PARS TRIANGULARIS ASYMMETRY AND LANGUAGE DOMINANCE

The pars triangularis is a portion of Broca's area. The convolutions t hat form the inferior and caudal extent of the pars triangularis inclu de the anterior horizontal and anterior ascending rami of the sylvian fissure, respectively. To learn if there are anatomic asymmetries of t he pars triangularis, these convolutions were measured on volumetric m agnetic resonance imaging scans of 11 patients who had undergone selec tive hemispheric anesthesia (Wada testing) to determine hemispheric sp eech and language lateralization. Of the 10 patients with language lat eralized to the left hemisphere, 9 had a leftward asymmetry of the par s triangularis. The 1 patient with language lateralized to the right h emisphere had a significant rightward asymmetry of the pars triangular is, Our data suggest that asymmetries of the pars triangularis may be related to speech-language lateralization.