Hippocampus

There is one hippocampus in each temporal lobe. They are among the most-studied structures in all of neuroscience, because damage to them — from Alzheimer’s, Korsakoff’s syndrome, hypoxic injury, or surgical removal — produces striking memory loss. The hippocampus is the system that binds together the who, what, where, and when of a specific event into something you can later re-experience.

Aphantasia and SDAM both intersect with hippocampal function. Imaging work, including Monzel and colleagues in 2024, has found altered hippocampal activity in aphantasia during tasks that would typically engage imagery-guided recall. In SDAM the hippocampus is often less responsive during autobiographical retrieval than in typical adults. The hippocampus is the most likely handoff point between the general memory system and the specific phenomena aphantasia and SDAM describe.