Activation of the prefrontal cortex during the wisconsin card sorting test (Keio Version) as measured by two-channel near-infrared spectroscopy in patients with traumatic brain injury.

To investigate brain activation in the prefrontal cortex (PFC) during the Wisconsin Card Sorting Test (Keio Version) (KWCST), we examined changes in total hemoglobin volume (THV) in 8 patients with traumatic brain injury (TBI) and 20 healthy control subjects using two-channel near-infrared spectroscopy. As a result, average THV in the right PFC during KWCST in TBI patients (-0.131 +/- 0.127) was significantly lower than in control subjects (0.016 +/- 0.135) (2 x 3 ANOVA; p < 0.05). These results demonstrated that the TBI patients had lower circulation of hemoglobin in the right PFC during the KWCST than the control subjects.