia with Lewy bodies (DLB), mutations in the gene appear to be rare. We have recently hypothesized that somatic mutations in early development could contribute to PD. Expanding on our recent negative small study, we used high-resolution melting (HRM) analysis to screen SNCA coding exons for somatic point mutations in DNA from 539 PD and DLB cerebellar samples, with two additional regions (frontal cortex, substantia nigra) for 20 PD cases. We used artificial mosaics to determine sensitivity where possible. We did not detect any evidence of somatic coding mutations. Three cases were heterozygous for known silent polymorphisms. The protocol we used was sensitive enough to detect 5% to 10% mutant DNA. Using DNA predominantly from cerebellum, but also from frontal cortex and substantia nigra (n = 20 each), we have not detected any somatic coding SNCA point mutations. © 2014 The Authors. International Parkinson and Movement Disorder Society published by Wiley Periodicals, Inc.

  10. Characterizing functional integrity: intraindividual brain signal variability predicts memory performance in patients with medial temporal lobe epilepsy.

    Science.gov (United States)

    Protzner, Andrea B; Kovacevic, Natasa; Cohn, Melanie; McAndrews, Mary Pat

    2013-06-05

    Computational modeling suggests that variability in brain signals provides important information regarding the system's capacity to adopt different network configurations that may promote optimal responding to stimuli. Although there is limited empirical work on this construct, a recent study indicates that age-related decreases in variability across the adult lifespan correlate with less efficient and less accurate performance. Here, we extend this construct to the assessment of cerebral integrity by comparing fMRI BOLD variability and fMRI BOLD amplitude in their ability to account for differences in functional capacity in patients with focal unilateral medial temporal dysfunction. We were specifically interested in whether either of these BOLD measures could identify a link between the affected medial temporal region and memory performance (as measured by a clinical test of verbal memory retention). Using partial least-squares analyses, we found that variability in a set of regions including the left hippocampus predicted verbal retention and, furthermore, this relationship was similar across a range of cognitive tasks measured during scanning (i.e., the same pattern was seen in fixation, autobiographical recall, and word generation). In contrast, signal amplitude in the hippocampus did not predict memory performance, even for a task that reliably activates the medial temporal lobes (i.e., autobiographical recall). These findings provide a powerful validation of the concept that variability in brain signals reflects functional integrity. Furthermore, this measure can be characterized as a robust biomarker in this clinical setting because it reveals the same pattern regardless of cognitive challenge or task engagement during scanning.

  11. Automating cell detection and classification in human brain fluorescent microscopy images using dictionary learning and sparse coding.

    Science.gov (United States)

    Alegro, Maryana; Theofilas, Panagiotis; Nguy, Austin; Castruita, Patricia A; Seeley, William; Heinsen, Helmut; Ushizima, Daniela M; Grinberg, Lea T

    2017-04-15

    Immunofluorescence (IF) plays a major role in quantifying protein expression in situ and understanding cell function. It is widely applied in assessing disease mechanisms and in drug discovery research. Automation of IF analysis can transform studies using experimental cell models. However, IF analysis of postmortem human tissue relies mostly on manual interaction, often subjected to low-throughput and prone to error, leading to low inter and intra-observer reproducibility. Human postmortem brain samples challenges neuroscientists because of the high level of autofluorescence caused by accumulation of lipofuscin pigment during aging, hindering systematic analyses. We propose a method for automating cell counting and classification in IF microscopy of human postmortem brains. Our algorithm speeds up the quantification task while improving reproducibility. Dictionary learning and sparse coding allow for constructing improved cell representations using IF images. These models are input for detection and segmentation methods. Classification occurs by means of color distances between cells and a learned set. Our method successfully detected and classified cells in 49 human brain images. We evaluated our results regarding true positive, false positive, false negative, precision, recall, false positive rate and F1 score metrics. We also measured user-experience and time saved compared to manual countings. We compared our results to four open-access IF-based cell-counting tools available in the literature. Our method showed improved accuracy for all data samples. The proposed method satisfactorily detects and classifies cells from human postmortem brain IF images, with potential to be generalized for applications in other counting tasks. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Noise activated bistable sensor based on chaotic system with output defined by temporal coding and firing rate

    Science.gov (United States)

    Korneta, Wojciech; Gomes, Iacyel

    2017-11-01

    Traditional bistable sensors use external bias signal to drive its response between states and their detection strategy is based on the output power spectral density or the residence time difference (RTD) in two sensor states. Recently, the noise activated nonlinear dynamic sensors driven only by noise based on RTD technique have been proposed. Here, we present experimental results of dc voltage measurements by noise-driven bistable sensor based on electronic Chua's circuit operating in a chaotic regime where two single scroll attractors coexist. The output of the sensor is quantified by the proportion of the time the sensor stays in one state to the total observation time and by the spike-count rate with spikes defined by crossings between attractors. The relationship between the stimuli and particular observable for different noise intensities is obtained, the usefulness of each coding scheme is discussed, and the optimal noise intensity for detection is indicated. It is shown that the obtained relationship is the same for any observation time when population coding is used. The optimal time window for both detection and the number of units in population coding is found. Our results may be useful for analyses and understanding of the neural activity and in designing bistable storage elements at length scales where thermal fluctuations drastically increase and the effect of noise must be taken into consideration.

  13. Temporal changes of diffusion patterns in mild traumatic brain injury via group-based semi-blind source separation.

    Science.gov (United States)

    Jing, Min; McGinnity, T Martin; Coleman, Sonya; Fuchs, Armin; Kelso, J A Scott

    2015-07-01

    Despite the emerging applications of diffusion tensor imaging (DTI) to mild traumatic brain injury (mTBI), very few investigations have been reported related to temporal changes in quantitative diffusion patterns, which may help to assess recovery from head injury and the long term impact associated with cognitive and behavioral impairments caused by mTBI. Most existing methods are focused on detection of mTBI affected regions rather than quantification of temporal changes following head injury. Furthermore, most methods rely on large data samples as required for statistical analysis and, thus, are less suitable for individual case studies. In this paper, we introduce an approach based on spatial group independent component analysis (GICA), in which the diffusion scalar maps from an individual mTBI subject and the average of a group of controls are arranged according to their data collection time points. In addition, we propose a constrained GICA (CGICA) model by introducing the prior information into the GICA decomposition process, thus taking available knowledge of mTBI into account. The proposed method is evaluated based on DTI data collected from American football players including eight controls and three mTBI subjects (at three time points post injury). The results show that common spatial patterns within the diffusion maps were extracted as spatially independent components (ICs) by GICA. The temporal change of diffusion patterns during recovery is revealed by the time course of the selected IC. The results also demonstrate that the temporal change can be further influenced by incorporating the prior knowledge of mTBI (if available) based on the proposed CGICA model. Although a small sample of mTBI subjects is studied, as a proof of concept, the preliminary results provide promising insight for applications of DTI to study recovery from mTBI and may have potential for individual case studies in practice.

  14. Temporal Hierarchical Adaptive Texture CRF for Automatic Detection of Gadolinium-Enhancing Multiple Sclerosis Lesions in Brain MRI.

    Science.gov (United States)

    Karimaghaloo, Zahra; Rivaz, Hassan; Arnold, Douglas L; Collins, D Louis; Arbel, Tal

    2015-06-01

    We propose a conditional random field (CRF) based classifier for segmentation of small enhanced pathologies. Specifically, we develop a temporal hierarchical adaptive texture CRF (THAT-CRF) and apply it to the challenging problem of gad enhancing lesion segmentation in brain MRI of patients with multiple sclerosis. In this context, the presence of many nonlesion enhancements (such as blood vessels) renders the problem more difficult. In addition to voxel-wise features, the framework exploits multiple higher order textures to discriminate the true lesional enhancements from the pool of other enhancements. Since lesional enhancements show more variation over time as compared to the nonlesional ones, we incorporate temporal texture analysis in order to study the textures of enhanced candidates over time. The parameters of the THAT-CRF model are learned based on 2380 scans from a multi-center clinical trial. The effect of different components of the model is extensively evaluated on 120 scans from a separate multi-center clinical trial. The incorporation of the temporal textures results in a general decrease of the false discovery rate. Specifically, THAT-CRF achieves overall sensitivity of 95% along with false discovery rate of 20% and average false positive count of 0.5 lesions per scan. The sensitivity of the temporal method to the trained time interval is further investigated on five different intervals of 69 patients. Moreover, superior performance is achieved by the reviewed labelings of our model compared to the fully manual labeling when applied to the context of separating different treatment arms in a real clinical trial.

  15. Pathological and Pathophysiological Alterations in Temporal Lobe Structures After Mild Traumatic Brain Injury

    Science.gov (United States)

    2014-01-31

    levels in the cerebral cortex following experimental brain trauma in rats. Journal of neurotrauma 16:501-10 129. Hicks RR, Martin VB, Zhang L...state following experimental head injury. Neurosurg Rev 12 Suppl 1:400-11 288. Swanson LW, Simmons DM, Whiting PJ, Lindstrom J. 1987

  16. Spatio-temporal regulation of circular RNA expression during porcine embryonic brain development

    DEFF Research Database (Denmark)

    Venø, Morten T; Hansen, Thomas B; Venø, Susanne T

    2015-01-01

    BACKGROUND: Recently, thousands of circular RNAs (circRNAs) have been discovered in various tissues and cell types from human, mouse, fruit fly and nematodes. However, expression of circRNAs across mammalian brain development has never been examined. RESULTS: Here we profile the expression of circ...

  17. Temporal Dynamics of Late Second Language Acquisition: Evidence from Event-Related Brain Potentials

    Science.gov (United States)

    Steinhauer, Karsten; White, Erin J.; Drury, John E.

    2009-01-01

    The ways in which age of acquisition (AoA) may affect (morpho)syntax in second language acquisition (SLA) are discussed. We suggest that event-related brain potentials (ERPs) provide an appropriate online measure to test some such effects. ERP findings of the past decade are reviewed with a focus on recent and ongoing research. It is concluded…

  18. Da Vinci Coding? Using Renaissance Artists’ Depictions of the Brain to Engage Student Interest in Neuroanatomy

    Science.gov (United States)

    Watson, Todd D.

    2013-01-01

    This report describes a pair of brief, interactive classroom exercises utilizing Renaissance artists’ depictions of the brain to help increase student interest in learning basic neuroanatomy. Undergraduate students provided anonymous quantitative evaluations of both exercises. The feedback data suggest that students found both exercises engaging. The data also suggest that the first exercise increased student interest in learning more about neuroanatomy in general, while the second provided useful practice in identifying major neuroanatomical structures. Overall, the data suggest that these exercises may be a useful addition to courses that introduce or review neuroanatomical concepts. PMID:23805058

  19. Da vinci coding? Using renaissance artists' depictions of the brain to engage student interest in neuroanatomy.

    Science.gov (United States)

    Watson, Todd D

    2013-01-01

    This report describes a pair of brief, interactive classroom exercises utilizing Renaissance artists' depictions of the brain to help increase student interest in learning basic neuroanatomy. Undergraduate students provided anonymous quantitative evaluations of both exercises. The feedback data suggest that students found both exercises engaging. The data also suggest that the first exercise increased student interest in learning more about neuroanatomy in general, while the second provided useful practice in identifying major neuroanatomical structures. Overall, the data suggest that these exercises may be a useful addition to courses that introduce or review neuroanatomical concepts.

  20. fMRI single trial discovery of spatio-temporal brain activity patterns.

    Science.gov (United States)

    Allegra, Michele; Seyed-Allaei, Shima; Pizzagalli, Fabrizio; Baftizadeh, Fahimeh; Maieron, Marta; Reverberi, Carlo; Laio, Alessandro; Amati, Daniele

    2017-03-01

    There is growing interest in the description of short-lived patterns in the spatiotemporal cortical activity monitored via neuroimaging. Most traditional analysis methods, designed to estimate relatively long-term brain dynamics, are not always appropriate to capture these patterns. Here we introduce a novel data-driven approach for detecting short-lived fMRI brain activity patterns. Exploiting Density Peak Clustering (Rodriguez and Laio [2014]), our approach reveals well localized clusters by identifying and grouping together voxels whose time-series are similar, irrespective of their brain location, even when very short time windows (∼10 volumes) are used. The method, which we call Coherence Density Peak Clustering (CDPC), is first tested on simulated data and compared with a standard unsupervised approach for fMRI analysis, independent component analysis (ICA). CDPC identifies activated voxels with essentially no false-positives and proves more reliable than ICA, which is troubled by a number of false positives comparable to that of true positives. The reliability of the method is demonstrated on real fMRI data from a simple motor task, containing brief iterations of the same movement. The clusters identified are found in regions expected to be involved in the task, and repeat synchronously with the paradigm. The methodology proposed is especially suitable for the study of short-time brain dynamics and single trial experiments, where the event or task of interest cannot be repeated for the same subject, as happens, for instance, in problem-solving, learning and decision-making. A GUI implementation of our method is available for download at https://github.com/micheleallegra/CDPC. Hum Brain Mapp 38:1421-1437, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Neuroproteomics and Systems Biology Approach to Identify Temporal Biomarker Changes Post Experimental Traumatic Brain Injury in Rats

    Directory of Open Access Journals (Sweden)

    Firas H Kobeissy

    2016-11-01

    Full Text Available Traumatic brain injury (TBI represents a critical health problem of which diagnosis, management and treatment remain challenging. TBI is a contributing factor in approximately 1/3 of all injury-related deaths in the United States. The Centers for Disease Control and Prevention (CDC estimate that 1.7 million TBI people suffer a TBI in the United States annually. Efforts continue to focus on elucidating the complex molecular mechanisms underlying TBI pathophysiology and defining sensitive and specific biomarkers that can aid in improving patient management and care. Recently, the area of neuroproteomics-systems biology is proving to be a prominent tool in biomarker discovery for central nervous system (CNS injury and other neurological diseases. In this work, we employed the controlled cortical impact (CCI model of experimental TBI in rat model to assess the temporal-global proteome changes after acute (1 day and for the first time, subacute (7 days, post-injury time frame using the established CAX-PAGE LC-MS/MS platform for protein separation combined with discrete systems biology analyses to identify temporal biomarker changes related to this rat TBI model. Rather than focusing on any one individual molecular entities, we used in silico systems biology approach to understand the global dynamics that govern proteins that are differentially altered post-injury. In addition, gene ontology analysis of the proteomic data was conducted in order to categorize the proteins by molecular function, biological process, and cellular localization. Results show alterations in several proteins related to inflammatory responses and oxidative stress in both acute (1 day and subacute (7 days periods post TBI. Moreover, results suggest a differential upregulation of neuroprotective proteins at 7-days post-CCI involved in cellular functions such as neurite growth, regeneration, and axonal guidance. Our study is amongst the first to assess temporal neuroproteome

  2. Brain magnetic resonance imaging findings in adult patients with congenital adrenal hyperplasia: Increased frequency of white matter impairment and temporal lobe structures dysgenesis

    Directory of Open Access Journals (Sweden)

    Mouna Feki Mnif

    2013-01-01

    Full Text Available Background: Congenital adrenal hyperplasia (CAH is an inherited recessive disorder of adrenal steroidogenesis. The enzymes most commonly affected are 21-hydroxylase. Past reports suggested brain magnetic resonance imaging (MRI abnormalities in CAH patients, affecting white matter signal, temporal lobe and amygdala structure and function. Aims: In the present study, we aimed to investigate the frequency of white matter changes and temporal lobes structures dysgenesis in a population of patients having CAH due to 21-hydroxylase deficiency. Materials and Methods: Neurological examination and brain MRI were performed in 26 patients. Results: Neurological examination revealed mental retardation in three patients, tremor in two patients, tendon reflexes asymmetry in one patient, and cerebellar syndrome in one patient. Eleven patients (42.3% showed MRI abnormalities: Eight of them had white matter hyperintensities, one patient had moderate atrophy in the right temporal, and hippocampal dysgenesis was found in the remaining two patients. Conclusions: Brain MRI abnormalities in CAH patients include white matter hyperintensities and temporal lobe structures dysgenesis. The mechanisms involved seem related to hormonal imbalances during brain development and exposure to excess exogenous glucocorticoids. Clinical implications of such lesions remain unclear. More extensive studies are required to define better the relationships between brain involvement and different CAH phenotypes and treatment regimens.

  3. High temporal discounters overvalue immediate rewards rather than undervalue future rewards: an event-related brain potential study.

    Science.gov (United States)

    Cherniawsky, Avital S; Holroyd, Clay B

    2013-03-01

    Impulsivity is characterized in part by heightened sensitivity to immediate relative to future rewards. Although previous research has suggested that "high discounters" in intertemporal choice tasks tend to prefer immediate over future rewards because they devalue the latter, it remains possible that they instead overvalue immediate rewards. To investigate this question, we recorded the reward positivity, a component of the event-related brain potential (ERP) associated with reward processing, with participants engaged in a task in which they received both immediate and future rewards and nonrewards. The participants also completed a temporal discounting task without ERP recording. We found that immediate but not future rewards elicited the reward positivity. High discounters also produced larger reward positivities to immediate rewards than did low discounters, indicating that high discounters relatively overvalued immediate rewards. These findings suggest that high discounters may be more motivated than low discounters to work for monetary rewards, irrespective of the time of arrival of the incentives.

  4. Naturalistic fMRI Mapping Reveals Superior Temporal Sulcus as the Hub for the Distributed Brain Network for Social Perception

    Science.gov (United States)

    Lahnakoski, Juha M.; Glerean, Enrico; Salmi, Juha; Jääskeläinen, Iiro P.; Sams, Mikko; Hari, Riitta; Nummenmaa, Lauri

    2012-01-01

    Despite the abundant data on brain networks processing static social signals, such as pictures of faces, the neural systems supporting social perception in naturalistic conditions are still poorly understood. Here we delineated brain networks subserving social perception under naturalistic conditions in 19 healthy humans who watched, during 3-T functional magnetic resonance imaging (fMRI), a set of 137 short (approximately 16 s each, total 27 min) audiovisual movie clips depicting pre-selected social signals. Two independent raters estimated how well each clip represented eight social features (faces, human bodies, biological motion, goal-oriented actions, emotion, social interaction, pain, and speech) and six filler features (places, objects, rigid motion, people not in social interaction, non-goal-oriented action, and non-human sounds) lacking social content. These ratings were used as predictors in the fMRI analysis. The posterior superior temporal sulcus (STS) responded to all social features but not to any non-social features, and the anterior STS responded to all social features except bodies and biological motion. We also found four partially segregated, extended networks for processing of specific social signals: (1) a fronto-temporal network responding to multiple social categories, (2) a fronto-parietal network preferentially activated to bodies, motion, and pain, (3) a temporo-amygdalar network responding to faces, social interaction, and speech, and (4) a fronto-insular network responding to pain, emotions, social interactions, and speech. Our results highlight the role of the pSTS in processing multiple aspects of social information, as well as the feasibility and efficiency of fMRI mapping under conditions that resemble the complexity of real life. PMID:22905026

  5. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex.

    Science.gov (United States)

    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S; Smolka, Michael N

    2014-11-01

    A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. We measured inhibitory control in 50 young adults with a stop-signal task during functional magnetic resonance imaging. In a single-blind placebo-controlled cross-over design, all participants performed the stop-signal task once under alcohol with a breath alcohol concentration of .6 g/kg and once under placebo. In addition, alcohol consumption was assessed with a free-access alcohol self-administration paradigm in the same participants. Inhibitory control was robustly decreased under alcohol compared with placebo, indicated by longer stop-signal reaction times. On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans, which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control might enhance alcohol consumption in young adults, which might promote future alcohol problems. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  6. Naturalistic fMRI mapping reveals superior temporal sulcus as the hub for the distributed brain network for social perception

    Directory of Open Access Journals (Sweden)

    Juha Marko Lahnakoski

    2012-08-01

    Full Text Available Despite the abundant data on brain networks processing static social signals, such as pictures of faces, the neural systems supporting social perception in naturalistic conditions are still poorly understood. Here we delineated brain networks subserving social perception under naturalistic conditions in 19 healthy humans who watched, during 3-tesla functional magnetic imaging (fMRI, a set of 137 short (~16 s each, total 27 min audiovisual movie clips depicting pre-selected social signals. Two independent raters estimated how well each clip represented eight social features (faces, human bodies, biological motion, goal-oriented actions, emotion, social interaction, pain, and speech and six filler features (places, objects, rigid motion, people not in social interaction, non-goal-oriented action and non-human sounds lacking social content. These ratings were used as predictors in the fMRI analysis. The posterior superior temporal sulcus (STS responded to all social features but not to any non-social features, and the anterior STS responded to all social features except bodies and biological motion. We also found four partially segregated, extended networks for processing of specific social signals: 1 a fronto-temporal network responding to multiple social categories, 2 a fronto-parietal network preferentially activated to bodies, motion and pain, 3 a temporo-amygdalar network responding to faces, social interaction and speech, and 4 a fronto-insular network responding to pain, emotions, social interactions, and speech. Our results highlight the role of the posterior STS in processing multiple aspects of social information, as well as the feasibility and efficiency of fMRI mapping under conditions that resemble the complexity of real life.

  7. Alcohol-induced impairment of inhibitory control is linked to attenuated brain responses in right fronto-temporal cortex

    Science.gov (United States)

    Gan, Gabriela; Guevara, Alvaro; Marxen, Michael; Neumann, Maike; Jünger, Elisabeth; Kobiella, Andrea; Mennigen, Eva; Pilhatsch, Maximilian; Schwarz, Daniel; Zimmermann, Ulrich S.; Smolka, Michael N.

    2014-01-01

    Background A self-enhancing loop between impaired inhibitory control under alcohol and alcohol consumption has been proposed as a possible mechanism underlying dysfunctional drinking in susceptible people. However, the neural underpinnings of alcohol-induced impairment of inhibitory control are widely unknown. Methods We measured inhibitory control in fifty young adults with a stop-signal task (SST) during functional magnetic resonance imaging (fMRI). In a single-blind placebo-controlled cross-over design, all participants performed the SST once under alcohol with a breath alcohol concentration (BrAC) of 0.6 g/kg, and once under placebo. In addition, alcohol consumption was assessed using a free-access alcohol self-administration (ASA) paradigm in the same participants. Results Inhibitory control was robustly decreased under alcohol compared to placebo indicated by longer stop-signal reaction times (SSRTs). On the neural level, impaired inhibitory control under alcohol was associated with attenuated brain responses in the right fronto-temporal portion of the inhibition network that supports the attentional capture of infrequent stop-signals, and subsequent updating of action plans from response execution to inhibition. Furthermore, the extent of alcohol-induced impairment of inhibitory control predicted free-access alcohol consumption. Conclusion We suggest that during inhibitory control alcohol affects cognitive processes preceding actual motor inhibition. Under alcohol, decreased brain responses in right fronto-temporal areas might slow down the attentional capture of infrequent stop-signals and subsequent updating of action plans which leads to impaired inhibitory control. In turn, pronounced alcohol-induced impairment of inhibitory control may enhance alcohol consumption in young adults which might promote future alcohol problems. PMID:24560581

  8. Multimedia human brain database system for surgical candidacy determination in temporal lobe epilepsy with content-based image retrieval

    Science.gov (United States)

    Siadat, Mohammad-Reza; Soltanian-Zadeh, Hamid; Fotouhi, Farshad A.; Elisevich, Kost

    2003-01-01

    This paper presents the development of a human brain multimedia database for surgical candidacy determination in temporal lobe epilepsy. The focus of the paper is on content-based image management, navigation and retrieval. Several medical image-processing methods including our newly developed segmentation method are utilized for information extraction/correlation and indexing. The input data includes T1-, T2-Weighted MRI and FLAIR MRI and ictal and interictal SPECT modalities with associated clinical data and EEG data analysis. The database can answer queries regarding issues such as the correlation between the attribute X of the entity Y and the outcome of a temporal lobe epilepsy surgery. The entity Y can be a brain anatomical structure such as the hippocampus. The attribute X can be either a functionality feature of the anatomical structure Y, calculated with SPECT modalities, such as signal average, or a volumetric/morphological feature of the entity Y such as volume or average curvature. The outcome of the surgery can be any surgery assessment such as memory quotient. A determination is made regarding surgical candidacy by analysis of both textual and image data. The current database system suggests a surgical determination for the cases with relatively small hippocampus and high signal intensity average on FLAIR images within the hippocampus. This indication pretty much fits with the surgeons" expectations/observations. Moreover, as the database gets more populated with patient profiles and individual surgical outcomes, using data mining methods one may discover partially invisible correlations between the contents of different modalities of data and the outcome of the surgery.

  9. Temporal- and Location-Specific Alterations of the GABA Recycling System in Mecp2 KO Mouse Brains

    Directory of Open Access Journals (Sweden)

    Seok K. Kang

    2014-01-01

    Full Text Available Rett syndrome (RTT, associated with mutations in methyl-CpG-binding protein 2 (Mecp2, is linked to diverse neurological symptoms such as seizures, motor disabilities, and cognitive impairments. An altered GABAergic system has been proposed as one of many underlying pathologies of progressive neurodegeneration in several RTT studies. This study for the first time investigated the temporal- and location-specific alterations in the expression of γ-amino butyric acid (GABA transporter 1 (GAT-1, vesicular GABA transporter (vGAT, and glutamic acid decarboxylase 67kD (GAD67 in wild type (WT and knockout (KO mice in the Mecp2 m1.1Bird/y mouse model of RTT. Immunohistochemistry (IHC co-labeling of GAT-1 with vGAT identified GABAergic synapses that were quantitated for mid-sagittal sections in the frontal cortex (FC, hippocampal dentate gyrus (DG, and striatum (Str. An age-dependent increase in the expression of synaptic GABA transporters, GAT-1, and vGAT, was observed in the FC and DG in WT brains. Mecp2 KO mice showed a significant alteration in this temporal profile that was location-specific, only in the FC. GAD67-positive cell densities also showed an age-dependent increase in the FC, but a decrease in the DG in WT mice. However, these densities were not significantly altered in the KO mice in the regions examined in this study. Therefore, the significant location-specific downregulation of synaptic GABA transporters in Mecp2 KO brains with unaltered densities of GAD67-positive interneurons may highlight the location-specific synaptic pathophysiology in this model of RTT.

  10. Naturalistic FMRI mapping reveals superior temporal sulcus as the hub for the distributed brain network for social perception.

    Science.gov (United States)

    Lahnakoski, Juha M; Glerean, Enrico; Salmi, Juha; Jääskeläinen, Iiro P; Sams, Mikko; Hari, Riitta; Nummenmaa, Lauri

    2012-01-01

    Despite the abundant data on brain networks processing static social signals, such as pictures of faces, the neural systems supporting social perception in naturalistic conditions are still poorly understood. Here we delineated brain networks subserving social perception under naturalistic conditions in 19 healthy humans who watched, during 3-T functional magnetic resonance imaging (fMRI), a set of 137 short (approximately 16 s each, total 27 min) audiovisual movie clips depicting pre-selected social signals. Two independent raters estimated how well each clip represented eight social features (faces, human bodies, biological motion, goal-oriented actions, emotion, social interaction, pain, and speech) and six filler features (places, objects, rigid motion, people not in social interaction, non-goal-oriented action, and non-human sounds) lacking social content. These ratings were used as predictors in the fMRI analysis. The posterior superior temporal sulcus (STS) responded to all social features but not to any non-social features, and the anterior STS responded to all social features except bodies and biological motion. We also found four partially segregated, extended networks for processing of specific social signals: (1) a fronto-temporal network responding to multiple social categories, (2) a fronto-parietal network preferentially activated to bodies, motion, and pain, (3) a temporo-amygdalar network responding to faces, social interaction, and speech, and (4) a fronto-insular network responding to pain, emotions, social interactions, and speech. Our results highlight the role of the pSTS in processing multiple aspects of social information, as well as the feasibility and efficiency of fMRI mapping under conditions that resemble the complexity of real life.

  11. Does my brain want what my eyes like? - How food liking and choice influence spatio-temporal brain dynamics of food viewing.

    Science.gov (United States)

    Bielser, Marie-Laure; Crézé, Camille; Murray, Micah M; Toepel, Ulrike

    2016-12-01

    How food valuation and decision-making influence the perception of food is of major interest to better understand food intake behavior and, by extension, body weight management. Our study investigated behavioral responses and spatio-temporal brain dynamics by means of visual evoked potentials (VEPs) in twenty-two normal-weight participants when viewing pairs of food photographs. Participants rated how much they liked each food item (valuation) and subsequently chose between the two alternative food images. Unsurprisingly, strongly liked foods were also chosen most often. Foods were rated faster as strongly liked than as mildly liked or disliked irrespective of whether they were subsequently chosen over an alternative. Moreover, strongly liked foods were subsequently also chosen faster than the less liked alternatives. Response times during valuation and choice were positively correlated, but only when foods were liked; the faster participants rated foods as strongly liked, the faster they were in choosing the food item over an alternative. VEP modulations by the level of liking attributed as well as the subsequent choice were found as early as 135-180ms after food image onset. Analyses of neural source activity patterns over this time interval revealed an interaction between liking and the subsequent choice within the insula, dorsal frontal and superior parietal regions. The neural responses to food viewing were found to be modulated by the attributed level of liking only when foods were chosen, not when they were dismissed for an alternative. Therein, the responses to disliked foods were generally greater than those to foods that were liked more. Moreover, the responses to disliked but chosen foods were greater than responses to disliked foods which were subsequently dismissed for an alternative offer. Our findings show that the spatio-temporal brain dynamics to food viewing are immediately influenced both by how much foods are liked and by choices taken on them

  12. Differences in visual vs. verbal memory impairments as a result of focal temporal lobe damage in patients with traumatic brain injury.

    Science.gov (United States)

    Ariza, Mar; Pueyo, Roser; Junqué, Carme; Mataró, María; Poca, María Antonia; Mena, Maria Pau; Sahuquillo, Juan

    2006-09-01

    The aim of the present study was to determine whether the type of lesion in a sample of moderate and severe traumatic brain injury (TBI) was related to material-specific memory impairment. Fifty-nine patients with TBI were classified into three groups according to whether the site of the lesion was right temporal, left temporal or diffuse. Six-months post-injury, visual (Warrington's Facial Recognition Memory Test and Rey's Complex Figure Test) and verbal (Rey's Auditory Verbal Learning Test) memories were assessed. Visual memory deficits assessed by facial memory were associated with right temporal lobe lesion, whereas verbal memory performance assessed with a list of words was related to left temporal lobe lesion. The group with diffuse injury showed both verbal and visual memory impairment. These results suggest a material-specific memory impairment in moderate and severe TBI after focal temporal lesions and a non-specific memory impairment after diffuse damage.

  13. Resting-state oscillatory dynamics in sensorimotor cortex in benign epilepsy with centro-temporal spikes and typical brain development.

    Science.gov (United States)

    Koelewijn, Loes; Hamandi, Khalid; Brindley, Lisa M; Brookes, Matthew J; Routley, Bethany C; Muthukumaraswamy, Suresh D; Williams, Natalie; Thomas, Marie A; Kirby, Amanda; Te Water Naudé, Johann; Gibbon, Frances; Singh, Krish D

    2015-10-01

    Benign Epilepsy with Centro-Temporal Spikes (BECTS) is a common childhood epilepsy associated with deficits in several neurocognitive domains. Neurophysiological studies in BECTS often focus on centro-temporal spikes, but these correlate poorly with morphology and cognitive impairments. To better understand the neural profile of BECTS, we studied background brain oscillations, thought to be integrally involved in neural network communication, in sensorimotor areas. We used independent component analysis of temporally correlated sources on magnetoencephalography recordings to assess sensorimotor resting-state network activity in BECTS patients and typically developing controls. We also investigated the variability of oscillatory characteristics within focal primary motor cortex (M1), localized with a separate finger abduction task. We hypothesized that background oscillations would differ between patients and controls in the sensorimotor network but not elsewhere, especially in the beta band (13-30 Hz) because of its role in network communication and motor processing. The results support our hypothesis: in the sensorimotor network, patients had a greater variability in oscillatory amplitude compared to controls, whereas there was no difference in the visual network. Network measures did not correlate with age. The coefficient of variation of resting M1 peak frequency correlated negatively with age in the beta band only, and was greater than average for a number of patients. Our results point toward a "disorganized" functional sensorimotor network in BECTS, supporting a neurodevelopmental delay in sensorimotor cortex. Our findings further suggest that investigating the variability of oscillatory peak frequency may be a useful tool to investigate deficits of disorganization in neurodevelopmental disorders. © 2015 Wiley Periodicals, Inc.

  14. Language selection in bilinguals: a spatio-temporal analysis of electric brain activity.

    Science.gov (United States)

    Khateb, Asaid; Abutalebi, Jubin; Michel, Christoph M; Pegna, Alan J; Lee-Jahnke, Hannelore; Annoni, Jean-Marie

    2007-09-01

    Language selection refers to the cognitive mechanism that allows bilinguals to communicate in one language or the other and to switch between languages depending on the listener. Previous studies suggested that various brain areas might be involved in this process. However, the question remains whether language selection is achieved through a language-specific mechanism or through a general cognitive control process. To address this question, we compared event-related potentials (ERPs) induced by language selection and task selection processes during image naming. ERPs were collected from bilingual subjects while tested in two different contexts: a monolingual task selection context (TSc) where a post-stimulus cue instructed subjects either to name the image or generate a corresponding verb in their first language (L1), and a bilingual language selection context (LSc) where the cue indicated to name the image either in the first or the second language. By comparing the ERPs induced by the same L1 naming as a function of context, we assumed that if the selection processes varied across contexts, then electric brain responses should differ rapidly after the cue presentation. Our analysis indicated that the first ERP differences accounting for the diverging processes involved appeared between approximately 220 and 300 ms after the cue. The estimation by source localisation of brain regions accounting for these differences pointed to an increased activation during LSc in the left middle frontal-precentral gyri, supramarginal and angular gyri. Our results suggest that language selection is achieved through a neural network involving areas implicated in both general cognitive processes and language processing.

  15. Brain cells in the avian 'prefrontal cortex' code for features of slot-machine-like gambling.

    Directory of Open Access Journals (Sweden)

    Damian Scarf

    Full Text Available Slot machines are the most common and addictive form of gambling. In the current study, we recorded from single neurons in the 'prefrontal cortex' of pigeons while they played a slot-machine-like task. We identified four categories of neurons that coded for different aspects of our slot-machine-like task. Reward-Proximity neurons showed a linear increase in activity as the opportunity for a reward drew near. I-Won neurons fired only when the fourth stimulus of a winning (four-of-a-kind combination was displayed. I-Lost neurons changed their firing rate at the presentation of the first nonidentical stimulus, that is, when it was apparent that no reward was forthcoming. Finally, Near-Miss neurons also changed their activity the moment it was recognized that a reward was no longer available, but more importantly, the activity level was related to whether the trial contained one, two, or three identical stimuli prior to the display of the nonidentical stimulus. These findings not only add to recent neurophysiological research employing simulated gambling paradigms, but also add to research addressing the functional correspondence between the avian NCL and primate PFC.

  16. Spatial and Temporal Effects in Protein Post-translational Modification Distributions in the Developing Mouse Brain

    DEFF Research Database (Denmark)

    Edwards, Alistair V G; Edwards, Gregory J; Schwämmle, Veit

    2014-01-01

    Protein post-translational modification (PTM) is a powerful way to modify the behavior of cellular proteins and thereby cellular behavior. Multiple recent studies of evolutionary trends have shown that certain pairs of protein post-translational modifications tend to occur closer to each other than...... for observations of increasingly frequent and diverse protein modification in cell biology. In this study, we use mass spectrometry and proteomic strategies to present biological data showing spatiotemporal PTM co-localization across multiple PTM categories, which display changes over development of the brain...

  17. Decoupled temporal variability and signal synchronization of spontaneous brain activity in loss of consciousness: An fMRI study in anesthesia.

    Science.gov (United States)

    Huang, Zirui; Zhang, Jun; Wu, Jinsong; Qin, Pengmin; Wu, Xuehai; Wang, Zhiyao; Dai, Rui; Li, Yuan; Liang, Weimin; Mao, Ying; Yang, Zhong; Zhang, Jianfeng; Wolff, Annemarie; Northoff, Georg

    2016-01-01

    Two aspects of the low frequency fluctuations of spontaneous brain activity have been proposed which reflect the complex and dynamic features of resting-state activity, namely temporal variability and signal synchronization. The relationship between them, especially its role in consciousness, nevertheless remains unclear. Our study examined the temporal variability and signal synchronization of spontaneous brain activity, as well as their relationship during loss of consciousness. We applied an intra-subject design of resting-state functional magnetic resonance imaging (rs-fMRI) in two conditions: during wakefulness, and under anesthesia with clinical unconsciousness. In addition, an independent group of patients with disorders of consciousness (DOC) was included in order to test the reliability of our findings. We observed a global reduction in the temporal variability, local and distant brain signal synchronization for subjects during anesthesia. Importantly, we found a link between temporal variability and both local and distant signal synchronizations during wakefulness: the higher the degree of temporal variability, the higher its intra-regional homogeneity and inter-regional functional connectivity. In contrast, this link was broken down under anesthesia, implying a decoupling between temporal variability and signal synchronization; this decoupling was reproduced in patients with DOC. Our results suggest that there exist some as yet unclear physiological mechanisms of consciousness which "couple" the two mathematically independent measures, temporal variability and signal synchronization of spontaneous brain activity. Our findings not only extend our current knowledge of the neural correlates of anesthetic-induced unconsciousness, but have implications for both computational neural modeling and clinical practice, such as in the diagnosis of loss of consciousness in patients with DOC. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Temporal control of glucocorticoid neurodynamics and its relevance for brain homeostasis, neuropathology and glucocorticoid-based therapeutics.

    Science.gov (United States)

    Kalafatakis, Konstantinos; Russell, Georgina M; Zarros, Apostolos; Lightman, Stafford L

    2016-02-01

    Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Effects of sensorineural hearing loss on temporal coding of harmonic and inharmonic tone complexes in the auditory nerve.

