Homeostasis - 9.4

Hypothalamus

A crucial brain region for regulating metabolic rate, food intake, and body weight.

VMH (Ventromedial Hypothalamus)

Identified as the satiety center; lesions here lead to excessive eating and obesity.

LH (Lateral Hypothalamus)

Known as the hunger center; lesions here cause cessation of eating and rapid weight loss.

Leptin

A hormone released by fat cells that informs the brain about long-term energy reserves.

Ghrelin

A hormone that stimulates appetite and increases before meals; it decreases after eating.

PYY3-36

An intestinal hormone that acts as a satiety signal, rising after meals to suppress appetite.

GLP-1 (Glucagon-like peptide 1)

A hormone that reduces appetite and feeding, secreted in response to nutrient intake.

POMC/CART neurons

Neurons that inhibit appetite and increase metabolism when activated.

NPY/AgRP neurons

Neurons that stimulate appetite and inhibit satiety signals.

Set point theory

The idea that the body has a natural point of stability for body weight, influenced by hormonal signals.

Lesion Studies

Research method showing the effects of targeted brain damage on behavior, particularly appetite regulation.

Satiety signal

Hormone or neural signal indicating fullness and the cessation of eating.

Hunger signal

Hormone or neural signal indicating the need for food intake.