Colloquium at Center for Neural Basis of Cognition

115 Mellon Institute - conference room

Friday Oct 1 at 12.30 p.m.

All welcome



Dr Ehud Zohary

Department of Neurobiology, Hebrew University, Jerusalem

What happens to the visual cortex when the eyes can't see.



Abstract:

The visual cortex may be more modifiable than previously considered. Using

fMRI in ten congenitally blind participants, we report robust occipital

activation during a verbal-memory task (in the absence of any sensory

input), as well as during verb-generation and Braille reading.  We also

found evidence for reorganization and specialization of the occipital

cortex, along the anterior-posterior axis. While anterior regions showed

preference for Braille, posterior regions (including V1) demonstrated

preference for verbal-memory and verb-generation (which both require

memory of verbal material). No such occipital activation was found in

sighted. This difference between the groups was mirrored by superior

performance of the blind in various verbal-memory tasks. Moreover, the

magnitude of V1 activation during the verbal-memory condition was highly

correlated with the blind individual's abilities in a variety of

verbal-memory tests, suggesting that the additional occipital activation

may have a functional role.



_________________________________

Professor, Cognitive Neuroscience

Department of Psychology

Carnegie Mellon University

Pittsburgh, PA 15213-2890

behrmann@cnbc.cmu.edu

412-268-2790 (office)

412-268-2798 (fax)