    Science.gov (United States)

    Kale, Sushrut; Micheyl, Christophe; Heinz, Michael G

    2013-01-01

    Listeners with sensorineural hearing loss (SNHL) often show poorer thresholds for fundamental-frequency (F0) discrimination and poorer discrimination between harmonic and frequency-shifted (inharmonic) complex tones, than normal-hearing (NH) listeners-especially when these tones contain resolved or partially resolved components. It has been suggested that these perceptual deficits reflect reduced access to temporal-fine-structure (TFS) information and could be due to degraded phase locking in the auditory nerve (AN) with SNHL. In the present study, TFS and temporal-envelope (ENV) cues in single AN-fiber responses to band-pass-filtered harmonic and inharmonic complex tones were -measured in chinchillas with either normal-hearing or noise-induced SNHL. The stimuli were comparable to those used in recent psychophysical studies of F0 and harmonic/inharmonic discrimination. As in those studies, the rank of the center component was manipulated to produce -different resolvability conditions, different phase relationships (cosine and random phase) were tested, and background noise was present. Neural TFS and ENV cues were quantified using cross-correlation coefficients computed using shuffled cross correlograms between neural responses to REF (harmonic) and TEST (F0- or frequency-shifted) stimuli. In animals with SNHL, AN-fiber tuning curves showed elevated thresholds, broadened tuning, best-frequency shifts, and downward shifts in the dominant TFS response component; however, no significant degradation in the ability of AN fibers to encode TFS or ENV cues was found. Consistent with optimal-observer analyses, the results indicate that TFS and ENV cues depended only on the relevant frequency shift in Hz and thus were not degraded because phase locking remained intact. These results suggest that perceptual "TFS-processing" deficits do not simply reflect degraded phase locking at the level of the AN. To the extent that performance in F0- and harmonic/inharmonic discrimination

  20. Survival prediction using temporal muscle thickness measurements on cranial magnetic resonance images in patients with newly diagnosed brain metastases

    Energy Technology Data Exchange (ETDEWEB)

    Furtner, Julia; Prayer, Daniela [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Medical University of Vienna, Comprehensive Cancer Center, Central Nervous System Tumor Unit (CCC-CNS), Vienna (Austria); Berghoff, Anna S.; Zielinski, Christoph C.; Preusser, Matthias [Medical University of Vienna, Comprehensive Cancer Center, Central Nervous System Tumor Unit (CCC-CNS), Vienna (Austria); Medical University of Vienna, Department of Medicine I, Vienna (Austria); Albtoush, Omar M. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); University of Jordan, Department of Radiology and Nuclear Medicine, Amman (Jordan); Woitek, Ramona; Asenbaum, Ulrika [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Widhalm, Georg; Gatterbauer, Brigitte [Medical University of Vienna, Comprehensive Cancer Center, Central Nervous System Tumor Unit (CCC-CNS), Vienna (Austria); Medical University of Vienna, Department of Neurosurgery, Vienna (Austria); Dieckmann, Karin [Medical University of Vienna, Comprehensive Cancer Center, Central Nervous System Tumor Unit (CCC-CNS), Vienna (Austria); Medical University of Vienna, Department of Radiotherapy, Vienna (Austria); Birner, Peter [Medical University of Vienna, Comprehensive Cancer Center, Central Nervous System Tumor Unit (CCC-CNS), Vienna (Austria); Medical University of Vienna, Department of Medicine I, Vienna (Austria); Medical University of Vienna, Department of Pathology, Vienna (Austria); Aretin, Bernadette [General Hospital Vienna, Pharmacy Department, Vienna (Austria); Bartsch, Rupert [Medical University of Vienna, Comprehensive Cancer Center, Central Nervous System Tumor Unit (CCC-CNS), Vienna (Austria); Schoepf, Veronika [University of Graz, Institute of Psychology, Graz (Austria); BioTechMed, Graz (Austria)

    2017-08-15

    To evaluate the prognostic relevance of temporal muscle thickness (TMT) in brain metastasis patients. We retrospectively analysed TMT on magnetic resonance (MR) images at diagnosis of brain metastasis in two independent cohorts of 188 breast cancer (BC) and 247 non-small cell lung cancer (NSCLC) patients (overall: 435 patients). Survival analysis using a Cox regression model showed a reduced risk of death by 19% with every additional millimetre of baseline TMT in the BC cohort and by 24% in the NSCLC cohort. Multivariate analysis included TMT and diagnosis-specific graded prognostic assessment (DS-GPA) as covariates in the BC cohort (TMT: HR 0.791/CI [0.703-0.889]/p < 0.001; DS-GPA: HR 1.433/CI [1.160-1.771]/p = 0.001), and TMT, gender and DS-GPA in the NSCLC cohort (TMT: HR 0.710/CI [0.646-0.780]/p < 0.001; gender: HR 0.516/CI [0.387-0.687]/p < 0.001; DS-GPA: HR 1.205/CI [1.018-1.426]/p = 0.030). TMT is easily and reproducibly assessable on routine MR images and is an independent predictor of survival in patients with newly diagnosed brain metastasis from BC and NSCLC. TMT may help to better define frail patient populations and thus facilitate patient selection for therapeutic measures or clinical trials. Further prospective studies are needed to correlate TMT with other clinical frailty parameters of patients. (orig.)

  1. Temporal epilepsy lesions may be detected by the voxel-based quantitative analysis of brain FDG-PET images using an original block-matching normalization software.

    Science.gov (United States)

    Verger, Antoine; Yagdigul, Yalcin; Van Der Gucht, Axel; Poussier, Sylvain; Guedj, Eric; Maillard, Louis; Malandain, Grégoire; Hossu, Gabriela; Fay, Renaud; Karcher, Gilles; Marie, Pierre-Yves

    2016-05-01

    Statistical parametric mapping (SPM) provides useful voxel-by-voxel analyses of brain images from (18)F-fluorodesoxyglucose positron emission tomography (FDG-PET) after an initial step of spatial normalization through an anatomical template model. In the setting of the preoperative workup of patients with temporal epilepsy, this study aimed at assessing a block-matching (BM) normalization method, where most transformations are computed through small blocks, a principle that minimizes artefacts and overcomes additional image-filtering. Brain FDG-PET images from 31 patients with well-characterised temporal lobe epilepsy and among whom 22 had common mesial temporal lobe epilepsy were retrospectively analysed using both BM and conventional SPM normalization methods and with PET images from age-adjusted controls. Different threshold p values corrected for cluster volume were considered (0.01, 0.005, and 0.001). The use of BM provided equivalent values to those of SPM with regard to the overall volumes of temporal and extra-temporal hypometabolism, as well as similar sensitivity for detecting the involved temporal lobe, reaching 87 and 94 % for SPM and BM, respectively, at a threshold p value of 0.01. However, the ability to more accurately localize brain lesions within the mesial portion of the temporal lobe was a little higher with BM than with SPM with respective sensitivities reaching 78 % for BM and 45 % for SPM (p < 0.05). BM normalization compares well with conventional SPM for the voxel-based quantitative analysis of the FDG-PET images from temporal epilepsy patients. Further studies in different population are needed to determine whether BM is truly an accurate alternative to SPM in this setting.

  2. Temporal characterization of microglia/macrophage phenotypes in a mouse model of neonatal hypoxic-ischemic brain injury

    Directory of Open Access Journals (Sweden)

    Nina Hellström Erkenstam

    2016-12-01

    Full Text Available Immune cells display a high degree of phenotypic plasticity, which may facilitate their participation in both the progression and resolution of injury-induced inflammation. The purpose of this study was to investigate the temporal expression of genes associated with classical and alternative polarization phenotypes described for macrophages and to identify related cell populations in the brain following neonatal hypoxia-ischemia (HI. HI was induced in 9-day old mice and brain tissue was collected up to 7 d post-insult to investigate expression of genes associated with macrophage activation. Using cell-markers, CD86 (classic activa-tion and CD206 (alternative activation, we assessed temporal changes of CD11b+ cell populations in the brain and studied the protein expression of the immunomodulatory factor galectin-3 in these cells. HI induced a rapid regulation (6h of genes associated with both classical and alternative polarization phenotypes in the injured hemisphere. FACS analysis showed a marked increase in the number of CD11+CD86+ positive cells at 24 h after HI (+3,667 %, which was coupled with a relative suppression of CD11+CD206+ cells and cells that did not express either CD86 or CD206. The CD11+CD206+ popula-tion was mixed with some cells also expressing CD86. Confocal microscopy confirmed that a subset of cells expressed both CD86 and CD206, particularly in injured grey and white matter. Protein con-centration of galectin-3 was markedly increased mainly in the cell population lacking CD86 or CD206 in the injured hemisphere. These cells were predominantly resident microglia as very few galectin-3 positive cells co-localized with infiltrating myeloid cells in Lys-EGFP-ki mice after HI.In summary, HI was characterized by an early mixed gene response, but with a large expansion of mainly the CD86 positive population during the first day. However, the injured hemisphere also con-tained a subset of cells expressing both CD86 and CD206 and a

  3. Spatio-temporal dynamics of kind versus hostile intentions in the human brain: An electrical neuroimaging study.

    Science.gov (United States)

    Wang, Yiwen; Huang, Liang; Zhang, Wei; Zhang, Zhen; Cacioppo, Stephanie

    2015-01-01

    Neuroscience research suggests that inferring neutral intentions of other people recruits a specific brain network within the inferior fronto-parietal action observation network as well as a putative social network including brain areas subserving theory of mind, such as the posterior superior temporal sulcus (pSTS), the temporo-parietal junction (TPJ), and also the anterior cingulate cortex (ACC). Recent studies on harmful intentions have refined this network by showing the specific involvement of the ACC, amygdala, and ventromedial prefrontal cortex (vmPFC) in early stages (within 200 ms) of information processing. However, the functional dynamics for kind intentions within and among these networks remains unclear. To address this question, we measured electrical brain activity from 18 healthy adult participants while they were performing an intention inference task with three different types of intentions: kind, hostile and non-interactive. Electrophysiological results revealed that kind intentions were characterized by significantly larger peak amplitudes of N2 over the frontal sites than those for hostile and non-interactive intentions. On the other hand, there were no significant differences between hostile and non-interactive intentions at N2. The source analysis suggested that the vicinity of the left cingulate gyrus contributed to the N2 effect by subtracting the kindness condition from the non-interactive condition within 250-350 ms. At a later stage (i.e., during the 270-500 ms epoch), the peak amplitude of the P3 over the parietal sites and the right hemisphere was significantly larger for hostile intentions compared to the kind and non-interactive intentions. No significant differences were observed at P3 between kind and non-interactive intentions. The source analysis showed that the vicinity of the left anterior cingulate cortex contributed to the P3 effect by subtracting the hostility condition from the non-interactive condition within 450-550 ms

  4. Ictal {sup 99m}Tc-ECD brain SPECT imaging: localization of seizure foci and correlation with semiology in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Do Young; Ryu, Jin Sook; Lee, Hee Kyung; Ma, Hyeo Il; Lee, Sang Ahm; Lee, Jung Kyo; Kang, Joong Koo [Asan Medical Center, Seoul (Korea, Republic of)

    1997-07-01

    The purpose of this study was to evaluate the usefulness of ictal {sup 99m}Tc-ECD brain SPECT in temporal lobe epilepsy (TLE) patients for presurgical localization of seizure foci, and to correlate ictal SPECT patterns with the semiology of seizure. ictal {sup 99m}Tc-ECD Brain SPECT was performed in 23 TLE patients whose MRI showed unilateral hippocampal atrophy (18 patients), other focal temporal lesions (4 patients) and normal finding (1 patient). Under CCTV monitoring, injection was done during ictal period in all patients with the mean delay of 38.5{+-}17.3 sec (mean seizure duration : 90.5{+-}35.9 sec). Ictal {sup 99m}Tc-ECD Brain SPECT was visually analysed by three blinded observers. All patients underwent temporal lobectomy with a minimum 3 months follow-up (range 3-29 months) ; all had good post-surgical seizure control (Engel's calssification class I). Ictal {sup 99m}Tc-ECD Brain SPECT showed unilateral temporal hyperperfusion concordant with epileptic foci in 22/23 (95.7%), whereas non-lateralization in 1/23 (4.3%). The hyperperfusion of the ipsilateral basal ganglia was present in 72.7% (16/22) of patients with dystonic/tonic posture of the contralateral hand. The contralateral cerebellar hyperperfusion was observed in the 7/22 (32%). The group with secondary generalized tonic clonic seizure (GTC) had brain stem and bilateral thalamic hyperperfusion in 4/7 (57.1%) while the group without secondary GTC had the same hyperperfusion in 1/16 (6.3%). There was statistically significant difference in brain stem and bilateral thalamic perfusion between two groups. Ictal {sup 99m}Tc-ECD Brain SPECT is a useful modality in pre-surgical localization of the epileptic foci and well correlated with the semiology of seizure.

  5. Decoding the encoding of functional brain networks: An fMRI classification comparison of non-negative matrix factorization (NMF), independent component analysis (ICA), and sparse coding algorithms.

    Science.gov (United States)

    Xie, Jianwen; Douglas, Pamela K; Wu, Ying Nian; Brody, Arthur L; Anderson, Ariana E

    2017-04-15

    Brain networks in fMRI are typically identified using spatial independent component analysis (ICA), yet other mathematical constraints provide alternate biologically-plausible frameworks for generating brain networks. Non-negative matrix factorization (NMF) would suppress negative BOLD signal by enforcing positivity. Spatial sparse coding algorithms (L1 Regularized Learning and K-SVD) would impose local specialization and a discouragement of multitasking, where the total observed activity in a single voxel originates from a restricted number of possible brain networks. The assumptions of independence, positivity, and sparsity to encode task-related brain networks are compared; the resulting brain networks within scan for different constraints are used as basis functions to encode observed functional activity. These encodings are then decoded using machine learning, by using the time series weights to predict within scan whether a subject is viewing a video, listening to an audio cue, or at rest, in 304 fMRI scans from 51 subjects. The sparse coding algorithm of L1 Regularized Learning outperformed 4 variations of ICA (pICA and sparse coding algorithms. Holding constant the effect of the extraction algorithm, encodings using sparser spatial networks (containing more zero-valued voxels) had higher classification accuracy (pICA. Negative BOLD signal may capture task-related activations. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Resting-state fMRI revealed different brain activities responding to valproic acid and levetiracetam in benign epilepsy with central-temporal spikes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qirui; Zhang, Zhiqiang; Xu, Qiang; Wu, Han; Li, Zhipeng; Lu, Guangming [Nanjing University School of Medicine, Department of Medical Imaging, Jinling Hospital, Nanjing (China); Yang, Fang; Li, Qian [Nanjing University School of Medicine, Department of Neurology, Jinling Hospital, Nanjing (China); Hu, Zheng [Nanjing Children' s Hospital, Department of Neurology, Nanjing (China); Dante, Mantini [Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven (Belgium); Li, Kai [Suzhou University, Laboratory of Molecular Medicine, Suzhou (China)

    2017-05-15

    Our aim was to investigate regional difference in brain activities in response to antiepileptic drug (AED) medications in benign epilepsy with central-temporal spikes (BECTS) using resting-state functional magnetic resonance imaging (fMRI). Fifty-seven patients with BECTS underwent resting-state fMRI scans after receiving either valproic acid (VPA) (n = 15), levetiracetam (LEV) (n = 21), or no medication (n = 21). fMRI regional homogeneity (ReHo) parameter among the three groups of patients were compared and were correlated with total doses of AED in the two medicated groups. Compared with patients on no-medication, patients receiving either VPA or LEV showed decreased ReHo in the central-temporal region, frontal cortex, and thalamus. In particular, the VPA group showed greater ReHo decrease in the thalamus and milder in cortices and caudate heads compared with the LEV group. In addition, the VPA group demonstrated a negative correlation between ReHo values in the central-temporal region and medication dose. Both VPA and LEV inhibit resting-state neural activity in the central-temporal region, which is the main epileptogenic focus of BECTS. VPA reduced brain activity in the cortical epileptogenic regions and thalamus evenly, whereas LEV reduced brain activity predominantly in the cortices. Interestingly, VPA showed a cumulative effect on inhibiting brain activity in the epileptogenic regions in BECTS. (orig.)

  7. Dual Temporal and Spatial Sparse Representation for Inferring Group-wise Brain Networks from Resting-state fMRI Dataset.

    Science.gov (United States)

    Gong, Junhui; Liu, Xiaoyan; Liu, Tianming; Zhou, Jiansong; Sun, Gang; Tian, Juanxiu

    2017-08-09

    Recently, sparse representation has been successfully used to identify brain networks from task-based fMRI dataset. However, when using the strategy to analyze resting-state fMRI dataset, it is still a challenge to automatically infer the group-wise brain networks under consideration of group commonalities and subject-specific characteristics. In the paper, a novel method based on dual temporal and spatial sparse representation (DTSSR) is proposed to meet this challenge. Firstly, the brain functional networks with subject-specific characteristics are obtained via sparse representation with online dictionary learning for the fMRI time series (temporal domain) of each subject. Next, based on the current brain science knowledge, a simple mathematical model is proposed to describe the complex nonlinear dynamic coupling mechanism of the brain networks, with which the group-wise intrinsic connectivity networks (ICNs) can be inferred by sparse representation for these brain functional networks (spatial domain) of all subjects. Experiments on Leiden_2180 dataset show that most group-wise ICNs obtained by the proposed DTSSR are interpretable by current brain science knowledge and are consistent with previous literature reports. The robustness of DTSSR and the reproducibility of the results are demonstrated by experiments on three different datasets (Leiden_2180, Leiden_2200 and our own dataset). Results of the present work shed new light on exploring the coupling mechanism of BFNs from perspective of information science.

  8. Striatal and Tegmental Neurons Code Critical Signals for Temporal-Difference Learning of State Value in Domestic Chicks.

    Science.gov (United States)

    Wen, Chentao; Ogura, Yukiko; Matsushima, Toshiya

    2016-01-01

    To ensure survival, animals must update the internal representations of their environment in a trial-and-error fashion. Psychological studies of associative learning and neurophysiological analyses of dopaminergic neurons have suggested that this updating process involves the temporal-difference (TD) method in the basal ganglia network. However, the way in which the component variables of the TD method are implemented at the neuronal level is unclear. To investigate the underlying neural mechanisms, we trained domestic chicks to associate color cues with food rewards. We recorded neuronal activities from the medial striatum or tegmentum in a freely behaving condition and examined how reward omission changed neuronal firing. To compare neuronal activities with the signals assumed in the TD method, we simulated the behavioral task in the form of a finite sequence composed of discrete steps of time. The three signals assumed in the simulated task were the prediction signal, the target signal for updating, and the TD-error signal. In both the medial striatum and tegmentum, the majority of recorded neurons were categorized into three types according to their fitness for three models, though these neurons tended to form a continuum spectrum without distinct differences in the firing rate. Specifically, two types of striatal neurons successfully mimicked the target signal and the prediction signal. A linear summation of these two types of striatum neurons was a good fit for the activity of one type of tegmental neurons mimicking the TD-error signal. The present study thus demonstrates that the striatum and tegmentum can convey the signals critically required for the TD method. Based on the theoretical and neurophysiological studies, together with tract-tracing data, we propose a novel model to explain how the convergence of signals represented in the striatum could lead to the computation of TD error in tegmental dopaminergic neurons.

  9. Striatal and Tegmental Neurons Code Critical Signals for Temporal-Difference Learning of State Value in Domestic Chicks

    Directory of Open Access Journals (Sweden)

    Chentao Wen

    2016-11-01

    Full Text Available To ensure survival, animals must update the internal representations of their environment in a trial-and-error fashion. Psychological studies of associative learning and neurophysiological analyses of dopaminergic neurons have suggested that this updating process involves the temporal-difference (TD method in the basal ganglia network. However, the way in which the component variables of the TD method are implemented at the neuronal level is unclear. To investigate the underlying neural mechanisms, we trained domestic chicks to associate color cues with food rewards. We recorded neuronal activities from the medial striatum or tegmentum in a freely behaving condition and examined how reward omission changed neuronal firing. To compare neuronal activities with the signals assumed in the TD method, we simulated the behavioral task in the form of a finite sequence composed of discrete steps of time. The three signals assumed in the simulated task were the prediction signal, the target signal for updating, and the TD-error signal. In both the medial striatum and tegmentum, the majority of recorded neurons were categorized into three types according to their fitness for three models, though these neurons tended to form a continuum spectrum without distinct differences in the firing rate. Specifically, two types of striatal neurons successfully mimicked the target signal and the prediction signal. A linear summation of these two types of striatum neurons was a good fit for the activity of one type of tegmental neurons mimicking the TD-error signal. The present study thus demonstrates that the striatum and tegmentum can convey the signals critically required for the TD method. Based on the theoretical and neurophysiological studies, together with tract-tracing data, we propose a novel model to explain how the convergence of signals represented in the striatum could lead to the computation of TD error in tegmental dopaminergic neurons.

  10. Diagnosis and temporal evolution of signs of intracranial hypotension on MRI of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Forghani, R. [McGill University Health Center, Department of Radiology, Montreal, Que (Canada); Massachusetts General Hospital, Division of Neuroradiology, Boston, MA (United States); Farb, R.I. [University of Toronto, Department of Medical Imaging, Division of Neuroradiology, Toronto Western Hospital, Toronto, Ontario (Canada)

    2008-12-15

    A comprehensive evaluation of cranial magnetic resonance imagings (MRIs) of 23 patients with intracranial hypotension (IH) was performed, and the evolution of the abnormalities on follow-up MRIs was correlated with the clinical outcome. The MRI report database at the University Health Network in Toronto was searched, and 23 cases of IH were identified between 2001 and 2007. A retrospective review of the MRIs of the brain and the electronic patient chart was performed. A control group of 40 subjects was also selected to complement the analysis of the pituitary gland. A positive venous distention sign (VDS) was observed in 23 out of 23 patients and was the first sign to disappear on early follow-up scans following successful treatment. Pachymeningeal enhancement was seen in 23 out of 23 patients, and pachymeningeal thickening was detectable on unenhanced fluid attenuation inversion recovery (FLAIR) sequences in 17 out of 23 patients (74%). An increase in pituitary size in IH was also demonstrated based on the measured pituitary height and was qualitatively detectable in 12 out of 21 (57%) patients as the protrusion of the pituitary gland above the sella turica (two postpartum patients were excluded from this analysis). Overall, there was good correlation between the imaging findings and clinical outcome following treatment. Accurate diagnosis and follow-up of IH should be possible is some patients on unenhanced MRI of the brain by combining the signs on FLAIR and sagittal T1W images, enabling timely diagnosis in unsuspected cases and avoiding unnecessary administration of gadolinium compounds. In addition, VDS might be useful for early assessment of response to treatment. (orig.)

  11. High-frequency combination coding-based steady-state visual evoked potential for brain computer interface

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng; Zhang, Xin; Xie, Jun; Li, Yeping; Han, Chengcheng; Lili, Li; Wang, Jing [School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xu, Guang-Hua [School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710054 (China)

    2015-03-10

    This study presents a new steady-state visual evoked potential (SSVEP) paradigm for brain computer interface (BCI) systems. The goal of this study is to increase the number of targets using fewer stimulation high frequencies, with diminishing subject’s fatigue and reducing the risk of photosensitive epileptic seizures. The new paradigm is High-Frequency Combination Coding-Based High-Frequency Steady-State Visual Evoked Potential (HFCC-SSVEP).Firstly, we studied SSVEP high frequency(beyond 25 Hz)response of SSVEP, whose paradigm is presented on the LED. The SNR (Signal to Noise Ratio) of high frequency(beyond 40 Hz) response is very low, which is been unable to be distinguished through the traditional analysis method; Secondly we investigated the HFCC-SSVEP response (beyond 25 Hz) for 3 frequencies (25Hz, 33.33Hz, and 40Hz), HFCC-SSVEP produces n{sup n} with n high stimulation frequencies through Frequence Combination Code. Further, Animproved Hilbert-huang transform (IHHT)-based variable frequency EEG feature extraction method and a local spectrum extreme target identification algorithmare adopted to extract time-frequency feature of the proposed HFCC-SSVEP response.Linear predictions and fixed sifting (iterating) 10 time is used to overcome the shortage of end effect and stopping criterion,generalized zero-crossing (GZC) is used to compute the instantaneous frequency of the proposed SSVEP respondent signals, the improved HHT-based feature extraction method for the proposed SSVEP paradigm in this study increases recognition efficiency, so as to improve ITR and to increase the stability of the BCI system. what is more, SSVEPs evoked by high-frequency stimuli (beyond 25Hz) minimally diminish subject’s fatigue and prevent safety hazards linked to photo-induced epileptic seizures, So as to ensure the system efficiency and undamaging.This study tests three subjects in order to verify the feasibility of the proposed method.

  12. Alteration of interictal brain activity in patients with temporal lobe epilepsy in the left dominant hemisphere: a resting-state MEG study.

    Science.gov (United States)

    Zhu, Haitao; Zhu, Jinlong; Zhao, Tiezhu; Wu, Yong; Liu, Hongyi; Wu, Ting; Yang, Lu; Zou, Yuanjie; Zhang, Rui; Zheng, Gang

    2014-01-01

    Resting MEG activities were compared between patients with left temporal lobe epilepsy (LTLE) and normal controls. Using SAMg2, the activities of MEG data were reconstructed and normalized. Significantly elevated SAMg2 signals were found in LTLE patients in the left temporal lobe and medial structures. Marked decreases of SAMg2 signals were found in the wide extratemporal lobe regions, such as the bilateral visual cortex. The study also demonstrated a positive correlation between the seizure frequency and brain activities of the abnormal regions after the multiple linear regression analysis. These results suggested that the aberrant brain activities not only were related to the epileptogenic zones, but also existed in other extratemporal regions in patients with LTLE. The activities of the aberrant regions could be further damaged with the increase of the seizure frequency. Our findings indicated that LTLE could be a multifocal disease, including complex epileptic networks and brain dysfunction networks.

  13. Alteration of Interictal Brain Activity in Patients with Temporal Lobe Epilepsy in the Left Dominant Hemisphere: A Resting-State MEG Study

    Directory of Open Access Journals (Sweden)

    Haitao Zhu

    2014-01-01

    Full Text Available Resting MEG activities were compared between patients with left temporal lobe epilepsy (LTLE and normal controls. Using SAMg2, the activities of MEG data were reconstructed and normalized. Significantly elevated SAMg2 signals were found in LTLE patients in the left temporal lobe and medial structures. Marked decreases of SAMg2 signals were found in the wide extratemporal lobe regions, such as the bilateral visual cortex. The study also demonstrated a positive correlation between the seizure frequency and brain activities of the abnormal regions after the multiple linear regression analysis. These results suggested that the aberrant brain activities not only were related to the epileptogenic zones, but also existed in other extratemporal regions in patients with LTLE. The activities of the aberrant regions could be further damaged with the increase of the seizure frequency. Our findings indicated that LTLE could be a multifocal disease, including complex epileptic networks and brain dysfunction networks.

  14. Neuroinflammation, myelin and behavior: Temporal patterns following mild traumatic brain injury in mice.

    Directory of Open Access Journals (Sweden)

    Toufik Taib

    Full Text Available Traumatic brain injury (TBI results in white matter injury (WMI that is associated with neurological deficits. Neuroinflammation originating from microglial activation may participate in WMI and associated disorders. To date, there is little information on the time courses of these events after mild TBI. Therefore we investigated (i neuroinflammation, (ii WMI and (iii behavioral disorders between 6 hours and 3 months after mild TBI. For that purpose, we used experimental mild TBI in mice induced by a controlled cortical impact. (i For neuroinflammation, IL-1b protein as well as microglial phenotypes, by gene expression for 12 microglial activation markers on isolated CD11b+ cells from brains, were studied after TBI. IL-1b protein was increased at 6 hours and 1 day. TBI induced a mixed population of microglial phenotypes with both pro-inflammatory, anti-inflammatory and immunomodulatory markers from 6 hours to 3 days post-injury. At 7 days, microglial activation was completely resolved. (ii Three myelin proteins were assessed after TBI on ipsi- and contralateral corpus callosum, as this structure is enriched in white matter. TBI led to an increase in 2',3'-cyclic-nucleotide 3'-phosphodiesterase, a marker of immature and mature oligodendrocyte, at 2 days post-injury; a bilateral demyelination, evaluated by myelin basic protein, from 7 days to 3 months post-injury; and an increase in myelin oligodendrocyte glycoprotein at 6 hours and 3 days post-injury. Transmission electron microscopy study revealed various myelin sheath abnormalities within the corpus callosum at 3 months post-TBI. (iii TBI led to sensorimotor deficits at 3 days post-TBI, and late cognitive flexibility disorder evidenced by the reversal learning task of the Barnes maze 3 months after injury. These data give an overall invaluable overview of time course of neuroinflammation that could be involved in demyelination and late cognitive disorder over a time-scale of 3 months in a model

  15. Neuroinflammation, myelin and behavior: Temporal patterns following mild traumatic brain injury in mice

    Science.gov (United States)

    Taib, Toufik; Leconte, Claire; Van Steenwinckel, Juliette; Cho, Angelo H.; Palmier, Bruno; Torsello, Egle; Lai Kuen, Rene; Onyeomah, Somfieme; Ecomard, Karine; Benedetto, Chiara; Coqueran, Bérard; Novak, Anne-Catherine; Deou, Edwige; Plotkine, Michel; Gressens, Pierre; Marchand-Leroux, Catherine

    2017-01-01

    Traumatic brain injury (TBI) results in white matter injury (WMI) that is associated with neurological deficits. Neuroinflammation originating from microglial activation may participate in WMI and associated disorders. To date, there is little information on the time courses of these events after mild TBI. Therefore we investigated (i) neuroinflammation, (ii) WMI and (iii) behavioral disorders between 6 hours and 3 months after mild TBI. For that purpose, we used experimental mild TBI in mice induced by a controlled cortical impact. (i) For neuroinflammation, IL-1b protein as well as microglial phenotypes, by gene expression for 12 microglial activation markers on isolated CD11b+ cells from brains, were studied after TBI. IL-1b protein was increased at 6 hours and 1 day. TBI induced a mixed population of microglial phenotypes with both pro-inflammatory, anti-inflammatory and immunomodulatory markers from 6 hours to 3 days post-injury. At 7 days, microglial activation was completely resolved. (ii) Three myelin proteins were assessed after TBI on ipsi- and contralateral corpus callosum, as this structure is enriched in white matter. TBI led to an increase in 2',3'-cyclic-nucleotide 3'-phosphodiesterase, a marker of immature and mature oligodendrocyte, at 2 days post-injury; a bilateral demyelination, evaluated by myelin basic protein, from 7 days to 3 months post-injury; and an increase in myelin oligodendrocyte glycoprotein at 6 hours and 3 days post-injury. Transmission electron microscopy study revealed various myelin sheath abnormalities within the corpus callosum at 3 months post-TBI. (iii) TBI led to sensorimotor deficits at 3 days post-TBI, and late cognitive flexibility disorder evidenced by the reversal learning task of the Barnes maze 3 months after injury. These data give an overall invaluable overview of time course of neuroinflammation that could be involved in demyelination and late cognitive disorder over a time-scale of 3 months in a model of mild TBI

  16. Syllabic encoding during overt speech production in Cantonese: Evidence from temporal brain responses.

    Science.gov (United States)

    Wong, Andus Wing-Kuen; Wang, Jie; Ng, Tin-Yan; Chen, Hsuan-Chih

    2016-10-01

    The time course of phonological encoding in overt Cantonese disyllabic word production was investigated using a picture-word interference task with concurrent recording of the event-related brain potentials (ERPs). Participants were asked to name aloud individually presented pictures and ignore a distracting Chinese character. Participants' naming responses were faster, relative to an unrelated control, when the distractor overlapped with the target's word-initial or word-final syllables. Furthermore, ERP waves in the syllable-related conditions were more positive-going than those in the unrelated control conditions from 500ms to 650ms post target onset (i.e., a late positivity). The mean and peak amplitudes of this late positivity correlated with the size of phonological facilitation. More importantly, the onset of the late positivity associated with word-initial syllable priming was 44ms earlier than that associated with word-final syllable priming, suggesting that phonological encoding in overt speech runs incrementally and the encoding duration for one syllable unit is approximately 44ms. Although the size of effective phonological units might vary across languages, as suggested by previous speech production studies, the present data indicate that the incremental nature of phonological encoding is a universal mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Automatic interpretation of F-18-FDG brain PET using artificial neural network: discrimination of medial and lateral temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Sung; Lee, Dong Soo; Kim, Seok Ki; Park, Kwang Suk; Lee, Sang Kun; Chung, June Key; Lee, Myung Chul [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2004-06-01

    We developed a computer-aided classifier using artificial neural network (ANN) to discriminate the cerebral metabolic pattern of medial and lateral temporal lobe epilepsy (TLE). We studied brain F-18-FDG PET images of 113 epilepsy patients surgically and pathologically proven as medial TLE (left 41, right 42) or lateral TLE (left 14, right 16). PET images were spatially transformed onto a standard template and normalized to the mean counts of cortical regions. Asymmetry indices for predefined 17 mirrored regions to hemispheric midline and those for medial and lateral temporal lobes were used as input features for ANN. ANN classifier was composed of 3 independent multi-layered perceptions (1 for left/right lateralization and 2 for medial/lateral discrimination) and trained to interpret metabolic patterns and produce one of 4 diagnoses (L/R medial TLE or L/R lateral TLE). Randomly selected 8 images from each group were used to train the ANN classifier and remaining 81 images were used as test sets. The accuracy of the diagnosis with ANN was estimated by averaging the agreement rates of independent 50 trials and compared to that of nuclear medicine experts. The accuracy in lateralization was 89% by the human experts and 90% by the ANN classifier. Overall accuracy in localization of epileptogenic zones by the ANN classifier was 69%, which was comparable to that by the human experts (72%). We conclude that ANN classifier performed as well as human experts and could be potentially useful supporting tool for the differential diagnosis of TLE.

  18. Presurgery resting-state local graph-theory measures predict neurocognitive outcomes after brain surgery in temporal lobe epilepsy.

    Science.gov (United States)

    Doucet, Gaelle E; Rider, Robert; Taylor, Nathan; Skidmore, Christopher; Sharan, Ashwini; Sperling, Michael; Tracy, Joseph I

    2015-04-01

    This study determined the ability of resting-state functional connectivity (rsFC) graph-theory measures to predict neurocognitive status postsurgery in patients with temporal lobe epilepsy (TLE) who underwent anterior temporal lobectomy (ATL). A presurgical resting-state functional magnetic resonance imaging (fMRI) condition was collected in 16 left and 16 right TLE patients who underwent ATL. In addition, patients received neuropsychological testing pre- and postsurgery in verbal and nonverbal episodic memory, language, working memory, and attention domains. Regarding the functional data, we investigated three graph-theory properties (local efficiency, distance, and participation), measuring segregation, integration and centrality, respectively. These measures were only computed in regions of functional relevance to the ictal pathology, or the cognitive domain. Linear regression analyses were computed to predict the change in each neurocognitive domain. Our analyses revealed that cognitive outcome was successfully predicted with at least 68% of the variance explained in each model, for both TLE groups. The only model not significantly predictive involved nonverbal episodic memory outcome in right TLE. Measures involving the healthy hippocampus were the most common among the predictors, suggesting that enhanced integration of this structure with the rest of the brain may improve cognitive outcomes. Regardless of TLE group, left inferior frontal regions were the best predictors of language outcome. Working memory outcome was predicted mostly by right-sided regions, in both groups. Overall, the results indicated our integration measure was the most predictive of neurocognitive outcome. In contrast, our segregation measure was the least predictive. This study provides evidence that presurgery rsFC measures may help determine neurocognitive outcomes following ATL. The results have implications for refining our understanding of compensatory reorganization and predicting

  19. Early and late age of seizure onset have a differential impact on brain resting-state organization in temporal lobe epilepsy.

    Science.gov (United States)

    Doucet, Gaëlle E; Sharan, Ashwini; Pustina, Dorian; Skidmore, Christopher; Sperling, Michael R; Tracy, Joseph I

    2015-01-01

    Temporal lobe epilepsy (TLE) is associated with abnormalities which extend into the entire brain. While the age of seizure onset (SO) has a large impact on brain plasticity, its effect on brain connectivity at rest remains unclear, especially, in interaction with factors such as the presence of mesial temporal sclerosis (MTS). In this context, we investigated whole-brain and regional functional connectivity (FC) organization in 50 TLE patients who underwent a resting-state fMRI scan, in comparison to healthy controls, using graph-theory measures. We first classified TLE patients according to the presence of MTS or not. Then, we categorized the patients based on their age of SO into two subgroups (early or late age of SO). Results revealed whole-brain differences with both reduced functional segregation and increased integration in the patients, regardless of the age of SO and MTS, relative to the controls. At a local level, we revealed that the connectivity of the ictal hippocampus remains the most impaired for an early SO, even in the absence of MTS. Importantly, we showed that the impact of age of SO on whole-brain and regional resting-state FC depends on the presence of MTS. Overall, our results highlight the importance of investigating the effect of age of SO when examining resting-state activity in TLE, as this factor leads different perturbations of network modularity and connectivity at the global and local level, with different implications for regional plasticity and adaptive organization.

  20. Insights into Intrinsic Brain Networks based on Graph Theory and PET in right- compared to left-sided Temporal Lobe Epilepsy.

    Science.gov (United States)

    Vanicek, Thomas; Hahn, Andreas; Traub-Weidinger, Tatjana; Hilger, Eva; Spies, Marie; Wadsak, Wolfgang; Lanzenberger, Rupert; Pataraia, Ekaterina; Asenbaum-Nan, Susanne

    2016-06-28

    The human brain exhibits marked hemispheric differences, though it is not fully understood to what extent lateralization of the epileptic focus is relevant. Preoperative [(18)F]FDG-PET depicts lateralization of seizure focus in patients with temporal lobe epilepsy and reveals dysfunctional metabolic brain connectivity. The aim of the present study was to compare metabolic connectivity, inferred from inter-regional [(18)F]FDG PET uptake correlations, in right-sided (RTLE; n = 30) and left-sided TLE (LTLE; n = 32) with healthy controls (HC; n = 31) using graph theory based network analysis. Comparing LTLE and RTLE and patient groups separately to HC, we observed higher lobar connectivity weights in RTLE compared to LTLE for connections of the temporal and the parietal lobe of the contralateral hemisphere (CH). Moreover, especially in RTLE compared to LTLE higher local efficiency were found in the temporal cortices and other brain regions of the CH. The results of this investigation implicate altered metabolic networks in patients with TLE specific to the lateralization of seizure focus, and describe compensatory mechanisms especially in the CH of patients with RTLE. We propose that graph theoretical analysis of metabolic connectivity using [(18)F]FDG-PET offers an important additional modality to explore brain networks.

  1. High Frequency Burst Firing of Granule Cells Ensures Transmission at the Parallel Fiber to Purkinje Cell Synapse at the Cost of Temporal Coding.

    Directory of Open Access Journals (Sweden)

    Boeke Job van Beugen

    2013-05-01

    Full Text Available Cerebellar granule cells (GrCs convey information from mossy fibers (MFs to Purkinje cells (PCs via their parallel fibers (PFs. MF to GrC signaling allows transmission of frequencies up to 1 kHz and GrCs themselves can also fire bursts of action potentials with instantaneous frequencies up to 1 kHz. So far, in the scientific literature no evidence has been shown that these high-frequency bursts also exist in awake, behaving animals. More so, it remains to be shown whether such high-frequency bursts can transmit temporally coded information from MFs to PCs and/or whether these patterns of activity contribute to the spatiotemporal filtering properties of the granule cell layer. Here, we show that, upon sensory stimulation both in un-anesthetized rabbits and mice, GrCs can show bursts that consist of tens of spikes at instantaneous frequencies over 800 Hz. In vitro recordings from individual GrC-PC pairs following high-frequency stimulation revealed an overall low initial release probability of ~0.17. Nevertheless, high-frequency burst activity induced a short-lived facilitation to ensure signaling within the first few spikes, which was rapidly followed by a reduction in transmitter release to prevent immediate postsynaptic saturation. The facilitation rate among individual GrC-PC pairs was heterogeneously distributed and could be classified as either ‘reluctant’ or ‘responsive’ according to their release characteristics. Despite the variety of efficacy at individual connections, grouped activity in GrCs resulted in a linear relationship between PC response and PF burst duration at frequencies up to 300 Hz allowing rate coding to persist at the network level. Together, these findings support the hypothesis that the cerebellar granular layer acts as a spatiotemporal filter between MF input and PC output (D’Angelo and De Zeeuw, 2009.

