Research Reports - Reduced contribution of executive functions in impaired working memory performance in mild traumatic brain injury patients
Clin Neurol Neurosurg. 2013 Jan 29
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.