The hippocampus mainly controls how you form, store, and use memories, and how you navigate through space. It also helps regulate emotions, decision‑making under uncertainty, and communicates with hormone and stress systems in the brain.

What the hippocampus controls

  • Forming new memories (especially facts and life events, called declarative/episodic memory).
  • Converting short‑term memories into long‑term storage (memory consolidation).
  • Learning new information and skills that depend on remembering facts, places, and contexts.
  • Spatial navigation and “mental maps” of environments, helping you know where you are and how to get around.
  • Visual‑spatial memory: remembering where objects are and how your body is positioned in space.
  • Verbal memory: recalling words, names, and what was said in conversations.

Emotional and decision roles

  • Linking memories with emotions by working closely with the amygdala (e.g., remembering a frightening or joyful event as emotionally charged).
  • Participating in decision‑making in uncertain, conflict‑filled situations, especially when choices can be both risky and rewarding.
  • Helping regulate motivation and some aspects of emotional behavior (such as anxiety‑related responses).

Hormones, stress, and the body

  • Communicating with the hypothalamus and pituitary to provide feedback that influences hormone release.
  • Being highly sensitive to stress hormones; chronic stress can reduce hippocampal activity and harm memory.
  • Contributing to the “fight‑or‑flight” response as part of the limbic system, by feeding memory and context into stress‑response circuits.

What happens when it’s damaged

  • Difficulty forming new memories (you may remember your past but struggle to remember new conversations or events).
  • Getting lost easily or having trouble navigating even familiar places.
  • Problems recalling words, names, and recent facts.

In short, when you ask “what does the hippocampus control,” the best answer is: it controls the formation and organization of memory, your internal map of space, and important links between memory, emotion, decision‑making, and stress.

Information gathered from public forums or data available on the internet and portrayed here.