An fMRI study identifying brain regions activated when performing well-learned versus newly learned visuomotor associations

The current fMRI study identified brain regions implicated in performing well-learned versus new visuomotor associations. Stimuli were 2 sets of 6 abstract images, each paired arbitrarily with a unique hand gesture. Participants rehearsed one set of pairings over 4 days and learned the other set immediately prior to scanning. Data were obtained for 14 participants, who demonstrated an average 76ms motor reaction time advantage when performing the well-learned associations immediately prior to fMRI scanning. Regions-of-interest for the left lateral-occipital (LO), the left anterior intra-parietal (AIP) and left medial intra-parietal (MIP) areas were obtained by an independent functional localizer. Parameter estimates extracted from these regions demonstrate a greater BOLD response in left LO for new compared to well-learned associations (t(13) = 3.322, p = .006), but not left AIP or left MIP. Results suggest the left-hemisphere ventral stream is strongly activated before the automatization of visuomotor associations.