Natalya V. Morozova

This article discusses the connection of hemispheric control over audioverbal perception processes and such individual features as “leading hand” (right-handedness and lefthandedness). We present a literature review and description of our research to provide evidence of the complexity and ambiguity of this connection. The method of dichotic listening was used for diagnosing audioverbal perception lateralization. This method allows estimation of the right-ear coefficient (REC), the efficiency coefficient (EC), and the effectiveness ratio (ER) of different aspects of audioverbal perception. Our research involved 47 persons with a leading right hand (mean age, 29.04±9.97 years) and 32 persons with a leading left hand (mean age, 29.41±10.34 years). Different hypotheses about the mechanisms of hemispheric control over audioverbal and motor processes were assessed. The research showed that both the leftand right-handers’ audioverbal perception characteristics depended mainly on right-hemisphere activity. The most dynamic and sensitive index of the functioning of the two hemispheres during dichotic listening was the efficiency coefficient of stimuli reproduction through the left ear (EC of the left ear). It turns out that this index depends on the coincidence/noncoincidence of the leading hemispheres in speech and motor processes. The highest efficiency of audioverbal perception revealed itself in the left-handers with a leading left ear (the hemispheric-control coincidence), and the lowest efficiency was in the left-handers with a leading right ear (the hemispheric-control divergence). The right-handers were characterized by less variation in values, although the influence of the coincidence/noncoincidence of the leading hemispheres in speech and motor processes also revealed itself as a tendency. This consistent pattern points out the necessity for further research on asymmetries of the different modalities that takes into account their probable interaction. The results of our study comport with scientific data showing genotypic left-handers with subzero right-ear coefficient (REC) values to be more efficient than left-handed persons who display high REC values.