Spacing of repetitions improves learning and memory after moderate and severe TBI.

Extensive research has determined that new learning in healthy individuals is significantly improved when trials are distributed over time (spaced presentation) compared to consecutive learning trials (massed presentation). This phenomenon known as the "spacing effect" (SE) has been shown to enhance verbal and nonverbal learning in healthy adults of different ages and in different memory paradigms (e.g., recognition, recall, etc.). The purpose of this study was to examine whether learning in adults with moderate and severe traumatic brain injury (TBI) is improved using a spacing-of-repetitions procedure. Using a within-groups design, participants with TBI (n = 20) were presented a list of 115 words that were presented either once (single condition), twice consecutively (massed condition), or twice with 11 words between presentations (spaced condition). Participants were required to rank each word from 1 to 10 according to their familiarity with the word; they were not asked to "memorize" words for a later test. Word list learning was measured with a free recall test immediately following list presentation and with free recall and recognition tests after a 30-min delay. Participants recalled and recognized significantly more spaced words than massed words during this word list learning task. These results strongly indicate that the spacing of repetitions improves learning and memory in individuals who have sustained moderate to severe TBI. Implications for rehabilitation are discussed.

Comparison of remedial and compensatory interventions for adults with acquired brain injuries.

OBJECTIVE: To examine the effects of a compensatory intervention versus a remedial intervention for deficits in visual processing of adults with acquired brain injuries (ABI). SETTING: A cognitive rehabilitation program at a large comprehensive rehabilitation hospital in the New York City metropolitan area. PATIENTS: Thirty adults with ABI were matched according to severity of injury, gender, age, and time post-injury, and randomly assigned to the remedial or compensatory group. INTERVENTIONS: The remedial intervention consisted of four 45-minute sessions (once weekly) of participation in computer tasks without instruction in compensatory strategies. The compensatory intervention consisted of four 45-minute sessions of instruction in the use of three internal compensatory strategies, including verbalization, chunking, and pacing. MAIN OUTCOME MEASURES: Pretest/posttest measures included three functional computer tasks. Weekly measures included a computerized version of the Paced Auditory Serial Addition Task (PASAT) and two computerized matching tasks. RESULTS: Both groups exhibited statistically significant improvement of comparable degree on posttests and weekly measures. Further analysis revealed that 80% of both groups used compensatory strategies, regardless of intervention method. Those who used strategies demonstrated better performance than those who did not. CONCLUSION: The ability to use internal compensatory strategies may be a significant confound in research examining the effects of the various cognitive rehabilitation intervention methods.