Using electrocorticography to investigate the role of neuronal oscillations in multisensory speech perception

• Applicant: Dr. Inga Maren Schepers
• Subject Area: Human Cognitive and Systems Neuroscience
• Term: from 2012 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 223108620

Speech is the most important form of human communication and speech perception is multisensory, with both a visual and an auditory component. The superior temporal sulcus (STS) is a critical brain hub for multisensory integration and seems to be of particular relevance for the integration of audio-visual speech. Most studies investigating the function of the STS for multisensory integration in humans have applied functional magnetic resonance imaging (fMRI). While these studies have contributed a lot to our understanding of the role of the STS for audio-visual speech integration, we know little about the neural mechanisms that subserve processing of multisensory speech in the human STS. Therefore, we propose to use a unique population of human subjects who are implanted with subdural intracranial electrodes for the treatment of epilepsy. These patients provide the opportunity to directly measure neural activity with a high temporal and spatial resolution using electrocorticography (eCog). The focus of the research project will be on the role of gamma oscillations for the integration of multisensory speech. Neuronal oscillations in the gamma range have been found to reflect neuronal spiking activity and may serve as a general mechanism of information processing. We will investigate how the reliability of the auditory and the visual speech signal respectively influence processing of the speech signal in the STS. Additionally, it will be investigated how the reliability will affect the interaction between the auditory cortex and STS as well as the interaction between the visual cortex and STS. This project will help to understand the neural basis of audio-visual speech perception, which, in the long run, might help us treat patients with language dysfunctions.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor Michael S. Beauchamp, Ph.D.