Neural Correlates of Repetition Priming: Changes in fMRI Activation and Synchrony

The neural mechanisms of behavioural priming remain unclear. Recent studies have suggested that category-preferential regions in ventral occipitotemporal cortex (VOTC) play an important role; some have reported increased neural synchrony between prefrontal cortex and temporal cortex associated with stimulus repetition. Based on these results, I hypothesized that increased neural synchrony, as measured by functional connectivity analysis using functional MRI, between category-preferential regions in VOTC and broader category-related networks would underlie behavioural priming. To test this hypothesis, I localized several category-preferential regions in VOTC using an independent functional localizer. Then, Seed Partial Least Squares was used to assess task-related functional connectivity of these regions across repetition of stimuli from multiple categories during an independent semantic classification task. While the results did not show the hypothesized differences in functional connectivity across stimulus repetition, evidence of category-specificity of neural priming and novel insights about the nature of category-related organization of VOTC were revealed.