Transient epileptic amnesia--a clinical update and a reformulation.

While absence attacks and complex partial seizures have been well documented in patients with epilepsy, the delineation of pure episodes of memory loss without additional clinical manifestations remains poorly characterised. The recently described condition of transient epileptic amnesia (TEA) is critically examined, and four new cases are described, in each of which there were episodes of pure memory loss which subsequently proved to be epileptic in origin. The anatomical and pathophysiological basis of TEA is presumed to be similar to transient global amnesia (TGA), that is, it is likely to be primarily hippocampal in origin, but with more variable involvement of limbic and adjacent temporal lobe neocortical structures.