Source:
2005 Nov;67:285-323.
Author: Thompson PM, Sowell ER, Gogtay N, Giedd JN, Vidal CN, Hayashi KM, Leow A, Nicolson R, Rapoport JL, Toga AW.
Abstract:
MRI scans provide exceptionally detailed information on how the human brain changes throughout childhood,
adolescence, and into old age. We describe several approaches for understanding developmental changes in brain
structures based on MRI. Atlas-based “parcellation” methods, for example, measure volumes of brain
substructures, revealing how they change with age. Growth curves for different brain structures can be compiled,
describing the expected trajectories of normal development. Additional computational anatomy techniques can be
used to map spatial patterns of brain growth and tissue loss in individual children. Changes in cortical features,
such as gray matter thickness, asymmetry, and complexity, can also be mapped. Individual maps can then be
combined across subjects to make statistical maps or dynamic “time-lapse movies” that reveal systematic features
of brain development in population subgroups, while retaining information on their variance. We review several
large-scale studies of brain development, including longitudinal studies in which children were scanned
repeatedly with structural MRI at 2-year intervals for periods of up to ten years. Image processing algorithms
were then applied to recover detailed information from the resulting image databases. We describe the approaches
necessary to compare brain MRI data across groups differing in age, covaried with gender, developmental
disorders, or genotype. These methods reveal unsuspected links between development and cognition, and can help
discover genetic and environmental factors that affect development. These brain maps also chart the anatomical
sequence of healthy brain maturation and visualize how it is derailed in neuropsychiatric disorders such as
schizophrenia, autism, fetal alcohol syndrome, and Williams syndrome.