  2. Effects of medial temporal lobe degeneration on brain perfusion in amnestic MCI of AD type: deafferentation and functional compensation?

    Energy Technology Data Exchange (ETDEWEB)

    Guedj, Eric [Centre Hospitalo-Universitaire de la Timone, Service Central de Biophysique et de Medecine Nucleaire, Marseille Cedex 5 (France); Universite de la Mediterranee Aix-Marseille II, Laboratoire de Neurophysiologie et Neuropsychologie, Inserm U751, Faculte de Medecine, Marseille (France); Universite de la Mediterranee Aix-Marseille II, Centre de Resonance Magnetique Biologique et Medicale (CRMBM), UMR CNRS 6612, Faculte de Medecine, Marseille (France); Barbeau, Emmanuel J. [CNRS - Universite Paul Sabatier Toulouse 3, Centre de Recherche Cerveau et Cognition, UMR-5549, Toulouse (France); Didic, Mira; Poncet, Michel; Ceccaldi, Mathieu [CHU Timone, Service de Neurologie et de Neuropsychologie, Marseille (France); Universite de la Mediterranee Aix-Marseille II, Laboratoire de Neurophysiologie et Neuropsychologie, Inserm U751, Faculte de Medecine, Marseille (France); Felician, Olivier [CHU Timone, Service de Neurologie et de Neuropsychologie, Marseille (France); Universite de la Mediterranee Aix-Marseille II, Laboratoire de Neurophysiologie et Neuropsychologie, Inserm U751, Faculte de Medecine, Marseille (France); Centre Saint-Charles, Laboratoire de Neurobiologie Integrative et Adaptative, UMR CNRS 6149, Marseille (France); Laforte, Catherine de; Mundler, Olivier [Centre Hospitalo-Universitaire de la Timone, Service Central de Biophysique et de Medecine Nucleaire, Marseille Cedex 5 (France); Ranjeva, Jean-Philippe; Cozzone, Patrick J. [Universite de la Mediterranee Aix-Marseille II, Centre de Resonance Magnetique Biologique et Medicale (CRMBM), UMR CNRS 6612, Faculte de Medecine, Marseille (France)

    2009-07-15

    Cortical atrophy is correlated with the progression of neuropathological lesions within the medial temporal lobes (MTL) in Alzheimer's disease (AD). Our aim was to determine which local and remote functional changes result from MTL volume loss at the predementia stage. We studied the relationship between entorhinal and hippocampal MR volumes and whole-brain SPECT perfusion via a voxel-based correlative analysis in 19 patients with amnestic mild cognitive impairment with a memory profile suggestive of early AD. Right MTL volumes were positively correlated with remote posterior perfusion of the posterior cingulate cortex, and negatively correlated with remote anterior perfusion of the right medial and dorsolateral prefrontal cortex. There was no local correlation between volumes and perfusion within the MTL. These findings provide further insight into functional changes that result from MTL volume loss during the predementia stage of AD. The positive correlation between MTL volumes and posterior cingulate perfusion may reflect the deafferentation of a temporocingulate network due to mediotemporal degeneration. The paradoxical negative correlation between MTL volumes and prefrontal perfusion may result from recruitment of an alternative anterior temporofrontal network. It remains to be investigated how the ''net sum'' of this perfusion modulation affects memory and other cognitive domains through a possible compensatory perspective. (orig.)

  3. Temporal evolution of brain reorganization under cross-modal training: insights into the functional architecture of encoding and retrieval networks

    Science.gov (United States)

    Likova, Lora T.

    2015-03-01

    This study is based on the recent discovery of massive and well-structured cross-modal memory activation generated in the primary visual cortex (V1) of totally blind people as a result of novel training in drawing without any vision (Likova, 2012). This unexpected functional reorganization of primary visual cortex was obtained after undergoing only a week of training by the novel Cognitive-Kinesthetic Method, and was consistent across pilot groups of different categories of visual deprivation: congenitally blind, late-onset blind and blindfolded (Likova, 2014). These findings led us to implicate V1 as the implementation of the theoretical visuo-spatial 'sketchpad' for working memory in the human brain. Since neither the source nor the subsequent 'recipient' of this non-visual memory information in V1 is known, these results raise a number of important questions about the underlying functional organization of the respective encoding and retrieval networks in the brain. To address these questions, an individual totally blind from birth was given a week of Cognitive-Kinesthetic training, accompanied by functional magnetic resonance imaging (fMRI) both before and just after training, and again after a two-month consolidation period. The results revealed a remarkable temporal sequence of training-based response reorganization in both the hippocampal complex and the temporal-lobe object processing hierarchy over the prolonged consolidation period. In particular, a pattern of profound learning-based transformations in the hippocampus was strongly reflected in V1, with the retrieval function showing massive growth as result of the Cognitive-Kinesthetic memory training and consolidation, while the initially strong hippocampal response during tactile exploration and encoding became non-existent. Furthermore, after training, an alternating patch structure in the form of a cascade of discrete ventral regions underwent radical transformations to reach complete functional

  4. Human fetal brain-derived neural stem/progenitor cells grafted into the adult epileptic brain restrain seizures in rat models of temporal lobe epilepsy.

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    Lee, Haejin; Yun, Seokhwan; Kim, Il-Sun; Lee, Il-Shin; Shin, Jeong Eun; Park, Soo Chul; Kim, Won-Joo; Park, Kook In

    2014-01-01

    Cell transplantation has been suggested as an alternative therapy for temporal lobe epilepsy (TLE) because this can suppress spontaneous recurrent seizures in animal models. To evaluate the therapeutic potential of human neural stem/progenitor cells (huNSPCs) for treating TLE, we transplanted huNSPCs, derived from an aborted fetal telencephalon at 13 weeks of gestation and expanded in culture as neurospheres over a long time period, into the epileptic hippocampus of fully kindled and pilocarpine-treated adult rats exhibiting TLE. In vitro, huNSPCs not only produced all three central nervous system neural cell types, but also differentiated into ganglionic eminences-derived γ-aminobutyric acid (GABA)-ergic interneurons and released GABA in response to the depolarization induced by a high K+ medium. NSPC grafting reduced behavioral seizure duration, afterdischarge duration on electroencephalograms, and seizure stage in the kindling model, as well as the frequency and the duration of spontaneous recurrent motor seizures in pilocarpine-induced animals. However, NSPC grafting neither improved spatial learning or memory function in pilocarpine-treated animals. Following transplantation, grafted cells showed extensive migration around the injection site, robust engraftment, and long-term survival, along with differentiation into β-tubulin III+ neurons (∼34%), APC-CC1+ oligodendrocytes (∼28%), and GFAP+ astrocytes (∼8%). Furthermore, among donor-derived cells, ∼24% produced GABA. Additionally, to explain the effect of seizure suppression after NSPC grafting, we examined the anticonvulsant glial cell-derived neurotrophic factor (GDNF) levels in host hippocampal astrocytes and mossy fiber sprouting into the supragranular layer of the dentate gyrus in the epileptic brain. Grafted cells restored the expression of GDNF in host astrocytes but did not reverse the mossy fiber sprouting, eliminating the latter as potential mechanism. These results suggest that human fetal

  5. Human fetal brain-derived neural stem/progenitor cells grafted into the adult epileptic brain restrain seizures in rat models of temporal lobe epilepsy.

    Directory of Open Access Journals (Sweden)

    Haejin Lee

    Full Text Available Cell transplantation has been suggested as an alternative therapy for temporal lobe epilepsy (TLE because this can suppress spontaneous recurrent seizures in animal models. To evaluate the therapeutic potential of human neural stem/progenitor cells (huNSPCs for treating TLE, we transplanted huNSPCs, derived from an aborted fetal telencephalon at 13 weeks of gestation and expanded in culture as neurospheres over a long time period, into the epileptic hippocampus of fully kindled and pilocarpine-treated adult rats exhibiting TLE. In vitro, huNSPCs not only produced all three central nervous system neural cell types, but also differentiated into ganglionic eminences-derived γ-aminobutyric acid (GABA-ergic interneurons and released GABA in response to the depolarization induced by a high K+ medium. NSPC grafting reduced behavioral seizure duration, afterdischarge duration on electroencephalograms, and seizure stage in the kindling model, as well as the frequency and the duration of spontaneous recurrent motor seizures in pilocarpine-induced animals. However, NSPC grafting neither improved spatial learning or memory function in pilocarpine-treated animals. Following transplantation, grafted cells showed extensive migration around the injection site, robust engraftment, and long-term survival, along with differentiation into β-tubulin III+ neurons (∼34%, APC-CC1+ oligodendrocytes (∼28%, and GFAP+ astrocytes (∼8%. Furthermore, among donor-derived cells, ∼24% produced GABA. Additionally, to explain the effect of seizure suppression after NSPC grafting, we examined the anticonvulsant glial cell-derived neurotrophic factor (GDNF levels in host hippocampal astrocytes and mossy fiber sprouting into the supragranular layer of the dentate gyrus in the epileptic brain. Grafted cells restored the expression of GDNF in host astrocytes but did not reverse the mossy fiber sprouting, eliminating the latter as potential mechanism. These results suggest

  6. Temporal prediction errors in visual and auditory cortices.

    Science.gov (United States)

    Lee, Hweeling; Noppeney, Uta

    2014-04-14

    To form a coherent percept of the environment, the brain needs to bind sensory signals emanating from a common source, but to segregate those from different sources [1]. Temporal correlations and synchrony act as prominent cues for multisensory integration [2-4], but the neural mechanisms by which such cues are identified remain unclear. Predictive coding suggests that the brain iteratively optimizes an internal model of its environment by minimizing the errors between its predictions and the sensory inputs [5,6]. This model enables the brain to predict the temporal evolution of natural audiovisual inputs and their statistical (for example, temporal) relationship. A prediction of this theory is that asynchronous audiovisual signals violating the model's predictions induce an error signal that depends on the directionality of the audiovisual asynchrony. As the visual system generates the dominant temporal predictions for visual leading asynchrony, the delayed auditory inputs are expected to generate a prediction error signal in the auditory system (and vice versa for auditory leading asynchrony). Using functional magnetic resonance imaging (fMRI), we measured participants' brain responses to synchronous, visual leading and auditory leading movies of speech, sinewave speech or music. In line with predictive coding, auditory leading asynchrony elicited a prediction error in visual cortices and visual leading asynchrony in auditory cortices. Our results reveal predictive coding as a generic mechanism to temporally bind signals from multiple senses into a coherent percept. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Pushing the P300-based brain-computer interface beyond 100 bpm: extending performance guided constraints into the temporal domain.

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    Townsend, G; Platsko, V

    2016-04-01

    A new presentation paradigm for the P300-based brain-computer interface (BCI) referred to as the 'asynchronous paradigm' (ASP) is introduced and studied. It is based on the principle of performance guided constraints (Townsend et al 2012 Neurosci. Lett. 531 63-8) extended from the spatial domain into the temporal domain. The traditional constraint of flashing targets in predefined constant epochs of time is eliminated and targets flash asynchronously with timing based instead on constraints intended to improve performance. We propose appropriate temporal constraints to derive the ASP and compare its performance to that of the 'checkerboard paradigm' (CBP), which has previously been shown to be superior to the standard 'row/column paradigm' introduced by Farwell and Donchin (1988 Electroencephalogr. Clin. Neurophysiol. 70 510-23). Ten participants were tested in the ASP and CBP conditions both with traditional flashing items and with flashing faces in place of the targets (see Zhang et al 2012 J. Neural Eng. 9 026018; Kaufmann and Kübler 2014 J. Neural Eng. 11 ; Chen et al 2015 J. Neurosci. Methods 239 18-27). Eleven minutes of calibration data were used as input to a stepwise linear discriminant analysis to derive classification coefficients used for online classification. Accuracy was consistently high for both paradigms (87% and 93%) while information transfer rate was 45% higher for the ASP than the CBP. In a free spelling task, one subject spelled a 66 character sentence (from a 72 item matrix) with 100% accuracy in 3 min and 24 s demonstrating a practical throughput of 120 bits per minute (bpm) with a theoretical upper bound of 258 bpm. The subject repeated the task three times in a row without error. This work represents an advance in P300 speller technology and raises the ceiling that was being reached on P300-based BCIs. Most importantly, the research presented here is a novel and effective general strategy for organising timing for flashing items. The ASP

  8. Language development at 2 years is correlated to brain microstructure in the left superior temporal gyrus at term equivalent age: a diffusion tensor imaging study.

    Science.gov (United States)

    Aeby, Alec; De Tiège, Xavier; Creuzil, Marylise; David, Philippe; Balériaux, Danielle; Van Overmeire, Bart; Metens, Thierry; Van Bogaert, Patrick

    2013-09-01

    This study aims at testing the hypothesis that neurodevelopmental abilities at age 2 years are related with local brain microstructure of preterm infants at term equivalent age. Forty-one preterm infants underwent brain MRI with diffusion tensor imaging sequences to measure mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivity (λ// and λ[perpendicular]) at term equivalent age. Neurodevelopment was assessed at 2 years corrected age using the Bayley III scale. A voxel-based analysis approach, statistical parametric mapping (SPM8), was used to correlate changes of the Bayley III scores with the regional distribution of MD, FA, λ// and λ[perpendicular]. We found that language abilities are negatively correlated to MD, λ// and λ[perpendicular] in the left superior temporal gyrus in preterm infants. These findings suggest that higher MD, λ// and λ[perpendicular] values at term-equivalent age in the left superior temporal gyrus are associated with poorer language scores in later childhood. Consequently, it highlights the key role of the left superior temporal gyrus for the development of language abilities in children. Further studies are needed to assess on an individual basis and on the long term the prognostic value of brain DTI at term equivalent age for the development of language. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Temporal entrainment of cognitive functions: musical mnemonics induce brain plasticity and oscillatory synchrony in neural networks underlying memory.

    Science.gov (United States)

    Thaut, Michael H; Peterson, David A; McIntosh, Gerald C

    2005-12-01

    In a series of experiments, we have begun to investigate the effect of music as a mnemonic device on learning and memory and the underlying plasticity of oscillatory neural networks. We used verbal learning and memory tests (standardized word lists, AVLT) in conjunction with electroencephalographic analysis to determine differences between verbal learning in either a spoken or musical (verbal materials as song lyrics) modality. In healthy adults, learning in both the spoken and music condition was associated with significant increases in oscillatory synchrony across all frequency bands. A significant difference between the spoken and music condition emerged in the cortical topography of the learning-related synchronization. When using EEG measures as predictors during learning for subsequent successful memory recall, significantly increased coherence (phase-locked synchronization) within and between oscillatory brain networks emerged for music in alpha and gamma bands. In a similar study with multiple sclerosis patients, superior learning and memory was shown in the music condition when controlled for word order recall, and subjects were instructed to sing back the word lists. Also, the music condition was associated with a significant power increase in the low-alpha band in bilateral frontal networks, indicating increased neuronal synchronization. Musical learning may access compensatory pathways for memory functions during compromised PFC functions associated with learning and recall. Music learning may also confer a neurophysiological advantage through the stronger synchronization of the neuronal cell assemblies underlying verbal learning and memory. Collectively our data provide evidence that melodic-rhythmic templates as temporal structures in music may drive internal rhythm formation in recurrent cortical networks involved in learning and memory.

  10. Alzheimer-associated presenilin 2 gene is dysregulated in rat medial temporal lobe cortex after complete brain ischemia due to cardiac arrest.

    Science.gov (United States)

    Pluta, Ryszard; Kocki, Janusz; Ułamek-Kozioł, Marzena; Bogucka-Kocka, Anna; Gil-Kulik, Paulina; Januszewski, Sławomir; Jabłoński, Mirosław; Petniak, Alicja; Brzozowska, Judyta; Bogucki, Jacek; Furmaga-Jabłońska, Wanda; Czuczwar, Stanisław J

    2016-02-01

    Brain ischemia may be causally related with Alzheimer's disease. Probably, presenilin gene dysregulation may be associated with Alzheimer's disease neuropathology. Consequently, we have examined quantitative changes in both presenilin 1 and 2 genes in the medial temporal lobe cortex following 10-min global brain ischemia in rats. Global brain ischemia was induced by cardiac arrest in female rats that were allowed to survive for 2, 7 and 30 days. The expression of presenilin genes was evaluated in the rat medial temporal lobe cortex with the use of quantitative RT-PCR analysis. Presenilin 1 gene expression tended to be downregulated from days 2 to 7 postischemia but at day 30, there was a reverse tendency. The greatest overexpression of presenilin 2 gene was noted at 2-nd day whilst on day 7, the expression of this gene was only modestly elevated. Eventually, at day 30 expression of presenilin 2 gene was modestly downregulated. Alterations of presenilin 2 gene expression between 2 and 7 days and between 2 and 30 days were statistically significant. Thus, presented changes suggest that the significant dysregulation of presenilin 2 gene may be connected with a response of neuronal cells to transient global brain ischemia due to cardiac arrest. Finally, the ischemia-induced gene dysregulation may play a key role in the late onset of Alzheimer's-type dementia. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  11. Neuronal ceroid lipofuscinosis genes, CLN2, CLN3 and CLN5 are spatially and temporally co-expressed in a developing mouse brain.

    Science.gov (United States)

    Fabritius, A-L; Vesa, J; Minye, H M; Nakano, I; Kornblum, H; Peltonen, L

    2014-12-01

    Neuronal ceroid lipofuscinosis (NCL) diseases consist of a group of genetically inherited neurodegenerative disorders that share common symptoms such as seizures, psychomotor retardation, blindness, and premature death. Although gene defects behind the NCL diseases are well characterized, very little is known how these defects affect normal development of the brain and cause the pathology of the disease. To obtain understanding of the development of the cell types that are mostly affected by defective function of CLN proteins, timing of expression of CLN2, CLN3 and CLN5 genes was investigated in developing mouse brain. The relationship between the expression pattern and the developmental stage of the brain showed that these genes are co-expressed spatially and temporally during brain development. Throughout the development strong expression of the three mRNAs was detected in germinal epithelium and in ventricle regions, hippocampus and cerebellum, all representing regions that are known to be associated with the formation of new neurons. More specifically, RT-PCR studies on developing mouse cortices revealed that the CLN genes were temporally co-expressed in the neural progenitor cells together with known stem cell markers. This suggested that CLN2, CLN3 and CLN5 genes may play an important role in early embryonal neurogenesis. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Altered Resting State Brain Dynamics in Temporal Lobe Epilepsy Can Be Observed in Spectral Power, Functional Connectivity and Graph Theory Metrics

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    Quraan, Maher A.; McCormick, Cornelia; Cohn, Melanie; Valiante, Taufik A.; McAndrews, Mary Pat

    2013-01-01

    Despite a wealth of EEG epilepsy data that accumulated for over half a century, our ability to understand brain dynamics associated with epilepsy remains limited. Using EEG data from 15 controls and 9 left temporal lobe epilepsy (LTLE) patients, in this study we characterize how the dynamics of the healthy brain differ from the “dynamically balanced” state of the brain of epilepsy patients treated with anti-epileptic drugs in the context of resting state. We show that such differences can be observed in band power, synchronization and network measures, as well as deviations from the small world network (SWN) architecture of the healthy brain. The θ (4–7 Hz) and high α (10–13 Hz) bands showed the biggest deviations from healthy controls across various measures. In particular, patients demonstrated significantly higher power and synchronization than controls in the θ band, but lower synchronization and power in the high α band. Furthermore, differences between controls and patients in graph theory metrics revealed deviations from a SWN architecture. In the θ band epilepsy patients showed deviations toward an orderly network, while in the high α band they deviated toward a random network. These findings show that, despite the focal nature of LTLE, the epileptic brain differs in its global network characteristics from the healthy brain. To our knowledge, this is the only study to encompass power, connectivity and graph theory metrics to investigate the reorganization of resting state functional networks in LTLE patients. PMID:23922658

  13. Fractality of sensations and the brain health: the theory linking neurodegenerative disorder with distortion of spatial and temporal scale-invariance and fractal complexity of the visible world

    Science.gov (United States)

    Zueva, Marina V.

    2015-01-01

    The theory that ties normal functioning and pathology of the brain and visual system with the spatial–temporal structure of the visual and other sensory stimuli is described for the first time in the present study. The deficit of fractal complexity of environmental influences can lead to the distortion of fractal complexity in the visual pathways of the brain and abnormalities of development or aging. The use of fractal light stimuli and fractal stimuli of other modalities can help to restore the functions of the brain, particularly in the elderly and in patients with neurodegenerative disorders or amblyopia. Non-linear dynamics of these physiological processes have a strong base of evidence, which is seen in the impaired fractal regulation of rhythmic activity in aged and diseased brains. From birth to old age, we live in a non-linear world, in which objects and processes with the properties of fractality and non-linearity surround us. Against this background, the evolution of man took place and all periods of life unfolded. Works of art created by man may also have fractal properties. The positive influence of music on cognitive functions is well-known. Insufficiency of sensory experience is believed to play a crucial role in the pathogenesis of amblyopia and age-dependent diseases. The brain is very plastic in its early development, and the plasticity decreases throughout life. However, several studies showed the possibility to reactivate the adult’s neuroplasticity in a variety of ways. We propose that a non-linear structure of sensory information on many spatial and temporal scales is crucial to the brain health and fractal regulation of physiological rhythms. Theoretical substantiation of the author’s theory is presented. Possible applications and the future research that can experimentally confirm or refute the theoretical concept are considered. PMID:26236232

  14. Seizure susceptibility and the brain regional sensitivity to oxidative stress in male and female rats in the lithium-pilocarpine model of temporal lobe epilepsy.

    Science.gov (United States)

    Peternel, Sandra; Pilipović, Kristina; Zupan, Gordana

    2009-04-30

    Several studies have shown the existence of sex differences in the sensitivity to various convulsants in animals and to the development of some epilepsy types in humans. The purpose of this study was to investigate whether there are sex differences in seizure susceptibility and sensitivity of different brain regions to oxidative stress in rats with status epilepticus (SE) induced by lithium-pilocarpine administration, that provides a common experimental model of temporal lobe epilepsy (TLE) in humans. Latencies to isolated full limbic seizures or SE onset as well as the number of the animals presenting full limbic seizures, SE or full limbic seizures that progressed to SE were recorded for 2 h after pilocarpine administration. Number of animals which survived 24 h after SE onset was also monitored. Levels of lipid peroxidation as well as the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in the piriform and entorhinal cortices, temporal neocortex, thalamus, and hippocampus in rats of both sexes, at 24 h after SE onset were determined. Results of our study showed that males developed full limbic seizures and SE more rapidly and in greater number than females. Levels of lipid peroxidation in all brain regions examined, the SOD activities in the piriform and entorhinal cortices, and temporal neocortex as well as the GSH-Px activities in the piriform and entorhinal cortices, and thalamus were significantly higher in rats with SE in comparison to the values of mentioned biochemical parameters in rats of the control groups. Lipid peroxidation level in the temporal neocortex as well as the GSH-Px activity in the hippocampus in male rats were significantly higher in comparison to the values registered in females. With the exception of the thalamus, where SOD activity in male rats with SE was significantly higher in relation to the respective control group and also to females with SE, sex differences in the response of other brain regions

  15. Mapping Circular Current for a Single Brain Cancer Cell’s Spatial-Temporal Orientations Based on a Memristor/Memcapacitor

    Directory of Open Access Journals (Sweden)

    E. T. CHEN

    2014-12-01

    Full Text Available An increasing demand for improving neuronal imaging technologies in spatial- temporal resolution has emphasized in literature. Here we report a nanostructured memrisor/memcapacitor device is able to bio-communicate with the brain cancer cells without using tracers, antibodies and reagent. A “normal neuron” with a biomimetic acetylcholinesterase (ACHE active gorge was made by cross-linked multiple polymers on gold surface as Sensor 1 and an “abnormal neuron” without a hydrophobic ACHE lining as Sensor 2. A cyclic voltammetry (CV method was used. Three types of maps were constructed in light images, contour maps and in 3D dynamic interaction between cross-point location, direct-electron transfer and frequency. The spatial-temporal orientations of the dynamic interaction maps with and without cancer between 10-300 Hz were presented and compared in details regarding how the cancer broken the direct electron-relay circular current, how it changed the brain circuitry structure and its direction. Our results show Sensor 2 without a hydrophobic lining suffered more damage by the cancer than Sensor 1. The cancer’s behaviors toward the neuronal sensors were defined in spatial-temporal fine resolution/orientation in a single cancer concentration and the direction of the synapse network signaling pathway and the trajectory of cancer interaction were identified and mapped.

  16. Image quality improvement in three-dimensional time-of-flight magnetic resonance angiography using the subtraction method for brain and temporal bone diseases.

    Science.gov (United States)

    Peng, Shu-Hui; Shen, Chao-Yu; Wu, Ming-Chi; Lin, Yue-Der; Huang, Chun-Huang; Kang, Ruei-Jin; Tyan, Yeu-Sheng; Tsao, Teng-Fu

    2013-08-01

    Time-of-flight (TOF) magnetic resonance (MR) angiography is based on flow-related enhancement using the T1-weighted spoiled gradient echo, or the fast low-angle shot gradient echo sequence. However, materials with short T1 relaxation times may show hyperintensity signals and contaminate the TOF images. The objective of our study was to determine whether subtraction three-dimensional (3D) TOF MR angiography improves image quality in brain and temporal bone diseases with unwanted contaminations with short T1 relaxation times. During the 12-month study period, patients who had masses with short T1 relaxation times noted on precontrast T1-weighted brain MR images and 24 healthy volunteers were scanned using conventional and subtraction 3D TOF MR angiography. The qualitative evaluation of each MR angiogram was based on signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and scores in three categories, namely, (1) presence of misregistration artifacts, (2) ability to display arterial anatomy selectively (without contamination by materials with short T1 relaxation times), and (3) arterial flow-related enhancement. We included 12 patients with intracranial hematomas, brain tumors, or middle-ear cholesterol granulomas. Subtraction 3D TOF MR angiography yielded higher CNRs between the area of the basilar artery (BA) and normal-appearing parenchyma of the brain and lower SNRs in the area of the BA compared with the conventional technique (147.7 ± 77.6 vs. 130.6 ± 54.2, p angiography did not deteriorate image quality with misregistration artifacts and showed a better selective display of arteries (p angiography is more appropriate than the conventional method in improving the image quality in brain and temporal bone diseases with unwanted contaminations with short T1 relaxation times. Copyright © 2013. Published by Elsevier B.V.

  17. Temporal Changes in Cortical and Hippocampal Expression of Genes Important for Brain Glucose Metabolism Following Controlled Cortical Impact Injury in Mice

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    June Zhou

    2017-09-01

    Full Text Available Traumatic brain injury (TBI causes transient increases and subsequent decreases in brain glucose utilization. The underlying molecular pathways are orchestrated processes and poorly understood. In the current study, we determined temporal changes in cortical and hippocampal expression of genes important for brain glucose/lactate metabolism and the effect of a known neuroprotective drug telmisartan on the expression of these genes after experimental TBI. Adult male C57BL/6J mice (n = 6/group underwent sham or unilateral controlled cortical impact (CCI injury. Their ipsilateral and contralateral cortex and hippocampus were collected 6 h, 1, 3, 7, 14, 21, and 28 days after injury. Expressions of several genes important for brain glucose utilization were determined by qRT-PCR. In results, (1 mRNA levels of three key enzymes in glucose metabolism [hexo kinase (HK 1, pyruvate kinase, and pyruvate dehydrogenase (PDH] were all increased 6 h after injury in the contralateral cortex, followed by decreases at subsequent times in the ipsilateral cortex and hippocampus; (2 capillary glucose transporter Glut-1 mRNA increased, while neuronal glucose transporter Glut-3 mRNA decreased, at various times in the ipsilateral cortex and hippocampus; (3 astrocyte lactate transporter MCT-1 mRNA increased, whereas neuronal lactate transporter MCT-2 mRNA decreased in the ipsilateral cortex and hippocampus; (4 HK2 (an isoform of hexokinase expression increased at all time points in the ipsilateral cortex and hippocampus. GPR81 (lactate receptor mRNA increased at various time points in the ipsilateral cortex and hippocampus. These temporal alterations in gene expression corresponded closely to the patterns of impaired brain glucose utilization reported in both TBI patients and experimental TBI rodents. The observed changes in hippocampal gene expression were delayed and prolonged, when compared with those in the cortex. The patterns of alterations were specific

  18. The neural code of thoughts and feelings. Comment on "Topodynamics of metastable brains" by Arturo Tozzi et al.

    Science.gov (United States)

    Jaušovec, Norbert

    2017-07-01

    Recently the number of theories trying to explain the brain - cognition - behavior relation has been increased. Promoted on the one hand by the development of sophisticated brain imaging techniques, such as functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), and on the other, by complex computational models based on chaos and graph theory. But has this really advanced our understanding of the brain-behavior relation beyond Descartes's dualistic mind body division? One could critically argue that replacing the pineal body with extracellular electric fields represented in the electroencephalogram (EEG) as rapid transitional processes (RTS), combined with algebraic topology and dubbed brain topodynamics [1] is just putting lipstick on an outmoded evergreen.

  19. A 24-hour temporal profile of in vivo brain and heart pet imaging reveals a nocturnal peak in brain 18F-fluorodeoxyglucose uptake.

    Directory of Open Access Journals (Sweden)

    Daan R van der Veen

    Full Text Available Using positron emission tomography, we measured in vivo uptake of (18F-fluorodeoxyglucose (FDG in the brain and heart of C57Bl/6 mice at intervals across a 24-hour light-dark cycle. Our data describe a significant, high amplitude rhythm in FDG uptake throughout the whole brain, peaking at the mid-dark phase of the light-dark cycle, which is the active phase for nocturnal mice. Under these conditions, heart FDG uptake did not vary with time of day, but did show biological variation throughout the 24-hour period for measurements within the same mice. FDG uptake was scanned at different times of day within an individual mouse, and also compared to different times of day between individuals, showing both biological and technical reproducibility of the 24-hour pattern in FDG uptake. Regional analysis of brain FDG uptake revealed especially high amplitude rhythms in the olfactory bulb and cortex, while low amplitude rhythms were observed in the amygdala, brain stem and hypothalamus. Low amplitude 24-hour rhythms in regional FDG uptake may be due to multiple rhythms with different phases in a single brain structure, quenching some of the amplitude. Our data show that the whole brain exhibits significant, high amplitude daily variation in glucose uptake in living mice. Reports applying the 2-deoxy-D[(14C]-glucose method for the quantitative determination of the rates of local cerebral glucose utilization indicate only a small number of brain regions exhibiting a day versus night variation in glucose utilization. In contrast, our data show 24-hour patterns in glucose uptake in most of the brain regions examined, including several regions that do not show a difference in glucose utilization. Our data also emphasizes a methodological requirement of controlling for the time of day of scanning FDG uptake in the brain in both clinical and pre-clinical settings, and suggests waveform normalization of FDG measurements at different times of the day.

  20. Reading, listening and memory-related brain activity in children with early-stage temporal lobe epilepsy of unknown cause-an fMRI study.

    Science.gov (United States)

    Mankinen, Katariina; Ipatti, Pieta; Harila, Marika; Nikkinen, Juha; Paakki, Jyri-Johan; Rytky, Seppo; Starck, Tuomo; Remes, Jukka; Tokariev, Maksym; Carlson, Synnöve; Tervonen, Osmo; Rantala, Heikki; Kiviniemi, Vesa

    2015-09-01

    The changes in functional brain organization associated with paediatric epilepsy are largely unknown. Since children with epilepsy are at risk of developing learning difficulties even before or shortly after the onset of epilepsy, we assessed the functional organization of memory and language in paediatric patients with temporal lobe epilepsy (TLE) at an early stage in epilepsy. Functional magnetic resonance imaging was used to measure the blood oxygenation level-dependent (BOLD) response to four cognitive tasks measuring reading, story listening, memory encoding and retrieval in a population-based group of children with TLE of unknown cause (n = 21) and of normal intelligence and a healthy age and gender-matched control group (n = 21). Significant BOLD response differences were found only in one of the four tasks. In the story listening task, significant differences were found in the right hemispheric temporal structures, thalamus and basal ganglia. Both activation and deactivation differed significantly between the groups, activation being increased and deactivation decreased in the TLE group. Furthermore, the patients with abnormal electroencephalograms (EEGs) showed significantly increased activation bilaterally in the temporal structures, basal ganglia and thalamus relative to those with normal EEGs. The patients with normal interictal EEGs had a significantly stronger deactivation than those with abnormal EEGs or the controls, the differences being located outside the temporal structures. Our results suggest that TLE entails a widespread disruption of brain networks. This needs to be taken into consideration when evaluating learning abilities in patients with TLE. The thalamus seems to play an active role in TLE. The changes in deactivation may reflect neuronal inhibition. Copyright © 2015 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  1. An automatic fuzzy-based multi-temporal brain digital subtraction angiography image fusion algorithm using curvelet transform and content selection strategy.

    Science.gov (United States)

    Momeni, Saba; Pourghassem, Hossein

    2014-08-01

    Recently image fusion has prominent role in medical image processing and is useful to diagnose and treat many diseases. Digital subtraction angiography is one of the most applicable imaging to diagnose brain vascular diseases and radiosurgery of brain. This paper proposes an automatic fuzzy-based multi-temporal fusion algorithm for 2-D digital subtraction angiography images. In this algorithm, for blood vessel map extraction, the valuable frames of brain angiography video are automatically determined to form the digital subtraction angiography images based on a novel definition of vessel dispersion generated by injected contrast material. Our proposed fusion scheme contains different fusion methods for high and low frequency contents based on the coefficient characteristic of wrapping second generation of curvelet transform and a novel content selection strategy. Our proposed content selection strategy is defined based on sample correlation of the curvelet transform coefficients. In our proposed fuzzy-based fusion scheme, the selection of curvelet coefficients are optimized by applying weighted averaging and maximum selection rules for the high frequency coefficients. For low frequency coefficients, the maximum selection rule based on local energy criterion is applied to better visual perception. Our proposed fusion algorithm is evaluated on a perfect brain angiography image dataset consisting of one hundred 2-D internal carotid rotational angiography videos. The obtained results demonstrate the effectiveness and efficiency of our proposed fusion algorithm in comparison with common and basic fusion algorithms.

  2. The brain's dress code: How The Dress allows to decode the neuronal pathway of an optical illusion.

    Science.gov (United States)

    Schlaffke, Lara; Golisch, Anne; Haag, Lauren M; Lenz, Melanie; Heba, Stefanie; Lissek, Silke; Schmidt-Wilcke, Tobias; Eysel, Ulf T; Tegenthoff, Martin

    2015-12-01

    Optical illusions have broadened our understanding of the brain's role in visual perception. A modern day optical illusion emerged from a posted photo of a striped dress, which some perceived as white and gold and others as blue and black. Here we show, using functional magnetic resonance imaging (fMRI), that those who perceive The Dress as white/gold have higher activation in response to the image of The Dress in brain regions critically involved in higher cognition (frontal and parietal brain areas). These results are consistent with theories of top-down modulation and present a neural signature associated with the differences in perceiving The Dress as white/gold or blue/black. Furthermore the results support recent psychophysiological data on this phenomenon and provide a fundamental building block to study interindividual differences in visual processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. How L2-Learners' Brains React to Code-Switches: An ERP Study with Russian Learners of German

    Science.gov (United States)

    Ruigendijk, Esther; Hentschel, Gerd; Zeller, Jan Patrick

    2016-01-01

    This Event Related Potentials (ERP) study investigates auditory processing of sentences with so-called code-switches in Russian learners of German. It has often been argued that switching between two languages results in extra processing cost, although it is not completely clear yet what exactly causes these costs. ERP presents a good method to…

  4. Temporal course of cerebrospinal fluid dynamics and amyloid accumulation in the aging rat brain from three to thirty months

    Directory of Open Access Journals (Sweden)

    Chiu Catherine

    2012-01-01

    Full Text Available Abstract Background Amyloid accumulation in the brain parenchyma is a hallmark of Alzheimer's disease (AD and is seen in normal aging. Alterations in cerebrospinal fluid (CSF dynamics are also associated with normal aging and AD. This study analyzed CSF volume, production and turnover rate in relation to amyloid-beta peptide (Aβ accumulation in the aging rat brain. Methods Aging Fischer 344/Brown-Norway hybrid rats at 3, 12, 20, and 30 months were studied. CSF production was measured by ventriculo-cisternal perfusion with blue dextran in artificial CSF; CSF volume by MRI; and CSF turnover rate by dividing the CSF production rate by the volume of the CSF space. Aβ40 and Aβ42 concentrations in the cortex and hippocampus were measured by ELISA. Results There was a significant linear increase in total cranial CSF volume with age: 3-20 months (p p p p -1 to 12 months (11.30 day-1 and then a decrease to 20 months (10.23 day-1 and 30 months (6.62 day-1. Aβ40 and Aβ42 concentrations in brain increased from 3-30 months (p Conclusions In young rats there is no correlation between CSF turnover and Aβ brain concentrations. After 12 months, CSF turnover decreases as brain Aβ continues to accumulate. This decrease in CSF turnover rate may be one of several clearance pathway alterations that influence age-related accumulation of brain amyloid.

  5. Variation of the gene coding for DARPP-32 (PPP1R1B) and brain connectivity during associative emotional learning

    NARCIS (Netherlands)

    Curcic-Blake, Branislava; Swart, Marte; Ter Horst, Gert J.; Langers, Dave R. M.; Kema, Ido P.; Aleman, Andre

    2012-01-01

    Associative emotional learning, which is important for the social emotional functioning of individuals and is often impaired in psychiatric illnesses, is in part mediated by dopamine and glutamate pathways in the brain. The protein DARPP-32 is involved in the regulation of dopaminergic and

  6. Three-dimensional grammar in the brain: Dissociating the neural correlates of natural sign language and manually coded spoken language.

