Theories regarding organic determinants of learning and behavior disorders are reviewed historically. Cases illustrating how a bio-ecologic examination can isolate the substances to which a person reacts and some of the reasons for those reactions are presented; and the role of various disorders in relation to the central nervous system is discussed. From ancient times, it has been observed that reactions do occur to environmental substances. Case studies of five children (2 to 12 years old) demonstrate that reactions to environmental substances do occur, and that these reactions are observed to be metabolic disorders stemming largely from a state of addiction (sometimes with genetic predispositions) rather than stemming from allergies. Discussions cover the role of immunologic and nonimmunologic inflamatory reactions, adaptive addiction, endorphins, disordered amino acid metabolism, approach and avoidance, tranquilizers, and anticonvulsants. The appendix, which makes up the bulk of the document, details the five case histories. Presented within each case study are sections on the initial examination and history, methods of laboratory examination, results of laboratory examination, formulation, treatment, prognosis, and diagnoses (including listings of foods causing allergic reactions). Among formulations from the cases are the following: a cause and effect relationship between central nervous system malfunction and environmental substances both in foods and chemicals was established in a 6-year-old girl; specific goods evoked a wide assortment of central nervous system symptoms in a 7-year-old girl, including grimacing, tension, irritability, shaking, and hyperactivity; and a 12-year-old boy was found to have depressive and hyperactive reactions to several foods. (SW)