Transient amnesia may occur following an epileptic episode. This needs to be distinguished from total global amnesia (TGA). It may be related to ictal activity involving the mesial temporal lobes, resulting in disruption of memory consolidation during sleep.


Diagnostic features of Transient Epileptic Amnesia (TEA):

(1) history of recurrent episodes of transient amnesia

(2) cognitive functions other than memory must be judged intact during a typical episode by a reliable witness.

(3) evidence of underlying partial epilepsy


The period covered by amnesia may involve a period from hours to a few years. The transient amnesia may affect:

(1) antegrade memory

(2) retrograde memory

(3) both


Evidence of underlying partial epilepsy involves 1 or more of the following:

(1) reproducible epileptiform discharges on EEG

(2) co-occurrence of other seizure types (if concurrent onset or close association with episodes of transient amnesia suggests a connection)

(3) a clear-cut response to anticonvulsant therapy (with abolition or definite reduction in frequency of amnesic episodes)


Other features of TEA:

(1) tends to occur in older adults, usually males

(2) patients often give a history of heart disease

(3) commonly occur upon waking from sleep

(4) average of 3 episodes per year (TGA only rarely recurs within 1 year)

(5) may affect verbal and nonverbal memory (TGA affects verbal memory more selectively)


To read more or access our algorithms and calculators, please log in or register.