    Science.gov (United States)

    Jednoróg, Katarzyna; Bola, Łukasz; Mostowski, Piotr; Szwed, Marcin; Boguszewski, Paweł M; Marchewka, Artur; Rutkowski, Paweł

    2015-05-01

    In several countries natural sign languages were considered inadequate for education. Instead, new sign-supported systems were created, based on the belief that spoken/written language is grammatically superior. One such system called SJM (system językowo-migowy) preserves the grammatical and lexical structure of spoken Polish and since 1960s has been extensively employed in schools and on TV. Nevertheless, the Deaf community avoids using SJM for everyday communication, its preferred language being PJM (polski język migowy), a natural sign language, structurally and grammatically independent of spoken Polish and featuring classifier constructions (CCs). Here, for the first time, we compare, with fMRI method, the neural bases of natural vs. devised communication systems. Deaf signers were presented with three types of signed sentences (SJM and PJM with/without CCs). Consistent with previous findings, PJM with CCs compared to either SJM or PJM without CCs recruited the parietal lobes. The reverse comparison revealed activation in the anterior temporal lobes, suggesting increased semantic combinatory processes in lexical sign comprehension. Finally, PJM compared with SJM engaged left posterior superior temporal gyrus and anterior temporal lobe, areas crucial for sentence-level speech comprehension. We suggest that activity in these two areas reflects greater processing efficiency for naturally evolved sign language. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Magnetic resonance imaging (MRI) detection of the murine brain response to light: Temporal differentiation and negative functional MRI changes

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Wei [State Univ. of New York, Stony Brook, NY (United States)]|[Brookhaven National Lab., Upton, NY (United States)]|[Laboratory of Neurosciences, Bethesda, MD (United States); Palyka, I. [State Univ. of New York, Stony Brook, NY (United States)]|[Laboratory of Neurosciences, Bethesda, MD (United States); Li, HaiFang [State Univ. of New York, Stony Brook, NY (United States)] [and others

    1996-06-11

    Using a 9.4 T MRI instrument, we have obtained images of the mouse brain response to photic stimulation during a period between deep anesthesia and the early stages of arousal. The large image enhancements we observe (often >30%) are consistent with literature results extrapolated to 9.4 T. However, there are also two unusual aspects to our findings. (i) The visual area of the brain responds only to changes in stimulus intensity, suggesting that we directly detect operations of the M visual system pathway. Such a channel has been observed in mice by invasive electrophysiology, and described in detail for primates. (ii) Along with the typical positive response in the area of the occipital portion of the brain containing the visual cortex; another area displays decreased signal intensity upon stimulation. 41 refs., 4 figs.

  8. Temporal mapping of CEBPA and CEBPB binding during liver regeneration reveals dynamic occupancy and specific regulatory codes for homeostatic and cell cycle gene batteries

    DEFF Research Database (Denmark)

    Jakobsen, Janus Schou; Waage, Johannes; Rapin, Nicolas

    2013-01-01

    Dynamic shifts in transcription factor binding are central to the regulation of biological processes by allowing rapid changes in gene transcription. However, very few genome-wide studies have examined how transcription factor occupancy is coordinated temporally in vivo in higher animals. Here, w......-renewal of differentiated cells. Taken together, our work emphasizes the power of global temporal analyses of transcription factor occupancy to elucidate mechanisms regulating dynamic biological processes in complex higher organisms....... polymerase II binding data, we find three temporal classes of transcription factor binding to be associated with distinct sets of regulated genes involved in the acute phase response, metabolic/homeostatic functions, or cell cycle progression. Moreover, we demonstrate a previously unrecognized early phase...

  9. The Acute Phase Response and Soman-Induced Status Epilepticus: Temporal, Regional and Cellular Changes in Rat Brain Cytokine Concentrations

    Science.gov (United States)

    2010-07-22

    factors such as IL-1is not surprising. Fur- thermore, IL-6 expression begins the synthesis of corti- cotrophin and glucocorticoids [50], initiating an...L, Cassel G: Effects of HI 6, diazepam and atropine on soman-induced IL-1 beta protein in rat brain. Neurotoxicology 2005, 26:173-181. 24. Shih TM

  10. Processing of visual semantic information to concrete words : temporal dynamics and neural mechanisms indicated by event-related brain potentials

    NARCIS (Netherlands)

    van Schie, Hein T.; Wijers, Albertus A.; Mars, Rogier B.; Benjamins, Jeroen S.; Stowe, Laurie A.

    2005-01-01

    Event-related brain potentials were used to study the retrieval of visual semantic information to concrete words, and to investigate possible structural overlap between visual object working memory and concreteness effects in word processing. Subjects performed an object working memory task that

  11. Processing of visual semantic information to concrete words: temporal dynamics and neural mechanisms indicated by event-related brain potentials

    NARCIS (Netherlands)

    Schie, H.T. van; Wijers, A.A.; Mars, R.B.; Benjamins, J.S.; Stowe, L.A.

    2005-01-01

    Event-related brain potentials were used to study the retrieval of visual semantic information to concrete words, and to investigate possible structural overlap between visual object working memory and concreteness effects in word processing. Subjects performed an object working memory task that

  12. Hippocampal Sclerosis of Aging, a Common Alzheimer's Disease 'Mimic': Risk Genotypes are Associated with Brain Atrophy Outside the Temporal Lobe.

    Science.gov (United States)

    Nho, Kwangsik; Saykin, Andrew J; Nelson, Peter T

    2016-01-01

    Hippocampal sclerosis of aging (HS-Aging) is a common brain disease in older adults with a clinical course that is similar to Alzheimer's disease. Four single-nucleotide polymorphisms (SNPs) have previously shown association with HS-Aging. The present study investigated structural brain changes associated with these SNPs using surface-based analysis. Participants from the Alzheimer's Disease Neuroimaging Initiative cohort (ADNI; n = 1,239), with both MRI scans and genotype data, were used to assess the association between brain atrophy and previously identified HS-Aging risk SNPs in the following genes: GRN, TMEM106B, ABCC9, and KCNMB2 (minor allele frequency for each is >30%). A fifth SNP (near the ABCC9 gene) was evaluated in post-hoc analysis. The GRN risk SNP (rs5848_T) was associated with a pattern of atrophy in the dorsomedial frontal lobes bilaterally, remarkable since GRN is a risk factor for frontotemporal dementia. The ABCC9 risk SNP (rs704180_A) was associated with multifocal atrophy whereas a SNP (rs7488080_A) nearby (∼50 kb upstream) ABCC9 was associated with atrophy in the right entorhinal cortex. Neither TMEM106B (rs1990622_T), KCNMB2 (rs9637454_A), nor any of the non-risk alleles were associated with brain atrophy. When all four previously identified HS-Aging risk SNPs were summed into a polygenic risk score, there was a pattern of associated multifocal brain atrophy in a predominately frontal pattern. We conclude that common SNPs previously linked to HS-Aging pathology were associated with a distinct pattern of anterior cortical atrophy. Genetic variation associated with HS-Aging pathology may represent a non-Alzheimer's disease contribution to atrophy outside of the hippocampus in older adults.

  13. Temporal Processing in the Olfactory System: Can We See a Smell?

    Science.gov (United States)

    Gire, David H.; Restrepo, Diego; Sejnowski, Terrence J.; Greer, Charles; De Carlos, Juan A.; Lopez-Mascaraque, Laura

    2013-01-01

    Sensory processing circuits in the visual and olfactory systems receive input from complex, rapidly changing environments. Although patterns of light and plumes of odor create different distributions of activity in the retina and olfactory bulb, both structures use what appears on the surface similar temporal coding strategies to convey information to higher areas in the brain. We compare temporal coding in the early stages of the olfactory and visual systems, highlighting recent progress in understanding the role of time in olfactory coding during active sensing by behaving animals. We also examine studies that address the divergent circuit mechanisms that generate temporal codes in the two systems, and find that they provide physiological information directly related to functional questions raised by neuroanatomical studies of Ramon y Cajal over a century ago. Consideration of differences in neural activity in sensory systems contributes to generating new approaches to understand signal processing. PMID:23664611

  14. A prospective study of cerebral, frontal lobe, and temporal lobe volumes and neuropsychological performance in children with primary brain tumors treated with cranial radiation.

    Science.gov (United States)

    Agbahiwe, Harold; Rashid, Arif; Horska, Alena; Mahone, E Mark; Lin, Doris; McNutt, Todd; Cohen, Kenneth; Redmond, Kristin; Wharam, Moody; Terezakis, Stephanie

    2017-01-01

    Cranial radiation therapy (RT) is an important component in the treatment of pediatric brain tumors. However, it can result in long-term effects on the developing brain. This prospective study assessed the effects of cranial RT on cerebral, frontal lobe, and temporal lobe volumes and their correlation with higher cognitive functioning. Ten pediatric patients with primary brain tumors treated with cranial RT and 14 age- and sex-matched healthy children serving as controls were evaluated. Quantitative magnetic resonance imaging and neuropsychological assessments (language, memory, auditory and visual processing, and vocabulary) were performed at the baseline and 6, 15, and 27 months after RT. The effects of age, the time since RT, and the cerebral RT dose on brain volumes and neuropsychological performance were analyzed with linear mixed effects model analyses. Cerebral volume increased significantly with age in both groups (P = .01); this increase in volume was more pronounced in younger children. Vocabulary performance was found to be significantly associated with a greater cerebral volume (P = .05) and a lower RT dose (P = .003). No relation was observed between the RT dose and the cerebral volume. There was no difference in the corresponding neuropsychological tests between the 2 groups. This prospective study found significant relations among the RT dose, cerebral volumes, and rate of vocabulary development among children receiving RT. The results of this study provide further support for clinical trials aimed at reducing cranial RT doses in the pediatric population. Cancer 2017;161-168. © 2016 American Cancer Society. © 2016 American Cancer Society.

  15. Deciphering the spatio-temporal expression and stress regulation of Fam107B, the paralog of the resilience-promoting protein DRR1 in the mouse brain.

    Science.gov (United States)

    Masana, M; Jukic, M M; Kretzschmar, A; Wagner, K V; Westerholz, S; Schmidt, M V; Rein, T; Brodski, C; Müller, M B

    2015-04-02

    Understanding the molecular mechanisms that promote stress resilience might open up new therapeutic avenues to prevent stress-related disorders. We recently characterized a stress and glucocorticoid-regulated gene, down-regulated in renal cell carcinoma - DRR1 (Fam107A). DRR1 is expressed in the mouse brain; it is up-regulated by stress and glucocorticoids and modulates neuronal actin dynamics. In the adult mouse, DRR1 was shown to facilitate specific behaviors which might be protective against some of the deleterious consequences of stress exposure: in the hippocampal CA3 region, DRR1 improved cognitive performance whereas in the septum, it specifically increased social behavior. Therefore DRR1 was suggested as a candidate protein promoting stress-resilience. Fam107B (family with sequence similarity 107, member B) is the unique paralog of DRR1, and both share high sequence similarities, predicted glucocorticoid response elements, heat-shock induction and tumor suppressor properties. So far, the role of Fam107B in the central nervous system was not studied. The aim of the present investigation, therefore, was to analyze whether Fam107B and DRR1 display comparable mRNA expression patterns in the brain and whether both are modulated by stress and glucocorticoids. Spatio-temporal mapping of Fam107B mRNA expression in the embryonic and adult mouse brain, by means of in situ hybridization, showed that Fam107B was expressed during embryogenesis and in the adulthood, with particularly high and specific expression in the forming telencephalon suggestive of an involvement in corticogenesis. In the adult mouse, expression was restricted to neurogenic niches, like the dentate gyrus. In contrast to DRR1, Fam107B mRNA expression failed to be modulated by glucocorticoids and social stress in the adult mouse. In summary, Fam107B and DRR1 show different spatio-temporal expression patterns in the central nervous system, suggesting at least partially different functional roles in

  16. A preliminary study on the effects of acute ethanol ingestion on default mode network and temporal fractal properties of the brain.

    Science.gov (United States)

    Weber, Alexander M; Soreni, Noam; Noseworthy, Michael D

    2014-08-01

    To study the effect of acute alcohol intoxication on the functional connectivity of the default mode network (DMN) and temporal fractal properties of the healthy adult brain. Eleven healthy male volunteers were asked to drink 0.59 g/kg of ethanol. Resting state blood oxygen level dependent (rsBOLD) MRI scans were obtained before consumption, 60 min post-consumption and 90 min post-consumption. Before each rsBOLD scan, pointed-resolved spectroscopy (PRESS) (1)H-MRS (magnetic resonance spectroscopy) scans were acquired to measure ethanol levels in the right basal ganglia. Significant changes in DMN connectivity were found following alcohol consumption (p alcohol consumption (p alcohol intoxication. The reduced fractal dimension implies a change in function of small-scale neural networks towards less complex signaling.

  17. Upregulation of Haploinsufficient Gene Expression in the Brain by Targeting a Long Non-coding RNA Improves Seizure Phenotype in a Model of Dravet Syndrome

    Directory of Open Access Journals (Sweden)

    J. Hsiao

    2016-07-01

    Full Text Available Dravet syndrome is a devastating genetic brain disorder caused by heterozygous loss-of-function mutation in the voltage-gated sodium channel gene SCN1A. There are currently no treatments, but the upregulation of SCN1A healthy allele represents an appealing therapeutic strategy. In this study we identified a novel, evolutionary conserved mechanism controlling the expression of SCN1A that is mediated by an antisense non-coding RNA (SCN1ANAT. Using oligonucleotide-based compounds (AntagoNATs targeting SCN1ANAT we were able to induce specific upregulation of SCN1A both in vitro and in vivo, in the brain of Dravet knock-in mouse model and a non-human primate. AntagoNAT-mediated upregulation of Scn1a in postnatal Dravet mice led to significant improvements in seizure phenotype and excitability of hippocampal interneurons. These results further elucidate the pathophysiology of Dravet syndrome and outline a possible new approach for the treatment of this and other genetic disorders with similar etiology.

  18. Pharmacological profile of brain-derived neurotrophic factor (BDNF) splice variant translation using a novel drug screening assay: a "quantitative code".

    Science.gov (United States)

    Vaghi, Valentina; Polacchini, Alessio; Baj, Gabriele; Pinheiro, Vera L M; Vicario, Annalisa; Tongiorgi, Enrico

    2014-10-03

    The neurotrophin brain-derived neurotrophic factor (BDNF) is a key regulator of neuronal development and plasticity. BDNF is a major pharmaceutical target in neurodevelopmental and psychiatric disorders. However, pharmacological modulation of this neurotrophin is challenging because BDNF is generated by multiple, alternatively spliced transcripts with different 5'- and 3'UTRs. Each BDNF mRNA variant is transcribed independently, but translation regulation is unknown. To evaluate the translatability of BDNF transcripts, we developed an in vitro luciferase assay in human neuroblastoma cells. In unstimulated cells, each BDNF 5'- and 3'UTR determined a different basal translation level of the luciferase reporter gene. However, constructs with either a 5'UTR or a 3'UTR alone showed poor translation modulation by BDNF, KCl, dihydroxyphenylglycine, AMPA, NMDA, dopamine, acetylcholine, norepinephrine, or serotonin. Constructs consisting of the luciferase reporter gene flanked by the 5'UTR of one of the most abundant BDNF transcripts in the brain (exons 1, 2c, 4, and 6) and the long 3'UTR responded selectively to stimulation with the different receptor agonists, and only transcripts 2c and 6 were increased by the antidepressants desipramine and mirtazapine. We propose that BDNF mRNA variants represent "a quantitative code" for regulated expression of the protein. Thus, to discriminate the efficacy of drugs in stimulating BDNF synthesis, it is appropriate to use variant-specific in vitro screening tests. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Feature-coding transitions to conjunction-coding with progression through human visual cortex.

    Science.gov (United States)

    Cowell, Rosemary A; Leger, Krystal R; Serences, John T

    2017-12-01

    Identifying an object and distinguishing it from similar items depends upon the ability to perceive its component parts as conjoined into a cohesive whole, but the brain mechanisms underlying this ability remain elusive. The ventral visual processing pathway in primates is organized hierarchically: Neuronal responses in early stages are sensitive to the manipulation of simple visual features, whereas neuronal responses in subsequent stages are tuned to increasingly complex stimulus attributes. It is widely assumed that feature-coding dominates in early visual cortex whereas later visual regions employ conjunction-coding in which object representations are different from the sum of their simple feature parts. However, no study in humans has demonstrated that putative object-level codes in higher visual cortex cannot be accounted for by feature-coding and that putative feature codes in regions prior to ventral temporal cortex are not equally well characterized as object-level codes. Thus the existence of a transition from feature- to conjunction-coding in human visual cortex remains unconfirmed, and if a transition does occur its location remains unknown. By employing multivariate analysis of functional imaging data, we measure both feature-coding and conjunction-coding directly, using the same set of visual stimuli, and pit them against each other to reveal the relative dominance of one vs. the other throughout cortex. Our results reveal a transition from feature-coding in early visual cortex to conjunction-coding in both inferior temporal and posterior parietal cortices. This novel method enables the use of experimentally controlled stimulus features to investigate population-level feature and conjunction codes throughout human cortex. NEW & NOTEWORTHY We use a novel analysis of neuroimaging data to assess representations throughout visual cortex, revealing a transition from feature-coding to conjunction-coding along both ventral and dorsal pathways. Occipital

  20. Whole-brain analytic measures of network communication reveal increased structure-function correlation in right temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Jonathan Wirsich

    2016-01-01

    In rTLE patients, we found a widespread hypercorrelated functional network. Network communication analysis revealed greater unspecific branching of the shortest path (search information in the structural connectome and a higher global correlation between the structural and functional connectivity for the patient group. We also found evidence for a preserved structural rich-club in the patient group. In sum, global augmentation of structure-function correlation might be linked to a smaller functional repertoire in rTLE patients, while sparing the central core of the brain which may represent a pathway that facilitates the spread of seizures.

  1. Temporal and morphological differences in post-embryonic differentiation of the mushroom bodies in the brain of workers, queens, and drones of Apis mellifera (Hymenoptera, Apidae).

    Science.gov (United States)

    Roat, Thaisa Cristina; da Cruz Landim, Carminda

    2008-12-01

    The mushroom bodies are structures present in the insect brain described as centers for the neural basis of learning, memory, and other higher functions. Honeybees (Apis mellifera) are insects with a sophisticated system of spatial orientation and possess well-developed learning and memory capabilities, which are associated with neural and brain structures. Thus, the present study aimed to compare the mushroom bodies during post-embryonic development and in newly emerged males, workers, and queens using light and transmission electron microscopy to examine how differential morphological characteristics are established during development. Measurements of structures were also taken in several post-embryonic developmental phases in order to evaluate size differences during the process and in the adult organs. The results show that workers, queens, and males exhibit temporal and size differences during the post-embryonic development of mushroom bodies, probably as adaptations to differences in behavior complexity. The mushroom bodies of workers are precociously formed and are larger than those of queens and drones. Thus, workers have the largest mushroom bodies resulting from differential development during metamorphosis.

  2. [Spatio-Temporal Bioelectrical Brain Activity Organization during Reading Syntagmatic and Paradigmatic Collocations by Students with Different Foreign Language Proficiency].

    Science.gov (United States)

    Sokolova, L V; Cherkasova, A S

    2015-01-01

    Texts or words/pseudowords are often used as stimuli for human verbal activity research. Our study pays attention to decoding processes of grammatical constructions consisted of two-three words--collocations. Russian and English collocation sets without any narrative were presented to Russian-speaking students with different English language skill. Stimulus material had two types of collocations: paradigmatic and syntagmatic. 30 students (average age--20.4 ± 0.22) took part in the study, they were divided into two equal groups depending on their English language skill (linguists/nonlinguists). During reading brain bioelectrical activity of cortex has been registered from 12 electrodes in alfa-, beta-, theta-bands. Coherent function reflecting cooperation of different cortical areas during reading collocations has been analyzed. Increase of interhemispheric and diagonal connections while reading collocations in different languages in the group of students with low knowledge of foreign language testifies of importance of functional cooperation between the hemispheres. It has been found out that brain bioelectrical activity of students with good foreign language knowledge during reading of all collocation types in Russian and English is characterized by economization of nervous substrate resources compared to nonlinguists. Selective activation of certain cortical areas has also been observed (depending on the grammatical construction type) in nonlinguists group that is probably related to special decoding system which processes presented stimuli. Reading Russian paradigmatic constructions by nonlinguists entailed increase between left cortical areas, reading of English syntagmatic collocations--between right ones.

  3. Temporal Genetic Modifications after Controlled Cortical Impact—Understanding Traumatic Brain Injury through a Systematic Network Approach

    Directory of Open Access Journals (Sweden)

    Yung-Hao Wong

    2016-02-01

    Full Text Available Traumatic brain injury (TBI is a primary injury caused by external physical force and also a secondary injury caused by biological processes such as metabolic, cellular, and other molecular events that eventually lead to brain cell death, tissue and nerve damage, and atrophy. It is a common disease process (as opposed to an event that causes disabilities and high death rates. In order to treat all the repercussions of this injury, treatment becomes increasingly complex and difficult throughout the evolution of a TBI. Using high-throughput microarray data, we developed a systems biology approach to explore potential molecular mechanisms at four time points post-TBI (4, 8, 24, and 72 h, using a controlled cortical impact (CCI model. We identified 27, 50, 48, and 59 significant proteins as network biomarkers at these four time points, respectively. We present their network structures to illustrate the protein–protein interactions (PPIs. We also identified UBC (Ubiquitin C, SUMO1, CDKN1A (cyclindependent kinase inhibitor 1A, and MYC as the core network biomarkers at the four time points, respectively. Using the functional analytical tool MetaCore™, we explored regulatory mechanisms and biological processes and conducted a statistical analysis of the four networks. The analytical results support some recent findings regarding TBI and provide additional guidance and directions for future research.

  4. Examining Brain-Cognition Effects of Ginkgo Biloba Extract: Brain Activation in the Left Temporal and Left Prefrontal Cortex in an Object Working Memory Task

    Directory of Open Access Journals (Sweden)

    R. B. Silberstein

    2011-01-01

    Full Text Available Ginkgo Biloba extract (GBE is increasingly used to alleviate symptoms of age related cognitive impairment, with preclinical evidence pointing to a pro-cholinergic effect. While a number of behavioral studies have reported improvements to working memory (WM associated with GBE, electrophysiological studies of GBE have typically been limited to recordings during a resting state. The current study investigated the chronic effects of GBE on steady state visually evoked potential (SSVEP topography in nineteen healthy middle-aged (50-61 year old male participants whilst completing an object WM task. A randomized double-blind crossover design was employed in which participants were allocated to receive 14 days GBE and 14 days placebo in random order. For both groups, SSVEP was recorded from 64 scalp electrode sites during the completion of an object WM task both pre- and 14 days post-treatment. GBE was found to improve behavioural performance on the WM task. GBE was also found to increase the SSVEP amplitude at occipital and frontal sites and increase SSVEP latency at left temporal and left frontal sites during the hold component of the WM task. These SSVEP changes associated with GBE may represent more efficient processing during WM task completion.

  5. Temporal Profile of Microtubule-Associated Protein 2: A Novel Indicator of Diffuse Brain Injury Severity and Early Mortality after Brain Trauma.

    Science.gov (United States)

    Papa, Linda; Robicsek, Steven A; Brophy, Gretchen M; Wang, Kevin K W; Hannay, H Julia; Heaton, Shelley; Schmalfuss, Ilona; Gabrielli, Andrea; Hayes, Ronald L; Robertson, Claudia S

    2018-01-01

    This study compared cerebrospinal fluid (CSF) levels of microtubule-associated protein 2 (MAP-2) from adult patients with severe traumatic brain injury (TBI) with uninjured controls over 10 days, and examined the relationship between MAP-2 concentrations and acute clinical and radiologic measures of injury severity along with mortality at 2 weeks and over 6 months. This prospective study, conducted at two Level 1 trauma centers, enrolled adults with severe TBI (Glasgow Coma Scale [GCS] score ≤8) requiring a ventriculostomy, as well as controls. Ventricular CSF was sampled from each patient at 6, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, and 240 h following TBI and analyzed via enzyme-linked immunosorbent assay for MAP-2 (ng/mL). Injury severity was assessed by the GCS score, Marshall Classification on computed tomography (CT), Rotterdam CT score, and mortality. There were 151 patients enrolled-130 TBI and 21 control patients. MAP-2 was detectable within 6 h of injury and was significantly elevated compared with controls (p < 0.001) at each time-point. MAP-2 was highest within 72 h of injury and decreased gradually over 10 days. The area under the receiver operating characteristic curve for deciphering TBI versus controls at the earliest time-point CSF was obtained was 0.96 (95% CI 0.93-0.99) and for the maximal 24-h level was 0.98 (95% CI 0.97-1.00). The area under the curve for initial MAP-2 levels predicting 2-week mortality was 0.80 at 6 h, 0.81 at 12 h, 0.75 at 18 h, 0.75 at 24 h, and 0.80 at 48 h. Those with Diffuse Injury III-IV had much higher initial (p = 0.033) and maximal (p = 0.003) MAP-2 levels than those with Diffuse Injury I-II. There was a graded increase in the overall levels and peaks of MAP-2 as the degree of diffuse injury increased within the first 120 h post-injury. These data suggest that early levels of MAP-2 reflect severity of diffuse brain injury and predict 2-week mortality in TBI patients. These

  6. Evaluation of epileptogenic focus in temporal lobe: correlation between ictal brain SPECT, magnetic resonance imaging and magnetic resonance spectroscopy; Avaliacao de foco epileptogenico do lobo temporal: correlacao entre SPECT ictal, ressonancia magnetica e ressonancia magnetica com espectroscopia de protons

    Energy Technology Data Exchange (ETDEWEB)

    Diegues, Maria Elena Martins [Hospital Universitario Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil). Servico de Medicina Nuclear]. E-mail: emartyns@terra.com.br; Pellini, Marcos Pinto; Alves-Leon, Soniza Vieira [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina; Domingues, Romeu Cortes [Clinica de Diagnostico por Imagem (CDPI), Rio de Janeiro, RJ (Brazil)

    2004-02-01

    The purpose of this study was to determine the degree of concordance between radiological and radioisotopic methods and, if positive, to evaluate the usefulness of ictal SPECT in the localization of the epileptogenic focus. Ictal brain SPECT, magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) were performed on six patients with refractory temporal lobe epilepsy. Ictal SPECT was performed after withdrawal of the anti-epileptogenic drugs during video-EEG monitoring, using {sup 99m}Tc-ECD, administered to patients at the time of the ictus. MRI was performed in T1, T2 and FLAIR sequences and MRS was obtained using the PRESS technique, with a single voxel positioned in both hippocampi. The statistical analysis included the determination of the values of Kappa (k), standard error (se) and significance level (p) for the lateralization of the ictal focus. The analysis of all findings was based on EEG localization of the ictal discharge, seizure duration (109-280 s; 152 s average) and time of radiotracer injection (30-262 s; 96 s average). We obtained correlated data in four patients (67 per cent) and values of k = 0.67, se = 0.38, and p 0.041. We concluded that there is a concordance between ictal SPECT, MRI and MRS data and the usefulness of the radioisotopic procedure is related to a non diagnostic EEG and when there is a discordant or misleading diagnosis after a comparative analysis of EEG and MRS. (author)

  7. Temporal and spatial trends in prey composition of wahoo Acanthocybium solandri: a diet analysis from the central North Pacific Ocean using visual and DNA bar-coding techniques.

    Science.gov (United States)

    Oyafuso, Z S; Toonen, R J; Franklin, E C

    2016-04-01

    A diet analysis was conducted on 444 wahoo Acanthocybium solandri caught in the central North Pacific Ocean longline fishery and a nearshore troll fishery surrounding the Hawaiian Islands from June to December 2014. In addition to traditional observational methods of stomach contents, a DNA bar-coding approach was integrated into the analysis by sequencing the cytochrome c oxidase subunit 1 (COI) region of the mtDNA genome to taxonomically identify individual prey items that could not be classified visually to species. For nearshore-caught A. solandri, juvenile pre-settlement reef fish species from various families dominated the prey composition during the summer months, followed primarily by Carangidae in autumn months. Gempylidae, Echeneidae and Scombridae were dominant prey taxa from the offshore fishery. Molidae was a common prey family found in stomachs collected north-east of the Hawaiian Archipelago while tetraodontiform reef fishes, known to have extended pelagic stages, were prominent prey items south-west of the Hawaiian Islands. The diet composition of A. solandri was indicative of an adaptive feeder and thus revealed dominant geographic and seasonal abundances of certain taxa from various ecosystems in the marine environment. The addition of molecular bar-coding to the traditional visual method of prey identifications allowed for a more comprehensive range of the prey field of A. solandri to be identified and should be used as a standard component in future diet studies. © 2016 The Fisheries Society of the British Isles.

  8. Importance of angle corection in transcranial color-coded duplex insonation of arteries at the base of the brain

    Directory of Open Access Journals (Sweden)

    Lepić Toplica

    2015-01-01

    Full Text Available Background/Aim. Transcranial color-coded duplex (TCCD sonography allows visualization of the vessels being examined and measurement of the angle of insonation. The published literature suggests that blood vessels are insonated at the angle lower than 30 degrees, hence no correction for the angle is necessary. The aim of this study was to determine the availability of intracranial blood vessels for insonation, and the percentage of arteries and their segments which can be insonated at the angles lower than 30 degrees. Methods. The study included 120 patients (mean age 51. For each of the segments the angle of insonation was registered based on TCCD vizualization, and hemodynamic parameters were measured. The angle of insonation was measured using combined B-mode and color Doppler vizualization, as the angle between the direction of the ultrasound beam and the axis of the shown arterial segment. Results. The total success rate of insonation was 86.33% (1,554 out of 1,800. The mean angle of insonation value in all the examined arterial segments was 42 degrees. The insonation angle was higher than 30 degrees in about three quarters of the examined segments, especially in the A2 segment of the anterior cerebral artery (98%, the P1 segmet of the posterior cerebral artery (87% and in the terminal internal carotid artery (83%. The A1 segment of the anterior cerebral artery showed the best insonation conditions with the angle of insonation lower than 30 degrees in 53% of the cases. Conclusion. The presented results of angles of insonation measurements for the anterior, middle and posterior cerebral arteries and their segments, as well as the terminal portion of the internal carotid artery clearly indicate that their average values in tested segments were very often higher than 30 degrees, which can cause an error in blood flow velocity measurement that cannot be ignored. The results confirm the necessity of correcting flow velocity values on the basis of

  9. The Role of Frontal Cortical and Medial-Temporal Lobe Brain Areas in Learning a Bayesian Prior Belief on Reversals.

    Science.gov (United States)

    Jang, Anthony I; Costa, Vincent D; Rudebeck, Peter H; Chudasama, Yogita; Murray, Elisabeth A; Averbeck, Bruno B

    2015-08-19

    Reversal learning has been extensively studied across species as a task that indexes the ability to flexibly make and reverse deterministic stimulus-reward associations. Although various brain lesions have been found to affect performance on this task, the behavioral processes affected by these lesions have not yet been determined. This task includes at least two kinds of learning. First, subjects have to learn and reverse stimulus-reward associations in each block of trials. Second, subjects become more proficient at reversing choice preferences as they experience more reversals. We have developed a Bayesian approach to separately characterize these two learning processes. Reversal of choice behavior within each block is driven by a combination of evidence that a reversal has occurred, and a prior belief in reversals that evolves with experience across blocks. We applied the approach to behavior obtained from 89 macaques, comprising 12 lesion groups and a control group. We found that animals from all of the groups reversed more quickly as they experienced more reversals, and correspondingly they updated their prior beliefs about reversals at the same rate. However, the initial values of the priors that the various groups of animals brought to the task differed significantly, and it was these initial priors that led to the differences in behavior. Thus, by taking a Bayesian approach we find that variability in reversal-learning performance attributable to different neural systems is primarily driven by different prior beliefs about reversals that each group brings to the task. The ability to use prior knowledge to adapt choice behavior is critical for flexible decision making. Reversal learning is often studied as a form of flexible decision making. However, prior studies have not identified which brain regions are important for the formation and use of prior beliefs to guide choice behavior. Here we develop a Bayesian approach that formally characterizes learning

  10. Comprehensive Identification of Long Non-coding RNAs in Purified Cell Types from the Brain Reveals Functional LncRNA in OPC Fate Determination.

    Directory of Open Access Journals (Sweden)

    Xiaomin Dong

    2015-12-01

    Full Text Available Long non-coding RNAs (lncRNAs (> 200 bp play crucial roles in transcriptional regulation during numerous biological processes. However, it is challenging to comprehensively identify lncRNAs, because they are often expressed at low levels and with more cell-type specificity than are protein-coding genes. In the present study, we performed ab initio transcriptome reconstruction using eight purified cell populations from mouse cortex and detected more than 5000 lncRNAs. Predicting the functions of lncRNAs using cell-type specific data revealed their potential functional roles in Central Nervous System (CNS development. We performed motif searches in ENCODE DNase I digital footprint data and Mouse ENCODE promoters to infer transcription factor (TF occupancy. By integrating TF binding and cell-type specific transcriptomic data, we constructed a novel framework that is useful for systematically identifying lncRNAs that are potentially essential for brain cell fate determination. Based on this integrative analysis, we identified lncRNAs that are regulated during Oligodendrocyte Precursor Cell (OPC differentiation from Neural Stem Cells (NSCs and that are likely to be involved in oligodendrogenesis. The top candidate, lnc-OPC, shows highly specific expression in OPCs and remarkable sequence conservation among placental mammals. Interestingly, lnc-OPC is significantly up-regulated in glial progenitors from experimental autoimmune encephalomyelitis (EAE mouse models compared to wild-type mice. OLIG2-binding sites in the upstream regulatory region of lnc-OPC were identified by ChIP (chromatin immunoprecipitation-Sequencing and validated by luciferase assays. Loss-of-function experiments confirmed that lnc-OPC plays a functional role in OPC genesis. Overall, our results substantiated the role of lncRNA in OPC fate determination and provided an unprecedented data source for future functional investigations in CNS cell types. We present our datasets and

  11. Effect of whole-body exposure to the 848.5 MHz code division multiple access (CDMA) electromagnetic field on adult neurogenesis in the young, healthy rat brain.

    Science.gov (United States)

    Kim, Hye Sun; Kim, Yeon Ju; Lee, Yu Hee; Lee, Yun-Sil; Choi, Hyung Do; Pack, Jeong-Ki; Kim, Nam; Ahn, Young Hwan

    2015-04-01

    Whether exposure to the 848.5 MHz code division multiple access (CDMA) signal affects adult neurogenesis is unclear. An animal experiment was performed with a reverberation chamber designed as a whole-body CDMA exposure system. Male Sprague-Dawley rats were assigned to three groups (n = 6 per group): Cage-control, sham-exposed, and CDMA-exposed groups. Rats in the CDMA-exposed group were exposed to the CDMA signal at a 2 W/kg whole-body specific absorption rate (SAR) for 1 or 8 h daily, 5 days per week, for 2 weeks. Rats received a single intraperitoneal injection of Bromodeoxyuridine (BrdU) to label proliferative cells daily for the last five consecutive days of CDMA signal exposure. An unbiased stereological method was used to estimate the number of BrdU(+) cells in the subventricular zone (SVZ) and dentate gyrus (DG). We found no significant changes in the number of BrdU(+) cells in the SVZ or DG in the CDMA-exposed rats, compared with rats in the cage-control and sham-exposed groups (p > 0.05). Our results suggest that exposure to the CDMA signal does not affect neurogenesis in the adult rat brain, at least under our experimental conditions.

  12. The processing of semantic relatedness in the brain: Evidence from associative and categorical false recognition effects following transcranial direct current stimulation of the left anterior temporal lobe.

    Science.gov (United States)

    Díez, Emiliano; Gómez-Ariza, Carlos J; Díez-Álamo, Antonio M; Alonso, María A; Fernandez, Angel

    2017-08-01

    A dominant view of the role of the anterior temporal lobe (ATL) in semantic memory is that it serves as an integration hub, specialized in the processing of semantic relatedness by way of mechanisms that bind together information from different brain areas to form coherent amodal representations of concepts. Two recent experiments, using brain stimulation techniques along with the Deese-Roediger-McDermott (DRM) paradigm, have found a consistent false memory reduction effect following stimulation of the ATL, pointing to the importance of the ATL in semantic/conceptual processing. To more precisely identify the specific process being involved, we conducted a DRM experiment in which transcranial direct current stimulation (anode/cathode/sham) was applied over the participants' left ATL during the study of lists of words that were associatively related to their non-presented critical words (e.g., rotten, worm, red, tree, liqueur, unripe, cake, food, eden, peel, for the critical item apple) or categorically related (e.g., pear, banana, peach, orange, cantaloupe, watermelon, strawberry, cherry, kiwi, plum, for the same critical item apple). The results showed that correct recognition was not affected by stimulation. However, an interaction between stimulation condition and type of relation for false memories was found, explained by a significant false recognition reduction effect in the anodal condition for associative lists that was not observed for categorical lists. Results are congruent with previous findings and, more importantly, they help to clarify the nature and locus of false memory reduction effects, suggesting a differential role of the left ATL, and providing critical evidence for understanding the creation of semantic relatedness-based memory illusions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Increase in serotonin 5-HT sub 1A receptors in prefrontal and temporal cortices of brains from patients with chronic schizophrenia

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Takeshi; Nishino, Naoki; Nakai, Hisao; Tanaka, Chikako (Kobe Univ. School of Medicine (Japan))

    1991-01-01

    Binding studies with ({sup 3}H)8-hydroxy-2-(di-n-propylamino)tetralin (({sup 3}H)8-OH-DPAT), a specific serotonin{sub 1A} (5-HT{sub 1A}) receptor agonist, were done on the autopsied brains from control subjects and from patients with chronic schizophrenia. In the controls, representative Scatchard plots for the specific ({sup 3}H)8-OH-DPAT bindings in the prefrontal cortex and hippocampus revealed a single component of high affinity binding site. The ({sup 3}H)8-OH-DPAT bindings to the prefrontal cortex and hippocampus were potently inhibited by serotonin and 5-HT{sub 1A} agonists, while other neurotransmitters, 5-HT{sub 2} and 5-HT{sub 3} related compounds did not inhibit the binding. The bindings were decreased in the presence of 0.1mM GTP and 0.1mM GppNHp but not in the presence of 0.1mM GMP. In the prefrontal and temporal cortices of schizophrenics, there was a significant increase in the specific ({sup 3}H)8-OH-DPAT binding, by 40% and 60%, respectively, with no change in the hippocampus, amygdala, cingulum, motor cortex, parietal or occipital cortex, as compared to findings in the controls.

  14. Brain Basics

    Medline Plus

    Full Text Available ... that contains codes to make proteins and other important body chemicals. DNA also includes information to control ... cells required for normal function and plays an important role during early brain development. It may also ...

  15. Temporal Order Processing of Syllables in the Left Parietal Lobe

    National Research Council Canada - National Science Library

    Moser, Dana; Baker, Julie M; Sanchez, Carmen E; Rorden, Chris; Fridriksson, Julius

    2009-01-01

    Speech processing requires the temporal parsing of syllable order. Individuals suffering from posterior left hemisphere brain injury often exhibit temporal processing deficits as well as language deficits...

  16. Implications of within-fiber temporal coding for perceptual studies of F0 discrimination and discrimination of harmonic and inharmonic tone complexes.

