Criterion-based validity of an intracarotid amobarbital recognition-memoryprotocol

Purpose: We tested whether the behavioral components of an Intracarotid Amo barbital Protocol (IAP) had criterion validity. It was hypothesized that a recognition-memory test designed for intracarotid injections and used to pr edict the risk of global amnesia before an elective temporal lobectomy shou ld also identify persons who are severely amnesic due to other neurologic c auses. Divergent validity predicts that speech tasks would be unaffected by amnesia. Test-retest reliability also was measured. Methods: Fifteen persons with severe amnesia were administered four alterna te forms of a yes/no recognition-memory protocol and a speech protocol. No drug injection occurred. Standardized neuropsychological tests were used to divide the amnesic group into those with Global Amnesia (i.e., retain no o ngoing memories), Severe Amnesia (i.e., memory impaired), and Amnesia Plus (severe amnesia plus other neuropsychologic deficits). Results: Two persons with Global Amnesia obtained scores at or below chance (i.e., failed) on the memory protocol. Unexpectedly, 12 of 13 severely amn esic persons obtained near-perfect memory scores. Amnesia had no impact on the speech protocol. Pass/Fail outcomes were highly correlated across all f our sets. Conclusions: A four-item IAP memory protocol showed good reliability and cr iterion validity in identifying the rare condition of Global Amnesia, but i t was insensitive to other disabling, severe amnesic disorders. This IAP me mory protocol might have validity in predicting a postsurgical Global Amnes ic disorder, but it did not identify and therefore could not predict other more common severe amnesic disorders.