Abstract
The human ventral occipitotemporal cortex (VOTC) contains clusters that are preferentially activated by different domains of objects. A currently prevailing hypothesis is that VOTC functionality is driven by its large-scale connections that support humans' different interactions with various domains of object: manipulation for small artifacts, navigation for scenes, and social interaction for conspecific entities. To test this hypothesis, we trained participants to learn associating meaningless graphs with these three types of human-object interactions by watching cartoons. BOLD fMRI responses were collected for the following sessions: viewing of the graph (one back task), cartoon watching for the three types of interactions with the graphs, viewing of the graph (one back task). The following results were obtained: 1) watching cartoons of human figures performing the three types of interactions with the same graphs elicited whole-brain activation patterns that generally corresponded to the domain-specific regions for artifacts, scenes, and faces/humans, respectively; 2) in VOTC, the lateral occipital temporal cortex (LOTC) was selectively activated when watching manipulation cartoons and the parahippocampal place area (PPA) when watching navigation cartoons; 3) the functional connectivity strength between LOTC and another manipulation-activated region (supramarginal gyrus) during the manipulation learning significantly predicted how strong the LOTC activity to graph viewing changed by training, and also how well the participant memorized the graph-manipulation association. No such effects were observed for PPA. In summary, establishing the mapping between a visual object and a type of manipulation, supported by the functional coupling between LOTC and supramarginal gyrus, induced the domain-specific activation changes for visual perception in LOTC. The social interaction and navigation interaction, however, did not have such an effect on the VOTC activation. These findings highlight the role of human interaction and functional coupling among relevant networks for the LOTC's domain-specific activation for small artifacts.
Meeting abstract presented at VSS 2017