Motivation effects in a dichotic listening task as evident from functionalmagnetic resonance imaging in human subjects

The present study addresses the effect of motivation on cerebral activity u sing functional magnetic resonance imaging. Five healthy volunteers perform ed a dichotic listening task in two sets of three trials during which high or low levels of achievement motivation were introduced. They were told tha t the first set would be used for calculation of intellectual capacity (hig h achievement motivation) and the second set for scanner calibration (neutr al motivation). in three volunteers, high compared with neutral motivation produced activation in the right prefrontal cortex and the dorsal cingulate . We conclude that motivational effects may lead to significant activations and should be controlled in future cognitive imaging studies. We present p reliminary evidence that right prefrontal and dorsal cingulate regions migh t be involved in motivational processes. (C) 1999 Published by Elsevier Sci ence Ltd. All rights reserved.