Figure 1.

Stress hormones enhance memory formation. Exposure to a fearful event rapidly activates the autonomic nervous system and enhances norepinephrine levels in the brain. At the same time the hypothalamo–pituitary-adrenal (HPA) axis is activated which causes a slow increase in plasma corticosterone levels. These hormones act via their receptors, which are present in regions that are critical for memory formation such as hippocampus, amygdala, and prefrontal cortex, to promote memory consolidation. For details see text. LC: Locus Coeruleus, Prefr. Cortex: Prefrontal Cortex.