| Sumario: | Human and animal data suggest that the hippocampus plays certain roles in regulating food intake. However, its actual role may be far broader than currently envisaged, a claim suggested by the centrality of the hippocampus to so many aspects of human/animal cognition. Understanding these ingestion-related functions is especially significant. This is because some degree of hippocampal impairment may be quite common, resulting for example from a Western-style diet, insomnia, diabetes, and depression--among many other causes. One potential consequence of hippocampal impairment could be a loosening of food intake regulation, leading in the longer-term to weight gain and its health-related impacts. Here we review known, suspected and newly hypothesized hippocampal-dependent functions involved in regulating human food intake: (a) declarative memory processes, and their use in explicitly evaluating when, what and how much to eat; (b) interoception, as it relates to hunger, fullness and thirst; (c) inhibitory processes, especially as applied to physiological state, place, and time, and their role in modulating memory retrieval; (d) craving and imagery for food; (e) perception of time and its role in preparing the body for food intake and estimating meal length; (f) trace conditioning and nutrient-related learning; and (g) inhibition of the hypothalamic-pituitary-adrenal stress response and stress-related eating. For each we present evidence for hippocampal involvement, describe the putative regulatory role, and the hypothesized effects of hippocampal impairment. We conclude that the hippocampus is inti¬mately involved in regulating human food intake via multiple interconnected pathways, many of which are unstudied and understudied.
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