Poster D36, Monday, March 26, 8:00-10:00 am, Exhibit Hall C
Functional Parcellation of the Temporo-Parietal Junction in Individual Subjects
Kathryn Devaney1, Emily Levin2, James Higgins3, David Somers1; 1Boston University, 2Brown University, 3Northwestern University
Activation in the temporo-parietal junction (TPJ) has been reported for attentional capture, theory of mind (ToM), and interruption of a planned motor response (“Stop Signal” (SS)). Possibly, each of these tasks is implicitly recruiting a common cognitive component (e.g. expectation violation, contextual updating). Alternatively, the large area referred to as “the TPJ” could comprise discrete modules recruited separately, with distinctions lost by spatial blurring in group averages. Here, we investigate TPJ functional response properties by performing sustained attention, attention capture, ToM, and SS tasks in the same subjects (n=10, 2mm voxels) across two fMRI scan sessions. Within our subjects, sustained attention deactivation was evident in 12/20 hemispheres, ToM activation in 16/20, SS in 15/20 and attentional capture in 17/20. In individual hemispheres, ToM areas are located on the posterior dorsal segment of the TPJ in angular gyrus. Attention capture activation is located anterior and ventral to ToM, overlapping with the fundus of the superior temporal sulcus (STS) and extending into supramarginal gyrus (SMG). SS activation is localized anterior to the STS in the SMG. We find overlap between deactivation for sustained attention and activation for ToM (dice coefficient = 0.18 ± 0.04) and overlap in activation for attentional capture and SS (dice coefficient = 0.22 ± 0.04). These results demonstrate that 1) ToM regions overlap with default mode network regions and 2) SS and attentional capture recruit an overlapping area in the anterior TPJ, suggesting that these two processes recruit a common cognitive component, perhaps related to expectation violation.
Topic Area: EXECUTIVE PROCESSES: Other