    Science.gov (United States)

    Kale, Sushrut; Micheyl, Christophe; Heinz, Michael G

    2014-06-01

    Recent psychophysical studies suggest that normal-hearing (NH) listeners can use acoustic temporal-fine-structure (TFS) cues for accurately discriminating shifts in the fundamental frequency (F0) of complex tones, or equal shifts in all component frequencies, even when the components are peripherally unresolved. The present study quantified both envelope (ENV) and TFS cues in single auditory-nerve (AN) fiber responses (henceforth referred to as neural ENV and TFS cues) from NH chinchillas in response to harmonic and inharmonic complex tones similar to those used in recent psychophysical studies. The lowest component in the tone complex (i.e., harmonic rank N) was systematically varied from 2 to 20 to produce various resolvability conditions in chinchillas (partially resolved to completely unresolved). Neural responses to different pairs of TEST (F0 or frequency shifted) and standard or reference (REF) stimuli were used to compute shuffled cross-correlograms, from which cross-correlation coefficients representing the degree of similarity between responses were derived separately for TFS and ENV. For a given F0 shift, the dissimilarity (TEST vs. REF) was greater for neural TFS than ENV. However, this difference was stimulus-based; the sensitivities of the neural TFS and ENV metrics were equivalent for equal absolute shifts of their relevant frequencies (center component and F0, respectively). For the F0-discrimination task, both ENV and TFS cues were available and could in principle be used for task performance. However, in contrast to human performance, neural TFS cues quantified with our cross-correlation coefficients were unaffected by phase randomization, suggesting that F0 discrimination for unresolved harmonics does not depend solely on TFS cues. For the frequency-shift (harmonic-versus-inharmonic) discrimination task, neural ENV cues were not available. Neural TFS cues were available and could in principle support performance in this task; however, in contrast

  17. Alteration of functional connectivity within visuospatial working memory-related brain network in patients with right temporal lobe epilepsy: a resting-state fMRI study.

    Science.gov (United States)

    Lv, Zong-xia; Huang, Dong-Hong; Ye, Wei; Chen, Zi-rong; Huang, Wen-li; Zheng, Jin-ou

    2014-06-01

    This study aimed to investigate the resting-state brain network related to visuospatial working memory (VSWM) in patients with right temporal lobe epilepsy (rTLE). The functional mechanism underlying the cognitive impairment in VSWM was also determined. Fifteen patients with rTLE and 16 healthy controls matched for age, gender, and handedness underwent a 6-min resting-state functional MRI session and a neuropsychological test using VSWM_Nback. The VSWM-related brain network at rest was extracted using multiple independent component analysis; the spatial distribution and the functional connectivity (FC) parameters of the cerebral network were compared between groups. Behavioral data were subsequently correlated with the mean Z-value in voxels showing significant FC difference during intergroup comparison. The distribution of the VSWM-related resting-state network (RSN) in the group with rTLE was virtually consistent with that in the healthy controls. The distribution involved the dorsolateral prefrontal lobe and parietal lobe in the right hemisphere and the partial inferior parietal lobe and posterior lobe of the cerebellum in the left hemisphere (p<0.05, AlphaSim corrected). Between-group differences suggest that the group with rTLE had a decreased FC within the right superior frontal lobe (BA8), right middle frontal lobe, and right ventromedial prefrontal lobe compared with the controls (p<0.05, AlphaSim corrected). The regions of increased FC in rTLE were localized within the right superior frontal lobe (BA11), right superior parietal lobe, and left posterior lobe of the cerebellum (p<0.05, AlphaSim corrected). Moreover, patients with rTLE performed worse than controls in the VSWM_Nback test, and there were negative correlations between ACCmeanRT (2-back) and the mean Z-value in the voxels showing decreased or increased FC in rTLE (p<0.05). The results suggest that the alteration of the VSWM-related RSN might underpin the VSWM impairment in patients with rTLE and

  18. Assessment of Hyperperfusion by Brain Perfusion SPECT in Transient Neurological Deterioration after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Won; Kim, Yu Kyeong; Lee, Sang Mi; Eo, Jae Sun; Oh, Chang Wan; Lee, Won Woo; Paeng, Jin Chul; Kim, Sang Eun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2008-08-15

    Transient neurological deterioration (TND) is one of the complications after extracranial-intracranial bypass surgery, and it has been assumed to be caused by postoperative transient hyperperfusion. This study was performed to evaluate the relationship between TND and preoperative and postoperative cerebral perfusion status on brain perfusion SPECT following superficial temporal artery.middle cerebral artery (STA-MCA) anastomosis surgery. A total of 60 STA-MCA anastomosis surgeries of 56 patients (mean age: 50{+-}16 yrs; M:F=29:27; atherosclerotic disease: 33, moyamoya disease: 27) which were done between September 2003 and July 2006 were enrolled. The resting cerebral perfusion and cerebral vascular reserve (CVR) after acetazolamide challenge were measured before and 10 days after surgery using 99mTc-ethylcysteinate dimer (ECD) SPECT. Moreover, the cerebral perfusion was measured on the third postoperative day. With the use of the statistical parametric mapping and probabilistic brain atlas, the counts for the middle cerebral artery (MCA) territory were calculated for each image, and statistical analyses were performed. In 6 of 60 cases (10%), TND occurred after surgery. In all patients, the preoperative cerebral perfusion of affected MCA territory was significantly lower than that of contralateral side (p=0.002). The cerebral perfusion on the third and tenth day after surgery was significantly higher than preoperative cerebral perfusion (p=0.001, p=0.02). In TND patients, basal cerebral perfusion and CVR on preoperative SPECT were significantly lower than those of non-TND patients (p=0.01, p=0.05). Further, the increases in cerebral perfusion on the third day after surgery were significant higher than those in other patients (p=0.008). In patients with TND, the cerebral perfusion ratio of affected side to contralateral side on third postoperative day was significantly higher than that of other patients (p=0.002). However, there was no significant difference of

  19. Long-Term Effects of Anterior Thalamic Nucleus Deep Brain Stimulation on Spatial Learning in the Pilocarpine Model of Temporal Lobe Epilepsy.

    Science.gov (United States)

    Ferreira, Elenn Soares; Vieira, Laís Gabrielle; Moraes, Daniela Macedo; Amorim, Beatriz O; Malheiros, Jackeline Moraes; Hamani, Clement; Covolan, Luciene

    2018-02-01

    Cognitive impairment is a significant comorbidity of temporal lobe epilepsy that is associated with extensive hippocampal cell loss. Deep brain stimulation (DBS) of the anterior thalamic nucleus (ANT) has been used for the treatment of refractory partial seizures. In the pilocarpine model of epilepsy, ANT DBS applied during status epilepticus (SE) reduces hippocampal inflammation and apoptosis. When given to chronic epileptic animals it reduces hippocampal excitability and seizure frequency. Here, we tested whether ANT DBS delivered during SE and the silent phase of the pilocarpine model would reduce cognitive impairment when animals became chronically epileptic. SE was induced by a systemic pilocarpine injection (320 mg/kg). Immediately after SE onset, rats were assigned to receive DBS during the first six hours of SE (n = 8; DBSa group) or during SE + the silent period (i.e., 6 h/day until the animals developed the first spontaneous recurrent seizure; n = 10; DBSs group). Four months following SE, animals underwent water maze testing and histological evaluation. Nonstimulated chronic epileptic animals (n = 13; PCTL group) and age-matched naïve rats (n = 11, CTL group) were used as controls. Results were analyzed by repeated-measures analyses of variance (RM_ANOVA) and one-way ANOVAs, followed by Newman-Keuls post hoc tests. Although all groups learned the spatial task, epileptic animals with or without DBS spent significantly less time in the platform quadrant, denoting a spatial memory deficit (p < 0.02). Despite these negative behavioral results, we found that animals given DBS had a significantly higher number of cells in the CA1 region and dentate gyrus. Mossy fiber sprouting was similar among all epileptic groups. Despite lesser hippocampal neuronal loss, ANT DBS delivered either during SE or during SE and the silent phase of the pilocarpine model did not mitigate memory deficits in chronic epileptic rats. © 2017 International

  20. Low complexity hevc intra coding

    OpenAIRE

    Ruiz Coll, José Damián

    2016-01-01

    Over the last few decades, much research has focused on the development and optimization of video codecs for media distribution to end-users via the Internet, broadcasts or mobile networks, but also for videoconferencing and for the recording on optical disks for media distribution. Most of the video coding standards for delivery are characterized by using a high efficiency hybrid schema, based on inter-prediction coding for temporal picture decorrelation, and intra-prediction coding for spat...

  1. Cyclone Codes

    OpenAIRE

    Schindelhauer, Christian; Jakoby, Andreas; Köhler, Sven

    2016-01-01

    We introduce Cyclone codes which are rateless erasure resilient codes. They combine Pair codes with Luby Transform (LT) codes by computing a code symbol from a random set of data symbols using bitwise XOR and cyclic shift operations. The number of data symbols is chosen according to the Robust Soliton distribution. XOR and cyclic shift operations establish a unitary commutative ring if data symbols have a length of $p-1$ bits, for some prime number $p$. We consider the graph given by code sym...

  2. Temporal Codes for Memories: Issues and Problems.

    Science.gov (United States)

    1977-04-01

    Whether all memories that were ever established still persist is a matter for coffee debates; the fact remains that the usual adult possesses an...for specific dates they were quite unable to reconstruct the dates. It has been reported (Gibson & Levin, 197S) that children afflicted with dyslexia ...of an event in the flow of events is relatively poor. In fact , however, there is very little systematic evidence on the matter. This "test" is an

  3. Coding Partitions

    Directory of Open Access Journals (Sweden)

    Fabio Burderi

    2007-05-01

    Full Text Available Motivated by the study of decipherability conditions for codes weaker than Unique Decipherability (UD, we introduce the notion of coding partition. Such a notion generalizes that of UD code and, for codes that are not UD, allows to recover the ``unique decipherability" at the level of the classes of the partition. By tacking into account the natural order between the partitions, we define the characteristic partition of a code X as the finest coding partition of X. This leads to introduce the canonical decomposition of a code in at most one unambiguouscomponent and other (if any totally ambiguouscomponents. In the case the code is finite, we give an algorithm for computing its canonical partition. This, in particular, allows to decide whether a given partition of a finite code X is a coding partition. This last problem is then approached in the case the code is a rational set. We prove its decidability under the hypothesis that the partition contains a finite number of classes and each class is a rational set. Moreover we conjecture that the canonical partition satisfies such a hypothesis. Finally we consider also some relationships between coding partitions and varieties of codes.

  4. The Art of Readable Code

    CERN Document Server

    Boswell, Dustin

    2011-01-01

    As programmers, we've all seen source code that's so ugly and buggy it makes our brain ache. Over the past five years, authors Dustin Boswell and Trevor Foucher have analyzed hundreds of examples of "bad code" (much of it their own) to determine why they're bad and how they could be improved. Their conclusion? You need to write code that minimizes the time it would take someone else to understand it-even if that someone else is you. This book focuses on basic principles and practical techniques you can apply every time you write code. Using easy-to-digest code examples from different languag

  5. Coding Class

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine; Hansbøl, Mikala

    Sammenfatning af de mest væsentlige pointer fra hovedrapporten: Dokumentation og evaluering af Coding Class......Sammenfatning af de mest væsentlige pointer fra hovedrapporten: Dokumentation og evaluering af Coding Class...

  6. Long non-coding RNA nuclear paraspeckle assembly transcript 1 inhibits the apoptosis of retina Müller cells after diabetic retinopathy through regulating miR-497/brain-derived neurotrophic factor axis.

    Science.gov (United States)

    Li, Xiu-Juan

    2018-01-01

    The role of long non-coding RNA in diabetic retinopathy, a serious complication of diabetes mellitus, has attracted increasing attention in recent years. The purpose of this study was to explore whether long non-coding RNA nuclear paraspeckle assembly transcript 1 was involved in the context of diabetic retinopathy and its underlying mechanisms. Our results revealed that nuclear paraspeckle assembly transcript 1 was significantly downregulated in the retina of diabetes mellitus rats. Meanwhile, miR-497 was significantly increased in diabetes mellitus rats' retina and high glucose-treated Müller cells, but brain-derived neurotrophic factor was increased. We also found that high glucose-induced apoptosis of Müller cells was accompanied by the significant downregulation of nuclear paraspeckle assembly transcript 1 in vitro. Further study demonstrated that high glucose-promoted Müller cells apoptosis through downregulating nuclear paraspeckle assembly transcript 1 and downregulated nuclear paraspeckle assembly transcript 1 mediated this effect via negative regulating miR-497. Moreover, brain-derived neurotrophic factor was negatively regulated by miR-497 and associated with the apoptosis of Müller cells under high glucose. Our results suggested that under diabetic conditions, downregulated nuclear paraspeckle assembly transcript 1 decreased the expression of brain-derived neurotrophic factor through elevating miR-497, thereby promoting Müller cells apoptosis and aggravating diabetic retinopathy.

  7. code {poems}

    Directory of Open Access Journals (Sweden)

    Ishac Bertran

    2012-08-01

    Full Text Available "Exploring the potential of code to communicate at the level of poetry," the code­ {poems} project solicited submissions from code­writers in response to the notion of a poem, written in a software language which is semantically valid. These selections reveal the inner workings, constitutive elements, and styles of both a particular software and its authors.

  8. Discrepancy in Expression of β-Secretase and Amyloid-β Protein Precursor in Alzheimer-Related Genes in the Rat Medial Temporal Lobe Cortex Following Transient Global Brain Ischemia.

    Science.gov (United States)

    Pluta, Ryszard; Kocki, Janusz; Ułamek-Kozioł, Marzena; Petniak, Alicja; Gil-Kulik, Paulina; Januszewski, Sławomir; Bogucki, Jacek; Jabłoński, Mirosław; Brzozowska, Judyta; Furmaga-Jabłońska, Wanda; Bogucka-Kocka, Anna; Czuczwar, Stanisław J

    2016-01-01

    Brain ischemia may be causally related with Alzheimer's disease. Presumably, β-secretase and amyloid-β protein precursor gene expression changes may be associated with Alzheimer's disease neuropathology. Consequently, we have examined quantitative changes in both β-secretase and amyloid-β protein precursor genes in the medial temporal lobe cortex with the use of quantitative rtPCR analysis following 10-min global brain ischemia in rats with survival of 2, 7, and 30 days. The greatest significant overexpression of β-secretase gene was noted on the 2nd day, while on days 7-30 the expression of this gene was only modestly downregulated. Amyloid-β protein precursor gene was downregulated on the 2nd day, but on days 7-30 postischemia, there was a significant reverse tendency. Thus, the demonstrated alterations indicate that the considerable changes of expression of β-secretase and amyloid-β protein precursor genes may be connected with a response of neurons in medial temporal lobe cortex to transient global brain ischemia. Finally, the ischemia-induced gene changes may play a key role in a late and slow onset of Alzheimer-type pathology.

  9. Multiplexed coding in the human basal ganglia

    Science.gov (United States)

    Andres, D. S.; Cerquetti, D.; Merello, M.

    2016-04-01

    A classic controversy in neuroscience is whether information carried by spike trains is encoded by a time averaged measure (e.g. a rate code), or by complex time patterns (i.e. a time code). Here we apply a tool to quantitatively analyze the neural code. We make use of an algorithm based on the calculation of the temporal structure function, which permits to distinguish what scales of a signal are dominated by a complex temporal organization or a randomly generated process. In terms of the neural code, this kind of analysis makes it possible to detect temporal scales at which a time patterns coding scheme or alternatively a rate code are present. Additionally, finding the temporal scale at which the correlation between interspike intervals fades, the length of the basic information unit of the code can be established, and hence the word length of the code can be found. We apply this algorithm to neuronal recordings obtained from the Globus Pallidus pars interna from a human patient with Parkinson’s disease, and show that a time pattern coding and a rate coding scheme co-exist at different temporal scales, offering a new example of multiplexed neuronal coding.

  10. Neural underpinnings of music: the polyrhythmic brain.

    Science.gov (United States)

    Vuust, Peter; Gebauer, Line K; Witek, Maria A G

    2014-01-01

    Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has the remarkable ability to move our minds and bodies. Why do certain rhythms make us want to tap our feet, bop our heads or even get up and dance? And how does the brain process rhythmically complex rhythms during our experiences of music? In this chapter, we describe some common forms of rhythmic complexity in music and propose that the theory of predictive coding can explain how rhythm and rhythmic complexity are processed in the brain. We also consider how this theory may reveal why we feel so compelled by rhythmic tension in music. First, musical-theoretical and neuroscientific frameworks of rhythm are presented, in which rhythm perception is conceptualized as an interaction between what is heard ('rhythm') and the brain's anticipatory structuring of music ('the meter'). Second, three different examples of tension between rhythm and meter in music are described: syncopation, polyrhythm and groove. Third, we present the theory of predictive coding of music, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain's Bayesian minimization of the error between the input to the brain and the brain's prior expectations. Fourth, empirical studies of neural and behavioral effects of syncopation, polyrhythm and groove will be reported, and we propose how these studies can be seen as special cases of the predictive coding theory. Finally, we argue that musical rhythm exploits the brain's general principles of anticipation and propose that pleasure from musical rhythm may be a result of such anticipatory mechanisms.

  11. Temporal predictive mechanisms modulate motor reaction time during initiation and inhibition of speech and hand movement.

    Science.gov (United States)

    Johari, Karim; Behroozmand, Roozbeh

    2017-08-01

    Skilled movement is mediated by motor commands executed with extremely fine temporal precision. The question of how the brain incorporates temporal information to perform motor actions has remained unanswered. This study investigated the effect of stimulus temporal predictability on response timing of speech and hand movement. Subjects performed a randomized vowel vocalization or button press task in two counterbalanced blocks in response to temporally-predictable and unpredictable visual cues. Results indicated that speech and hand reaction time was decreased for predictable compared with unpredictable stimuli. This finding suggests that a temporal predictive code is established to capture temporal dynamics of sensory cues in order to produce faster movements in responses to predictable stimuli. In addition, results revealed a main effect of modality, indicating faster hand movement compared with speech. We suggest that this effect is accounted for by the inherent complexity of speech production compared with hand movement. Lastly, we found that movement inhibition was faster than initiation for both hand and speech, suggesting that movement initiation requires a longer processing time to coordinate activities across multiple regions in the brain. These findings provide new insights into the mechanisms of temporal information processing during initiation and inhibition of speech and hand movement. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Neocortical Temporal Lobe Epilepsy

    Science.gov (United States)

    Bercovici, Eduard; Kumar, Balagobal Santosh; Mirsattari, Seyed M.

    2012-01-01

    Complex partial seizures (CPSs) can present with various semiologies, while mesial temporal lobe epilepsy (mTLE) is a well-recognized cause of CPS, neocortical temporal lobe epilepsy (nTLE) albeit being less common is increasingly recognized as separate disease entity. Differentiating the two remains a challenge for epileptologists as many symptoms overlap due to reciprocal connections between the neocortical and the mesial temporal regions. Various studies have attempted to correctly localize the seizure focus in nTLE as patients with this disorder may benefit from surgery. While earlier work predicted poor outcomes in this population, recent work challenges those ideas yielding good outcomes in part due to better localization using improved anatomical and functional techniques. This paper provides a comprehensive review of the diagnostic workup, particularly the application of recent advances in electroencephalography and functional brain imaging, in neocortical temporal lobe epilepsy. PMID:22953057

  13. Identification of brain regions predicting epileptogenesis by serial [18F]GE-180 positron emission tomography imaging of neuroinflammation in a rat model of temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Vera Russmann

    2017-01-01

    In conclusion, the data provide evidence that [18F]GE-180 PET brain imaging can serve as a biomarker of epileptogenesis. The identification of brain regions with predictive value might facilitate the development of preventive concepts as well as the early assessment of the interventional success. Future studies are necessary to further confirm the predictivity of the approach.

  14. Reversal of age-related increase in brain protein oxidation, decrease in enzyme activity, and loss in temporal and spatial memory by chronic administration of the spin-trapping compound N-tert-butyl-alpha-phenylnitrone

    Energy Technology Data Exchange (ETDEWEB)

    Carney, J.M.; Starke-Reed, P.E.; Oliver, C.N.; Landum, R.W.; Cheng, M.S.; Wu, J.F.; Floyd, R.A. (Univ. of Kentucky, Lexington (USA))

    1991-05-01

    Oxygen free radicals and oxidative events have been implicated as playing a role in bringing about the changes in cellular function that occur during aging. Brain readily undergoes oxidative damage, so it is important to determine if aging-induced changes in brain may be associated with oxidative events. Previously we demonstrated that brain damage caused by an ischemia/reperfusion insult involved oxidative events. In addition, pretreatment with the spin-trapping compound N-tert-butyl-alpha-phenylnitrone (PBN) diminished the increase in oxidized protein and the loss of glutamine synthetase (GS) activity that accompanied ischemia/reperfusion injury in brain. We report here that aged gerbils had a significantly higher level of oxidized protein as assessed by carbonyl residues and decreased GS and neutral protease activities as compared to young adult gerbils. We also found that chronic treatment with the spin-trapping compound PBN caused a decrease in the level of oxidized protein and an increase in both GS and neutral protease activity in aged Mongolian gerbil brain. In contrast to aged gerbils, PBN treatment of young adult gerbils had no significant effect on brain oxidized protein content or GS activity. Male gerbils, young adults (3 months of age) and retired breeders (15-18 months of age), were treated with PBN for 14 days with twice daily dosages of 32 mg/kg. If PBN administration was ceased after 2 weeks, the significantly decreased level of oxidized protein and increased GS and neutral protease activities in old gerbils changed in a monotonic fashion back to the levels observed in aged gerbils prior to PBN administration. We also report that old gerbils make more errors than young animals and that older gerbils treated with PBN made fewer errors in a radial arm maze test for temporal and spatial memory than the untreated aged controls.

  15. Sharing code.

    Science.gov (United States)

    Kubilius, Jonas

    2014-01-01

    Sharing code is becoming increasingly important in the wake of Open Science. In this review I describe and compare two popular code-sharing utilities, GitHub and Open Science Framework (OSF). GitHub is a mature, industry-standard tool but lacks focus towards researchers. In comparison, OSF offers a one-stop solution for researchers but a lot of functionality is still under development. I conclude by listing alternative lesser-known tools for code and materials sharing.

  16. Analog Coding.

    Science.gov (United States)

    CODING, ANALOG SYSTEMS), INFORMATION THEORY, DATA TRANSMISSION SYSTEMS , TRANSMITTER RECEIVERS, WHITE NOISE, PROBABILITY, ERRORS, PROBABILITY DENSITY FUNCTIONS, DIFFERENTIAL EQUATIONS, SET THEORY, COMPUTER PROGRAMS

  17. Divergence coding for convolutional codes

    Directory of Open Access Journals (Sweden)

    Valery Zolotarev

    2017-01-01

    Full Text Available In the paper we propose a new coding/decoding on the divergence principle. A new divergent multithreshold decoder (MTD for convolutional self-orthogonal codes contains two threshold elements. The second threshold element decodes the code with the code distance one greater than for the first threshold element. Errorcorrecting possibility of the new MTD modification have been higher than traditional MTD. Simulation results show that the performance of the divergent schemes allow to approach area of its effective work to channel capacity approximately on 0,5 dB. Note that we include the enough effective Viterbi decoder instead of the first threshold element, the divergence principle can reach more. Index Terms — error-correcting coding, convolutional code, decoder, multithreshold decoder, Viterbi algorithm.

  18. Speaking Code

    DEFF Research Database (Denmark)

    Cox, Geoff

    Speaking Code begins by invoking the “Hello World” convention used by programmers when learning a new language, helping to establish the interplay of text and code that runs through the book. Interweaving the voice of critical writing from the humanities with the tradition of computing and software...... development, Speaking Code unfolds an argument to undermine the distinctions between criticism and practice, and to emphasize the aesthetic and political aspects of software studies. Not reducible to its functional aspects, program code mirrors the instability inherent in the relationship of speech......; alternatives to mainstream development, from performances of the live-coding scene to the organizational forms of commons-based peer production; the democratic promise of social media and their paradoxical role in suppressing political expression; and the market’s emptying out of possibilities for free...

  19. Understanding perception through neural "codes".

    Science.gov (United States)

    Freeman, Walter J

    2011-07-01

    A major challenge for cognitive scientists is to deduce and explain the neural mechanisms of the rapid transposition between stimulus energy and recalled memory-between the specific (sensation) and the generic (perception)-in both material and mental aspects. Researchers are attempting three explanations in terms of neural codes. The microscopic code: cellular neurobiologists correlate stimulus properties with the rates and frequencies of trains of action potentials induced by stimuli and carried by topologically organized axons. The mesoscopic code: cognitive scientists formulate symbolic codes in trains of action potentials from feature-detector neurons of phonemes, lines, odorants, vibrations, faces, etc., that object-detector neurons bind into representations of stimuli. The macroscopic code: neurodynamicists extract neural correlates of stimuli and associated behaviors in spatial patterns of oscillatory fields of dendritic activity, which self-organize and evolve on trajectories through high-dimensional brain state space. This multivariate code is expressed in landscapes of chaotic attractors. Unlike other scientific codes, such as DNA and the periodic table, these neural codes have no alphabet or syntax. They are epistemological metaphors that experimentalists need to measure neural activity and engineers need to model brain functions. My aim is to describe the main properties of the macroscopic code and the grand challenge it poses: how do very large patterns of textured synchronized oscillations form in cortex so quickly? © 2010 IEEE

  20. Brain Basics: Know Your Brain

    Science.gov (United States)

    ... frontal lobes. Whether you appreciate symphonies or rock music, your brain responds through the activity of these lobes. At the top of each temporal lobe is an area responsible for receiving ... those associated with music. Other parts of this lobe seem to integrate ...

  1. Semantic category-based decoding of human brain activity using a Gabor-based model by estimating intracranial field potential range in temporal cortex.

    Science.gov (United States)

    Jahromy, Fateme Zareayan; Daliri, Mohammed Reza

    2017-01-01

    Predicting and decoding the recorded neural activity for visual stimuli is the topic of many studies. This prediction can be made by comparing the model's responses to different stimuli with the available recorded brain signal. The neural activities can be decoded then by finding the stimulus which has generated the nearest model's response to the recorded signal. In this study, a model is proposed which can estimate the response of human brain to images from different conceptual categories by inserting the visual stimuli as the model input after filtering by Gabor wavelets. This helped us to find each image's low level visual features. Afterward, the extracted image features were applied to the input of a curve fitting neural network. As the output, the range of intracranial field potential was estimated. This was performed separately for each pixel of the image. To evaluate the model's accuracy, two factors were used, namely the Pearson correlation and Normalized root mean square error. The results show that the proposed model can accurately estimate the brain's response to conceptual categories To decode the brain' activity based on the observed semantic category in each test observations by using of the model, we calculated the distance between the recorded signal and the model responses to all stimuli from different categories and assigned the category of the nearest model response to brain's response in that trial. To this end, a K-nearest neighbors classifier based on Euclidean distance was used. This leaded to a classification accuracy which was significantly higher than chance level. So, the proposed model can be used to decode the activity of the brain in response to the visual stimuli.

  2. Coding Labour

    Directory of Open Access Journals (Sweden)

    Anthony McCosker

    2014-03-01

    Full Text Available As well as introducing the Coding Labour section, the authors explore the diffusion of code across the material contexts of everyday life, through the objects and tools of mediation, the systems and practices of cultural production and organisational management, and in the material conditions of labour. Taking code beyond computation and software, their specific focus is on the increasingly familiar connections between code and labour with a focus on the codification and modulation of affect through technologies and practices of management within the contemporary work organisation. In the grey literature of spreadsheets, minutes, workload models, email and the like they identify a violence of forms through which workplace affect, in its constant flux of crisis and ‘prodromal’ modes, is regulated and governed.

  3. Coding labour

    National Research Council Canada - National Science Library

    McCosker, Anthony; Milne, Esther

    2014-01-01

    ... software. Code encompasses the laws that regulate human affairs and the operation of capital, behavioural mores and accepted ways of acting, but it also defines the building blocks of life as DNA...

  4. The microbiota and the gut-brain axis : insights from the temporal and spatial mucosal alterations during colonisation of the germfree mouse intestine

    NARCIS (Netherlands)

    El Aidy, S; Kunze, W; Bienenstock, J; Kleerebezem, M

    2012-01-01

    The influence of the gut microbiota on the nervous system, brain development and behaviour, in particular during microbial colonisation of the host, has recently been receiving profound interest. Our time-resolved mining of combined data analyses of the ex-germfree mouse intestine during a 30-day

  5. Hippocampal Sclerosis of Aging, a Common Alzheimer’s Disease ‘Mimic’: Risk Genotypes are Associated with Brain Atrophy Outside the Temporal Lobe

    Science.gov (United States)

    Nho, Kwangsik; Saykin, Andrew J.; Nelson, Peter T.

    2016-01-01

    Hippocampal sclerosis of aging (HS-Aging) is a common brain disease in older adults with a clinical course that is similar to Alzheimer’s disease. Four single-nucleotide polymorphisms (SNPs) have previously shown association with HS-Aging. The present study investigated structural brain changes associated with these SNPs using surface-based analysis. Participants from the Alzheimer’s Disease Neuroimaging Initiative cohort (ADNI; n = 1,239), with both MRI scans and genotype data, were used to assess the association between brain atrophy and previously identified HS-Aging risk SNPs in the following genes: GRN, TMEM106B, ABCC9, and KCNMB2 (minor allele frequency for each is >30%). A fifth SNP (near the ABCC9 gene) was evaluated in post-hoc analysis. The GRN risk SNP (rs5848_T) was associated with a pattern of atrophy in the dorsomedial frontal lobes bilaterally, remarkable since GRN is a risk factor for frontotemporal dementia. The ABCC9 risk SNP (rs704180_A) was associated with multifocal atrophy whereas a SNP (rs7488080_A) nearby (~50 kb upstream) ABCC9 was associated with atrophy in the right entorhinal cortex. Neither TMEM106B (rs1990622_T), KCNMB2 (rs9637454_A), nor any of the non-risk alleles were associated with brain atrophy. When all four previously identified HS-Aging risk SNPs were summed into a polygenic risk score, there was a pattern of associated multifocal brain atrophy in a predominately frontal pattern. We conclude that common SNPs previously linked to HS-Aging pathology were associated with a distinct pattern of anterior cortical atrophy. Genetic variation associated with HS-Aging pathology may represent a non-Alzheimer’s disease contribution to atrophy outside of the hippocampus in older adults. PMID:27003218

  6. Olfactory cortical neurons read out a relative time code in the olfactory bulb.

    Science.gov (United States)

    Haddad, Rafi; Lanjuin, Anne; Madisen, Linda; Zeng, Hongkui; Murthy, Venkatesh N; Uchida, Naoshige

    2013-07-01

    Odor stimulation evokes complex spatiotemporal activity in the olfactory bulb, suggesting that both the identity of activated neurons and the timing of their activity convey information about odors. However, whether and how downstream neurons decipher these temporal patterns remains unknown. We addressed this question by measuring the spiking activity of downstream neurons while optogenetically stimulating two foci in the olfactory bulb with varying relative timing in mice. We found that the overall spike rates of piriform cortex neurons (PCNs) were sensitive to the relative timing of activation. Posterior PCNs showed higher sensitivity to relative input times than neurons in the anterior piriform cortex. In contrast, olfactory bulb neurons rarely showed such sensitivity. Thus, the brain can transform a relative time code in the periphery into a firing rate-based representation in central brain areas, providing evidence for the relevance of a relative time-based code in the olfactory bulb.

  7. Analysis of Memory Codes and Cumulative Rehearsal in Observational Learning

    Science.gov (United States)

    Bandura, Albert; And Others

    1974-01-01

    The present study examined the influence of memory codes varying in meaningfulness and retrievability and cumulative rehearsal on retention of observationally learned responses over increasing temporal intervals. (Editor)

  8. Auditory evoked fields elicited by spectral, temporal, and spectral-temporal changes in human cerebral cortex

    Directory of Open Access Journals (Sweden)

    Hidehiko eOkamoto

    2012-05-01

    Full Text Available Natural sounds contain complex spectral components, which are temporally modulated as time-varying signals. Recent studies have suggested that the auditory system encodes spectral and temporal sound information differently. However, it remains unresolved how the human brain processes sounds containing both spectral and temporal changes. In the present study, we investigated human auditory evoked responses elicited by spectral, temporal, and spectral-temporal sound changes by means of magnetoencephalography (MEG. The auditory evoked responses elicited by the spectral-temporal change were very similar to those elicited by the spectral change, but those elicited by the temporal change were delayed by 30 – 50 ms and differed from the others in morphology. The results suggest that human brain responses corresponding to spectral sound changes precede those corresponding to temporal sound changes, even when the spectral and temporal changes occur simultaneously.

  9. New Methods to Study Gustatory Coding.

    Science.gov (United States)

    Boronat-García, Alejandra; Reiter, Sam; Sun, Kui; Stopfer, Mark

    2017-06-29

    The sense of taste allows animals to detect chemicals in the environment, giving rise to behaviors critical for survival. When Gustatory Receptor Neurons (GRNs) detect tastant molecules, they encode information about the identity and concentration of the tastant as patterns of electrical activity that then propagate to follower neurons in the brain. These patterns constitute internal representations of the tastant, which then allow the animal to select actions and form memories. The use of relatively simple animal models has been a powerful tool to study basic principles in sensory coding. Here, we propose three new methods to study gustatory coding using the moth Manduca sexta. First, we present a dissection procedure for exposing the maxillary nerves and the subesophageal zone (SEZ), allowing recording of the activity of GRNs from their axons. Second, we describe the use of extracellular electrodes to record the activity of multiple GRNs by placing tetrode wires directly into the maxillary nerve. Third, we present a new system for delivering and monitoring, with high temporal precision, pulses of different tastants. These methods allow the characterization of neuronal responses in vivo directly from GRNs before, during and after tastants are delivered. We provide examples of voltage traces recorded from multiple GRNs, and present an example of how a spike sorting technique can be applied to the data to identify the responses of individual neurons. Finally, to validate our recording approach, we compare extracellular recordings obtained from GRNs with tetrodes to intracellular recordings obtained with sharp glass electrodes.

  10. Speech coding

    Energy Technology Data Exchange (ETDEWEB)

    Ravishankar, C., Hughes Network Systems, Germantown, MD

    1998-05-08

    Speech is the predominant means of communication between human beings and since the invention of the telephone by Alexander Graham Bell in 1876, speech services have remained to be the core service in almost all telecommunication systems. Original analog methods of telephony had the disadvantage of speech signal getting corrupted by noise, cross-talk and distortion Long haul transmissions which use repeaters to compensate for the loss in signal strength on transmission links also increase the associated noise and distortion. On the other hand digital transmission is relatively immune to noise, cross-talk and distortion primarily because of the capability to faithfully regenerate digital signal at each repeater purely based on a binary decision. Hence end-to-end performance of the digital link essentially becomes independent of the length and operating frequency bands of the link Hence from a transmission point of view digital transmission has been the preferred approach due to its higher immunity to noise. The need to carry digital speech became extremely important from a service provision point of view as well. Modem requirements have introduced the need for robust, flexible and secure services that can carry a multitude of signal types (such as voice, data and video) without a fundamental change in infrastructure. Such a requirement could not have been easily met without the advent of digital transmission systems, thereby requiring speech to be coded digitally. The term Speech Coding is often referred to techniques that represent or code speech signals either directly as a waveform or as a set of parameters by analyzing the speech signal. In either case, the codes are transmitted to the distant end where speech is reconstructed or synthesized using the received set of codes. A more generic term that is applicable to these techniques that is often interchangeably used with speech coding is the term voice coding. This term is more generic in the sense that the

  11. Project Temporalities

    DEFF Research Database (Denmark)

    Tryggestad, Kjell; Justesen, Lise; Mouritsen, Jan

    2013-01-01

    Purpose – The purpose of this paper is to explore how animals can become stakeholders in interaction with project management technologies and what happens with project temporalities when new and surprising stakeholders become part of a project and a recognized matter of concern to be taken...... into account. Design/methodology/approach – The paper is based on a qualitative case study of a project in the building industry. The authors use actor-network theory (ANT) to analyze the emergence of animal stakeholders, stakes and temporalities. Findings – The study shows how project temporalities can...... multiply in interaction with project management technologies and how conventional linear conceptions of project time may be contested with the emergence of new non-human stakeholders and temporalities. Research limitations/implications – The study draws on ANT to show how animals can become stakeholders...

  12. The Aster code; Code Aster

    Energy Technology Data Exchange (ETDEWEB)

    Delbecq, J.M

    1999-07-01

    The Aster code is a 2D or 3D finite-element calculation code for structures developed by the R and D direction of Electricite de France (EdF). This dossier presents a complete overview of the characteristics and uses of the Aster code: introduction of version 4; the context of Aster (organisation of the code development, versions, systems and interfaces, development tools, quality assurance, independent validation); static mechanics (linear thermo-elasticity, Euler buckling, cables, Zarka-Casier method); non-linear mechanics (materials behaviour, big deformations, specific loads, unloading and loss of load proportionality indicators, global algorithm, contact and friction); rupture mechanics (G energy restitution level, restitution level in thermo-elasto-plasticity, 3D local energy restitution level, KI and KII stress intensity factors, calculation of limit loads for structures), specific treatments (fatigue, rupture, wear, error estimation); meshes and models (mesh generation, modeling, loads and boundary conditions, links between different modeling processes, resolution of linear systems, display of results etc..); vibration mechanics (modal and harmonic analysis, dynamics with shocks, direct transient dynamics, seismic analysis and aleatory dynamics, non-linear dynamics, dynamical sub-structuring); fluid-structure interactions (internal acoustics, mass, rigidity and damping); linear and non-linear thermal analysis; steels and metal industry (structure transformations); coupled problems (internal chaining, internal thermo-hydro-mechanical coupling, chaining with other codes); products and services. (J.S.)

  13. Multiband multislice GE-EPI at 7 tesla, with 16-fold acceleration using partial parallel imaging with application to high spatial and temporal whole-brain fMRI.

    Science.gov (United States)

    Moeller, Steen; Yacoub, Essa; Olman, Cheryl A; Auerbach, Edward; Strupp, John; Harel, Noam; Uğurbil, Kâmil

    2010-05-01

    Parallel imaging in the form of multiband radiofrequency excitation, together with reduced k-space coverage in the phase-encode direction, was applied to human gradient echo functional MRI at 7 T for increased volumetric coverage and concurrent high spatial and temporal resolution. Echo planar imaging with simultaneous acquisition of four coronal slices separated by 44mm and simultaneous 4-fold phase-encoding undersampling, resulting in 16-fold acceleration and up to 16-fold maximal aliasing, was investigated. Task/stimulus-induced signal changes and temporal signal behavior under basal conditions were comparable for multiband and standard single-band excitation and longer pulse repetition times. Robust, whole-brain functional mapping at 7 T, with 2 x 2 x 2mm(3) (pulse repetition time 1.25 sec) and 1 x 1 x 2mm(3) (pulse repetition time 1.5 sec) resolutions, covering fields of view of 256 x 256 x 176 mm(3) and 192 x 172 x 176 mm(3), respectively, was demonstrated with current gradient performance. (c) 2010 Wiley-Liss, Inc.

