Presidential Address: Metabolism and Mentation

The ultimate supreme function of the body is mentation; the other portions of the body are subservient to it. Dysmentation is very common, highly distressing, and enormously expensive. All abnormalities in mentation are presumably associated with altered metabolism. Dysmetabolism causes dysmentation and vice versa. Altered cerebral metabolism is produced by primary or secondary cerebral disorders in the body, and by extracorporeal influences—abnormalities in diet, climate, social status, and numerous other environmental factors; there frequently is a polycyclic interplay of influences. Dysmentation is often found in many genetic disorders, hyperand hypoparathyroidism, hyperand hypoadrenocorticism, and hypothyroidism. There are indications that it also occurs frequently in many other endocrine and metabolic disorders, but data are inadequate. Many neurotransmitters have been described, including especially acetylcholine, norepinephrine, dopamine and serotonin. Abnormalities in the metabolism of one or more of these have been reported in various types of dysmentation. In mental depression and mania there are abnormalities in catecholamine metabolism, with lesser changes in serotonin. Certain observations have suggested abnormalities in serotonin metabolism in schizophrenia, but data remain inadequate. Hallucinations and other marked behavioral changes have accompanied altered serotonin metabolism and/or ingestion of serotonin-like compounds. Changes in acetylcholine levels have produced anger, rage, anxiety and other behavioral states. Sleep seems to be associated with increased serotonin and decreased catecholamine levels; insomnia accompanies the reverse. Learning and memory are influenced by the metabolism of protein, nucleotides, carbohydrate, fat, vitamins, minerals, and numerous other factors. The brain has richer contents of adenosine-3',5'-phosphate, adenyl cyclase and phosphodiesterase than any other organ, but relatively little is known about the functions there of this nucleotide. As endocrinologists and metabolists, problems of dysmentation confront us as highly interesting, and probably richly rewarding areas for research, teaching and practice. (J Clin Endocr 31: 461, 1970) T IHE ULTIMATE supreme function of the body is mentation. Without mentation the body is not of significant use. Mentation plays the major role in all pleasures and pains. All abnormalities in mentation are associated with altered metabolism. Metabolic changes lead to psychic alterations and vice versa; such multicyclic interrelationship often occurs in the same 1 Presented at the 52nd Annual meeting of The Endocrine Society, June 1970. 2 Metabolism is "The sum of all the physical and chemical processes by which living organized substance is produced and maintained, and also the transformation by which energy is made available for the uses of the organism" (Dorland's Medical Dictionary); mentation is the act of thinking. 3 Aided by Grant AM-05020, NIAMD. individual. Moreover, metabolic or psychic abnormalities can lead to changes in other parts of the body which then influence further the metabolic and psychic states. Alterations in the chemical and/or physical status of the brain can be brought about by a large variety of influences. These include primary intracerebral abnormalities, disorders in other parts of the body, and extracorporeal influences, among which are social, climatic, nutritional and numerous other factors. There often is an interplay among these factors. For example, certain genetic enzyme abnormalities in the brain can tremendously alter behavior and, in turn, lead to adverse environmental conditions; contrariwise, abnormal environ-