Research Reports - Retrieval practice improves memory in survivors of severe traumatic brain injury
Arch Phys Med Rehabil. 2013 Nov 11
Sumowski JF, Coyne J, Cohen A, Deluca J
OBJECTIVE: To investigate if retrieval practice [RP] improves delayed recall
after short and long delays in survivors of severe traumatic brain injury (TBI),
relative to massed restudy [MR] and spaced restudy [SR].
DESIGN: 3(learning condition: MR, SR, RP) X 2(delayed recall: 30 minutes, 1 week)
within-subjects experiment SETTING: non-profit medical rehabilitation research
PARTICIPANTS: Ten memory-impaired (<5th percentile) survivors of severe TBI
INTERVENTION: During RP, patients are quizzed on to-be-learned information
shortly after it is presented, such that patients practice retrieval. MR consists
of repeated restudy (i.e., cramming). SR consists of restudy trials separated in
time (i.e., distributed learning).
MAIN OUTCOME MEASURE(S): Forty-eight verbal paired associates (VPAs) were equally
divided across three learning conditions (16 per condition). Delayed recall for
half of VPAs was assessed after 30 minutes (8 per condition), and half after one
week (8 per condition).
RESULTS: There was a very large effect of learning condition after the short
delay (p<.001; η2=.72), with much better recall of VPAs studied through RP
(46.3%) relative to MR (12.5%) and SR (15.0%). This large effect of learning
condition remained after the long delay (p=.001; η2=.56), as patients recalled
11.3% of VPAs studied through RP, but nothing through MR (0.0%) and only 1.3%
through SR. That is, RP was essentially the only learning condition to result in
successful recall after one week, with most patients recalling at least one VPA.
CONCLUSIONS: The robust effect of RP among TBI survivors with severe memory
impairment engenders confidence that this strategy would work outside the
laboratory to improve memory in real-life settings. Future randomized controlled
trials of RP training are needed.