WADA MEMORY AND TIMING OF STIMULUS-PRESENTATION

We compared Wada memory performance for stimuli presented at two timin g intervals following amobarbital injection in 47 non-lesional patient s with complex partial seizures (L = 26; R = 21). A significant intera ction between seizure focus and timing of presentation was present (P < 0.03). Memory performance for objects whose presentation began appro ximately 50-55 s following amobarbital administration differed as a fu nction of ipsilateral vs. contralateral injection at a very high level of statistical significance (P < 0.00001). Items presented approximat ely 4 min, 30 s post injection were also related to seizure onset lite rality, but al a lower statistical level (P < 0.01). Presentation of W ada memory stimuli earlier during hemispheric aesthesia yields results that are more sensitive to lateralized temporal lobe seizure onset th an does presentation of items later during the procedure. (C) 1997 Els evier Science B.V.