Trait motivation is associated with fusiform face area morphometry.

Trait motivation is fundamental in shaping human behaviors. Previous studies have primarily focused on their impact on affective and motivational processing, with their role in perceptual processes less investigated. The present study takes face perception, a crucial and well-studied perceptual process, as a representative specimen to examine the perceptual effect of trait motivation. We investigated whether the behavioral activation system (BAS) and the behavioral inhibition system (BIS) were associated with structural characteristics of the inferior temporal face-selective regions as well as face recognition performance. With a sample of Chinese young adults (N = 264), voxel-based morphometry revealed that BIS scores correlated with greater gray matter volume in the fusiform face area. Further, a higher BIS score was associated with slightly better performance in face recognition. These findings provide novel evidence that trait motivation, particularly behavioral inhibition, is linked to both the structure and function of the face processing system. This underlines the intrinsic coupling between motivational and perceptual systems, blurring the presumed divide between affective and perceptual processes.