VERBAL fluency is known to be associated with activity in the left prefrontal cortex. Recent positron emission tomography (PET) results confirmed this finding. In the present study, high resolution functional magnetic resonance imaging (fMRI) was used to further localize activity in the prefrontal cortex related to verbal fluency. Activation was observed in three behavioral tasks: (1) Repeat - subjects repeated words, (2) Opposite - subjects produced the antonym of words, and (3) Generate - subjects generated words beginning with a given letter. When comparing Generate with both Repeat and Opposite, we observed small areas of activation in the left inferior frontal gyrus and anterior cingulate, similar to the centers of mass reported using PET. We also found additional activation around the superior frontal sulcus.
1Department of Psychology, Box 208250, Yale University, New Haven, CT 06520, USA
2Department of Chemistry, Box 208250, Yale University, New Haven, CT 06520, USA
3Department of Surgery, Box 208250, Yale University, New Haven, CT 06520, USA
4Department of Molecular Biophysics and Biochemistry, Box 208250, Yale University, New Haven, CT 06520, USA
5Present address: Department of Biochemistry, Oxford University, Oxford, UK
6Corresponding Author: Elizabeth A. Phelps.
ACKNOWLEDGEMENTS: This work was supported by grant DK34576 from the National Institute of Health, Bethesda, MD to RGS. The authors wish to thank T. Nixon for the maintenance and improvement of the spectrometer, and Dr D.L. Rothman for his helpful comments.
Received 30 July 1996; accepted 17 October 1996