POSITIVE AND NEGATIVE ASPECTS OF HYPOTHALAMIC DISORDERS

Abstract

The effects of chronic hypothalamic lesions in man are compared with those induced experimentally. The former develop slowly with adequate time for the establishment of compensatory circuits which travel over alternate pathways. The latter are acute lesions, with massive and dramatic immediate results. Differences in localization also cause variability, as does the age of the patient. Accompanying extra-hypothalamic cerebral disturbances may be a factor. Although the dorso-medial, ventro-medial and lateral nuclei influence vegetative function, it has not been proved that recognized metabolic disorders originate from distinct anatomical "centers." Thus the diabetes insipidus syndrome does not always result from bilateral destruction of the supra-optic nuclei. There is much evidence that frequently used pathways are followed for economic reasons but that alternates can be called into play when there is interruption of the main circuit. Although the study of vegetative function is focused on the hypothalamus the cerebral cortex is known to play a part, functional localization in the latter being diffuse. Both positive and negative aspects should be studied with equal care.