Verbal Learning Strategy Following Mild Traumatic Brain Injury

Abstract

That learning and memory deficits persist many years following mild traumatic brain injury (mTBI) is controversial due to inconsistent objective evidence supporting subjective complaints. Our prior work demonstrated significant reductions in performance on the initial trial of a verbal learning task and overall slower rate of learning in well-motivated mTBI participants relative to demographically matched controls. In our previous work, we speculated that differences in strategy use could explain the differences in rate of learning. The current study serves to test this hypothesis by examining strategy use on the California Verbal Learning Test-Second Edition. Our present findings support the primary hypothesis that mTBI participants under-utilize semantic clustering strategies during list-learning relative to control participants. Despite achieving comparable total learning scores, we posit that the persisting learning and memory difficulties reported by some mTBI patients may be related to reduced usage of efficient internally driven strategies that facilitate learning. Given that strategy training has demonstrated improvements in learning and memory in educational and occupational settings, we offer that these findings have translational value in offering an additional approach in remediation of learning and memory complaints reported by some following mTBI.

Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans

“…Additionally, it is possible that the use of more specialized neuropsychological tests [or subsections of such tests, see Ref. (12, 13)] may have identified and isolated more discrete cognitive deficits. Such detailed assessments may have provided measures of cognitive impairment that might have been more associated with the biological measures of WM integrity.…”

“…Moreover, the authors stipulate that the magnitude of mTBI-related effects within each cognitive domain remains unclear as the respective effect sizes for “cognitive deficits” appear especially heterogeneous across meta-analyses (i.e., d  = −0.11 to 0.72) and that these higher order functions appear most susceptible to multiple mTBI [ d  = 0.24 (11)]. Recent reports also suggest that mTBI patients may, in fact, experience subtle cognitive deficits that reflect diminished initial acquisition of novel information (12, 13). Specifically, mTBI patients demonstrated statistically significant deficits in performance on the first trial of the California Verbal Learning Task, whereas there were no impairments on total learning or memory composite variables (12).…”

Reaffirmed Limitations of Meta-Analytic Methods in the Study of Mild Traumatic Brain Injury: A Response to Rohling et al.

“…A perfect example is a recent study from Geary and colleagues, who show that traditional mean and standard deviation measures of verbal memory, based on California Verbal Learning Test (CVLT) performance, were non-significant and therefore conventional analyses were insufficient in detecting any mTBI effects (Geary et al, 2011). In contrast their study revealed significant differences when methods that tapped different strategies of verbal learning were used; concluding that, ''Despite achieving comparable total learning scores .…”

“…We believe there is little argument with the above statement-the majority of mTBI patients over time enjoy a full functional return to their pre-injury baseline and their recovery follows a quick and rather benign course. However, some mTBI patients do experience persisting neurocognitive and neurobehavioral deficits and symptoms (Risdall & Menon, 2011), even after controlling for such factors as depression and potential response bias (Geary, Kraus, Rubin, Pliskin, & Little, 2011;Konrad et al, 2010). If return to baseline level of function is the norm in mTBI, and this recovery occurs within hours to days or within a few weeks, repeat neuropsychological studies that track mTBI outcome will evidence fewer findings over time that indicate any cognitive impairment.…”

Consolidation deficits in traumatic brain injury: The core and residual verbal memory defect

“…Similarly, deficits in learning strategies, such as impaired semantic organization, have been demonstrated (Carlesimo, Sabbadini, Loasses, & Caltagirone, 1997;Crosson et al, 1988;Geary, Kraus, Rubin, Pliskin, & Little, 2011;Goldstein, Levin, & Boake, 1989;Levin & Goldstein, 1986) and generally interpreted as indicating impaired encoding. However, an alternative explanation is that these organizational difficulties reflect executive dysfunction, rather than a memory encoding deficit.…”