Prof. Merav Ahissar

Prof. Merav
Ahissar
Faculty of Social Sciences, Mount Scopus, The Hebrew University of Jerusalem, Jerusalem 91905
 Short Bio: The relations between psychological phenomena and their underlying physiological mechanisms have always fascinated me. I began my scientific career with single unit electrophysiology in behaving monkeys. I continued with psychophysics, studying perceptual learning in adult humans. In the past few years I have focused on even higher level skills. We are now studying the relations between perception and cognition. Specifically, we are trying to decipher the perceptual deficits of reading and learning disabled individuals and the relevance of these perceptual deficits to their cognitive disabilities.Research Topics:Auditory perceptual learning: putting it within a consistent conceptual framework (does it follow RHT predictions?) using behavioral, ERP and MEG measurements.Perceptual plasticity: A search for a unified framework for studying the various manifestations of perceptual plasticity: Perceptual learning. Adaptation. Priming. What is the role of top-down control in each of these phenomena?Reverse Hierarchy Theory: Exploring further the theory of reverse hierarchy (Ahissar & Hochstein, 1997) in the general context of perception. The perceptual basis of cognitive abilities: What (if any) are the perceptual deficits that underlie cognitive difficulties in the general population? Are there cognitive "primitives"? Can they be probed with perceptual tasks?The perceptual basis of reading and learning disabilities: What are the main visual and auditory processing difficulties that learning disabled suffer from? In what way are they functionally linked to their cognitive difficulties.The relations between perception in the lab using simple, out of context, stimuli and natural perception: The project aims to assess the dynamics of visual processing as revealed by behavior, patterns of eye movements and ERP. Particularly, to what extent global stimulus characteristics dominate initial perception compared with local aspects that do not impact the categorical level (i.e. assessing RHT predictions) in the general population and among dyslexics.Recent Publications:Weiss, AH, Granot RY, Ahissar M.  2014.  The enigma of dyslexic musicians. Neuropsychologia. 54:28-40.Raviv, O, Lieder I, Loewenstein Y, Ahissar M.  2014.  Contradictory behavioral biases result from the influence of past stimuli on perception. PLoS Comput. Bio. 10(12):e1003948.Cohen, Y, Daikhin L, Ahissar M.  2013.  Perceptual learning is specific to the trained structure of information. Journal of cognitive neuroscience. 25(12):2047-60.Banai, K, Ahissar M.  2013.  Musical experience, auditory perception and reading-related skills in children. PloS one. 8(9):e75876.Jacoby, N, Ahissar M.  2013.  What does it take to show that a cognitive training procedure is useful? A critical evaluation. Progress in brain research. 207:121-40.Ramus, F, Ahissar M.  2012.  Developmental dyslexia: The difficulties of interpreting poor performance, and the importance of normal performance. Cognitive neuropsychology. 31 (26): 9658-64.Ahissar, M.  2012.  Perceptual learning. Vision research. 61:1-3.Daikhin, L, Ahissar M.  2012.  Responses to deviants are modulated by subthreshold variability of the standard. Psychophysiology. 49(1):31-42.Oganian, Y, Ahissar M.  2012.  Poor anchoring limits dyslexics' perceptual, memory, and reading skills. Neuropsychologia. 50 (8): 1895-905.Raviv, O, Ahissar M, Loewenstein Y.  2012.  How Recent History Affects Perception: The Normative Approach and Its Heuristic Approximation. PLoS Comput Biol. 8:e1002731.