CORTICAL PLASTICITY IN PERCEPTUAL-LEARNING DEMONSTRATED BY TRANSCRANIAL MAGNETIC STIMULATION

Performance on a wide range of perceptual tasks improves with practice . Most accounts of perceptual learning are concerned with changes in n euronal sensitivity or changes in the way a stimulus is represented. A nother possibility is that different areas of the brain are involved i n performing a task white learning it and after learning it. Here we d emonstrate that the right parietal cortex is involved in novel but not learned visual conjunction search. We observed that single pulse tran scranial magnetic stimulation (TMS) to the right parietal cortex impai rs visual conjunction search when the stimuli are novel and require a serial search strategy, but not once the particular search task has be en learned. The effect of TMS returns when a different, novel, serial search task is presented. (C) 1998 Elsevier Science Ltd. All rights re served.