2021 Volume 49 Issue 6 Pages 459-468
Although various executive functions are thought to be subserved by different regions in the prefrontal cortex, the changes in the cerebral blood flow during the performance of problem-solving tasks involving reasoning (Crack-the-Code tasks) have not yet been investigated. In the present study, 28 healthy adults were asked to perform a total of eight tasks in four blocks, and NIRS measurements were taken from the frontal region. The results showed that as the difficulty level increased, the percentage of correct answers decreased, and the number of movements, reaction time, total time, and evaluation time increased. In terms of cerebral hemodynamics, the level of oxy-Hb in the left DLPFC in the block with higher difficulty, and in the left and right mPFC in the latter half of the two tasks within this block, increased significantly. These results suggest that, with increasing task difficulty, a trial-and-error approach is reflected in the problem solving performance; that the left DLPFC is involved throughout the problem solving process; and that, in complex problem solving, the right mPFC region is involved in the processing of the both prefrontal cortex.
