Temporal activation patterns of lateralized cognitive and task control processes in the human brain

Lexical and visuospatial information processing show hemispheric specialization: Using fMRI and identical word stimuli for both tasks, a recent study study demonstrated left-hemispheric activations (including Broca's area) associated with letter detection decisions (including Broca's area) and right hemisphere activations (posterior parietal cortex, PPC) for visuospatial decisions judgments (Stephan et al. 2003). Importantly, cognitive control was vested in the same hemisphere's anterior cingulate cortex. We performed current source density reconstruction (CDR) of event-related potentials (ERPs) recorded at high…