Engram (neuropsychology)

Engram (neuropsychology)

Engrams are a hypothetical means by which memory traces are stored as biophysical or biochemical changes in the brain (and other neural tissue) in response to external stimuli.

They are also sometimes thought of as a neural network or fragment of memory, sometimes using a hologram analogy to describe its action in light of results showing that memory appears not to be localized in the brain. The existence of engrams is posited by some scientific theories to explain the persistence of memory and how memories are stored in the brain. The existence of neurologically defined engrams is not significantly disputed, though their exact mechanism and location has been a focus of persistent research for many decades.