Executive memory dysfunctions following mild traumatic brain injury

Objectives: To explore the contribution of executive dysfunctions to mnemonic problems in adults with mild traumatic brain injury (MTBI). Design: Prospective quasiexperimental between-groups design. Participants: Ninety-nine persons with MTBI were compared to 90 control group participants matched for gender, age, and education. Setting: Two Canadian brain injury rehabilitation programs. Main Outcome Measure: California Verbal Learning Test. Results: Participants with MTBI showed a significant deficit in free recall on the California Verbal Learning Test but performed similarly to the comparison group on the recognition task. Furthermore, the participants with MTBI were less likely to use semantic clustering as a memorizing strategy and made more intrusion errors and false-positive errors on the recognition task. Conclusions: While the scores for the participants with MTBI are only slightly lower than the norm, they demonstrate that MTBI has a negative effect on mnemonic performance. The results are explained in terms of a deficit in registration/retrieval processes rather than a malfunction of the storage processes. This supports the initial hypothesis that executive dysfunctions are detrimental to the quality of mnemonic functions in patients with MTBI.