engrams

Noun

engram (plural engrams)

1. A postulated physical or biochemical change in neural tissue that represents a memory.
   • I use the word engram to denote this permanent change wrought by a stimulus; the sum of such engrams in an organism may be called its "engram-store," among which must distinguish inherited from acquired engrams.1921 January, Richard Semon, “II (Engraphic Action of Stimuli on the Individual)”, in Louis Simon, transl., The Mneme, Cornell University Library, published 2005, page 24
2. A painful, negative mental image representing a past event.

See all 3 meanings of engram