The description of sequelae of nutritional deficien­ cies was equally oversimplified. Obviously, a disease like rickets, which affected hard tissues--the skeleton-­ had irreversible consequences. Destruction or alteration of tissues, such as in cancrum oris or severe xerophthal­ mia, was equally permanent and easily observed. Other models were beriberi or scurvy, where, by contrast, the vitamin treatment seemed to restore the individual to the completely normal status quo ante. Most nutritionists were therefore little prepared intellectually for the series of suggestive findings con­ cerning nutrition and mental development which has been the highlight of nutritional research in the past decade: the discovery that there are irreversible gaps in mental development not correlated with obvious permanent somatic lesions which follow acute malnutrition during the develop­ ment of the young infant. Furthermore, not only are ex­ isting somatic instruments--physical examination, the scale, and the measuring tape--inadequate to detect such intellectual and behavioral deficits, but some of the current psychological instruments, bound to traditions of Western culture, are often poorly adapted to measure fine differences in psychological development among poor populations. These initial discoveries have stimulated important methodological advances, ranging from better staining techniques for the study of fibers connecting brain neurons to better tests for the study of cognitive development.

Welcoming Address.- Introductory Remarks.- Introductory Remarks.- Biophysiological Aspects of Animal and Human Brain Growth as Related to Malnutrition.- Long Continued Marginal Protein-Energy Deficiency.- Behavioral Deficiencies in Protein-Deprived Monkeys.- Nutrition and Brain Development.- Malnutrition and Animal Models of Cognitive Development.- Interactive Effects of Variable Population Density and Dietary Protein Sufficiency upon Selected Morphological, Neurochemical, and Behavioral Attributes in the Rat.- Protein Malnutrition and Complex Learning in the Chicken.- Learning in Chronically Protein-Deprived Rats.- Concluding Remarks.- Clinical and Follow-up Studies Related to Mental Functioning of Malnourished Children.- Social Antecedents and Correlates of Preschool Malnutrition in Cambridge, Massachusetts.- Longitudinal Study of Language Development in Severely Malnourished Children.- Nutrition, Environment, and Child Behavior.- The Biochemical Aspects of Nutrition as Related to Mental Illness.- Nutrition and Psychiatric Illness.- Premorbid Adjustment and Response to Nicotinic Acid.- Workshop on Nutrition.- Some Comments of the Effects of Malnutrition on Brain Function.- Critique of Research Dealing with the Consequences of Early Malnutrition, Summary of Discussion at the Workshop on Nutrition.- Summary.- Discussion on Megavitamins.- Reply to "Nutrition and Psychiatric Illness" by Seymour Kety.- Response to Dr. Osmond's Comments.- Remarks on the Use of Megavitamins in the Treatment of Schizophrenia.- Contrasts Between Vitamin-Responsive Inherited Metabolic Diseases and Vitamin Use in Schizophrenia.- The Transmethylation Hypothesis Restated.- Summary.- Comment.- Conclusion.- Closing Remarks.