Functional Organization of Social Perception and Cognition in the Superior Temporal Sulcus

Abstract

The superior temporal sulcus (STS) is considered a hub for social perception and cognition, including the perception of faces and human motion, as well as understanding others' actions, mental states, and language. However, the functional organization of the STS remains debated: Is this broad region composed of multiple functionally distinct modules, each specialized for a different process, or are STS subregions multifunctional, contributing to multiple processes? Is the STS spatially organized, and if so, what are the dominant features of this organization? We address these questions by measuring STS responses to a range of social and linguistic stimuli in the same set of human participants, using fMRI. We find a number of STS subregions that respond selectively to certain types of social input, organized along a posterior-to-anterior axis. We also identify regions of overlapping response to multiple contrasts, including regions responsive to both language and theory of mind, faces and voices, and faces and biological motion. Thus, the human STS contains both relatively domain-specific areas, and regions that respond to multiple types of social information.

Keywords: social cognition; social perception; superior temporal sulcus.

Figure 1.

Individual-subject activations to 7 different contrasts in 2 representative example subjects. Analyses were restricted to the bilateral STS mask shown in yellow at the bottom, and were thresholded at a false discovery rate of q < 0.01. The slices displayed are at MNI x-coordinate ± 52 .

Figure 2.

Responses to each task as a function of position along the length of the STS. The upper figure shows the ROIs that were used to extract responses at each position. The lower 2 graphs show left and right STS responses (percent signal change) for each task, as a function of y-coordinate in MNI space.

Figure 3.

Responses (in percent signal change) of maximally sensitive regions for each contrast, across all conditions. Responses were measured in data independent of those used to define the ROIs.

Figure 4.

Matrices of functional connectivity similarity (correlations between whole-brain resting-state functional connectivity maps of seed ROIs defined by each contrast) and response similarity (correlations between vectors of task responses from each seed ROI). ROIs are defined to consist of a focal region of maximal activation to a given contrast.

Figure 5.

Overlap matrices for regions of activation defined by each task contrast. Each cell in a given overlap matrix is equal to the size of the overlapping region for the tasks on the corresponding row and column, divided by the size of the region of activation for the task on that row, as shown in the graphic on the left-hand side.

Figure 6.

Responses (in percent signal change) of overlapping regions responsive to multiple contrasts, across all conditions. Responses were measured in data independent of those used to define the ROIs.