  14. Temporal Prediction Errors Affect Short-Term Memory Scanning Response Time.

    Science.gov (United States)

    Limongi, Roberto; Silva, Angélica M

    2016-11-01

    The Sternberg short-term memory scanning task has been used to unveil cognitive operations involved in time perception. Participants produce time intervals during the task, and the researcher explores how task performance affects interval production - where time estimation error is the dependent variable of interest. The perspective of predictive behavior regards time estimation error as a temporal prediction error (PE), an independent variable that controls cognition, behavior, and learning. Based on this perspective, we investigated whether temporal PEs affect short-term memory scanning. Participants performed temporal predictions while they maintained information in memory. Model inference revealed that PEs affected memory scanning response time independently of the memory-set size effect. We discuss the results within the context of formal and mechanistic models of short-term memory scanning and predictive coding, a Bayes-based theory of brain function. We state the hypothesis that our finding could be associated with weak frontostriatal connections and weak striatal activity.

  15. Network Coding

    Indian Academy of Sciences (India)

    Network coding is a technique to increase the amount of information °ow in a network by mak- ing the key observation that information °ow is fundamentally different from commodity °ow. Whereas, under traditional methods of opera- tion of data networks, intermediate nodes are restricted to simply forwarding their incoming.

  16. Coding Class

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine; Hansbøl, Mikala

    Denne rapport rummer evaluering og dokumentation af Coding Class projektet1. Coding Class projektet blev igangsat i skoleåret 2016/2017 af IT-Branchen i samarbejde med en række medlemsvirksomheder, Københavns kommune, Vejle Kommune, Styrelsen for IT- og Læring (STIL) og den frivillige forening...... Coding Pirates2. Rapporten er forfattet af Docent i digitale læringsressourcer og forskningskoordinator for forsknings- og udviklingsmiljøet Digitalisering i Skolen (DiS), Mikala Hansbøl, fra Institut for Skole og Læring ved Professionshøjskolen Metropol; og Lektor i læringsteknologi, interaktionsdesign......, design tænkning og design-pædagogik, Stine Ejsing-Duun fra Forskningslab: It og Læringsdesign (ILD-LAB) ved Institut for kommunikation og psykologi, Aalborg Universitet i København. Vi har fulgt og gennemført evaluering og dokumentation af Coding Class projektet i perioden november 2016 til maj 2017...

  17. Network Coding

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 7. Network Coding. K V Rashmi Nihar B Shah P Vijay Kumar. General Article Volume 15 Issue 7 July 2010 pp 604-621. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/015/07/0604-0621. Keywords.

  18. Expander Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Expander Codes - The Sipser–Spielman Construction. Priti Shankar. General Article Volume 10 ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science Bangalore 560 012, India.

  19. Temporal order processing of syllables in the left parietal lobe.

    Science.gov (United States)

    Moser, Dana; Baker, Julie M; Sanchez, Carmen E; Rorden, Chris; Fridriksson, Julius

    2009-10-07

    Speech processing requires the temporal parsing of syllable order. Individuals suffering from posterior left hemisphere brain injury often exhibit temporal processing deficits as well as language deficits. Although the right posterior inferior parietal lobe has been implicated in temporal order judgments (TOJs) of visual information, there is limited evidence to support the role of the left inferior parietal lobe (IPL) in processing syllable order. The purpose of this study was to examine whether the left inferior parietal lobe is recruited during temporal order judgments of speech stimuli. Functional magnetic resonance imaging data were collected on 14 normal participants while they completed the following forced-choice tasks: (1) syllable order of multisyllabic pseudowords, (2) syllable identification of single syllables, and (3) gender identification of both multisyllabic and monosyllabic speech stimuli. Results revealed increased neural recruitment in the left inferior parietal lobe when participants made judgments about syllable order compared with both syllable identification and gender identification. These findings suggest that the left inferior parietal lobe plays an important role in processing syllable order and support the hypothesized role of this region as an interface between auditory speech and the articulatory code. Furthermore, a breakdown in this interface may explain some components of the speech deficits observed after posterior damage to the left hemisphere.

  20. Spatial resolution enhancement residual coding using hybrid ...

    Indian Academy of Sciences (India)

    the increasing demands of video communication that motivates researchers to develop cutting- edge algorithms. All the video coding standards, to date, make use of various ... quantization and entropy coding to minimize spatio- temporal, intra-frame, visual, and statistical redundancies, respectively. Intra and inter prediction.

  1. Secreted and Transmembrane αKlotho Isoforms Have Different Spatio-Temporal Profiles in the Brain during Aging and Alzheimer's Disease Progression

    Science.gov (United States)

    Massó, Anna; Sánchez, Angela; Gimenez-Llort, Lydia; Lizcano, Jose Miguel; Cañete, Manuel; García, Belen; Torres-Lista, Virginia; Puig, Meritxell; Bosch, Assumpció; Chillon, Miguel

    2015-01-01

    The Klotho protein is a β-glucuronidase, and its overexpression is associated with life extension. Its mechanism of action is not fully understood, although it has been recently reported that αKlotho improves synaptic and cognitive functions, and it may also influence a variety of structures and functions during CNS maturation and aging. The αKlotho gene has two transcripts, one encoding a transmembrane isoform (m-KL), and the other a putative secreted isoform (s-KL). Unfortunately, little is known about the secreted αKlotho isoform, since available antibodies cannot discriminate s-KL from the KL1 domain cleaved from the transmembrane isoform. This study shows, for the first time, that the klotho transcript produced by alternative splicing generates a stable protein (70 kDa), and that in contrast to the transmembrane Klotho isoform, it is ten times more abundant in the brain than in the kidney suggesting that the two isoforms may have different functions. We also studied whether klotho expression in the CNS was influenced by aging, Alzheimer's disease (AD), or a healthy lifestyle, such as voluntary moderate continuous exercise. We observed a strong correlation between high expression levels of the two klotho transcripts and the healthy status of the animals. Expression of Klotho in brain areas decayed more rapidly in the 3xTg-AD model of AD than in healthy animals, whilst moderate continuous exercise in adulthood prevents the decline in expression of both klotho transcripts. PMID:26599613

  2. Secreted and Transmembrane αKlotho Isoforms Have Different Spatio-Temporal Profiles in the Brain during Aging and Alzheimer's Disease Progression.

    Directory of Open Access Journals (Sweden)

    Anna Massó

    Full Text Available The Klotho protein is a β-glucuronidase, and its overexpression is associated with life extension. Its mechanism of action is not fully understood, although it has been recently reported that αKlotho improves synaptic and cognitive functions, and it may also influence a variety of structures and functions during CNS maturation and aging. The αKlotho gene has two transcripts, one encoding a transmembrane isoform (m-KL, and the other a putative secreted isoform (s-KL. Unfortunately, little is known about the secreted αKlotho isoform, since available antibodies cannot discriminate s-KL from the KL1 domain cleaved from the transmembrane isoform. This study shows, for the first time, that the klotho transcript produced by alternative splicing generates a stable protein (70 kDa, and that in contrast to the transmembrane Klotho isoform, it is ten times more abundant in the brain than in the kidney suggesting that the two isoforms may have different functions. We also studied whether klotho expression in the CNS was influenced by aging, Alzheimer's disease (AD, or a healthy lifestyle, such as voluntary moderate continuous exercise. We observed a strong correlation between high expression levels of the two klotho transcripts and the healthy status of the animals. Expression of Klotho in brain areas decayed more rapidly in the 3xTg-AD model of AD than in healthy animals, whilst moderate continuous exercise in adulthood prevents the decline in expression of both klotho transcripts.

  3. [Disorders in memorizing sentences and texts in local brain lesions].

    Science.gov (United States)

    Mikadze, Iu V

    1983-01-01

    Disturbances of memory for sentences and texts in patients with local brain damages are investigated. The peculiarities of reproducing the superficial (lexic) and deep (sense) structures of the sentences and texts are analyzed. On the basis of the analysis of errors in the reproduction of the "scheme" of the texts the peculiarities of the memory defects specific for the various localization of the brain damage were revealed. It is shown that in damages of the temporal and parietal divisions of the left hemisphere it is the superficial structure, while in damages of the frontal divisions of the same hemisphere it is the deep structure the reproduction of which is affected to the greatest degree. A comparison with the reproduction of both structures in patients with damages of the temporal and parietal divisions of the right hemisphere is presented. The results are discussed from the viewpoint of multi-channel coding of information being stored.

  4. Does the human brain have unique genetically determined networks coding logical and ethical principles and aesthetics? From Plato to novel mirror networks.

    Science.gov (United States)

    Agnati, Luigi Francesco; Agnati, Achille; Mora, Francisco; Fuxe, Kjell

    2007-08-01

    Starting from the assumption that philosophers carry out "experiments" not on concrete objects, but on concepts and relationships between concepts, it could be postulated that the philosopher's way to proceed is not basically different from that followed by scientists. From this similarity of approaches it can be considered that some philosophical problems and theories have a high impact on how to address scientific investigations. One of these issues is certainly the philosophical debate over innate ideas, which is central to the conflict between rationalist and empiricist epistemologies. We started our reflections on the possible presence of innate ideas in the human brain from the observation that there exists strong experimental support for the view that not only complex behaviours (e.g., sexual courtship, parental care) but also aesthetic and ethic judgements can be, at least in part, genetically determined. On these grounds it is suggested that neurobiological findings can give important contributions to the philosophical debate on innatism by putting forward possible explanatory models and heuristic hypotheses.

  5. Rhythmic complexity and predictive coding: a novel approach to modeling rhythm and meter perception in music.

    Science.gov (United States)

    Vuust, Peter; Witek, Maria A G

    2014-01-01

    Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding (PC) as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of PC, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain's Bayesian minimization of the error between the input to the brain and the brain's prior expectations. Third, we develop a PC model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard ("rhythm") and the brain's anticipatory structuring of music ("meter"). Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the PC theory. We argue that musical rhythm exploits the brain's general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms.

  6. Polar Codes

    Science.gov (United States)

    2014-12-01

    added by the decoder is K/ρ+Td. By the last assumption, Td and Te are both ≤ K/ρ, so the total latency added is between 2K/ρ and 4K /ρ. For example...better resolution near the decision point. Reference [12] showed that in decoding a (1024, 512) polar code, using 6-bit LLRs resulted in per- formance

  7. Temporal expression of brain-derived neurotrophic factor (BDNF) mRNA in the rat hippocampus after treatment with selective and mixed monoaminergic antidepressants

    DEFF Research Database (Denmark)

    Larsen, Marianne Hald; Hay-Schmidt, Anders; Rønn, Lars Christian B

    2008-01-01

    Strong evidence suggests that antidepressants work by induction of neuroplastic changes mediated through regulation of brain-derived neurotrophic factor (BDNF). This study was undertaken to investigate the time-course of the effect of three antidepressants; fluoxetine, imipramine and venlafaxine......, which differentially affect monoamine reuptake, on BDNF mRNA expression in the hippocampus. The consequences of increased BDNF in the hippocampus are still indefinite. Here, we also determined the effects on the expression of two other genes (synaptophysin and growth-associated protein-43 (GAP-43......)) known to be involved in synapse formation and axonal growth and likely regulated by BDNF. The effects were determined in rats after sub-chronic (7 days) and chronic (14 and 21 days) treatment using semi-quantitative in situ hybridisation. BDNF mRNA levels in the dentate gyrus (DG) were increased after...

  8. Temporal variation in brain transcriptome is associated with the expression of female mimicry as a sequential male alternative reproductive tactic in fish.

    Science.gov (United States)

    Cardoso, Sara D; Gonçalves, David; Goesmann, Alexander; Canário, Adelino V M; Oliveira, Rui F

    2017-11-07

    Distinct patterns of gene expression often underlie intra- and inter-sexual differences, and the study of this set of co-regulated genes is essential to understand the emergence of complex behavioural phenotypes. Here, we describe the development of a de novo transcriptome and brain gene expression profiles of wild-caught peacock blenny, Salaria pavo, an intertidal fish with sex-role reversal in courtship behaviour (i.e. females are the courting sex) and sequential alternative reproductive tactics in males (i.e. larger and older nest-holder males and smaller and younger sneaker males occur). Sneakers mimic both female's courtship behaviour and nuptial colouration to get access to nests and sneak fertilizations, and later in life transition into nest-holder males. Thus, this species offers the unique opportunity to study how the regulation of gene expression can contribute to intersex phenotypes and to the sequential expression of male and female behavioural phenotypes by the same individual. We found that at the whole brain level, expression of the sneaker tactic was paralleled by broader and divergent gene expression when compared to either females or nest-holder males, which were more similar between themselves. When looking at sex-biased transcripts, sneaker males are intersex rather than being either nest-holder or female-like, and their transcriptome is simultaneously demasculinized for nest-holder-biased transcripts and feminized for female-biased transcripts. These results indicate that evolutionary changes in reproductive plasticity can be achieved through regulation of gene expression, and in particular by varying the magnitude of expression of sex-biased genes, throughout the lifetime of the same individual. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Temporal Processing Dysfunction in Schizophrenia

    Science.gov (United States)

    Carroll, Christine A.; Boggs, Jennifer; O'Donnell, Brian F.; Shekhar, Anantha; Hetrick, William P.

    2008-01-01

    Schizophrenia may be associated with a fundamental disturbance in the temporal coordination of information processing in the brain, leading to classic symptoms of schizophrenia such as thought disorder and disorganized and contextually inappropriate behavior. Despite the growing interest and centrality of time-dependent conceptualizations of the…

  10. Convolutional-Code-Specific CRC Code Design

    OpenAIRE

    Lou, Chung-Yu; Daneshrad, Babak; Wesel, Richard D.

    2015-01-01

    Cyclic redundancy check (CRC) codes check if a codeword is correctly received. This paper presents an algorithm to design CRC codes that are optimized for the code-specific error behavior of a specified feedforward convolutional code. The algorithm utilizes two distinct approaches to computing undetected error probability of a CRC code used with a specific convolutional code. The first approach enumerates the error patterns of the convolutional code and tests if each of them is detectable. Th...

  11. Stereopsis after anterior temporal lobectomy.

    Science.gov (United States)

    Verhoef, Bram-Ernst; Decramer, Thomas; van Loon, Johannes; Goffin, Jan; Van Paesschen, Wim; Janssen, Peter; Theys, Tom

    2016-09-01

    Brain areas critical for stereopsis have been investigated in non-human primates but are largely unknown in the human brain. Microelectrode recordings and functional MRI (fMRI) studies in monkeys have shown that in monkeys the inferior temporal cortex is critically involved in 3D shape categorization. Furthermore, some human fMRI studies similarly suggest an involvement of visual areas in the temporal lobe in depth perception. We aimed to investigate the role of the human anterior temporal neocortex in stereopsis by assessing stereoscopic depth perception before and after anterior temporal lobectomy. Eighteen epilepsy surgery patients were tested, pre- and postoperatively, in 3 different depth discrimination tasks. Sensitivity for local and global disparity was tested in a near-far discrimination task and sensitivity for 3D curvature was assessed in a convex-concave discrimination task, where 3D shapes were presented at different positions in depth. We found no evidence that temporal lobe epilepsy surgery has a significant effect on stereopsis. In contrast with earlier findings, we conclude that local as well as global stereopsis is maintained after unilateral resection of the temporal pole in epilepsy surgery patients. Our findings, together with previous studies, suggest that in humans more posterior visual regions underlie depth perception. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. From concatenated codes to graph codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Høholdt, Tom

    2004-01-01

    We consider codes based on simple bipartite expander graphs. These codes may be seen as the first step leading from product type concatenated codes to more complex graph codes. We emphasize constructions of specific codes of realistic lengths, and study the details of decoding by message passing...

  13. Concatenated codes with convolutional inner codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Thommesen, Christian; Zyablov, Viktor

    1988-01-01

    The minimum distance of concatenated codes with Reed-Solomon outer codes and convolutional inner codes is studied. For suitable combinations of parameters the minimum distance can be lower-bounded by the product of the minimum distances of the inner and outer codes. For a randomized ensemble...... of concatenated codes a lower bound of the Gilbert-Varshamov type is proved...

  14. The inflammatory molecules IL-1β and HMGB1 can rapidly enhance focal seizure generation in a brain slice model of temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Angela eChiavegato

    2014-06-01

    Full Text Available Epilepsy is a neurological disorder characterized by a hyperexcitable brain tissue and unpredictable seizures, i.e., aberrant firing discharges in large neuronal populations. It is well established that proinflammatory cytokines, in addition to their canonical involvement in the immune response, have a crucial role in the mechanism of seizure generation. The purpose of the present study was to investigate the role of interleukin-1β (IL-1β and high mobility group B1 (HMGB1 in the generation of seizure-like discharges using two models of focal epilepsy in a rat entorhinal cortex slice preparation. Seizure like-discharges were evoked by either slice perfusion with low Mg2+ and picrotoxin or with a double NMDA local stimulation in the presence of the proconvulsant 4-amino-pyridine. The effects of IL-1β or HMGB1 were evaluated by monitoring seizure discharge generation through laser scanning microscope imaging of Ca2+ signals from neurons and astrocytes. In the picrotoxin model, we revealed that both cytokines increased the mean frequency of spontaneous ictal-like discharges, whereas only IL-1β reduced the latency and prolonged the duration of the first ictal-like event. In the second model, a single NMDA pulse, per se ineffective, became successful when it was performed after IL-β or HMGB1 local applications. These findings demonstrate that both IL-1β and HMGB1 can rapidly lower focal ictal event threshold and strengthen the possibility that targeting these inflammatory pathways may represent an effective therapeutic strategy to prevent seizures.

  15. Concussion in professional football: brain responses by finite element analysis: part 9.

    Science.gov (United States)

    Viano, David C; Casson, Ira R; Pellman, Elliot J; Zhang, Liying; King, Albert I; Yang, King H

    2005-11-01

    Brain responses from concussive impacts in National Football League football games were simulated by finite element analysis using a detailed anatomic model of the brain and head accelerations from laboratory reconstructions of game impacts. This study compares brain responses with physician determined signs and symptoms of concussion to investigate tissue-level injury mechanisms. The Wayne State University Head Injury Model (Version 2001) was used because it has fine anatomic detail of the cranium and brain with more than 300,000 elements. It has 15 different material properties for brain and surrounding tissues. The model includes viscoelastic gray and white brain matter, membranes, ventricles, cranium and facial bones, soft tissues, and slip interface conditions between the brain and dura. The cranium of the finite element model was loaded by translational and rotational accelerations measured in Hybrid III dummies from 28 laboratory reconstructions of NFL impacts involving 22 concussions. Brain responses were determined using a nonlinear, finite element code to simulate the large deformation response of white and gray matter. Strain responses occurring early (during impact) and mid-late (after impact) were compared with the signs and symptoms of concussion. Strain concentration "hot spots" migrate through the brain with time. In 9 of 22 concussions, the early strain "hot spots" occur in the temporal lobe adjacent to the impact and migrate to the far temporal lobe after head acceleration. In all cases, the largest strains occur later in the fornix, midbrain, and corpus callosum. They significantly correlated with removal from play, cognitive and memory problems, and loss of consciousness. Dizziness correlated with early strain in the orbital-frontal cortex and temporal lobe. The strain migration helps explain coup-contrecoup injuries. Finite element modeling showed the largest brain deformations occurred after the primary head acceleration. Midbrain strain

  16. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  17. Low Bit Rate Video Coding | Mishra | Nigerian Journal of Technology

    African Journals Online (AJOL)

    ... length bit rate (VLBR) broadly encompasses video coding which mandates a temporal frequency of 10 frames per second (fps) or less. Object-based video coding represents a very promising option for VLBR coding, though the problems of object identification and segmentation need to be addressed by further research.

  18. Glomerular latency coding in artificial olfaction

    Directory of Open Access Journals (Sweden)

    Jaber eAl Yamani

    2012-01-01

    Full Text Available Sensory perception results from the way sensory information is subsequently transformed in the brain. Olfaction is a typical example in which odor representations undergo considerable changes as they pass from olfactory receptor neurons (ORNs to second-order neurons. First, many ORNs expressing the same receptor protein yet presenting heterogeneous dose-response properties converge onto individually identifiable glomeruli. Second, onset latency of glomerular activation is believed to play a role in encoding odor quality and quantity in the context of fast information processing. Taking inspiration from the olfactory pathway, we designed a simple yet robust glomerular latency coding scheme for processing gas sensor data. The proposed bio-inspired approach was evaluated using an in-house Sn02 sensor array. Glomerular convergence was achieved by noting the possible analogy between receptor protein expressed in ORNs and metal catalyst used across the fabricated gas sensor array. Ion implantation was another technique used to account both for sensor heterogeneity and enhanced sensitivity. The response of the gas sensor array was mapped into glomerular latency patterns, whose rank order is concentration-invariant. Gas recognition was achieved by simply looking for a match within a library of spatio-temporal spike fingerprints. Because of its simplicity, this approach enables the integration of sensing and processing onto a single-chip.

  19. Cracking the code of oscillatory activity.

    Directory of Open Access Journals (Sweden)

    Philippe G Schyns

    2011-05-01

    Full Text Available Neural oscillations are ubiquitous measurements of cognitive processes and dynamic routing and gating of information. The fundamental and so far unresolved problem for neuroscience remains to understand how oscillatory activity in the brain codes information for human cognition. In a biologically relevant cognitive task, we instructed six human observers to categorize facial expressions of emotion while we measured the observers' EEG. We combined state-of-the-art stimulus control with statistical information theory analysis to quantify how the three parameters of oscillations (i.e., power, phase, and frequency code the visual information relevant for behavior in a cognitive task. We make three points: First, we demonstrate that phase codes considerably more information (2.4 times relating to the cognitive task than power. Second, we show that the conjunction of power and phase coding reflects detailed visual features relevant for behavioral response--that is, features of facial expressions predicted by behavior. Third, we demonstrate, in analogy to communication technology, that oscillatory frequencies in the brain multiplex the coding of visual features, increasing coding capacity. Together, our findings about the fundamental coding properties of neural oscillations will redirect the research agenda in neuroscience by establishing the differential role of frequency, phase, and amplitude in coding behaviorally relevant information in the brain.

  20. Body language in the brain: constructing meaning from expressive movement

    Science.gov (United States)

    Tipper, Christine M.; Signorini, Giulia; Grafton, Scott T.

    2015-01-01

    This fMRI study investigated neural systems that interpret body language—the meaningful emotive expressions conveyed by body movement. Participants watched videos of performers engaged in modern dance or pantomime that conveyed specific themes such as hope, agony, lust, or exhaustion. We tested whether the meaning of an affectively laden performance was decoded in localized brain substrates as a distinct property of action separable from other superficial features, such as choreography, kinematics, performer, and low-level visual stimuli. A repetition suppression (RS) procedure was used to identify brain regions that decoded the meaningful affective state of a performer, as evidenced by decreased activity when emotive themes were repeated in successive performances. Because the theme was the only feature repeated across video clips that were otherwise entirely different, the occurrence of RS identified brain substrates that differentially coded the specific meaning of expressive performances. RS was observed bilaterally, extending anteriorly along middle and superior temporal gyri into temporal pole, medially into insula, rostrally into inferior orbitofrontal cortex, and caudally into hippocampus and amygdala. Behavioral data on a separate task indicated that interpreting themes from modern dance was more difficult than interpreting pantomime; a result that was also reflected in the fMRI data. There was greater RS in left hemisphere, suggesting that the more abstract metaphors used to express themes in dance compared to pantomime posed a greater challenge to brain substrates directly involved in decoding those themes. We propose that the meaning-sensitive temporal-orbitofrontal regions observed here comprise a superordinate functional module of a known hierarchical action observation network (AON), which is critical to the construction of meaning from expressive movement. The findings are discussed with respect to a predictive coding model of action understanding

  1. Fundamentals of convolutional coding

    CERN Document Server

    Johannesson, Rolf

    2015-01-01

    Fundamentals of Convolutional Coding, Second Edition, regarded as a bible of convolutional coding brings you a clear and comprehensive discussion of the basic principles of this field * Two new chapters on low-density parity-check (LDPC) convolutional codes and iterative coding * Viterbi, BCJR, BEAST, list, and sequential decoding of convolutional codes * Distance properties of convolutional codes * Includes a downloadable solutions manual

  2. Integrative and distinctive coding of visual and conceptual object features in the ventral visual stream.

    Science.gov (United States)

    Martin, Chris B; Douglas, Danielle; Newsome, Rachel N; Man, Louisa Ly; Barense, Morgan D

    2018-02-02

    A significant body of research in cognitive neuroscience is aimed at understanding how object concepts are represented in the human brain. However, it remains unknown whether and where the visual and abstract conceptual features that define an object concept are integrated. We addressed this issue by comparing the neural pattern similarities among object-evoked fMRI responses with behavior-based models that independently captured the visual and conceptual similarities among these stimuli. Our results revealed evidence for distinctive coding of visual features in lateral occipital cortex, and conceptual features in the temporal pole and parahippocampal cortex. By contrast, we found evidence for integrative coding of visual and conceptual object features in perirhinal cortex. The neuroanatomical specificity of this effect was highlighted by results from a searchlight analysis. Taken together, our findings suggest that perirhinal cortex uniquely supports the representation of fully specified object concepts through the integration of their visual and conceptual features. © 2018, Martin et al.

  3. The grounding of temporal metaphors.

    Science.gov (United States)

    Lai, Vicky T; Desai, Rutvik H

    2016-03-01

    Grounded cognition suggests that the processing of conceptual knowledge cued by language relies on the sensory-motor regions. Does temporal language similarly engage brain areas involved in time perception? Participants read sentences that describe the temporal extent of events with motion verbs (The hours crawled until the release of the news) and their static controls. Comparison conditions were fictive motion (The trail crawled until the end of the hills) and literal motion (The caterpillar crawled towards the top of the tree), along with their static controls. Several time sensitive locations, identified using a meta-analysis, showed activation specific to temporal metaphors, including in the left insula, right claustrum, and bilateral posterior superior temporal sulci. Fictive and literal motion contrasts did not show this difference. Fictive motion contrast showed activation in a conceptual motion sensitive area of the left posterior inferior temporal sulcus (ITS). These data suggest that language of time is at least partially grounded in experiential time. In addition, motion semantics has different consequences for events and objects: temporal events become animate, while static entities become motional. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Coding Transparency in Object-Based Video

    DEFF Research Database (Denmark)

    Aghito, Shankar Manuel; Forchhammer, Søren

    2006-01-01

    A novel algorithm for coding gray level alpha planes in object-based video is presented. The scheme is based on segmentation in multiple layers. Different coders are specifically designed for each layer. In order to reduce the bit rate, cross-layer redundancies as well as temporal correlation...... are exploited. Coding results show the superior efficiency of the proposed scheme compared with MPEG-4...

  5. The usefulness of the ivy sign on fluid-attenuated intensity recovery images in improved brain hemodynamic changes after superficial temporal artery-middle cerebral artery anastomosis in adult patients with moyamoya disease.

    Science.gov (United States)

    Lee, Jung Keun; Yoon, Byul Hee; Chung, Seung Young; Park, Moon Sun; Kim, Seong Min; Lee, Do Sung

    2013-10-01

    MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images. We enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery. Ivy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis. After STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.

  6. Brain Basics

    Medline Plus

    Full Text Available ... About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain Brain ... called the hypothalamic-pituitary-adrenal (HPA) axis. Brain Basics in Real Life Brain Basics in Real Life— ...

  7. The place of 'codes' in nonlinear neurodynamics.

    Science.gov (United States)

    Freeman, Walter J

    2007-01-01

    A key problem in cognitive science is to explain the neural mechanisms of the rapid transposition between stimulus energy and abstract concept--between the specific and the generic--in both material and conceptual aspects, not between neural and psychic aspects. Three approaches by researchers to a solution in terms of neural codes are considered. Materialists seek rate and frequency codes in the interspike intervals of trains of action potentials induced by stimuli and carried by topologically organized axonal lines. Cognitivists refer to the symbol grounding problem and search for symbolic codes in firings of hierarchically organized feature-detector neurons of phonemes, lines, odorants, pressures, etc., that object-detector neurons bind into representations of probabilities of stimulus occurrence. Dynamicists seek neural correlates of stimuli and associated behaviors in spatial patterns of oscillatory fields of dendritic activity that self-organize and evolve as trajectories through high-dimensional brain state space; the codes are landscapes of chaotic attractors. Unlike codes in DNA and the periodic table, these codes have neither alphabet nor syntax. They are epistemological metaphors required by experimentalists to measure neural activity and by engineers to model brain functions. Here I review the central neural mechanisms of olfaction as a paradigm for use of codes to explain how brains create cortical activities that mediate sensation, perception, comprehension, prediction, decision, and action or inaction.

  8. Temporal Lobe Epilepsy in Children

    Science.gov (United States)

    Nickels, Katherine C.; Wong-Kisiel, Lily C.; Moseley, Brian D.; Wirrell, Elaine C.

    2012-01-01

    The temporal lobe is a common focus for epilepsy. Temporal lobe epilepsy in infants and children differs from the relatively homogeneous syndrome seen in adults in several important clinical and pathological ways. Seizure semiology varies by age, and the ictal EEG pattern may be less clear cut than what is seen in adults. Additionally, the occurrence of intractable seizures in the developing brain may impact neurocognitive function remote from the temporal area. While many children will respond favorably to medical therapy, those with focal imaging abnormalities including cortical dysplasia, hippocampal sclerosis, or low-grade tumors are likely to be intractable. Expedient workup and surgical intervention in these medically intractable cases are needed to maximize long-term developmental outcome. PMID:22957247

  9. Temporal Lobe Epilepsy in Children

    Directory of Open Access Journals (Sweden)

    Katherine C. Nickels

    2012-01-01

    Full Text Available The temporal lobe is a common focus for epilepsy. Temporal lobe epilepsy in infants and children differs from the relatively homogeneous syndrome seen in adults in several important clinical and pathological ways. Seizure semiology varies by age, and the ictal EEG pattern may be less clear cut than what is seen in adults. Additionally, the occurrence of intractable seizures in the developing brain may impact neurocognitive function remote from the temporal area. While many children will respond favorably to medical therapy, those with focal imaging abnormalities including cortical dysplasia, hippocampal sclerosis, or low-grade tumors are likely to be intractable. Expedient workup and surgical intervention in these medically intractable cases are needed to maximize long-term developmental outcome.

  10. Neural dynamics of reward probability coding: a Magnetoencephalographic study in humans

    Directory of Open Access Journals (Sweden)

    Julie eThomas

    2013-11-01

    Full Text Available Prediction of future rewards and discrepancy between actual and expected outcomes (prediction error are crucial signals for adaptive behavior. In humans, a number of fMRI studies demonstrated that reward probability modulates these two signals in a large brain network. Yet, the spatio-temporal dynamics underlying the neural coding of reward probability remains unknown. Here, using magnetoencephalography, we investigated the neural dynamics of prediction and reward prediction error computations while subjects learned to associate cues of slot machines with monetary rewards with different probabilities. We showed that event-related magnetic fields (ERFs arising from the visual cortex coded the expected reward value 155 ms after the cue, demonstrating that reward value signals emerge early in the visual stream. Moreover, a prediction error was reflected in ERF peaking 300 ms after the rewarded outcome and showing decreasing amplitude with higher reward probability. This prediction error signal was generated in a network including the anterior and posterior cingulate cortex. These findings pinpoint the spatio-temporal characteristics underlying reward probability coding. Together, our results provide insights into the neural dynamics underlying the ability to learn probabilistic stimuli-reward contingencies.

  11. Brain mechanisms underlying human communication

    Directory of Open Access Journals (Sweden)

    Matthijs L Noordzij

    2009-07-01

    Full Text Available Human communication has been described as involving the coding-decoding of a conventional symbol system, which could be supported by parts of the human motor system (i.e. the “mirror neurons system”. However, this view does not explain how these conventions could develop in the first place. Here we target the neglected but crucial issue of how people organize their non-verbal behavior to communicate a given intention without pre-established conventions. We have measured behavioral and brain responses in pairs of subjects during communicative exchanges occurring in a real, interactive, on-line social context. In two fMRI studies, we found robust evidence that planning new communicative actions (by a sender and recognizing the communicative intention of the same actions (by a receiver relied on spatially overlapping portions of their brains (the right posterior superior temporal sulcus. The response of this region was lateralized to the right hemisphere, modulated by the ambiguity in meaning of the communicative acts, but not by their sensorimotor complexity. These results indicate that the sender of a communicative signal uses his own intention recognition system to make a prediction of the intention recognition performed by the receiver. This finding supports the notion that our communicative abilities are distinct from both sensorimotor processes and language abilities.

  12. A thesaurus for a neural population code.

    Science.gov (United States)

    Ganmor, Elad; Segev, Ronen; Schneidman, Elad

    2015-09-08

    Information is carried in the brain by the joint spiking patterns of large groups of noisy, unreliable neurons. This noise limits the capacity of the neural code and determines how information can be transmitted and read-out. To accurately decode, the brain must overcome this noise and identify which patterns are semantically similar. We use models of network encoding noise to learn a thesaurus for populations of neurons in the vertebrate retina responding to artificial and natural videos, measuring the similarity between population responses to visual stimuli based on the information they carry. This thesaurus reveals that the code is organized in clusters of synonymous activity patterns that are similar in meaning but may differ considerably in their structure. This organization is highly reminiscent of the design of engineered codes. We suggest that the brain may use this structure and show how it allows accurate decoding of novel stimuli from novel spiking patterns.

  13. Affine Grassmann codes

    DEFF Research Database (Denmark)

    Høholdt, Tom; Beelen, Peter; Ghorpade, Sudhir Ramakant

    2010-01-01

    We consider a new class of linear codes, called affine Grassmann codes. These can be viewed as a variant of generalized Reed-Muller codes and are closely related to Grassmann codes.We determine the length, dimension, and the minimum distance of any affine Grassmann code. Moreover, we show...

  14. BrainNet Europe's Code of Conduct for brain banking

    NARCIS (Netherlands)

    Klioueva, Natasja M; Rademaker, Marleen C; Dexter, David T; Al-Sarraj, Safa; Seilhean, Danielle; Streichenberger, Nathalie; Schmitz, Peer; Bell, Jeanne E; Ironside, James W; Arzberger, Thomas; Huitinga, I.

    Research utilizing human tissue and its removal at post-mortem has given rise to many controversies in the media and posed many dilemmas in the fields of law and ethics. The law often lacks clear instructions and unambiguous guidelines. The absence of a harmonized international legislation with

  15. Rhythmic complexity and predictive coding: A novel approach to modeling rhythm and meter perception in music

    Directory of Open Access Journals (Sweden)

    Peter eVuust

    2014-10-01

    Full Text Available Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of predictive coding, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain’s Bayesian minimization of the error between the input to the brain and the brain’s prior expectations. Third, we develop a predictive coding model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard (‘rhythm’ and the brain’s anticipatory structuring of music (‘meter’. Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the predictive coding theory. We argue that musical rhythm exploits the brain’s general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms.

  16. Turbo Codes Extended with Outer BCH Code

    DEFF Research Database (Denmark)

    Andersen, Jakob Dahl

    1996-01-01

    The "error floor" observed in several simulations with the turbo codes is verified by calculation of an upper bound to the bit error rate for the ensemble of all interleavers. Also an easy way to calculate the weight enumerator used in this bound is presented. An extended coding scheme is propose...... including an outer BCH code correcting a few bit errors.......The "error floor" observed in several simulations with the turbo codes is verified by calculation of an upper bound to the bit error rate for the ensemble of all interleavers. Also an easy way to calculate the weight enumerator used in this bound is presented. An extended coding scheme is proposed...

  17. Rateless feedback codes

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Koike-Akino, Toshiaki; Orlik, Philip

    2012-01-01

    This paper proposes a concept called rateless feedback coding. We redesign the existing LT and Raptor codes, by introducing new degree distributions for the case when a few feedback opportunities are available. We show that incorporating feedback to LT codes can significantly decrease both...... the coding overhead and the encoding/decoding complexity. Moreover, we show that, at the price of a slight increase in the coding overhead, linear complexity is achieved with Raptor feedback coding....

  18. Generalized concatenated quantum codes

    Science.gov (United States)

    Grassl, Markus; Shor, Peter; Smith, Graeme; Smolin, John; Zeng, Bei

    2009-05-01

    We discuss the concept of generalized concatenated quantum codes. This generalized concatenation method provides a systematical way for constructing good quantum codes, both stabilizer codes and nonadditive codes. Using this method, we construct families of single-error-correcting nonadditive quantum codes, in both binary and nonbinary cases, which not only outperform any stabilizer codes for finite block length but also asymptotically meet the quantum Hamming bound for large block length.

  19. Music and the auditory brain: where is the connection?

    Directory of Open Access Journals (Sweden)

    Israel eNelken

    2011-09-01

    Full Text Available Sound processing by the auditory system is understood in unprecedented details, even compared with sensory coding in the visual system. Nevertheless, we don't understand yet the way in which some of the simplest perceptual properties of sounds are coded in neuronal activity. This poses serious difficulties for linking neuronal responses in the auditory system and music processing, since music operates on abstract representations of sounds. Paradoxically, although perceptual representations of sounds most probably occur high in auditory system or even beyond it, neuronal responses are strongly affected by the temporal organization of sound streams even in subcortical stations. Thus, to the extent that music is organized sound, it is the organization, rather than the sound, which is represented first in the auditory brain.

  20. Advanced video coding systems

    CERN Document Server

    Gao, Wen

    2015-01-01

    This comprehensive and accessible text/reference presents an overview of the state of the art in video coding technology. Specifically, the book introduces the tools of the AVS2 standard, describing how AVS2 can help to achieve a significant improvement in coding efficiency for future video networks and applications by incorporating smarter coding tools such as scene video coding. Topics and features: introduces the basic concepts in video coding, and presents a short history of video coding technology and standards; reviews the coding framework, main coding tools, and syntax structure of AV

  1. Coding for dummies

    CERN Document Server

    Abraham, Nikhil

    2015-01-01

    Hands-on exercises help you learn to code like a pro No coding experience is required for Coding For Dummies,your one-stop guide to building a foundation of knowledge inwriting computer code for web, application, and softwaredevelopment. It doesn't matter if you've dabbled in coding or neverwritten a line of code, this book guides you through the basics.Using foundational web development languages like HTML, CSS, andJavaScript, it explains in plain English how coding works and whyit's needed. Online exercises developed by Codecademy, a leading online codetraining site, help hone coding skill

  2. 3D Scan-Based Wavelet Transform and Quality Control for Video Coding

    OpenAIRE

    Parisot Christophe; Antonini Marc; Barlaud Michel

    2003-01-01

    Wavelet coding has been shown to achieve better compression than DCT coding and moreover allows scalability. 2D DWT can be easily extended to 3D and thus applied to video coding. However, 3D subband coding of video suffers from two drawbacks. The first is the amount of memory required for coding large 3D blocks; the second is the lack of temporal quality due to the sequence temporal splitting. In fact, 3D block-based video coders produce jerks. They appear at blocks temporal borders during v...

