Experience-dependent modulation of category-related cortical activity.
Naming pictures of objects from different categories (e.g. animals or tools) evokes maximal responses in different brain regions. However, these 'category-specific' regions typically respond to other object categories as well. Here we used stimulus familiarity to further investigate category representation. Naming pictures of animals and tools elicited category-related activity in a number of previously identified regions. This activity was reduced for familiar relative to novel stimuli. Reduced activation occurred in all object responsive areas in the ventral occipito-temporal cortex, regardless of which category initially produced the maximal response. This suggests that object representations in the ventral occipito-temporal cortex are not limited to a discrete area, but rather are widespread and overlapping. In other regions (e.g. the lateral temporal and left premotor cortices), experience-dependent reductions were category specific. Together, these findings suggest that category-related activations reflect the retrieval of information about category-specific features and attributes.
Chao
Linda L
LL
Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD, USA. llchao@itsa.ucsf.edu
Weisberg
Jill
J
Martin
Alex
A
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods