UNIQUE BRAIN MECHANISMS IN HIPPOCAMPUS.

A study was undertaken to test the hypothesis that, since bilateral fornicotomy creates no manifest behavioral deficits in human beings over the age of 7, or in young adult monkeys or cats, the essential functions of the fornices lie within the early behavior formative age of mammals, - by demonstrating some such function. The results indicate that at least the 50 of lateralis-dorsalis neurons known not to project to cortex, have inputs coursing via stria medullaris and fornix from ventral hippocampus, and outputs passing into other thalamic nuclei, - and that this pathway must be activated, on at least one side, when an ongoing innate pattern of appetitive other than reproductive behavior is blocked in a novel setting and requires insightful integration with latent-learned neocortically stored knowledge of the environment. Such activity is seen as a subset of the main function of fornico-thalamic pathways in programming neocortex from allocortex during the behavior-formative period of life, given a problem-rich environment. Author