A Dichotic Listening Study of Differences in Cerebral Organization in Dextral and Sinistral Subjects

Abstract

The purpose of the present study was to compare immediate recall of paired dichotic presentation of CV-syllables in a dextral and a sinistral group when considering both gender, familial sinistrality, and hand-posture during writing. Forty subjects (20 dextrals and 20 sinistrals) were given 306 presentations of the six Swedish stop-consonants paired with the vowels a, i, and u in a dichotic-listening test. The results showed significant differences between the two groups with fewer consonant-errors observed for the right ear input in the dextral group, and fewer consonant-errors in the left ear input in the sinistral group. Thus, a REA was demonstrated for the dextral group, and a LEA was demonstrated for the sinistral group. The results were most clear-cut for the consonants whereas vowels yielded insignificant differences. It is concluded that the present design allows for the separation of left- and right-hemisphere language dominance for right- and left-handed subjects.