Memory and trauma the one most commonly affected by psychological trauma is long-term memory. Missing memories, changes to memory, intensified memories – all are cases of manipulations of long-term memory. Long-term memory is associated with many different areas of the brain including the hippocampus, amygdala, thalamus and hypothalamus, peripheral cortex and temporal cortex. The hippocampus and amygdala have been connected with transference of memory from short-term memory to long-term memory. Thalamus and hypothalamus, located in the forebrain, are part of the limbic system; they are responsible for regulating different hormones and emotional and physical reactions to situations, including emotional stress or trauma. The
Long-term memory be needed to preserve long term memories. Individual retrievals can take place in increasing intervals in accordance with the principle of spaced repetition. This can happen quite naturally through reflection or deliberate recall (also known as recapitulation), often dependent on the perceived importance of the material. Using testing methods as a form of recall can lead to the testing effect, which aids long term memory through information retrieval and feedback. Some theories consider sleep to be an important factor in establishing well-organized long-term memories. "(See also sleep and learning.)" Sleep plays a key function in the consolidation of new memories.