ABC Seminar: Studying feedforward and feedback influences in the human brain

Welcome to our ABC Seminars! This seminar series is open for everyone. The talk will take place in Otakaari 1, U141 (U3). After the talks, coffee and pulla will be served.

The event will be also streamed via Zoom at: https://aalto.zoom.us/j/67444945844

Title: 

Studying feedforward and feedback influences in the human brain.

Abstract: 

Hierarchical organization among cortical areas is characterized by specific laminar profiles of inter-area connectivity. Advances in non-invasive functional neuroimaging have made it possible to infer information about feedforward- and feedback-type inputs to a cortical area, even in cases in which the spatial resolution as such may not be high enough to directly resolve laminar activation patterns. We combined magnetoencephalography (MEG) source estimation with biophysical computational modeling to investigate cross-sensory visual evoked activity in the human auditory cortex. The results provided evidence of visual evoked activity in the auditory cortex being driven by feedback-type input, consistent with previous reports in nonhuman primates. This study illustrates how the dynamic patterns of estimated MEG source activity can be interpreted in the context of hierarchical organization among cortical areas in the human brain.

Bio: 

Seppo Ahlfors, Ph.D., is Director of MEG Technology at the David Cohen MEG Laboratory of the Athinoula A. Martinos Center for Biomedical Imaging, and Associate Professor at the Department of Radiology at Massachusetts General Hospital and Harvard Medical School. He obtained a doctorate in Physics and Biomedical Engineering from Helsinki University of Technology 1994. After postdoctoral training at Albert Einstein College of Medicine in New Tork, he joined the faculty at MGH. His research primarily focuses on the analysis and interpretation of magnetoencephalography (MEG) data and multimodal human neuroimaging.