COGNITIVE STIMULATION WITH THE WISCONSIN CARD SORTING TEST - FUNCTIONAL MR-IMAGING AT 1.5 T

PURPOSE: To determine whether functional magnetic resonance (MR) imagi ng can demonstrate a specific pattern of cerebral activation during co gnitive stimulation by using a high-level cognitive task such as the W isconsin Card Sorting Test. MATERIALS AND METHODS: Thirty-one healthy volunteers underwent functional MR imaging with a 1.5-T MR imager with a 1.5-T MR imager with a standard head coil (100/50 [repetition time msec/echo time msec], 230-mm field of view, 40 degrees flip angle, 256 x 256 matrix). For stimulation, a personal computer version of the Wi sconsin Card Sorting Test was used. Image analysis was done off-line, and cross-correlation coefficients between the stimulus function and t he signal intensity response were calculated on a pixel-by-pixel basis and overlaid onto the corresponding anatomic MR image for each volunt eer. RESULTS: Stimulation resulted in strongly frontal activation, whi ch included the mesial and the dorsolateral prefrontal cortexes, inter connected with Brodmann areas 44, 45, and 46. While activation was oft en bilateral, the largest area of activation was in the right hemisphe re. Activation also was found in the basal ganglia and the mesial thal amic nuclei. CONCLUSION: Functional MR imaging can demonstrate a speci fic pattern during activation with a cognitive task. Functional MR ima ging has promise for more precise anatomic and functional imaging stud ies of brain interaction than have other imaging modalities.