The subject matter of this research project are psycholinguistic and neurolinguistic mechanisms of language acquisition, language processing in younger and older adults, and language impairment in people with neurological disorders. The project involved diverse populations of language users (healthy monolinguals and bilinguals of different age, as well as patients with language disorders), which made it possible to study individual variability and universal mechanisms involved in language processing and to extend the understanding of the neural bases of language processing.
The objective is to identify individual and general mechanisms of normal language acquisition and language processing, as well as to investigate the nature of language impairment in people with brain disorders. Our specific research tasks were to investigate the mechanisms of typical and atypical language acquisition in children; to study psycholinguistic mechanisms in younger and older healthy monolingual adults; to identify the neural basis of language impairments in patients with brain disorders; and to identify language-specific mechanisms in healthy bilinguals.
The employed methods include cutting-edge methods of experimental linguistics and neuroscience: behavioral techniques measuring accuracy and reaction time (such as lexical decision, picture naming, self-paced reading, elicited production, etc.), eye-tracking, structural neuroimaging (including voxel-based lesion-symptom mapping and diffusion tensor tractography), functional magnetic resonance imaging (task-based and resting-state), direct electrical stimulation during awake neurosurgery.
Empirical base of research involves a set of psycholinguistic and neurolinguistic experiments. Participants belonged to diverse populations of different age, neurological and linguistic status: healthy children, healthy younger and older monolinguals, healthy bilinguals, patients with post-stroke aphasia, patients with brain tumors, and patients with epilepsy. Participants included native speakers of Russian, learners of Russian as L2, along with native speakers of English, Bashkir, and Japanese. Population and linguistic diversity allowed us to tackle the universal mechanisms of human language processing.
The results of this research project involve new empirical evidence about language functioning at different levels (phonological, lexical, grammatical and discourse) in children, neurologically healthy adults, and patients with brain damage. The findings have been published in eight original articles in English in high-impact international peer-reviewed journals, as well as presented at various international conferences.
Recommendations on implementation of the results involve further use of our experimental methods and findings in both basic and applied studies of language processing. Our research findings can inform future empirical studies that aim to further specify psycholinguistic and neurolinguistic models of language acquisition, normal functioning, and impairment. In addition, our results can aid in development of new clinical tools for language assessment and therapy in clinical populations.