Development of Higher Brain Functions: Birth Through Adolescence

Abstract

The bane of pain in understanding the healthy, normal, developing brain lay vainly in the unfolding story of life’s unfinished experiment as to what we know and do not know regarding ‘‘what’s going on age-wise’’ and how mapping structure onto function looks from birth through adolescence. Higher cortical functions in humans, birth through adolescence, proceed in defined age-related changes that influence structure–function relationships. In a five-year NIH-funded, multi-center project on ‘‘Normal (healthy) Brain Development (birth through 18),’’ findings from this report released in July 2006 are now available to the public via Brain Imaging Resource Network, which contains a comprehensive database on 500 human children with information collected from a wide variety of sources, e.g., MRI, neural, cognitive, intellectual, behavioral, and social demographic variables. Significant limitations in our knowledge exist as to the processes involved in the normal developing human brain with respect to neurophysiological, neurochemical, neuroanatomical, metabolic, and other related neuroscience disciplines. Attempts have been made to correlate anatomical and behavioral data in a direct manner, leading to a surfeit of postulations in the literature against a shortage of supporting data for known brain–behavior relationships in children (Taylor, Fletcher, & Satz, 1984). Much emphasis tends to be placed on proposed neural mechanisms and theories accounting for changes regarding development of the human central nervous system (CNS) versus description of changes taking place with respect to normal development of the human brain.Major difficulties exist in drawing fixed conclusions because each human brain is unique with respect to its molecular blueprint, cellular differentiation pattern, acculturation factors, and neural growth patterns (Cooke, 1980; McConnell, 1991). Luria (1969a, personal communication, 1977) stressed that what was lacking in the area of clinical child neuropsychology was an integrative scheme outlining a conceptual blueprint of normal brain development with concomitant motor, sensory, perceptual, and cognitive processes involved in children’s higher cortical functions. During the past 10 years, however, neuroimaging and brain metabolism (MRI, MRS, FMRI, MegEEG, MSI, PETT imaging) technologies are producing quantitative means of mapping human brain function onto brain structure (Kreis, Ernst, & Ross, 1993; Raichle, 1987; Raichle et al., 1994; Reynolds, McCormick, Roth, Edwards, & Wyatt, 1991; Stehling, Turner, & Mansfield, 1991; Tzika, Vigneron, Ball, Dunn, & Kirks, 1993). LAWRENCE V. MAJOVSKI AND DAVID BREIGER Department of Psychiatry and Behavioral Sciences, Children’s Hospital and Regional Medical Center, University of Washington School of Medicine, Seattle, Washington 98104–2499.