Language lateralization in English-French bilinguals.

Forty English-French bilinguals divided into equal numbers of nonfluent and fluent subjects took part in a dichotic listening test involving both intralingual and interlingual conditions. No difference in lateralization was found between primary and secondary language in either condition. In the intralingual condition, however, fluent bilinguals showed a significantly lower right ear advantage than did their nonfluent counterparts. In the interlingual condition, French-dominant subjects were found to be more ambilateral than English-dominant subjects, while both groups tended to respond preferentially to French words. These results suggest that growing bilingual proficiency does increase left ear/right hemisphere participation, but in intralingual situations only. Moreover, when both languages are contrasted, French appears to be more salient than English.