Speaker: MICHAEL BONE, Psychology, University of Toronto
Title: Feature-specific neural reactivation during visual recollection
Ebbinghaus Empire Series 2018-2019
Video Recording of Talk
Abstract: When recalling a visual memory, the various features that constituted the original experience are recreated, to a limited extent, within the mind's eye. There is now strong evidence that the pattern of neural activity that occurred during the original experience is also recreated during recollection (neural reactivation), and that the degree of reactivation is correlated with the subjective vividness of the memory. To refine our understanding of this phenomenon, there have been recent attempts to identify neural reactivation associated with specific features (e.g. low-level visual features vs. semantic features). Unfortunately, these attempts have met with limited success due to the inherent correlations between features. We present a novel method, feature-specific informational connectivity (FSIC), to address this issue, and provide simulation evidence validating the approach. By applying this method to fMRI data collected while participants performed a naturalistic visual recollection task, we show that neural reactivation associated with low-level visual features (e.g. edges), high-level visual features (e.g. facial features), and semantic features (e.g. "terrier") occur throughout the dorsal and ventral visual streams and extend into the frontal cortex. Moreover, we show that neural reactivation associated with both low- and high-level visual features correlate with the vividness of the memory. In addition to demonstrating the utility of FSIC, these findings resolve the relative contributions of low- and high-level features to the vividness of visual memories, clarify the role of the frontal cortex during recollection, and challenge a strict interpretation the posterior-to-anterior visual hierarchy.
For further information please contact Amy Finn (email@example.com) or Michael Mack at firstname.lastname@example.org.
If you require an accommodation due to a disability, please contact the event coordinator OR email email@example.com five days prior to the event. We will work with you to make appropriate arrangements.