QUANTITATIVE MRI OF THE TEMPORAL-LOBE, AMYGDALA, AND HIPPOCAMPUS IN NORMAL HUMAN-DEVELOPMENT - AGES 4-18 YEARS

The volume of the temporal lobe, superior temporal gyrus, amygdala, an d hippocampus was quantified from magnetic images of the brains of 99 healthy children and adolescents aged 4-18 years. Variability in volum e was high for all structures examined. When adjusted for a 9% larger total cerebral volume in males, there were no significant volume diffe rences between sexes. However, sex-specific maturational changes were noted in the volumes of medial temporal structures, with the left amyg dala increasing significantly only in males and with the right hippoca mpus increasing significantly only in females. Right-greater-than-left laterality effects were found for temporal lobe, superior temporal gy rus, amygdala, and hippocampal volumes. These results are consistent w ith previous preclinical and human studies that have indicated hormona l responsivity of these structures and extend quantitative morphologic findings from the adult literature. In addition to highlighting the n eed for large samples and sex-matched controls in pediatric neuroimagi ng studies, the information from this understudied age group may be of use in evaluating developmental hypotheses of neuropsychiatric disord ers. (C) 1996 Wiley-Liss, Inc.