Engram (neuropsychology)

Engram (from the Greek en, " in," and gramma, " inscription ") is a general term for a physiological track that leaves a stimulus effect as a permanent structural change in the brain. The totality of all engrams - there are billions - results in memory.

After Richard Semon (1904 ) an engram is an experience impression that leaves a memory trace and thus is an element of memory. This view presupposes the property of organic matter to maintain memory traces longer.

Karl Lashley undertook extensive but unsuccessful research to locate engrams in the brain. However, he sought only in the cortex of the brain. Richard F. Thompson sought engrams contrast, in the cerebellum ( cerebellum ).

Donald O. Hebb, the founder of all physiological theories of memory, confirmed 1949, the observations of his predecessors in his studies on memory contents. He talked about the theory of ground-in orbits. An engram can therefore Aristotle illustrated by the image that expresses a signet ring in wax.

According to current understanding engrams can be found in the excitation lines. The idea that one or more locally circumscribable neurons saved each an engram, is obsolete (keyword: grandmother neuron ).

Synapses ( points of contact between two nerve cells to chemical or electrical signal transmission ) can be changed by frequent use, prolonged disuse or coincidence (reinforced, reformed or dissolved ). Thus, the excitation lines and so the engrams change.

Ultimately realize engrams function. In any action and any situation, the brain relies on engrams.