The neurobehavioral correlates of affect perception as a function of verbal fluency classification

The Dichotic Emotional Words Tape developed by Bryden and MacCrae (1989) was used to assess cerebral asymmetry for propositional and nonpropositional speech as a function of verbal fluency. Forty-five right-handed subjects with normal auditory acuity for pure tones were assigned to a verbal fluency classification based on scores on the FAS test (Borkowski, Benton, & Spreen, 1967). After being assigned to a fluency category, subjects were instructed to listen for a word (bower, dower, power, or tower) or affective tone (happy, sad, angry, or neutral). The most important findings of this study were the main effects of fluency (higher, middle, and lower), stimulus type (word and affect), and focus or intention (focus left and focus right). Subjects higher in fluency exhibited significantly greater REA and LEA scores than subjects lower in fluency. For stimuli presented to the right ear, scores for words were significantly greater than scores for affect. However, for stimuli presented to the left ear, scores for affect were significantly greater than scores for words. Focus left instructions led to increases in LEA scores, while focus right instructions led to increases in REA scores. Directions for future research are discussed.