Research Reports - Reduced contribution of executive functions in impaired working memory performance in mild traumatic brain injury patients
Clin Neurol Neurosurg. 2013 Aug;115(8):1326-32
Kumar S, Rao SL, Chandramouli BA, Pillai S
AIM: Mild traumatic brain injury (MTBI) is associated with often selective
impairment of both working memory (WM) and the executive functions (EFs).
Research indicates that one of the commonest deficits present in MTBI patients
falls in the domain of WM. We aimed to investigate the role of EFs in WM
impairment following MTBI.
METHODS: Performance on the tests of EFs and the verbal and visuo-spatial WM of
30 consecutive MTBI patients were compared with age/education/IQ matched 30
normal healthy control participants. Correlation between EFs and WM was studied
separately for the MTBI and the control group.
RESULTS: The MTBI and control group were tested on a range of EF tests and WM.
The MTBI group was demonstrated impairment on verbal and visuo-spatial WM and
category fluency tests only. Furthermore, the MTBI group had fewer significant
correlations between the WM and EFs (5 out of 54 possible correlations) than in
the control group (13 out of 54 possible correlations).
CONCLUSIONS: We suggest that MTBI may lead to WM deficits as the contribution of
executive processes to support the WM is diminished following MTBI. Such an
understanding of the poor WM performance in MTBI patients will be helpful when
planning appropriate strategies for cognitive rehabilitation.