Please join Dr. Hesheng Liu, PhD, Harvard Medical School & Massachusetts General Hospital, for a presentation entitled “Robust Decoding of Visual Information From the Human Brain.” The lecture will take place on Tuesday, November 1, 2016 as part of the Research Lecture Series. All are welcome to attend. Please note: COPE credit will not be awarded for this lecture.
Please join us for a wine and cheese reception in Conference Room 1 following the lecture.
The difficulty of visual recognition stems from the need to achieve high selectivity while maintaining robustness to object transformations within hundreds of milliseconds. Here, we quantified at millisecond resolution the amount of visual information conveyed by intracranial field potentials from electrodes implanted in human subjects. We could decode object category information from the occipitotemporal cortex in single trials as early as 100 ms poststimulus. Decoding performance was robust to depth rotation and scale changes. In a follow-up study, we replicated the findings that representations of object categories appear in the occipitotemporal cortex at about 100 ms poststimulus. However, within the next 100 milliseconds, categorical representations also emerged in early visual cortex. Along with the refinement of the visual content, the reliability of neural representation improved substantially in both areas. These data may suggest that a crude object code is initially formed in the occipitotemporal cortex by integrating the bottom-up inputs, which is then rapidly refined to support accurate recognition, probably through recurrent interactions between the occipitotemporal cortex and early visual cortex.
Research Lecture Series
The Research Lecture Series invites recognized vision scientists to present their latest research. These presentations are followed by discussions and informal receptions, allowing the College community an opportunity to become better acquainted with researchers and projects in other laboratories. The Spring 2016 series focused on "Amblyopia Research: Basic Mechanism, Diagnosis, and Treatment."