Hippocampus anatomy These limbic structures include the hippocampus, cingulate cortex, olfactory cortex, and amygdala. Paul MacLean once suggested, as part of his triune brain theory, that the limbic structures constitute the neural basis of emotion. While most neuroscientists no longer believe in the concept of a unified "limbic system", these regions are highly interconnected and do interact with one another. Starting at the dentate gyrus and working inward along the S-curve of the hippocampus means traversing a series of narrow zones. The first of these, the dentate gyrus (DG), is actually a separate structure, a tightly packed layer of small granule cells
Memory and trauma traumatic event is post-traumatic stress disorder, discussed in depth later in the article. Damage to different areas of the brain can have varied effects on memory. The temporal lobes, on the sides of the brain, contain the hippocampus and amygdala, and therefore have a lot to do with memory transition and formation. Patients who have had injury to this area have experienced problems creating new long-term memories. For example, the most studied individual in the history of brain research, HM, retained his previously stored long-term memory as well as functional short-term memory, but was unable to remember anything after it