The ability to comprehend language is a hallmark of human intelligence. Although this ability seems to come effortlessly to neurologically normal adults, such ease belies a complex underlying network of neural processes. A major challenge in investigating the neural mechanisms of language comprehension is that people may not all process language in exactly the same way. People may vary substantially, for example, in the ease with which they can recognize words and in their abilities to hold in mind information about the preceding words and sentences. Given such individual differences, the mechanisms of language processing can be obscured if researchers adopt the common neuroimaging practice of averaging together brain activity from different people who have experienced the same stimuli (for example, the same word). With support from the National Science Foundation, Dr. Albert Kim and his colleague Dr. Akira Miyake will investigate the neural mechanisms of language comprehension with a focus on systematic differences between individuals. . Dr. Kim and Dr. Miyake will record brain electrical activity using electroencephalography (EEG) from the scalps of participants who are reading sentences, measuring event related potentials (ERPs) for each word in the sentences. They will incorporate recent advances in application of blind source separation (BSS) algorithm into this research to enable separation of fast brain electrical signals from different brain regions and enable characterization of individual differences in the neurobiology of language processing in ways that cannot be provided by fMRI based brain imaging.
Developmental disorders of language comprehension impede scholastic and professional success, and acquired language comprehension disorders, such as those following stroke, can be fundamentally debilitating. Thus, understanding the basic mechanisms of language processing is likely to be relevant to the diagnosis and treatment of disordered language. Because of the novelty of simultaneously measuring and comparing multiple measures of individual differences in language processes, this work has the potential to transform current research practices in the field. Dr. Kim and Dr. Miyake will maximize the broader impact of the work by organizing special journal issues in appropriate outlets and special workshops within national and international conferences. The goal of these special issues and workshops will be to assemble research in various areas in cognitive neuroscience (e.g., language, memory, attention, decision making) that illustrates the theoretical importance and viability of integrating individual differences analyses, neurocognitive theories, and modern analysis methods. Finally, because the proposed research involves multiple research methods and approaches, it will provide exceptionally rich training opportunities to the graduate students and undergraduate students who will be working on the project.
