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Author Awasthi, B.; Sowman, P.F.; Friedman, J.; Williams, M.A. pdf  url
doi  openurl
  Title Distinct spatial scale sensitivities for early categorisation of Faces and Places: Neuromagnetic and Behavioural Findings Type Journal Article
  Year 2013 Publication Frontiers in Human Neuroscience Abbreviated Journal  
  Volume 7 Issue 91 Pages  
  Keywords  
  Abstract (up) Research exploring the role of spatial frequencies in rapid stimulus detection and categorisation report flexible reliance on specific spatial frequency bands. Here, through a set of behavioural and magnetoencephalography (MEG) experiments, we investigated the role of low spatial frequency (LSF)(25 cpf) information during the categorisation of faces and places. Reaction time measures revealed significantly faster categorisation of faces driven by LSF information, while rapid categorisation of places was facilitated by HSF information. The MEG study showed significantly earlier latency of the M170 component for LSF faces compared to HSF faces. Moreover, the M170 amplitude was larger for LSF faces than for LSF places, whereas the reverse pattern was evident for HSF faces and places. These results suggest that spatial frequency modulates the processing of category specific information for faces and places.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1662-5161 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 67  
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Author Nahab, Fatta; Kundu, Prantik; Gallea, Cecile; Kakareka, John; Pursley, Randy; Pohida, Tom; Miletta, Nathaniel; Friedman, Jason; Hallett, Mark pdf  doi
openurl 
  Title The neural processes underlying self-agency Type Journal Article
  Year 2011 Publication Cerebral Cortex Abbreviated Journal  
  Volume 21 Issue 1 Pages 48-55  
  Keywords  
  Abstract (up) Self-agency (SA) is the individual’s perception that an action is the consequence of his/her own intention. The neural networks underlying SA are not well understood. We carried out a novel, ecologically valid, virtual-reality experiment using BOLD-fMRI where SA could be modulated in real-time while subjects performed voluntary finger movements. Behavioral testing was also performed to assess the explicit judgment of SA. Twenty healthy volunteers completed the experiment. Results of the behavioral testing demonstrated paradigm validity along with the identification of a bias that led subjects to over- or underestimate the amount of control they had. The fMRI experiment identified two discrete networks. These leading and lagging networks likely represent a spatial and temporal flow of information, with the leading network serving the role of mismatch detection and the lagging network receiving this information and

mediating its elevation to conscious awareness, giving rise to SA.
 
  Address  
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  Language Summary Language Original Title  
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  Notes Approved no  
  Call Number Penn State @ write.to.jason @ Serial 21  
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Author Frenkel-Toledo, S.; Liebermann, D.G.; Bentin, S.; Soroker, N. url  doi
openurl 
  Title Dysfunction of the Human Mirror Neuron System in Ideomotor Apraxia: Evidence from Mu Suppression Type Journal Article
  Year 2016 Publication Journal of Cognitive Neuroscience Abbreviated Journal J Cogn Neurosci  
  Volume Issue Pages  
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  Abstract (up) Stroke patients with ideomotor apraxia (IMA) have difficulties controlling voluntary motor actions, as clearly seen when asked to imitate simple gestures performed by the examiner. Despite extensive research, the neurophysiological mechanisms underlying failure to imitate gestures in IMA remain controversial. The aim of the current study was to explore the relationship between imitation failure in IMA and mirror neuron system (MNS) functioning. Mirror neurons were found to play a crucial role in movement imitation and in imitation-based motor learning. Their recruitment during movement observation and execution is signaled in EEG recording by suppression of the lower (8-10 Hz) mu range. We examined the modulation of EEG in this range in stroke patients with left (n = 21) and right (n = 15) hemisphere damage during observation of video clips showing different manual movements. IMA severity was assessed by the DeRenzi's standardized diagnostic test. Results showed that failure to imitate observed manual movements correlated with diminished mu suppression in patients with damage to the right inferior parietal lobule and in patients with damage to the right inferior frontal gyrus pars opercularis-areas where major components of the human MNS are assumed to reside. Voxel-based lesion symptom mapping revealed a significant impact on imitation capacity for the left inferior and superior parietal lobules and the left post central gyrus. Both left and right hemisphere damages were associated with imitation failure typical of IMA, yet a clear demonstration of relationship to the MNS was obtained only in the right hemisphere damage group. Suppression of the 8-10 Hz range was stronger in central compared with occipital sites, pointing to a dominant implication of mu rather than alpha rhythms. However, the suppression correlated with De Renzi's apraxia test scores not only in central but also in occipital sites, suggesting a multifactorial mechanism for IMA, with a possible impact for deranged visual attention (alpha suppression) beyond the effect of MNS damage (mu suppression).  
