Different patterns of cerebral activation in genuine and malingered cognitive effort during performance on the Word Memory Test.
OBJECTIVE
The Word Memory Test (WMT) is a popular symptom validity test in which individuals are required to remember and recall semantically-related word pairs. Research shows successful WMT completion employs a wide neural network which is involved in tasks requiring high cognitive effort. The primary purpose of this study was to replicate earlier fMRI findings using a larger sample and extend previous findings by including male and female subjects. The second purpose was to investigate the neural networks involved during intentional malingering on the WMT.


METHODS
For all trials, a time-series ANCOVA design was implemented using SPM5 software.


METHODS
Ten subjects (five male and five female) underwent fMRI imaging while completing the WMT in full-effort and simulated poor effort conditions.


RESULTS
Full-effort trials found activation peaks in dorsolateral prefrontal cortex, superior parietal lobe, anterior cingulate, bilateral lingual cortices and anterior insula/frontal operculum, supporting earlier findings. Simulated poor effort trials had similar foci of activation, with additional peak strength in surrounding cortical regions identified previously as relevant to simulated malingering. No sex differences were observed in either condition.


CONCLUSIONS
These findings demonstrate the neural underpinnings of WMT performance in normal and simulated performance.
Larsen
James D
JD
Psychology Department, Brigham Young University, Provo, Utah 84602, USA.
Allen
Mark D
MD
Bigler
Erin D
ED
Goodrich-Hunsaker
Naomi J
NJ
Hopkins
Ramona O
RO
D000328:Adult; D000704:Analysis of Variance; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008306:Malingering / Q000175:diagnosis* / Q000523:psychology; D008568:Memory / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D009483:Neuropsychological Tests; D015203:Reproducibility of Results; D012660:Semantics; D055815:Young Adult