VARIABILITY OF HUMAN BRAIN STRUCTURE SIZE - AGES 4-20 YEARS

Understanding variability of human brain structure sizes during develo pment is important for the design and interpretation of pediatric neur oimaging studies. In this study we analyze the effects of hemisphere, sex and age on size variability of the total cerebrum, cerebellum, lat eral ventricles, temporal lobe, amygdala, hippocampus, superior tempor al gyrus, corpus callosum, caudate, putamen, and globus pallidus in 11 5 healthy children and adolescents, ages 4-20 years. Variability diffe red significantly across structures, with the lateral ventricles demon strating the highest coefficient of variation and the putamen the lowe st. Males varied significantly more than females in the left cerebrum and left superior temporal gyrus, whereas females varied more than mal es in the right caudate and right putamen. Age effects were seen in in creased variability after puberty for the lateral ventricles, hippocam pus and superior temporal gyrus. These variances are important determi nants of minimum sample sizes required to detect group differences in both cross-sectional and longitudinal studies. (C) 1997 Elsevier Scien ce Ireland Ltd.