engram
Pronunciation: EN-gram
The hypothetical physical neural substrate of a specific memory trace within the brain.
Full Definition
An engram represents the enduring physical and biochemical changes in neural circuits that store specific memories. Originally a theoretical concept, modern techniques like optogenetics and calcium imaging now allow researchers to identify and manipulate engram cells - the specific neurons that are active during memory formation and reactivated during recall. Engrams involve distributed networks across multiple brain regions and are characterized by altered synaptic connections and cellular properties. This concept is central to memory research and appears throughout literature on learning, memory storage, and retrieval mechanisms.
Usage
Usage note: Distinguish from general 'memory' - an engram specifically refers to the physical neural substrate.
In Context
- "Optogenetic reactivation of the fear engram triggered memory recall in mice." — Memory research paper
- "The search for the physical engram has driven neuroscience research for decades." — Review article