  Address Loewenstein Hospital, Ra'anana, Israel  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0898-929X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:26942323 Approved no  
  Call Number Serial 82  
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Author Berman, S.; Liebermann, D.G.; McIntyre, J. url  doi
openurl 
  Title Constrained Motion Control on a Hemispherical Surface – Path Planning Type Journal Article
  Year 2014 Publication Journal of Neurophysiology Abbreviated Journal J Neurophysiol  
  Volume 111 Issue 5 Pages 954-968  
  Keywords Constrained motion; geodesics; path planning  
  Abstract (up) Surface-constrained motion, i.e., motion constraint by a rigid surface, is commonly found in daily activities. The current work investigates the choice of hand paths constrained to a concave hemispherical surface. To gain insight regarding the paths and their relationship with task dynamics, we simulated various control policies. The simulations demonstrated that following a geodesic path is advantageous not only in terms of path length, but also in terms of motor planning and sensitivity to motor command errors. These stem from the fact that the applied forces lie in a single plane (that of the geodesic path itself). To test whether human subjects indeed follow the geodesic, and to see how such motion compares to other paths, we recorded movements in a virtual haptic-visual environment from eleven healthy subjects. The task was comprised of point-to-point motion between targets at two elevations (30 degrees and 60 degrees ). Three typical choices of paths were observed from a frontal plane projection of the paths: circular arcs, straight lines, and arcs close to the geodesic path for each elevation. Based on the measured hand paths, we applied k-means blind separation to divide the subjects into three groups and compared performance indicators. The analysis confirmed that subjects who followed paths closest to the geodesic produced faster and smoother movements, compared to the others. The 'better' performance reflects the dynamical advantages of following the geodesic path, as shown by the simulations, and may also reflect invariant features of the control policies used to produce such a surface-constrained motion.  
  Address Ben-Gurion University of the Negev  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3077 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24259548 Approved no  
  Call Number Serial 72  
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Author Friedman, J.; Raveh, E.; Weiss, T.; Itkin, S.; Niv, D.; Hani, M.; Portnoy, S. url  doi
openurl 
  Title Applying Incongruent Visual-Tactile Stimuli during Object Transfer with Vibro-Tactile Feedback Type
  Year 2019 Publication Journal of Visualized Experiments : JoVE Abbreviated Journal J Vis Exp  
  Volume 147 Issue Pages e59493  
  Keywords  
  Abstract (up) The application of incongruent sensory signals that involves disrupted tactile feedback is rarely explored, specifically with the presence of vibrotactile feedback (VTF). This protocol aims to test the effect of VTF on the response to incongruent visual-tactile stimuli. The tactile feedback is acquired by grasping a block and moving it across a partition. The visual feedback is a real-time virtual presentation of the moving block, acquired using a motion capture system. The congruent feedback is the reliable presentation of the movement of the block, so that the subject feels that the block is grasped and see it move along with the path of the hand. The incongruent feedback appears as the movement of the block diverts from the actual movement path, so that it seems to drop from the hand when it is actually still held by the subject, thereby contradicting the tactile feedback. Twenty subjects (age 30.2 +/- 16.3) repeated 16 block transfers, while their hand was hidden. These were repeated with VTF and without VTF (total of 32 block transfers). Incongruent stimuli were presented randomly twice within the 16 repetitions in each condition (with and without VTF). Each subject was asked to rate the difficulty level of performing the task with and without the VTF. There were no statistically significant differences in the length of the hand paths and durations between transfers recorded with congruent and incongruent visual-tactile signals – with and without the VTF. The perceived difficulty level of performing the task with the VTF significantly correlated with the normalized path length of the block with VTF (r = 0.675, p = 0.002). This setup is used to quantify the additive or reductive value of VTF during motor function that involves incongruent visual-tactile stimuli. Possible applications are prosthetics design, smart sport-wear, or any other garments that incorporate VTF.  
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  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1940-087X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:31180348 Approved no  
  Call Number Serial 101  
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