Background: The structure and function of the superior temporal gyrus (STG), a structure involved in receptive and nonverbal auditory and language processing, is understudied in posttraumatic stress disorder (PTSD). Event-related potential abnormalities were previously reported in PTSD, implicating the existence of dysfunction in the primary auditory cortex and adjacent anterior auditory cortex of the STG in adult PTSD.
Methods: Anatomic magnetic resonance imaging (MRI) volumetric analysis of the superior temporal gyrus were performed in 43 maltreated children and adolescents with PTSD and 61 nonmaltreated healthy control subjects.
Results: Unadjusted STG gray matter volumes were larger in maltreated subjects with PTSD than in control subjects, whereas STG white matter volumes were smaller in maltreated subjects with PTSD than in control subjects. After adjusting for differences in cerebral volume, right, left, and total superior temporal gyrus volumes were relatively larger in PTSD subjects compared with control subjects. After covarying for differences in cerebral gray matter volumes, regression analysis showed that PTSD subjects had significantly greater STG gray matter volumes in most, and in particularly right-sided STG measurements. Furthermore, findings of significant side-by-diagnosis interactions for STG and STG gray but not white matter STG volumes suggest that there is a more pronounced right > left asymmetry in total and posterior STG volumes but a loss of the left > right asymmetry seen in total, anterior, and posterior STG gray matter volumes in PTSD subjects compared with control subjects.
Conclusions: These STG findings may suggest developmental alterations in maltreatment-related pediatric PTSD.