Hunger, Satiety, and Their Vulnerabilities.

Area of Science:

• Neuroscience
• Psychology
• Gastroenterology

Background:

• Hunger and satiety are key regulators of human food intake.
• These states are associated with declarative learning and memory, primarily involving the medial temporal lobes (MTL).
• The MTL, including the hippocampus, is particularly susceptible to damage.

Purpose of the Study:

• To investigate the impact of conditions with medial temporal lobe (MTL) pathology on hunger and satiety.
• To examine conditions central to ingestive behavior (Western diet, obesity, anorexia nervosa) and those with significant MTL pathology but not primarily related to eating (temporal lobe epilepsy, PTSD).

Main Methods:

• Review of existing evidence linking MTL pathology to ingestive behavior and appetite regulation.
• Analysis of conditions with known MTL involvement, including those affecting eating and those not primarily related to it.

Main Results:

• Evidence suggests a link between medial temporal lobe (MTL) impairment and dysfunctional hunger and satiety signals.
• This association appears present in conditions like obesity, anorexia nervosa, temporal lobe epilepsy, and PTSD, though evidence varies in strength.

Conclusions:

• Medial temporal lobe (MTL) dysfunction is implicated in altered appetite regulation.
• Declarative learning and memory processes are critical for maintaining normal hunger and satiety.
• Targeting MTL and memory functions may offer new avenues for appetite control therapies.