Some aspects of speech-sound processing lateralization are discussed. Hemispheric differences in the execution of the tasks are investigated depending on the type of reaction (vocal or manual), different sides of stimulation, type of stimuli, presented monaurally to different ears of normal subjects. The foregoing acoustic and language experience of the subjects is considered in connection with their ability to fulfill the experimental task. The data demonstrate that processing of "native " and "foreign" syllables has the tendency to be controlled by different hemispheres:"foreign" need mostly left cerebral mechanisms both for the mimicking and for the identification of stimuli, while "native" can involve both hemispheres. Individual background plays significant role in cerebral balance of speech processing.

Keywords: speech processing, lateralization, categorization