The project will examine how the human brain implements the short-term memory representations necessary for comprehending language. In particular, the proposed experiments will investigate how sustained increases in neural activity contribute to language understanding, by recording brain activity as adults comprehend structured sentences. In so doing, this work will speak to questions about the role of sustained neural activity in short-term memory in cognition more broadly, which is currently the subject of much debate in the field. The basic research proposed here will ultimately pave the way for a better understanding of the language deficits associated with working memory problems in neurocognitive disorders such as aphasia and schizophrenia, as well as providing more fine-grained neural measures for evaluating language comprehension abilities in populations undergoing first and second language acquisition. The project will also provide numerous training opportunities for students in a technical and highly interdisciplinary research area that draws upon the fields of linguistics, cognitive psychology, computational linguistics, and cognitive neuroscience.
A key methodological element of the current project is the use of multimodal neuroimaging, which integrates data from a range of techniques (electroencephalography, magnetoencephalography, and functional MRI) in order to precisely identify relevant neural activity both in time and in brain space. These techniques are used to evaluate prior proposals that sustained activity in several brain regions (left inferior frontal cortex and left posterior temporal cortex) is what allows humans to represent relations between different parts of a sentence during language comprehension. Critically, the project builds on foundational work from linguistics and computational linguistics to devise structured language materials that can effectively probe different hypotheses about these neural mechanisms.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.