  3. Brain Basics

    Medline Plus

    Full Text Available ... Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video Welcome. Brain Basics provides information on how the brain works, how mental illnesses ...

  4. Brain Basics

    Science.gov (United States)

    ... Events About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain ... to mental disorders, such as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are ...

  5. Brain Basics

    Medline Plus

    Full Text Available ... Events About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain ... to mental disorders, such as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are ...

  6. Brain Basics

    Medline Plus

    Full Text Available ... Brain Basics provides information on how the brain works, how mental illnesses are disorders of the brain, ... learning more about how the brain grows and works in healthy people, and how normal brain development ...

  7. Ecoacoustic codes and ecological complexity.

    Science.gov (United States)

    Farina, Almo

    2018-02-01

    Multi-layer communication and sensing network assures the exchange of relevant information between animals and their umwelten, imparting complexity to the ecological systems. Individual soniferous species, the acoustic community, and soundscape are the three main operational levels that comprise this multi-layer network. Acoustic adaptation and acoustic niche are two more important mechanisms that regulate the acoustic performances at the first level while the acoustic community model explains the complexity of the interspecific acoustic network at the second level. Acoustic habitat and ecoacoustic events are two of the most relevant mechanisms that operate at the third level. The exchange of ecoacoustic information on each of these levels is assured by ecoacoustic codes. At the level of individual sonifeorus species, a dyadic intraspecific exchange of information is established between an emitter and a receiver. Ecoacoustic codes discriminate, identify, and label specific signals that pertain to the theme, variation, motif repetition, and intensity of signals. At the acoustic community level, a voluntarily or involuntarily communication is established between networks of interspecific emitters and receivers. Ecoacoustic codes at this level transmit information (e.g., recognition of predators, location of food sources, availability and location of refuges) between one species and the acoustically interacting community and impart cohesion to interspecific assemblages. At the soundscape level, acoustic information is transferred from a mosaic of geophonies, biophonies, and technophonies to different species that discriminate meaningful ecoacoustic events and their temporal dynamics during habitat selection processes. Ecoacoustic codes at this level operate on a limited set of signals from the environmental acoustic dynamic that are heterogeneous in time and space, and these codes are interpreted differently according to the species during habitat selection and the

  8. Discussion on LDPC Codes and Uplink Coding

    Science.gov (United States)

    Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

    2007-01-01

    This slide presentation reviews the progress that the workgroup on Low-Density Parity-Check (LDPC) for space link coding. The workgroup is tasked with developing and recommending new error correcting codes for near-Earth, Lunar, and deep space applications. Included in the presentation is a summary of the technical progress of the workgroup. Charts that show the LDPC decoder sensitivity to symbol scaling errors are reviewed, as well as a chart showing the performance of several frame synchronizer algorithms compared to that of some good codes and LDPC decoder tests at ESTL. Also reviewed is a study on Coding, Modulation, and Link Protocol (CMLP), and the recommended codes. A design for the Pseudo-Randomizer with LDPC Decoder and CRC is also reviewed. A chart that summarizes the three proposed coding systems is also presented.

  9. Language brain dominance in patients with refractory temporal lobe epilepsy: a comparative study between functional magnetic resonance imaging and dichotic listening test Determinação de dominância cerebral para linguagem em pacientes com epilepsia refratária de lobo temporal: estudo comparativo entre ressonância magnética funcional e teste de escuta dicótica

    Directory of Open Access Journals (Sweden)

    Denise Ren da Fontoura

    2008-03-01

    Full Text Available PURPOSE: To identify brain dominance for language functions with DLT and correlate these results with those obtained from fMRI in patients suffering from intractable temporal lobe epilepsy. METHOD: This study reports on 13 patients who underwent pre-surgical epileptic evaluation between April and October 2004 at the Epilepsy Surgery Program, Hospital Sao Lucas, PUCRS. In DLT, dominance was assessed through a consonant-vowel task, whereas in fMRI patients performed a verb generation task. RESULTS: Our results identified a correlation between the fMRI lateralization index and the DLT ear predominance index and reply difference index (r=0.6, p=0.02; Pearson Correlation Coefficient, showing positive correlation between results obtained from fMRI and DLT. CONCLUSION: DLT was found to significantly correlate with fMRI. These findings indicate that DLT (a non-invasive procedure could be a useful tool to evaluate language brain dominance in pre-surgical epileptic patients as it is cheaper to perform than fMRI.OBJETIVO: Identificar a dominância cerebral para funções de linguagem através do teste de escuta dicótica (TED e correlacionar com os resultados de ressonância magnética funcional (RMf em pacientes com epilepsia refratária de lobo temporal. MÉTODO: Foram estudados 13 pacientes com epilepsia refratária de lobo temporal, que realizaram avaliações pré-cirúrgicas no período de abril a outubro de 2004 no Programa de Cirurgia de Epilepsia do Hospital São Lucas da PUCRS. Realizada investigação da dominância hemisférica para linguagem através do TED Consoante-Vogal e da RMf pela geração de verbos. RESULTADOS: Verificou-se a existência de correlação entre os índices de lateralidade (RMf e os índices de predomínio de orelha e de diferença de resposta (TED (r=0,6, p=0,02. CONCLUSÃO: Existe correlação entre os resultados obtidos através da RMf (índice de lateralidade e do TED (índice de predomínio de orelha e índice de

  10. Locally orderless registration code

    DEFF Research Database (Denmark)

    2012-01-01

    This is code for the TPAMI paper "Locally Orderless Registration". The code requires intel threadding building blocks installed and is provided for 64 bit on mac, linux and windows.......This is code for the TPAMI paper "Locally Orderless Registration". The code requires intel threadding building blocks installed and is provided for 64 bit on mac, linux and windows....

  11. Avaliação de foco epileptogênico do lobo temporal: correlação entre SPECT ictal, ressonância magnética e ressonância magnética com espectroscopia de prótons Evaluation of epileptogenic focus in temporal lobe: correlation between ictal brain SPECT, magnetic resonance imaging and magnetic resonance spectroscopy

    Directory of Open Access Journals (Sweden)

    Maria Elena Martins Diegues

    2004-02-01

    Full Text Available O objetivo deste trabalho foi determinar a existência de concordância entre os métodos radioisotópico e radiológico e, em caso positivo, avaliar a utilidade do SPECT ictal na determinação do foco epileptogênico. Foram realizados SPECT ictal, ressonância magnética (RM e ressonância magnética com espectroscopia de prótons (RME em seis pacientes com epilepsia de lobo temporal refratária. O SPECT ictal foi realizado após a retirada das drogas antiepilépticas durante monitoramento por vídeo-EEG, utilizando-se o 99mTc-ECD, administrado aos pacientes no início da crise. As imagens de RM foram obtidas em T1, T2 e FLAIR, com cortes de 3 e 5 mm de espessura, e a RME foi realizada com técnica PRESS, com voxel único posicionado no hipocampo, bilateralmente. A análise estatística incluiu os valores de Kappa (k, erro-padrão (ep e o nível de significância (p para a lateralização do foco. Os achados foram analisados com base na localização por EEG da descarga ictal, no tempo de duração da crise (109-280 s; média: 152 s e no tempo de administração do traçador (30-262 s; média: 96 s. Obtivemos dados correlatos em quatro pacientes (67%, com valores de k = 0,67, ep = 0,38 e p = 0,041. Concluímos que existe concordância entre SPECT ictal, RM e RME, e a utilidade do procedimento radioisotópico está relacionada aos casos em que o EEG não é diagnóstico e quando há discordância ou indefinição diagnóstica na análise comparativa entre EEG, RM e RME.The purpose of this study was to determine the degree of concordance between radiological and radioisotopic methods and, if positive, to evaluate the usefulness of ictal SPECT in the localization of the epileptogenic focus. Ictal brain SPECT, magnetic resonance imaging (MRI and magnetic resonance spectroscopy (MRS were performed on six patients with refractory temporal lobe epilepsy. Ictal SPECT was performed after withdrawal of the anti-epileptogenic drugs during video

  12. Algebraic geometric codes

    Science.gov (United States)

    Shahshahani, M.

    1991-01-01

    The performance characteristics are discussed of certain algebraic geometric codes. Algebraic geometric codes have good minimum distance properties. On many channels they outperform other comparable block codes; therefore, one would expect them eventually to replace some of the block codes used in communications systems. It is suggested that it is unlikely that they will become useful substitutes for the Reed-Solomon codes used by the Deep Space Network in the near future. However, they may be applicable to systems where the signal to noise ratio is sufficiently high so that block codes would be more suitable than convolutional or concatenated codes.

  13. Monomial-like codes

    CERN Document Server

    Martinez-Moro, Edgar; Ozbudak, Ferruh; Szabo, Steve

    2010-01-01

    As a generalization of cyclic codes of length p^s over F_{p^a}, we study n-dimensional cyclic codes of length p^{s_1} X ... X p^{s_n} over F_{p^a} generated by a single "monomial". Namely, we study multi-variable cyclic codes of the form in F_{p^a}[x_1...x_n] / . We call such codes monomial-like codes. We show that these codes arise from the product of certain single variable codes and we determine their minimum Hamming distance. We determine the dual of monomial-like codes yielding a parity check matrix. We also present an alternative way of constructing a parity check matrix using the Hasse derivative. We study the weight hierarchy of certain monomial like codes. We simplify an expression that gives us the weight hierarchy of these codes.

  14. QR Codes 101

    Science.gov (United States)

    Crompton, Helen; LaFrance, Jason; van 't Hooft, Mark

    2012-01-01

    A QR (quick-response) code is a two-dimensional scannable code, similar in function to a traditional bar code that one might find on a product at the supermarket. The main difference between the two is that, while a traditional bar code can hold a maximum of only 20 digits, a QR code can hold up to 7,089 characters, so it can contain much more…

  15. 3D Scan-Based Wavelet Transform and Quality Control for Video Coding

    Directory of Open Access Journals (Sweden)

    Parisot Christophe

    2003-01-01

    Full Text Available Wavelet coding has been shown to achieve better compression than DCT coding and moreover allows scalability. 2D DWT can be easily extended to 3D and thus applied to video coding. However, 3D subband coding of video suffers from two drawbacks. The first is the amount of memory required for coding large 3D blocks; the second is the lack of temporal quality due to the sequence temporal splitting. In fact, 3D block-based video coders produce jerks. They appear at blocks temporal borders during video playback. In this paper, we propose a new temporal scan-based wavelet transform method for video coding combining the advantages of wavelet coding (performance, scalability with acceptable reduced memory requirements, no additional CPU complexity, and avoiding jerks. We also propose an efficient quality allocation procedure to ensure a constant quality over time.

  16. 3D Scan-Based Wavelet Transform and Quality Control for Video Coding

    Science.gov (United States)

    Parisot, Christophe; Antonini, Marc; Barlaud, Michel

    2003-12-01

    Wavelet coding has been shown to achieve better compression than DCT coding and moreover allows scalability. 2D DWT can be easily extended to 3D and thus applied to video coding. However, 3D subband coding of video suffers from two drawbacks. The first is the amount of memory required for coding large 3D blocks; the second is the lack of temporal quality due to the sequence temporal splitting. In fact, 3D block-based video coders produce jerks. They appear at blocks temporal borders during video playback. In this paper, we propose a new temporal scan-based wavelet transform method for video coding combining the advantages of wavelet coding (performance, scalability) with acceptable reduced memory requirements, no additional CPU complexity, and avoiding jerks. We also propose an efficient quality allocation procedure to ensure a constant quality over time.

  17. The polyphonic brain

    DEFF Research Database (Denmark)

    Sturm, Irene; Treder, Matthias S.; Dähne, Sven

    Rapid changes in the stimulus envelope (indicating tone onsets) elicit an N1-P2 ERP response, as has been shown for clicks and sine waves, musical tones and for speech. Canonical Correlation Analysis with temporal embedding (tkCCA), a multivariate correlation-based method, allows to extract brain...

  18. An efficient coding theory for a dynamic trajectory predicts non-uniform allocation of entorhinal grid cells to modules

    Science.gov (United States)

    Mosheiff, Noga; Agmon, Haggai; Moriel, Avraham

    2017-01-01

    Grid cells in the entorhinal cortex encode the position of an animal in its environment with spatially periodic tuning curves with different periodicities. Recent experiments established that these cells are functionally organized in discrete modules with uniform grid spacing. Here we develop a theory for efficient coding of position, which takes into account the temporal statistics of the animal’s motion. The theory predicts a sharp decrease of module population sizes with grid spacing, in agreement with the trend seen in the experimental data. We identify a simple scheme for readout of the grid cell code by neural circuitry, that can match in accuracy the optimal Bayesian decoder. This readout scheme requires persistence over different timescales, depending on the grid cell module. Thus, we propose that the brain may employ an efficient representation of position which takes advantage of the spatiotemporal statistics of the encoded variable, in similarity to the principles that govern early sensory processing. PMID:28628647

  19. The human infant brain: A neural architecture able to learn language.

    Science.gov (United States)

    Dehaene-Lambertz, Ghislaine

    2017-02-01

    To understand the type of neural computations that may explain how human infants acquire their native language in only a few months, the study of their neural architecture is necessary. The development of brain imaging techniques has opened the possibilities of studying human infants without discomfort, and although these studies are still sparse, several characteristics are noticeable in the human infant's brain: first, parallel and hierarchical processing pathways are observed before intense exposure to speech with an efficient temporal coding in the left hemisphere and, second, frontal regions are involved from the start in infants' cognition. These observations are certainly not sufficient to explain language acquisition but illustrate a new approach that relies on a better description of infants' brain activity during linguistic tasks, which is compared to results in animals and human adults to clarify the neural bases of language in humans.

  20. Spatio temporal media components for neurofeedback

    DEFF Research Database (Denmark)

    Jensen, Camilla Birgitte Falk; Petersen, Michael Kai; Larsen, Jakob Eg

    2013-01-01

    A class of Brain Computer Interfaces (BCI) involves interfaces for neurofeedback training, where a user can learn to self-regulate brain activity based on real-time feedback. These particular interfaces are constructed from audio-visual components and temporal settings, which appear to have...... a strong influence on the ability to control brain activity. Therefore, identifying the different interface components and exploring their individual effects might be key for constructing new interfaces that support more efficient neurofeedback training. We discuss experiments involving two different...

  1. Towards General Temporal Aggregation

    DEFF Research Database (Denmark)

    Boehlen, Michael H.; Gamper, Johann; Jensen, Christian Søndergaard

    2008-01-01

    Most database applications manage time-referenced, or temporal, data. Temporal data management is difficult when using conventional database technology, and many contributions have been made for how to better model, store, and query temporal data. Temporal aggregation illustrates well the problem...

  2. Osteoradionecrosis of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Fujimori, Masato; Koyama, Yukiko; Enomoto, Fuyuki; Ichikawa, Ginichiro [Juntendo Univ., Tokyo (Japan). School of Medicine

    2002-08-01

    We report a case of temporal bone necrosis that emerged after radiotherapy for epipharyngeal carcinoma performed 13 years ago. The patient was a 51-year-old male. His major complaint was left facial swelling. The patient underwent chemotherapy and radiotherapy (Co 60, 6120 rad), as the treatment of that period, for epipharyngeal carcinoma from September 30, 1986 to January 31, 1987. He also underwent lobectomy of the left temporal lobe in brain surgery for left temporal lobe necrosis in August, 1989. After that operation, we saw constriction in his left external acoustic meatus and continued the follow-up. On October 22, 1999 he felt a left facial swelling. We found skin defects and ulcer formation in the front part of his left ear. Although we administered an antiseptic and antibiotic to the diseased area, his condition did not improve. He was hospitalized for the purpose of undergoing medical treatment on January 6, 2000. We found extensive skin necrosis and defects in his left auricular area. The corrupted temporal bone reached the zygomatic, the bone department external acoustic meatus and the mastoid process was exposing. We performed debridement of the diseased area on January 19, 2000. On February 23, we performed reconstruction by left trapezius muscle flap after debridement once again. One year after the operation, the flap was completely incorporated. (author)

  3. Comprehensive regional and temporal gene expression profiling of the rat brain during the first 24 h after experimental stroke identifies dynamic ischemia-induced gene expression patterns, and reveals a biphasic activation of genes in surviving tissue

    DEFF Research Database (Denmark)

    Rickhag, Karl Mattias; Wieloch, Tadeusz; Gidö, Gunilla

    2006-01-01

    -dehydrogenase1, and Choline kinase) or cell death-regulating genes such as mitochondrial CLIC. We conclude that a biphasic transcriptional up-regulation of the brain-derived neurotrophic factor (BDNF)-G-protein coupled receptor (GPCR)-mitogen-activated protein (MAP) kinase signaling pathways occurs in surviving...... tissue, concomitant with a progressive and persistent activation of cell proliferation signifying tissue regeneration, which provide the means for cell survival and postischemic brain plasticity.......In order to identify biological processes relevant for cell death and survival in the brain following stroke, the postischemic brain transcriptome was studied by a large-scale cDNA array analysis of three peri-infarct brain regions at eight time points during the first 24 h of reperfusion following...

  4. Multiband multislice GE‐EPI at 7 tesla, with 16‐fold acceleration using partial parallel imaging with application to high spatial and temporal whole‐brain fMRI

    National Research Council Canada - National Science Library

    Moeller, Steen; Yacoub, Essa; Olman, Cheryl A; Auerbach, Edward; Strupp, John; Harel, Noam; Uğurbil, Kâmil

    2010-01-01

    ... ‐space coverage in the phase‐encode direction, was applied to human gradient echo functional MRI at 7 T for increased volumetric coverage and concurrent high spatial and temporal resolution...

  5. Brain herniation

    Science.gov (United States)

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  6. Clipboard: Neural coding of temporal information and its topography ...

    Indian Academy of Sciences (India)

    2010-11-09

    Nov 9, 2010 ... Thomas A Terleph1 Raphael Pinaud2. Department of Biology, Sacred Heart University, Fairfield, CT 06825, USA; Departments of Physiology, Geriatric Medicine and Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA ...

  7. Interactive online brain shape visualization

    Directory of Open Access Journals (Sweden)

    Anisha Keshavan

    2017-02-01

    Full Text Available The open-source Mindboggle package improves the labeling and morphometry estimates of brain imaging data. At the 2015 Brainhack event, we developed a web-based, interactive, brain shape visualization of Mindboggle outputs. The application links a 3D brain visualization with boxplots that describe shape measures across a selected cortical label. The code is freely available at http://www.github.com/akeshavan/roygbiv and a demo is online at http://roygbiv.mindboggle.info.

  8. Temporal hypometabolism at the onset of cryptogenic temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Matheja, P.; Kuwert, T.; Weckesser, M.; Schober, O. [Dept. of Nuclear Medicine, Muenster Univ. (Germany); Luedemann, P.; Kellinghaus, C.; Diehl, B.; Ringelstein, E.B. [Dept. of Neurology, Muenster Univ. (Germany); Schuierer, G. [Dept. of Clinical Radiology, Muenster Univ. (Germany)

    2001-05-01

    Most patients with intractable temporal lobe epilepsy (TLE) exhibit temporal glucose hypometabolism. The reasons for the development of this abnormality are as yet unclear. The current notion is that an initial injury causes seizures, which in turn give rise to hypometabolism. The aim of this study was to assess whether temporal reductions in glucose metabolism in non-lesional TLE are the result of repeated seizures or whether hypometabolism represents an initial disturbance at the onset of disease. Glucose consumption was assessed with fluorine-18 fluorodeoxyglucose positron emission tomography ({sup 18}F-FDG PET) in 62 patients with cryptogenic non-refractory TLE in different stages of disease. Twelve subjects without neurological illness served as controls. Patients with onset of epilepsy at least 3 years prior to the PET scan were defined as having chronic TLE. Using this criterion, the whole patient cohort included 27 patients with de novo TLE and 35 patients with chronic TLE. The groups were matched for age and sex. The appearance of high-resolution magnetic resonance images of the brain was unremarkable in all patients. In the total cohort, number, duration and frequency of seizures had a significant relation to the magnitude of hypometabolism. Temporal hypometabolism was exhibited by 26 of the 62 patients (42%), including 8 out of 27 (30%) with newly diagnosed TLE and 18 out of 35 (51%) with chronic TLE. The disturbances were more extensive and more severe in patients with chronic TLE. It is concluded that temporal hypometabolism may already be present at the onset of TLE, but is less frequent and less severe in newly diagnosed than in chronic TLE. The metabolic disturbance correlates with the number of seizures. These findings suggest that an initial dysfunction is present in a considerable number of patients and that hypometabolism is worsened by continuing epileptic activity. (orig.)

  9. Brain Basics

    Medline Plus

    Full Text Available ... PDF, 10 pages) Introduction Watch the Brain Basics video Welcome. Brain Basics provides information on how the brain works, how mental illnesses are disorders of the brain, and ongoing research that helps ...

  10. Brain Basics

    Medline Plus

    Full Text Available ... Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video Welcome. Brain Basics ... depression experience when starting treatment. Gene Studies ... medication. This information may someday make it possible to predict who ...

  11. Brain Basics

    Medline Plus

    Full Text Available ... Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video Welcome. Brain Basics ... fear hub," which activates our natural "fight-or-flight" response to confront or escape from a dangerous ...

  12. Brain Lesions

    Science.gov (United States)

    Symptoms Brain lesions By Mayo Clinic Staff A brain lesion is an abnormality seen on a brain-imaging test, such as ... tomography (CT). On CT or MRI scans, brain lesions appear as dark or light spots that don' ...

  13. Brain Basics

    Medline Plus

    Full Text Available ... Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a middle- ... than ever before. Brain Imaging Using brain imaging technologies such as magnetic resonance imaging (MRI), which uses ...

  14. TIPONLINE Code Table

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Coded items are entered in the tiponline data entry program. The codes and their explanations are necessary in order to use the data

  15. Coding for optical channels

    CERN Document Server

    Djordjevic, Ivan; Vasic, Bane

    2010-01-01

    This unique book provides a coherent and comprehensive introduction to the fundamentals of optical communications, signal processing and coding for optical channels. It is the first to integrate the fundamentals of coding theory and optical communication.

  16. ARC Code TI: ROC Curve Code Augmentation

    Data.gov (United States)

    National Aeronautics and Space Administration — ROC (Receiver Operating Characteristic) curve Code Augmentation was written by Rodney Martin and John Stutz at NASA Ames Research Center and is a modification of ROC...

  17. Neurofeedback tunes scale-free dynamics in spontaneous brain activity

    NARCIS (Netherlands)

    Ros, T.; Frewen, P.A.; Thé berge, J.; Michela, A.; Kluetsch, R.C.; Mü ller, A.; Candrian, G.; Jetly, R.; Vuilleumier, P.; Lanius, R.

    2017-01-01

    Brain oscillations exhibit long-range temporal correlations (LRTCs), which reflect the regularity of their fluctuations: low values representing more random (decorrelated) while high values more persistent (correlated) dynamics. LRTCs constitute supporting evidence that the brain operates near

  18. Temporal Feature Integration for Music Organisation

    DEFF Research Database (Denmark)

    Meng, Anders

    2006-01-01

    This Ph.D. thesis focuses on temporal feature integration for music organisation. Temporal feature integration is the process of combining all the feature vectors of a given time-frame into a single new feature vector in order to capture relevant information in the frame. Several existing methods...... for handling sequences of features are formulated in the temporal feature integration framework. Two datasets for music genre classification have been considered as valid test-beds for music organisation. Human evaluations of these, have been obtained to access the subjectivity on the datasets. Temporal...... feature integration has been used for ranking various short-time features at different time-scales. This include short-time features such as the Mel frequency cepstral coefficients (MFCC), linear predicting coding coefficients (LPC) and various MPEG-7 short-time features. The ‘consensus sensitivity...

  19. Gauge color codes

    DEFF Research Database (Denmark)

    Bombin Palomo, Hector

    2015-01-01

    Color codes are topological stabilizer codes with unusual transversality properties. Here I show that their group of transversal gates is optimal and only depends on the spatial dimension, not the local geometry. I also introduce a generalized, subsystem version of color codes. In 3D they allow...

  20. Refactoring test code

    NARCIS (Netherlands)

    A. van Deursen (Arie); L.M.F. Moonen (Leon); A. van den Bergh; G. Kok

    2001-01-01

    textabstractTwo key aspects of extreme programming (XP) are unit testing and merciless refactoring. Given the fact that the ideal test code / production code ratio approaches 1:1, it is not surprising that unit tests are being refactored. We found that refactoring test code is different from

  1. Harmonic Brain Modes: A Unifying Framework for Linking Space and Time in Brain Dynamics.

    Science.gov (United States)

    Atasoy, Selen; Deco, Gustavo; Kringelbach, Morten L; Pearson, Joel

    2017-09-01

    A fundamental characteristic of spontaneous brain activity is coherent oscillations covering a wide range of frequencies. Interestingly, these temporal oscillations are highly correlated among spatially distributed cortical areas forming structured correlation patterns known as the resting state networks, although the brain is never truly at "rest." Here, we introduce the concept of harmonic brain modes-fundamental building blocks of complex spatiotemporal patterns of neural activity. We define these elementary harmonic brain modes as harmonic modes of structural connectivity; that is, connectome harmonics, yielding fully synchronous neural activity patterns with different frequency oscillations emerging on and constrained by the particular structure of the brain. Hence, this particular definition implicitly links the hitherto poorly understood dimensions of space and time in brain dynamics and its underlying anatomy. Further we show how harmonic brain modes can explain the relationship between neurophysiological, temporal, and network-level changes in the brain across different mental states ( wakefulness, sleep, anesthesia, psychedelic). Notably, when decoded as activation of connectome harmonics, spatial and temporal characteristics of neural activity naturally emerge from the interplay between excitation and inhibition and this critical relation fits the spatial, temporal, and neurophysiological changes associated with different mental states. Thus, the introduced framework of harmonic brain modes not only establishes a relation between the spatial structure of correlation patterns and temporal oscillations (linking space and time in brain dynamics), but also enables a new dimension of tools for understanding fundamental principles underlying brain dynamics in different states of consciousness.

  2. The Procions` code; Le code Procions

    Energy Technology Data Exchange (ETDEWEB)

    Deck, D.; Samba, G.

    1994-12-19

    This paper presents a new code to simulate plasmas generated by inertial confinement. This multi-kinds kinetic code is done with no angular approximation concerning ions and will work in plan and spherical geometry. First, the physical model is presented, using Fokker-Plank. Then, the numerical model is introduced in order to solve the Fokker-Plank operator under the Rosenbluth form. At the end, several numerical tests are proposed. (TEC). 17 refs., 27 figs.

  3. Brain Basics

    Medline Plus

    Full Text Available ... Mental Illnesses Clinical Trials Outreach Research Priorities Funding Labs at NIMH News & Events About Us Home > Health & Education > Educational Resources Brain Basics Introduction The Growing Brain The Working Brain Brain Basics in Real Life Brain Research Glossary Brain Basics (PDF, 10 pages) ...

  4. Updating representations of temporal intervals.

    Science.gov (United States)

    Danckert, James; Anderson, Britt

    2015-12-01

    Effectively engaging with the world depends on accurate representations of the regularities that make up that world-what we call mental models. The success of any mental model depends on the ability to adapt to changes-to 'update' the model. In prior work, we have shown that damage to the right hemisphere of the brain impairs the ability to update mental models across a range of tasks. Given the disparate nature of the tasks we have employed in this prior work (i.e. statistical learning, language acquisition, position priming, perceptual ambiguity, strategic game play), we propose that a cognitive module important for updating mental representations should be generic, in the sense that it is invoked across multiple cognitive and perceptual domains. To date, the majority of our tasks have been visual in nature. Given the ubiquity and import of temporal information in sensory experience, we examined the ability to build and update mental models of time. We had healthy individuals complete a temporal prediction task in which intervals were initially drawn from one temporal range before an unannounced switch to a different range of intervals. Separate groups had the second range of intervals switch to one that contained either longer or shorter intervals than the first range. Both groups showed significant positive correlations between perceptual and prediction accuracy. While each group updated mental models of temporal intervals, those exposed to shorter intervals did so more efficiently. Our results support the notion of generic capacity to update regularities in the environment-in this instance based on temporal information. The task developed here is well suited to investigations in neurological patients and in neuroimaging settings.

  5. pycola: N-body COLA method code

    Science.gov (United States)

    Tassev, Svetlin; Eisenstein, Daniel J.; Wandelt, Benjamin D.; Zaldarriagag, Matias

    2015-09-01

    pycola is a multithreaded Python/Cython N-body code, implementing the Comoving Lagrangian Acceleration (COLA) method in the temporal and spatial domains, which trades accuracy at small-scales to gain computational speed without sacrificing accuracy at large scales. This is especially useful for cheaply generating large ensembles of accurate mock halo catalogs required to study galaxy clustering and weak lensing. The COLA method achieves its speed by calculating the large-scale dynamics exactly using LPT while letting the N-body code solve for the small scales, without requiring it to capture exactly the internal dynamics of halos.

  6. Identifying personal microbiomes using metagenomic codes.

    Science.gov (United States)

    Franzosa, Eric A; Huang, Katherine; Meadow, James F; Gevers, Dirk; Lemon, Katherine P; Bohannan, Brendan J M; Huttenhower, Curtis

    2015-06-02

    Community composition within the human microbiome varies across individuals, but it remains unknown if this variation is sufficient to uniquely identify individuals within large populations or stable enough to identify them over time. We investigated this by developing a hitting set-based coding algorithm and applying it to the Human Microbiome Project population. Our approach defined body site-specific metagenomic codes: sets of microbial taxa or genes prioritized to uniquely and stably identify individuals. Codes capturing strain variation in clade-specific marker genes were able to distinguish among 100s of individuals at an initial sampling time point. In comparisons with follow-up samples collected 30-300 d later, ∼30% of individuals could still be uniquely pinpointed using metagenomic codes from a typical body site; coincidental (false positive) matches were rare. Codes based on the gut microbiome were exceptionally stable and pinpointed >80% of individuals. The failure of a code to match its owner at a later time point was largely explained by the loss of specific microbial strains (at current limits of detection) and was only weakly associated with the length of the sampling interval. In addition to highlighting patterns of temporal variation in the ecology of the human microbiome, this work demonstrates the feasibility of microbiome-based identifiability-a result with important ethical implications for microbiome study design. The datasets and code used in this work are available for download from huttenhower.sph.harvard.edu/idability.

  7. Texture coding in the rat whisker system: slip-stick versus differential resonance.

    Directory of Open Access Journals (Sweden)

    Jason Wolfe

    2008-08-01

    Full Text Available Rats discriminate surface textures using their whiskers (vibrissae, but how whiskers extract texture information, and how this information is encoded by the brain, are not known. In the resonance model, whisker motion across different textures excites mechanical resonance in distinct subsets of whiskers, due to variation across whiskers in resonance frequency, which varies with whisker length. Texture information is therefore encoded by the spatial pattern of activated whiskers. In the competing kinetic signature model, different textures excite resonance equally across whiskers, and instead, texture is encoded by characteristic, nonuniform temporal patterns of whisker motion. We tested these models by measuring whisker motion in awake, behaving rats whisking in air and onto sandpaper surfaces. Resonant motion was prominent during whisking in air, with fundamental frequencies ranging from approximately 35 Hz for the long Delta whisker to approximately 110 Hz for the shorter D3 whisker. Resonant vibrations also occurred while whisking against textures, but the amplitude of resonance within single whiskers was independent of texture, contradicting the resonance model. Rather, whiskers resonated transiently during discrete, high-velocity, and high-acceleration slip-stick events, which occurred prominently during whisking on surfaces. The rate and magnitude of slip-stick events varied systematically with texture. These results suggest that texture is encoded not by differential resonant motion across whiskers, but by the magnitude and temporal pattern of slip-stick motion. These findings predict a temporal code for texture in neural spike trains.

  8. Epigenetic codes in cognition and behaviour.

    Science.gov (United States)

    Gräff, Johannes; Mansuy, Isabelle M

    2008-09-01

    The epigenetic marking of chromatin provides a ubiquitous means for cells to shape and maintain their identity, and to react to environmental stimuli via specific remodeling. Such an epigenetic code of the core components of chromatin, DNA and histone proteins, can thus be stable but is also highly dynamic. In the nervous system, epigenetic codes are critical for basic cellular processes such as synaptic plasticity, and for complex behaviours such as learning and memory. At the same time, epigenetic marks can be stably transmitted through mitosis and meiosis, and thereby underlie non-genomic transgenerational inheritance of behavioural traits. In this review, we describe recent findings on the role and mechanisms of epigenetic codes in the brain, and discuss their implication in synaptic plasticity, cognitive functions and psychiatric disorders. We provide examples of transgenerational inheritance of epigenetic marks that affect simple morphological traits or complex processes such as disease susceptibility, and point to the potential implication of epigenetic codes in medicine and evolution.

  9. Temporal plus epilepsy is a major determinant of temporal lobe surgery failures.

    Science.gov (United States)

    Barba, Carmen; Rheims, Sylvain; Minotti, Lorella; Guénot, Marc; Hoffmann, Dominique; Chabardès, Stephan; Isnard, Jean; Kahane, Philippe; Ryvlin, Philippe

    2016-02-01

    resection of temporal plus epileptogenic zones offers greater chance of seizure freedom remains to be investigated. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Semantics of Temporal Models with Multiple Temporal Dimensions

    DEFF Research Database (Denmark)

    Kraft, Peter; Sørensen, Jens Otto

    Semantics of temporal models with multi temporal dimensions are examined progressing from non-temporal models unto uni-temporal, and further unto bi- and tri-temporal models. An example of a uni-temporal model is the valid time model, an example of a bi-temporal model is the valid time/transactio...

  11. Coded continuous wave meteor radar

    Science.gov (United States)

    Chau, J. L.; Vierinen, J.; Pfeffer, N.; Clahsen, M.; Stober, G.

    2016-12-01

    The concept of a coded continuous wave specular meteor radar (SMR) is described. The radar uses a continuously transmitted pseudorandom phase-modulated waveform, which has several advantages compared to conventional pulsed SMRs. The coding avoids range and Doppler aliasing, which are in some cases problematic with pulsed radars. Continuous transmissions maximize pulse compression gain, allowing operation at lower peak power than a pulsed system. With continuous coding, the temporal and spectral resolution are not dependent on the transmit waveform and they can be fairly flexibly changed after performing a measurement. The low signal-to-noise ratio before pulse compression, combined with independent pseudorandom transmit waveforms, allows multiple geographically separated transmitters to be used in the same frequency band simultaneously without significantly interfering with each other. Because the same frequency band can be used by multiple transmitters, the same interferometric receiver antennas can be used to receive multiple transmitters at the same time. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large-scale multi-static network of meteor radar transmitters and receivers. Such a system would be useful for increasing the number of meteor detections to obtain improved meteor radar data products, such as wind fields. This type of a radar would also be useful for over-the-horizon radar, ionosondes, and observations of field-aligned-irregularities.

  12. The materiality of Code

    DEFF Research Database (Denmark)

    Soon, Winnie

    2014-01-01

    , Twitter and Facebook). The focus is not to investigate the functionalities and efficiencies of the code, but to study and interpret the program level of code in order to trace the use of various technological methods such as third-party libraries and platforms’ interfaces. These are important...... to understand the socio-technical side of a changing network environment. Through the study of code, including but not limited to source code, technical specifications and other materials in relation to the artwork production, I would like to explore the materiality of code that goes beyond technical...

  13. DLLExternalCode

    Energy Technology Data Exchange (ETDEWEB)

    2014-05-14

    DLLExternalCode is the a general dynamic-link library (DLL) interface for linking GoldSim (www.goldsim.com) with external codes. The overall concept is to use GoldSim as top level modeling software with interfaces to external codes for specific calculations. The DLLExternalCode DLL that performs the linking function is designed to take a list of code inputs from GoldSim, create an input file for the external application, run the external code, and return a list of outputs, read from files created by the external application, back to GoldSim. Instructions for creating the input file, running the external code, and reading the output are contained in an instructions file that is read and interpreted by the DLL.

  14. Noisy Network Coding

    CERN Document Server

    Lim, Sung Hoon; Gamal, Abbas El; Chung, Sae-Young

    2010-01-01

    A noisy network coding scheme for sending multiple sources over a general noisy network is presented. For multi-source multicast networks, the scheme naturally extends both network coding over noiseless networks by Ahlswede, Cai, Li, and Yeung, and compress-forward coding for the relay channel by Cover and El Gamal to general discrete memoryless and Gaussian networks. The scheme also recovers as special cases the results on coding for wireless relay networks and deterministic networks by Avestimehr, Diggavi, and Tse, and coding for wireless erasure networks by Dana, Gowaikar, Palanki, Hassibi, and Effros. The scheme involves message repetition coding, relay signal compression, and simultaneous decoding. Unlike previous compress--forward schemes, where independent messages are sent over multiple blocks, the same message is sent multiple times using independent codebooks as in the network coding scheme for cyclic networks. Furthermore, the relays do not use Wyner--Ziv binning as in previous compress-forward sch...

  15. Temporal compressive imaging for video

    Science.gov (United States)

    Zhou, Qun; Zhang, Linxia; Ke, Jun

    2018-01-01

    In many situations, imagers are required to have higher imaging speed, such as gunpowder blasting analysis and observing high-speed biology phenomena. However, measuring high-speed video is a challenge to camera design, especially, in infrared spectrum. In this paper, we reconstruct a high-frame-rate video from compressive video measurements using temporal compressive imaging (TCI) with a temporal compression ratio T=8. This means that, 8 unique high-speed temporal frames will be obtained from a single compressive frame using a reconstruction algorithm. Equivalently, the video frame rates is increased by 8 times. Two methods, two-step iterative shrinkage/threshold (TwIST) algorithm and the Gaussian mixture model (GMM) method, are used for reconstruction. To reduce reconstruction time and memory usage, each frame of size 256×256 is divided into patches of size 8×8. The influence of different coded mask to reconstruction is discussed. The reconstruction qualities using TwIST and GMM are also compared.

  16. Coding Strategies and Implementations of Compressive Sensing

    Science.gov (United States)

    Tsai, Tsung-Han

    This dissertation studies the coding strategies of computational imaging to overcome the limitation of conventional sensing techniques. The information capacity of conventional sensing is limited by the physical properties of optics, such as aperture size, detector pixels, quantum efficiency, and sampling rate. These parameters determine the spatial, depth, spectral, temporal, and polarization sensitivity of each imager. To increase sensitivity in any dimension can significantly compromise the others. This research implements various coding strategies subject to optical multidimensional imaging and acoustic sensing in order to extend their sensing abilities. The proposed coding strategies combine hardware modification and signal processing to exploiting bandwidth and sensitivity from conventional sensors. We discuss the hardware architecture, compression strategies, sensing process modeling, and reconstruction algorithm of each sensing system. Optical multidimensional imaging measures three or more dimensional information of the optical signal. Traditional multidimensional imagers acquire extra dimensional information at the cost of degrading temporal or spatial resolution. Compressive multidimensional imaging multiplexes the transverse spatial, spectral, temporal, and polarization information on a two-dimensional (2D) detector. The corresponding spectral, temporal and polarization coding strategies adapt optics, electronic devices, and designed modulation techniques for multiplex measurement. This computational imaging technique provides multispectral, temporal super-resolution, and polarization imaging abilities with minimal loss in spatial resolution and noise level while maintaining or gaining higher temporal resolution. The experimental results prove that the appropriate coding strategies may improve hundreds times more sensing capacity. Human auditory system has the astonishing ability in localizing, tracking, and filtering the selected sound sources or

  17. Analysis of Brain Recurrence

    Science.gov (United States)

    Frilot, Clifton; Kim, Paul Y.; Carrubba, Simona; McCarty, David E.; Chesson, Andrew L.; Marino, Andrew A.

