limbic system

The limbic system is a set of deep brain structures—including the amygdala, hippocampus, and parts of the hypothalamus—that process emotions, memory, motivation, and threat detection. It is sometimes called the "emotional brain" because of its central role in how we feel, react, and remember.

In trauma, the limbic system can become overactive and hair-trigger. The amygdala may fire alarms in response to cues that resemble past danger, even when the present situation is safe, while the hippocampus can struggle to place memories in the correct time and context—making old experiences feel like they are happening now. Much of trauma-informed work (somatic therapies, EMDR, breathwork, attuned relationships) is aimed at helping the limbic system settle so the body can learn that the danger is over.