2009 Volume 11 Issue 2 Pages 87-91
A functional magnetic resonance imaging study on visuo-spatial working memory task using sinusoidal luminance grating inferred to have little influence on verbal working memory was presented. Seven right-handed healthy male participants wearing a head mount display were scanned while performing two 2-back tasks using the different spatial frequency stimuli. As results, the accuracy of the task using low spatial frequency stimuli was significantly-higher than that of the task using high spatial frequency stimuli. Moreover, both tasks activated the neural network between the prefrontal cortex and the parietal cortex. The activated areas on the right hemisphere were larger than those on left hemisphere. The intensity level of the frontal cortex activation was also asymmetric. The high spatial frequency task activated the right hemisphere higher than the left hemisphere. On the contrary, the low spatial frequency task activated the left hemisphere higher than the other one. Moreover, the activation in the ventrolateral region of left prefrontal cortex during the low spatial frequency task was salient. The activation was found to be caused by the verbalization changing the low spatial stimuli into the numbers.
