Human brain development is a structurally and functionally non-linear process (Johnson, 2001; Thatcher, 1992; Thatcher, Walker, & Giudice, 1987) and most major neuropsychiatric disorders are now thought to arise out of deviations from normal brain development, suggesting a neurodevelopmental basis for these disorders. It is therefore important to study both normal and abnormal brain changes with age in order to understand how major neuropsychiatric disorders emerge (Schlaggar et al., 2002; Stiles, 2000). Postmortem studies provide information at molecular and cellular levels, but are limited by the scarcity of human brain tissue, inability to provide information during life, and the inability to use longitudinal designs. Noninvasive brain imaging, with recent advances in the resolution of MRI and in mapping methodology, provides a unique alternative to study brain development during life, allowing studies that assess the same individual or group of subjects repeatedly. This allows the dynamic trajectory of an illness, or the profile of cortical development throughout childhood and adolescence, to be visualized as a time-lapse map, presenting statistics on the 3D profiles of brain changes at different ages (Thompson et al., 2001; Gogtay et al., 2004, 2007, 2008).
