memory disorder
any impairment in the ability to encode, retain, or retrieve information or representations of experiences. A notable example is amnesia. Memory disorders may be partial or global, mild or severe, permanent or transitory, and anterograde (pertaining to difficulty with new information) or retrograde (pertaining to difficulty with previously known information). The causes include medical conditions leading to structural lesions of the brain or metabolic disruption of brain function, aging, psychological trauma, fugue states, or intrapsychic conflicts.