    Analysis of Brain Recurrence (ABR) is a method for extracting physiologically significant information from the electroencephalogram (EEG), a non-stationary electrical output of the brain, the ultimate complex dynamical system. ABR permits quantification of temporal patterns in the EEG produced by the non-autonomous differential laws that govern brain metabolism. In the context of appropriate experimental and statistical designs, ABR is ideally suited to the task of interpreting the EEG. Present applications of ABR include discovery of a human magnetic sense, increased mechanistic understanding of neuronal membrane processes, diagnosis of degenerative neurological disease, detection of changes in brain metabolism caused by weak environmental electromagnetic fields, objective characterization of the quality of human sleep, and evaluation of sleep disorders. ABR has important beneficial implications for the development of clinical and experimental neuroscience.

  18. Standardization of Code on Dental Procedures

    Science.gov (United States)

    1992-02-13

    Steel. Aluminum, Tin, Composite.and/or Glass Ionomer. A crown used for short-term temporization or for pediatric dentistry treatment. Credit one per...provided as a management tool and should not be construed to represent the total practice of military dentistry . Category of Service Code Series 1...Class I. Occlusal surface restoration of molars and premolars, including buccal or occlusal pits, cast crown repairs, and small lingual surface

  19. An electrocorticographic BCI using code-based VEP for control in video applications: a single-subject study.

    Science.gov (United States)

    Kapeller, Christoph; Kamada, Kyousuke; Ogawa, Hiroshi; Prueckl, Robert; Scharinger, Josef; Guger, Christoph

    2014-01-01

    A brain-computer-interface (BCI) allows the user to control a device or software with brain activity. Many BCIs rely on visual stimuli with constant stimulation cycles that elicit steady-state visual evoked potentials (SSVEP) in the electroencephalogram (EEG). This EEG response can be generated with a LED or a computer screen flashing at a constant frequency, and similar EEG activity can be elicited with pseudo-random stimulation sequences on a screen (code-based BCI). Using electrocorticography (ECoG) instead of EEG promises higher spatial and temporal resolution and leads to more dominant evoked potentials due to visual stimulation. This work is focused on BCIs based on visual evoked potentials (VEP) and its capability as a continuous control interface for augmentation of video applications. One 35 year old female subject with implanted subdural grids participated in the study. The task was to select one out of four visual targets, while each was flickering with a code sequence. After a calibration run including 200 code sequences, a linear classifier was used during an evaluation run to identify the selected visual target based on the generated code-based VEPs over 20 trials. Multiple ECoG buffer lengths were tested and the subject reached a mean online classification accuracy of 99.21% for a window length of 3.15 s. Finally, the subject performed an unsupervised free run in combination with visual feedback of the current selection. Additionally, an algorithm was implemented that allowed to suppress false positive selections and this allowed the subject to start and stop the BCI at any time. The code-based BCI system attained very high online accuracy, which makes this approach very promising for control applications where a continuous control signal is needed.

  20. High baseline activity in inferior temporal cortex improves neural and behavioral discriminability during visual categorization

    Directory of Open Access Journals (Sweden)

    Nazli eEmadi

    2014-11-01

    Full Text Available Spontaneous firing is a ubiquitous property of neural activity in the brain. Recent literature suggests that this baseline activity plays a key role in perception. However, it is not known how the baseline activity contributes to neural coding and behavior. Here, by recording from the single neurons in the inferior temporal cortex of monkeys performing a visual categorization task, we thoroughly explored the relationship between baseline activity, the evoked response, and behavior. Specifically we found that a low-frequency (< 8 Hz oscillation in the spike train, prior and phase-locked to the stimulus onset, was correlated with increased gamma power and neuronal baseline activity. This enhancement of the baseline activity was then followed by an increase in the neural selectivity and the response reliability and eventually a higher behavioral performance.

  1. The Aesthetics of Coding

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik

    2007-01-01

    Computer art is often associated with computer-generated expressions (digitally manipulated audio/images in music, video, stage design, media facades, etc.). In recent computer art, however, the code-text itself – not the generated output – has become the artwork (Perl Poetry, ASCII Art, obfuscated...... code, etc.). The presentation relates this artistic fascination of code to a media critique expressed by Florian Cramer, claiming that the graphical interface represents a media separation (of text/code and image) causing alienation to the computer’s materiality. Cramer is thus the voice of a new ‘code...... avant-garde’. In line with Cramer, the artists Alex McLean and Adrian Ward (aka Slub) declare: “art-oriented programming needs to acknowledge the conditions of its own making – its poesis.” By analysing the Live Coding performances of Slub (where they program computer music live), the presentation...

  2. Opening up codings?

    DEFF Research Database (Denmark)

    Steensig, Jakob; Heinemann, Trine

    2015-01-01

    doing formal coding and when doing more “traditional” conversation analysis research based on collections. We are more wary, however, of the implication that coding-based research is the end result of a process that starts with qualitative investigations and ends with categories that can be coded......We welcome Tanya Stivers’s discussion (Stivers, 2015/this issue) of coding social interaction and find that her descriptions of the processes of coding open up important avenues for discussion, among other things of the precise ad hoc considerations that researchers need to bear in mind, both when....... Instead we propose that the promise of coding-based research lies in its ability to open up new qualitative questions....

  3. Overview of Code Verification

    Science.gov (United States)

    1983-01-01

    The verified code for the SIFT Executive is not the code that executes on the SIFT system as delivered. The running versions of the SIFT Executive contain optimizations and special code relating to the messy interface to the hardware broadcast interface and to packing of data to conserve space in the store of the BDX930 processors. The running code was in fact developed prior to and without consideration of any mechanical verification. This was regarded as necessary experimentation with the SIFT hardware and special purpose Pascal compiler. The Pascal code sections cover: the selection of a schedule from the global executive broadcast, scheduling, dispatching, three way voting, and error reporting actions of the SIFT Executive. Not included in these sections of Pascal code are: the global executive, five way voting, clock synchronization, interactive consistency, low level broadcasting, and program loading, initialization, and schedule construction.

  4. Brain Tumors

    Science.gov (United States)

    A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, ... cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are ...

  5. Brain Basics

    Medline Plus

    Full Text Available ... Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video Welcome. Brain Basics ... basic, working unit of the brain and nervous system, which processes and transmits information. neurotransmitter —A chemical produced by neurons that carries ...

  6. Brain Basics

    Medline Plus

    Full Text Available ... learning more about how the brain grows and works in healthy people, and how normal brain development and function can go awry, leading to mental illnesses. Brain Basics will introduce you to some of this science, such as: ... of the brain communicate and work with each other How changes in the brain ...

  7. Phonological coding during reading

    Science.gov (United States)

    Leinenger, Mallorie

    2014-01-01

    The exact role that phonological coding (the recoding of written, orthographic information into a sound based code) plays during silent reading has been extensively studied for more than a century. Despite the large body of research surrounding the topic, varying theories as to the time course and function of this recoding still exist. The present review synthesizes this body of research, addressing the topics of time course and function in tandem. The varying theories surrounding the function of phonological coding (e.g., that phonological codes aid lexical access, that phonological codes aid comprehension and bolster short-term memory, or that phonological codes are largely epiphenomenal in skilled readers) are first outlined, and the time courses that each maps onto (e.g., that phonological codes come online early (pre-lexical) or that phonological codes come online late (post-lexical)) are discussed. Next the research relevant to each of these proposed functions is reviewed, discussing the varying methodologies that have been used to investigate phonological coding (e.g., response time methods, reading while eyetracking or recording EEG and MEG, concurrent articulation) and highlighting the advantages and limitations of each with respect to the study of phonological coding. In response to the view that phonological coding is largely epiphenomenal in skilled readers, research on the use of phonological codes in prelingually, profoundly deaf readers is reviewed. Finally, implications for current models of word identification (activation-verification model (Van Order, 1987), dual-route model (e.g., Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001), parallel distributed processing model (Seidenberg & McClelland, 1989)) are discussed. PMID:25150679

  8. The aeroelastic code FLEXLAST

    Energy Technology Data Exchange (ETDEWEB)

    Visser, B. [Stork Product Eng., Amsterdam (Netherlands)

    1996-09-01

    To support the discussion on aeroelastic codes, a description of the code FLEXLAST was given and experiences within benchmarks and measurement programmes were summarized. The code FLEXLAST has been developed since 1982 at Stork Product Engineering (SPE). Since 1992 FLEXLAST has been used by Dutch industries for wind turbine and rotor design. Based on the comparison with measurements, it can be concluded that the main shortcomings of wind turbine modelling lie in the field of aerodynamics, wind field and wake modelling. (au)

  9. Generating code adapted for interlinking legacy scalar code and extended vector code

    Science.gov (United States)

    Gschwind, Michael K

    2013-06-04

    Mechanisms for intermixing code are provided. Source code is received for compilation using an extended Application Binary Interface (ABI) that extends a legacy ABI and uses a different register configuration than the legacy ABI. First compiled code is generated based on the source code, the first compiled code comprising code for accommodating the difference in register configurations used by the extended ABI and the legacy ABI. The first compiled code and second compiled code are intermixed to generate intermixed code, the second compiled code being compiled code that uses the legacy ABI. The intermixed code comprises at least one call instruction that is one of a call from the first compiled code to the second compiled code or a call from the second compiled code to the first compiled code. The code for accommodating the difference in register configurations is associated with the at least one call instruction.

  10. Decoding of Cyclic Codes,

    Science.gov (United States)

    INFORMATION THEORY, *DECODING), (* DATA TRANSMISSION SYSTEMS , DECODING), STATISTICAL ANALYSIS, STOCHASTIC PROCESSES, CODING, WHITE NOISE, NUMBER THEORY, CORRECTIONS, BINARY ARITHMETIC, SHIFT REGISTERS, CONTROL SYSTEMS, USSR

  11. ARC Code TI: ACCEPT

    Data.gov (United States)

    National Aeronautics and Space Administration — ACCEPT consists of an overall software infrastructure framework and two main software components. The software infrastructure framework consists of code written to...

  12. Diameter Perfect Lee Codes

    CERN Document Server

    Horak, Peter

    2011-01-01

    Lee codes have been intensively studied for more than 40 years. Interest in these codes has been triggered by the Golomb-Welch conjecture on the existence of perfect error-correcting Lee codes. In this paper we deal with the existence and enumeration of diameter perfect Lee codes. As main results we determine all q for which there exists a linear diameter-4 perfect Lee code of word length n over Z_{q}, and prove that for each n\\geq3 there are unaccountably many diameter-4 perfect Lee codes of word length n over Z. This is in a strict contrast with perfect error-correcting Lee codes of word length n over Z as there is a unique such code for n=3, and its is conjectured that this is always the case when 2n+1 is a prime. Diameter perfect Lee codes will be constructed by an algebraic construction that is based on a group homomorphism. This will allow us to design an efficient algorithm for their decoding.

  13. Expander chunked codes

    Science.gov (United States)

    Tang, Bin; Yang, Shenghao; Ye, Baoliu; Yin, Yitong; Lu, Sanglu

    2015-12-01

    Chunked codes are efficient random linear network coding (RLNC) schemes with low computational cost, where the input packets are encoded into small chunks (i.e., subsets of the coded packets). During the network transmission, RLNC is performed within each chunk. In this paper, we first introduce a simple transfer matrix model to characterize the transmission of chunks and derive some basic properties of the model to facilitate the performance analysis. We then focus on the design of overlapped chunked codes, a class of chunked codes whose chunks are non-disjoint subsets of input packets, which are of special interest since they can be encoded with negligible computational cost and in a causal fashion. We propose expander chunked (EC) codes, the first class of overlapped chunked codes that have an analyzable performance, where the construction of the chunks makes use of regular graphs. Numerical and simulation results show that in some practical settings, EC codes can achieve rates within 91 to 97 % of the optimum and outperform the state-of-the-art overlapped chunked codes significantly.

  14. QR codes for dummies

    CERN Document Server

    Waters, Joe

    2012-01-01

    Find out how to effectively create, use, and track QR codes QR (Quick Response) codes are popping up everywhere, and businesses are reaping the rewards. Get in on the action with the no-nonsense advice in this streamlined, portable guide. You'll find out how to get started, plan your strategy, and actually create the codes. Then you'll learn to link codes to mobile-friendly content, track your results, and develop ways to give your customers value that will keep them coming back. It's all presented in the straightforward style you've come to know and love, with a dash of humor thrown

  15. On {\\sigma}-LCD codes

    OpenAIRE

    Carlet, Claude; Mesnager, Sihem; Tang, Chunming; Qi, Yanfeng

    2017-01-01

    Linear complementary pairs (LCP) of codes play an important role in armoring implementations against side-channel attacks and fault injection attacks. One of the most common ways to construct LCP of codes is to use Euclidean linear complementary dual (LCD) codes. In this paper, we first introduce the concept of linear codes with $\\sigma$ complementary dual ($\\sigma$-LCD), which includes known Euclidean LCD codes, Hermitian LCD codes, and Galois LCD codes. As Euclidean LCD codes, $\\sigma$-LCD ...

  16. Brain Malformations

    Science.gov (United States)

    Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections, or radiation during pregnancy interferes with brain development. Parts of the brain may be missing, ...

  17. Brain surgery

    Science.gov (United States)

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  18. Brain Basics

    Medline Plus

    Full Text Available ... Real Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a ... brain. DNA —The "recipe of life," containing inherited genetic information that helps to define physical and some ...

  19. Brain Basics

    Medline Plus

    Full Text Available ... brain's structure, studies show that brain growth in children with autism appears to peak early. And as ... grow there are differences in brain development in children who develop bipolar disorder than children who do ...

  20. Brain Basics

    Medline Plus

    Full Text Available ... brain's structure, studies show that brain growth in children with autism appears to peak early. And as they grow there are differences in brain development in children who develop bipolar disorder than children ...

  1. Brain Basics

    Medline Plus

    Full Text Available ... imaging (MRI), which uses magnetic fields to take pictures of the brain's structure, studies show that brain ... imaging technique that uses magnetic fields to take pictures of the brain's structure. mutation —A change in ...

  2. Brain Basics

    Medline Plus

    Full Text Available ... as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits Neurons are the basic working unit of the brain ... specialized for the function of conducting messages. A neuron has three basic parts: Cell body which includes ...

  3. Brain Basics

    Medline Plus

    Full Text Available ... of the brain's structure, studies show that brain growth in children with autism appears to peak early. And as they grow there are differences in brain development in children who develop bipolar disorder than children ...

  4. Brain Basics

    Medline Plus

    Full Text Available ... science, such as: How the brain develops How genes and the environment affect the brain The basic ... that with brain development in people mental disorders. Genes and environmental cues both help to direct this ...

  5. Brain Basics

    Medline Plus

    Full Text Available ... the Brain Meet Sarah Sarah is a middle-aged woman who seemed to have it all. She ... brain's structure, studies show that brain growth in children with autism appears to peak early. And as ...

  6. Brain Basics

    Medline Plus

    Full Text Available ... about how the brain grows and works in healthy people, and how normal brain development and function ... chart how the brain develops over time in healthy people and are working to compare that with ...

  7. Brain Basics

    Medline Plus

    Full Text Available ... Life Brain Basics in Real Life—How Depression affects the Brain Meet Sarah Sarah is a middle- ... unit of the brain and nervous system, which processes and transmits information. neurotransmitter —A chemical produced by ...

  8. Brain Basics

    Medline Plus

    Full Text Available ... Mental Illnesses Clinical Trials Outreach Outreach Home Stakeholder Engagement Outreach Partnership Program Alliance for Research Progress Coalition ... Brain Basics provides information on how the brain works, how mental illnesses are disorders of the brain, ...

  9. Brain Basics

    Medline Plus

    Full Text Available ... in Real Life Brain Research Glossary Brain Basics (PDF, 10 pages) Introduction Watch the Brain Basics video ... and epigenetic changes can be passed on to future generations. Further understanding of genes and epigenetics may ...

  10. Brain Basics

    Medline Plus

    Full Text Available ... can lead to mental disorders, such as depression. The Growing Brain Inside the Brain: Neurons & Neural Circuits ... tailored treatments, and possibly prevention of such illnesses. The Working Brain Neurotransmitters Everything we do relies on ...

  11. Temporal logic runtime verification of dynamic systems

    CSIR Research Space (South Africa)

    Seotsanyana, M

    2010-07-01

    Full Text Available linear temporal logic as well as extended regular expressions. Java with assertion (Jass) [8] is a general monitoring methodology implemented for sequential, concurrent and reactive systems written in java. The tool Jass is a pre- compiler... that translates annotations into a pure java code in which a compliance with specification is tested dynamically at runtime. Assertions extends the Design by Contract [11], that allows specification of assertions in the form of pre- and post-conditions, class...

  12. Scrum Code Camps

    DEFF Research Database (Denmark)

    Pries-Heje, Jan; Pries-Heje, Lene; Dahlgaard, Bente

    2013-01-01

    is required. In this paper we present the design of such a new approach, the Scrum Code Camp, which can be used to assess agile team capability in a transparent and consistent way. A design science research approach is used to analyze properties of two instances of the Scrum Code Camp where seven agile teams...

  13. Error Correcting Codes

    Indian Academy of Sciences (India)

    be fixed to define codes over such domains). New decoding schemes that take advantage of such connections can be devised. These may soon show up in a technique called code division multiple access (CDMA) which is proposed as a basis for digital cellular communication. CDMA provides a facility for many users to ...

  14. Codes of Conduct

    Science.gov (United States)

    Million, June

    2004-01-01

    Most schools have a code of conduct, pledge, or behavioral standards, set by the district or school board with the school community. In this article, the author features some schools that created a new vision of instilling code of conducts to students based on work quality, respect, safety and courtesy. She suggests that communicating the code…

  15. Error Correcting Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 3. Error Correcting Codes - Reed Solomon Codes. Priti Shankar. Series Article Volume 2 Issue 3 March 1997 pp 33-47. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/03/0033-0047 ...

  16. Code Generation = A* + BURS

    NARCIS (Netherlands)

    Nymeyer, Albert; Katoen, Joost P.; Westra, Ymte; Alblas, H.; Gyimóthy, Tibor

    1996-01-01

    A system called BURS that is based on term rewrite systems and a search algorithm A* are combined to produce a code generator that generates optimal code. The theory underlying BURS is re-developed, formalised and explained in this work. The search algorithm uses a cost heuristic that is derived

  17. Dress Codes for Teachers?

    Science.gov (United States)

    Million, June

    2004-01-01

    In this article, the author discusses an e-mail survey of principals from across the country regarding whether or not their school had a formal staff dress code. The results indicate that most did not have a formal dress code, but agreed that professional dress for teachers was not only necessary, but showed respect for the school and had a…

  18. Informal control code logic

    NARCIS (Netherlands)

    Bergstra, J.A.

    2010-01-01

    General definitions as well as rules of reasoning regarding control code production, distribution, deployment, and usage are described. The role of testing, trust, confidence and risk analysis is considered. A rationale for control code testing is sought and found for the case of safety critical

  19. Interleaved Product LDPC Codes

    OpenAIRE

    Baldi, Marco; Cancellieri, Giovanni; Chiaraluce, Franco

    2011-01-01

    Product LDPC codes take advantage of LDPC decoding algorithms and the high minimum distance of product codes. We propose to add suitable interleavers to improve the waterfall performance of LDPC decoding. Interleaving also reduces the number of low weight codewords, that gives a further advantage in the error floor region.

  20. Nuremberg code turns 60

    OpenAIRE

    Thieren, Michel; Mauron, Alexandre

    2007-01-01

    This month marks sixty years since the Nuremberg code – the basic text of modern medical ethics – was issued. The principles in this code were articulated in the context of the Nuremberg trials in 1947. We would like to use this anniversary to examine its ability to address the ethical challenges of our time.

  1. Error Correcting Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 1. Error Correcting Codes The Hamming Codes. Priti Shankar. Series Article Volume 2 Issue 1 January ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India ...

  2. Coding stimulus amplitude by correlated neural activity.

    Science.gov (United States)

    Metzen, Michael G; Ávila-Åkerberg, Oscar; Chacron, Maurice J

    2015-04-01

    While correlated activity is observed ubiquitously in the brain, its role in neural coding has remained controversial. Recent experimental results have demonstrated that correlated but not single-neuron activity can encode the detailed time course of the instantaneous amplitude (i.e., envelope) of a stimulus. These have furthermore demonstrated that such coding required and was optimal for a nonzero level of neural variability. However, a theoretical understanding of these results is still lacking. Here we provide a comprehensive theoretical framework explaining these experimental findings. Specifically, we use linear response theory to derive an expression relating the correlation coefficient to the instantaneous stimulus amplitude, which takes into account key single-neuron properties such as firing rate and variability as quantified by the coefficient of variation. The theoretical prediction was in excellent agreement with numerical simulations of various integrate-and-fire type neuron models for various parameter values. Further, we demonstrate a form of stochastic resonance as optimal coding of stimulus variance by correlated activity occurs for a nonzero value of noise intensity. Thus, our results provide a theoretical explanation of the phenomenon by which correlated but not single-neuron activity can code for stimulus amplitude and how key single-neuron properties such as firing rate and variability influence such coding. Correlation coding by correlated but not single-neuron activity is thus predicted to be a ubiquitous feature of sensory processing for neurons responding to weak input.

  3. Temporal Processing in Audition: Insights from Music.

    Science.gov (United States)

    Rajendran, Vani G; Teki, Sundeep; Schnupp, Jan W H

    2017-11-03

    Music is a curious example of a temporally patterned acoustic stimulus, and a compelling pan-cultural phenomenon. This review strives to bring some insights from decades of music psychology and sensorimotor synchronization (SMS) literature into the mainstream auditory domain, arguing that musical rhythm perception is shaped in important ways by temporal processing mechanisms in the brain. The feature that unites these disparate disciplines is an appreciation of the central importance of timing, sequencing, and anticipation. Perception of musical rhythms relies on an ability to form temporal predictions, a general feature of temporal processing that is equally relevant to auditory scene analysis, pattern detection, and speech perception. By bringing together findings from the music and auditory literature, we hope to inspire researchers to look beyond the conventions of their respective fields and consider the cross-disciplinary implications of studying auditory temporal sequence processing. We begin by highlighting music as an interesting sound stimulus that may provide clues to how temporal patterning in sound drives perception. Next, we review the SMS literature and discuss possible neural substrates for the perception of, and synchronization to, musical beat. We then move away from music to explore the perceptual effects of rhythmic timing in pattern detection, auditory scene analysis, and speech perception. Finally, we review the neurophysiology of general timing processes that may underlie aspects of the perception of rhythmic patterns. We conclude with a brief summary and outlook for future research. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. The α1, α2, α3, and γ2 subunits of GABAA receptors show characteristic spatial and temporal expression patterns in rhombencephalic structures during normal human brain development.

    Science.gov (United States)

    Stojanovic, Tamara; Capo, Ivan; Aronica, Eleonora; Adle-Biassette, Homa; Höger, Harald; Sieghart, Werner; Kovacs, Gabor G; Milenkovic, Ivan

    2016-06-15

    γ-Aminobutyric acid (GABA) is the most abundant inhibitory neurotransmitter in adult mammalian brain, mediating its actions chiefly via a pentameric chloride ion channel, the GABAA receptor. Nineteen different subunits (α1-6, β1-3, γ1-3, δ, ε, π, θ, ρ1-3) can give rise to multiple receptor subtypes that are the site of action of many clinically important drugs. In the developing brain, however, GABAA receptors mediate excitatory actions due to an increased chloride concentration within neurons and seem to control cell proliferation, migration, differentiation, synapse maturation, and cell death. Little is known about the distribution of single subunits in the human brain. Here we describe developmental changes in the immunohistochemical distribution of four subunits (α1, α2, α3, and γ2) in the human rhombencephalon. The γ2 was the most abundant subunit in all rhombencephalic structures during development and in adults, whereas α subunits showed a structure- and age-characteristic distribution. The α1 was expressed prenatally in the molecular and Purkinje cell layer, but only postnatally in the granule cell layer and the dentate nucleus. Expression was completely absent in the inferior olivary nucleus. The α2 gradually increased during development, showing some layer specificity in the cerebellar cortex. The α3-immunoreactivity in the cerebellar cortex was relatively weak, but it was abundantly observed in different cell populations in the subcortical cerebellar structures. Structure- and age-characteristic colocalization between subunits during development suggests differences in GABAA receptor composition. Interestingly, subunit expression in several instances differed between human and rodent brain, underlining the importance of immunohistochemical studies in humans. © 2015 Wiley Periodicals, Inc.

  5. Inductive Temporal Logic Programming

    OpenAIRE

    Kolter, Robert

    2009-01-01

    We study the extension of techniques from Inductive Logic Programming (ILP) to temporal logic programming languages. Therefore we present two temporal logic programming languages and analyse the learnability of programs from these languages from finite sets of examples. In first order temporal logic the following topics are analysed: - How can we characterize the denotational semantics of programs? - Which proof techniques are best suited? - How complex is the learning task? In propositional ...

  6. Evaluation Codes from an Affine Veriety Code Perspective

    DEFF Research Database (Denmark)

    Geil, Hans Olav

    2008-01-01

    Evaluation codes (also called order domain codes) are traditionally introduced as generalized one-point geometric Goppa codes. In the present paper we will give a new point of view on evaluation codes by introducing them instead as particular nice examples of affine variety codes. Our study...... . . . . . . . . . . . . . . . . . . . . . . . 171 4.9 Codes form order domains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 4.10 One-point geometric Goppa codes . . . . . . . . . . . . . . . . . . . . . . . . 176 4.11 Bibliographical Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 References...

  7. Quantum Synchronizable Codes From Quadratic Residue Codes and Their Supercodes

    OpenAIRE

    Xie, Yixuan; Yuan, Jinhong; Fujiwara, Yuichiro

    2014-01-01

    Quantum synchronizable codes are quantum error-correcting codes designed to correct the effects of both quantum noise and block synchronization errors. While it is known that quantum synchronizable codes can be constructed from cyclic codes that satisfy special properties, only a few classes of cyclic codes have been proved to give promising quantum synchronizable codes. In this paper, using quadratic residue codes and their supercodes, we give a simple construction for quantum synchronizable...

  8. Olfactory coding in the turbulent realm.

    Directory of Open Access Journals (Sweden)

    Vincent Jacob

    2017-12-01

    Full Text Available Long-distance olfactory search behaviors depend on odor detection dynamics. Due to turbulence, olfactory signals travel as bursts of variable concentration and spacing and are characterized by long-tail distributions of odor/no-odor events, challenging the computing capacities of olfactory systems. How animals encode complex olfactory scenes to track the plume far from the source remains unclear. Here we focus on the coding of the plume temporal dynamics in moths. We compare responses of olfactory receptor neurons (ORNs and antennal lobe projection neurons (PNs to sequences of pheromone stimuli either with white-noise patterns or with realistic turbulent temporal structures simulating a large range of distances (8 to 64 m from the odor source. For the first time, we analyze what information is extracted by the olfactory system at large distances from the source. Neuronal responses are analyzed using linear-nonlinear models fitted with white-noise stimuli and used for predicting responses to turbulent stimuli. We found that neuronal firing rate is less correlated with the dynamic odor time course when distance to the source increases because of improper coding during long odor and no-odor events that characterize large distances. Rapid adaptation during long puffs does not preclude however the detection of puff transitions in PNs. Individual PNs but not individual ORNs encode the onset and offset of odor puffs for any temporal structure of stimuli. A higher spontaneous firing rate coupled to an inhibition phase at the end of PN responses contributes to this coding property. This allows PNs to decode the temporal structure of the odor plume at any distance to the source, an essential piece of information moths can use in their tracking behavior.

  9. Olfactory coding in the turbulent realm.

    Science.gov (United States)

    Jacob, Vincent; Monsempès, Christelle; Rospars, Jean-Pierre; Masson, Jean-Baptiste; Lucas, Philippe

    2017-12-01

    Long-distance olfactory search behaviors depend on odor detection dynamics. Due to turbulence, olfactory signals travel as bursts of variable concentration and spacing and are characterized by long-tail distributions of odor/no-odor events, challenging the computing capacities of olfactory systems. How animals encode complex olfactory scenes to track the plume far from the source remains unclear. Here we focus on the coding of the plume temporal dynamics in moths. We compare responses of olfactory receptor neurons (ORNs) and antennal lobe projection neurons (PNs) to sequences of pheromone stimuli either with white-noise patterns or with realistic turbulent temporal structures simulating a large range of distances (8 to 64 m) from the odor source. For the first time, we analyze what information is extracted by the olfactory system at large distances from the source. Neuronal responses are analyzed using linear-nonlinear models fitted with white-noise stimuli and used for predicting responses to turbulent stimuli. We found that neuronal firing rate is less correlated with the dynamic odor time course when distance to the source increases because of improper coding during long odor and no-odor events that characterize large distances. Rapid adaptation during long puffs does not preclude however the detection of puff transitions in PNs. Individual PNs but not individual ORNs encode the onset and offset of odor puffs for any temporal structure of stimuli. A higher spontaneous firing rate coupled to an inhibition phase at the end of PN responses contributes to this coding property. This allows PNs to decode the temporal structure of the odor plume at any distance to the source, an essential piece of information moths can use in their tracking behavior.

  10. Optimizing memory function in temporal lobe epilepsy

    OpenAIRE

    Thompson, P.J.; Conn, H.; Baxendale, S. A.; Donnachie, E.; McGrath, K.; Geraldi, C.; Duncan, J.S.

    2016-01-01

    PURPOSE: The study aimed to assess whether engagement in a memory training programme and performing internet brain training exercises improve memory function in people with temporal lobe epilepsy (TLE). METHODS: Seventy-seven people with TLE, complaining of memory difficulties, completed the study. Participants ranged in age from 19 to 67 years and 40 had left TLE. Participants were randomised to one of four conditions; Group 1: traditional memory training, Group 2: Lumosity, an on-line cogni...

  11. Indeterministic Temporal Logic

    Directory of Open Access Journals (Sweden)

    Trzęsicki Kazimierz

    2015-09-01

    Full Text Available The questions od determinism, causality, and freedom have been the main philosophical problems debated since the beginning of temporal logic. The issue of the logical value of sentences about the future was stated by Aristotle in the famous tomorrow sea-battle passage. The question has inspired Łukasiewicz’s idea of many-valued logics and was a motive of A. N. Prior’s considerations about the logic of tenses. In the scheme of temporal logic there are different solutions to the problem. In the paper we consider indeterministic temporal logic based on the idea of temporal worlds and the relation of accessibility between them.

  12. Dynamic perfusion patterns in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Dupont, Patrick; Paesschen, Wim van [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); Zaknun, John J. [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); University Hospital of Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Maes, Alex [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); AZ Groeninge, Nuclear Medicine, Kortrijk (Belgium); Tepmongkol, Supatporn; Locharernkul, Chaichon [Chulalongkorn University, Nuclear Medicine and Neurology, Bangkok (Thailand); Vasquez, Silvia; Carpintiero, Silvina [Fleni Instituto de Investigaciones Neurologicas, Nuclear Medicine, Buenos Aires (Argentina); Bal, C.S. [All India Institute of Medical Sciences, Nuclear Medicine, New Delhi (India); Dondi, Maurizio [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); Ospedale Maggiore, Nuclear Medicine, Bologna (Italy)

    2009-05-15

    To investigate dynamic ictal perfusion changes during temporal lobe epilepsy (TLE). We investigated 37 patients with TLE by ictal and interictal SPECT. All ictal injections were performed within 60 s of seizure onset. Statistical parametric mapping was used to analyse brain perfusion changes and temporal relationships with injection time and seizure duration as covariates. The analysis revealed significant ictal hyperperfusion in the ipsilateral temporal lobe extending to subcortical regions. Hypoperfusion was observed in large extratemporal areas. There were also significant dynamic changes in several extratemporal regions: ipsilateral orbitofrontal and bilateral superior frontal gyri and the contralateral cerebellum and ipsilateral striatum. The study demonstrated early dynamic perfusion changes in extratemporal regions probably involved in both propagation of epileptic activity and initiation of inhibitory mechanisms. (orig.)

  13. Epilepsia do lobo temporal: mecanismos e perspectivas

    Directory of Open Access Journals (Sweden)

    Maria José da Silva Fernandes

    2013-01-01

    Full Text Available O artigo apresenta uma breve revisão sobre os achados históricos, epidemiológicos, tratamento e perspectivas terapêuticas para as epilepsias, com enfoque na epilepsia do lobo temporal. Apresenta dados obtidos com estudos de proteômica empregando tecido epiléptico e destaca a importância da aplicação desse método na busca de novos alvos terapêuticos.The article presents a brief review of the historical findings, epidemiological, and therapeutic treatment for epilepsy, with a focus on temporal lobe epilepsy. Presents data from proteomic studies in epileptic brain tissue and highlights the importance of the application of this method in the search for new therapeutic targets for temporal lobe epilepsy.

  14. Coding in the mammalian gustatory system.

    Science.gov (United States)

    Carleton, Alan; Accolla, Riccardo; Simon, Sidney A

    2010-07-01

    To understand gustatory physiology and associated dysfunctions it is important to know how oral taste stimuli are encoded both in the periphery and in taste-related brain centres. The identification of distinct taste receptors, together with electrophysiological recordings and behavioral assessments in response to taste stimuli, suggest that information about distinct taste modalities (e.g. sweet versus bitter) are transmitted from the periphery to the brain via segregated pathways. By contrast, gustatory neurons throughout the brain are more broadly tuned, indicating that ensembles of neurons encode taste qualities. Recent evidence reviewed here suggests that the coding of gustatory stimuli is not immutable, but is dependant on a variety of factors including appetite-regulating molecules and associative learning. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  15. Pyramid image codes

    Science.gov (United States)

    Watson, Andrew B.

    1990-01-01

    All vision systems, both human and machine, transform the spatial image into a coded representation. Particular codes may be optimized for efficiency or to extract useful image features. Researchers explored image codes based on primary visual cortex in man and other primates. Understanding these codes will advance the art in image coding, autonomous vision, and computational human factors. In cortex, imagery is coded by features that vary in size, orientation, and position. Researchers have devised a mathematical model of this transformation, called the Hexagonal oriented Orthogonal quadrature Pyramid (HOP). In a pyramid code, features are segregated by size into layers, with fewer features in the layers devoted to large features. Pyramid schemes provide scale invariance, and are useful for coarse-to-fine searching and for progressive transmission of images. The HOP Pyramid is novel in three respects: (1) it uses a hexagonal pixel lattice, (2) it uses oriented features, and (3) it accurately models most of the prominent aspects of primary visual cortex. The transform uses seven basic features (kernels), which may be regarded as three oriented edges, three oriented bars, and one non-oriented blob. Application of these kernels to non-overlapping seven-pixel neighborhoods yields six oriented, high-pass pyramid layers, and one low-pass (blob) layer.

  16. Report number codes

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.N. (ed.)

    1985-05-01

    This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

  17. Brain imaging and autism

    Energy Technology Data Exchange (ETDEWEB)

    Zilbovicius, M. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), INSERM CEA 0205, 91 - Orsay (France)

    2006-07-01

    Autism is a neuro-developmental disorder with a range of clinical presentations, from mild to severe, referred to as autism spectrum disorders (ASD). The most common clinical ASD sign is social interaction impairment, which is associated with verbal and non-verbal communication deficits and stereotyped and obsessive behaviors. Thanks to recent brain imaging studies, scientists are getting a better idea of the neural circuits involved in ASD. Indeed, functional brain imaging, such as positron emission tomography (PET), single positron emission tomograph y (SPECT) and functional MRI (fMRI) have opened a new perspective to study normal and pathological brain functions. Three independent studies have found anatomical and rest functional temporal abnormalities. These anomalies are localized in the superior temporal sulcus bilaterally which are critical for perception of key social stimuli. In addition, functional studies have shown hypo-activation of most areas implicated in social perception (face and voice perception) and social cognition (theory of mind). These data suggest an abnormal functioning of the social brain network. The understanding of such crucial abnormal mechanism may drive the elaboration of new and more adequate social re-educative strategies in autism. (author)

  18. Topodynamics of metastable brains

    Science.gov (United States)

    Tozzi, Arturo; Peters, James F.; Fingelkurts, Andrew A.; Fingelkurts, Alexander A.; Marijuán, Pedro C.

    2017-07-01

    The brain displays both the anatomical features of a vast amount of interconnected topological mappings as well as the functional features of a nonlinear, metastable system at the edge of chaos, equipped with a phase space where mental random walks tend towards lower energetic basins. Nevertheless, with the exception of some advanced neuro-anatomic descriptions and present-day connectomic research, very few studies have been addressing the topological path of a brain embedded or embodied in its external and internal environment. Herein, by using new formal tools derived from algebraic topology, we provide an account of the metastable brain, based on the neuro-scientific model of Operational Architectonics of brain-mind functioning. We introduce a ;topodynamic; description that shows how the relationships among the countless intertwined spatio-temporal levels of brain functioning can be assessed in terms of projections and mappings that take place on abstract structures, equipped with different dimensions, curvatures and energetic constraints. Such a topodynamical approach, apart from providing a biologically plausible model of brain function that can be operationalized, is also able to tackle the issue of a long-standing dichotomy: it throws indeed a bridge between the subjective, immediate datum of the naïve complex of sensations and mentations and the objective, quantitative, data extracted from experimental neuro-scientific procedures. Importantly, it opens the door to a series of new predictions and future directions of advancement for neuroscientific research.

  19. Cryptography cracking codes

    CERN Document Server

    2014-01-01

    While cracking a code might seem like something few of us would encounter in our daily lives, it is actually far more prevalent than we may realize. Anyone who has had personal information taken because of a hacked email account can understand the need for cryptography and the importance of encryption-essentially the need to code information to keep it safe. This detailed volume examines the logic and science behind various ciphers, their real world uses, how codes can be broken, and the use of technology in this oft-overlooked field.

  20. Quantum coding theorems

    Science.gov (United States)

    Holevo, A. S.

    1998-12-01

    ContentsI. IntroductionII. General considerations § 1. Quantum communication channel § 2. Entropy bound and channel capacity § 3. Formulation of the quantum coding theorem. Weak conversionIII. Proof of the direct statement of the coding theorem § 1. Channels with pure signal states § 2. Reliability function § 3. Quantum binary channel § 4. Case of arbitrary states with bounded entropyIV. c-q channels with input constraints § 1. Coding theorem § 2. Gauss channel with one degree of freedom § 3. Classical signal on quantum background noise Bibliography