Final answer:
The amygdala, limbic system, and hypothalamus are critical structures involved in emotion and motivated behavior.
Step-by-step explanation:
The three critical structures involved in emotion and motivated behavior are the amygdala, the limbic system, and the hypothalamus. The amygdala is responsible for processing emotional information and plays a role in fear and recognizing fearful faces. The limbic system regulates emotion, fear, motivation, and memory formation. The hypothalamus is involved in the activation of the sympathetic nervous system during emotional reactions and regulates homeostatic processes, including sexual motivation and behavior.