Limits...
Long-term effects of mild traumatic brain injury on cognitive performance.

Dean PJ, Sterr A - Front Hum Neurosci (2013)

Bottom Line: Participants with mTBI and persistent PCS had significantly greater error rates on both the n-Back and PVSAT, at every difficulty level except 0-Back (used as a test of performance validity).These results suggest that the reduction in cognitive performance is not due to greater symptom report itself, but is associated to some extent with the initial injury.Furthermore, the results validate the utility of our participant grouping, and demonstrate its potential to reduce the variability observed in previous studies.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Surrey Guildford, UK.

ABSTRACT
Although a proportion of individuals report chronic cognitive difficulties after mild traumatic brain injury (mTBI), results from behavioral testing have been inconsistent. In fact, the variability inherent to the mTBI population may be masking subtle cognitive deficits. We hypothesized that this variability could be reduced by accounting for post-concussion syndrome (PCS) in the sample. Thirty-six participants with mTBI (>1 year post-injury) and 36 non-head injured controls performed information processing speed (Paced Visual Serial Addition Task, PVSAT) and working memory (n-Back) tasks. Both groups were split by PCS diagnosis (4 groups, all n = 18), with categorization of controls based on symptom report. Participants with mTBI and persistent PCS had significantly greater error rates on both the n-Back and PVSAT, at every difficulty level except 0-Back (used as a test of performance validity). There was no difference between any of the other groups. Therefore, a cognitive deficit can be observed in mTBI participants, even 1 year after injury. Correlations between cognitive performance and symptoms were only observed for mTBI participants, with worse performance correlating with lower sleep quality, in addition to a medium effect size association (falling short of statistical significance) with higher PCS symptoms, post-traumatic stress disorder (PTSD), and anxiety. These results suggest that the reduction in cognitive performance is not due to greater symptom report itself, but is associated to some extent with the initial injury. Furthermore, the results validate the utility of our participant grouping, and demonstrate its potential to reduce the variability observed in previous studies.

No MeSH data available.


Related in: MedlinePlus

Error rate for (A): n-Back and (B): PVSAT tasks.*p < 0.05, **p < 0.01.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3569844&req=5

Figure 1: Error rate for (A): n-Back and (B): PVSAT tasks.*p < 0.05, **p < 0.01.

Mentions: Bonferroni-adjusted pairwise comparisons revealed that participants with mTBI and PCS produced significantly greater error rates than all other groups (see Figure 1) for the n-Back [mTBI − PCS: mean difference (MD) = 12.5, p < 0.001; Control + PCS: MD = 11.4, p = 0.001; Control − PCS: MD = 10.8, p = 0.002] and the PVSAT (mTBI − PCS: MD = 15.6, p < 0.001; Control + PCS: MD = 5.6, p < 0.001; Control − PCS: MD = 11.6, p = 0.005). All other comparisons were not statistically significant (all p = 1.0).


Long-term effects of mild traumatic brain injury on cognitive performance.

Dean PJ, Sterr A - Front Hum Neurosci (2013)

Error rate for (A): n-Back and (B): PVSAT tasks.*p < 0.05, **p < 0.01.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3569844&req=5

Figure 1: Error rate for (A): n-Back and (B): PVSAT tasks.*p < 0.05, **p < 0.01.
Mentions: Bonferroni-adjusted pairwise comparisons revealed that participants with mTBI and PCS produced significantly greater error rates than all other groups (see Figure 1) for the n-Back [mTBI − PCS: mean difference (MD) = 12.5, p < 0.001; Control + PCS: MD = 11.4, p = 0.001; Control − PCS: MD = 10.8, p = 0.002] and the PVSAT (mTBI − PCS: MD = 15.6, p < 0.001; Control + PCS: MD = 5.6, p < 0.001; Control − PCS: MD = 11.6, p = 0.005). All other comparisons were not statistically significant (all p = 1.0).

Bottom Line: Participants with mTBI and persistent PCS had significantly greater error rates on both the n-Back and PVSAT, at every difficulty level except 0-Back (used as a test of performance validity).These results suggest that the reduction in cognitive performance is not due to greater symptom report itself, but is associated to some extent with the initial injury.Furthermore, the results validate the utility of our participant grouping, and demonstrate its potential to reduce the variability observed in previous studies.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Surrey Guildford, UK.

ABSTRACT
Although a proportion of individuals report chronic cognitive difficulties after mild traumatic brain injury (mTBI), results from behavioral testing have been inconsistent. In fact, the variability inherent to the mTBI population may be masking subtle cognitive deficits. We hypothesized that this variability could be reduced by accounting for post-concussion syndrome (PCS) in the sample. Thirty-six participants with mTBI (>1 year post-injury) and 36 non-head injured controls performed information processing speed (Paced Visual Serial Addition Task, PVSAT) and working memory (n-Back) tasks. Both groups were split by PCS diagnosis (4 groups, all n = 18), with categorization of controls based on symptom report. Participants with mTBI and persistent PCS had significantly greater error rates on both the n-Back and PVSAT, at every difficulty level except 0-Back (used as a test of performance validity). There was no difference between any of the other groups. Therefore, a cognitive deficit can be observed in mTBI participants, even 1 year after injury. Correlations between cognitive performance and symptoms were only observed for mTBI participants, with worse performance correlating with lower sleep quality, in addition to a medium effect size association (falling short of statistical significance) with higher PCS symptoms, post-traumatic stress disorder (PTSD), and anxiety. These results suggest that the reduction in cognitive performance is not due to greater symptom report itself, but is associated to some extent with the initial injury. Furthermore, the results validate the utility of our participant grouping, and demonstrate its potential to reduce the variability observed in previous studies.

No MeSH data available.


Related in: MedlinePlus