Hippocampus Contributions to Food Intake Control: Mnemonic, Neuroanatomical, and Endocrine Mechanisms

Abstract

Food intake is a complex behavior that can occur or cease to occur for a multitude of reasons. Decisions about where, when, what, and how much to eat are not merely reflexive responses to food-relevant stimuli or to changes in energy status. Rather, feeding behavior is modulated by various contextual factors and by previous experiences. The data reviewed here support the perspective that neurons in multiple hippocampal subregions constitute an important neural substrate linking the external context, the internal context, and mnemonic and cognitive information to control both appetitive and ingestive behavior. Feeding behavior is heavily influenced by hippocampal-dependent mnemonic functions, including episodic meal-related memories and conditional learned associations between food-related stimuli and postingestive consequences. These mnemonic processes are undoubtedly influenced by both external and internal factors relating to food availability, location, and physiological energy status. The afferent and efferent neuroanatomical connectivity of the subregions of the hippocampus is reviewed with regards to the integration of visuospatial and olfactory sensory information (the external context) with endocrine, gustatory, and gastrointestinal interoceptive stimuli (the internal context). Also discussed are recent findings demonstrating that peripherally-derived endocrine signals act on receptors in hippocampal neurons to reduce (leptin, glucagon-like peptide-1) or increase (ghrelin) food intake and learned food reward-driven responding, thereby highlighting endocrine and neuropeptidergic signaling in hippocampal neurons as a novel substrate of importance in the higher-order regulation of feeding behavior.

The anterior medial temporal lobes: Their role in food intake and body weight regulation

“…It is worth noting that similar topics have been the object of several recent reviews (e.g., [5,56,78,98,109,117,139]). They include descriptions of studies linking food intake regulation to the amygdala [5] and the hippocampus Kanoski & Grill [78]; [117]) as well as studies showing the influence of memory on food reward processing [56] and obesity [98], and the impact of other factors such as environment and stress on obesity [109,139].…”

“…They include descriptions of studies linking food intake regulation to the amygdala [5] and the hippocampus Kanoski & Grill [78]; [117]) as well as studies showing the influence of memory on food reward processing [56] and obesity [98], and the impact of other factors such as environment and stress on obesity [109,139]. However, rather than reiterating the material covered by these scholarly works, the present review aims to integrate the literature on the functions of both the amygdala and the hippocampus in food intake and body weight regulation in two unique ways.…”

“…However, "evidence exists for input to the hippocampus from the amygdaloid complex, implicating it in the processing of emotional information and thus indirectly in interoceptive processes" ( [18], p. 120). Moreover, there is accumulating evidence that "dietary factors are associated with the emergence of hippocampal pathology and that hippocampal pathology is associated with the emergence of increased food intake and body weight gain" ( [77], p. 60; see also [78,117]). Three reviews [28,78,117] on the hippocampus' role in food intake have also highlighted the fact that its function in this context is more well-known than the amygdala's (see also the last outstanding question).…”

“…This type of memory has been shown to influence food intake (e.g., [78]). Thus, the recall of previously eaten food leads to a decrease in subsequent food intake [54].…”

Different Endocrine Effects of an Evening Dose of Amitriptyline, Escitalopram, and Placebo in Healthy Participants

“…There, metabolic and sexual functions are controlled directly and release hormones regulate subsequent glands, such as the adrenal glands for peripheral stress regulation (hypothalamic-pituitary-adrenal axis, HPA). For food intake, the antagonistic hormones ghrelin and leptin have been identified as important hypothalamic modulators 5). However, the exact mechanisms of the described adverse effects remain to be further investigated.…”