- Date: 1618
- 1 : loss of memory due usually to brain injury, shock, fatigue, repression, or illness
- 2 : a gap in one's memory
- 3 : the selective overlooking or ignoring of events or acts that are not favorable or useful to one's purpose or position
Amnesia (from Greek Ἀμνησία) is a condition in which memory is disturbed or lost. Memory in this context refers either to stored memories or to the process of committing something to memory. The causes of amnesia have traditionally been divided into the "organic" or the "functional". Organic causes include damage to the brain, through physical injury, neurological disease or the use of certain (generally sedative) drugs. Functional causes are psychological factors, such as mental disorder, post-traumatic stress or, in psychoanalytic terms, defense mechanisms. Amnesia may also appear as spontaneous episodes, in the case of transient global amnesia.