Is this the real life? Is this just fantasy? Neural correlates of perceptual reality monitoring

Summary

Visual experience can either be triggered externally, by light entering our eyes during perception, or internally, during mental imagery. Perception and imagery rely on similar neural mechanisms; however, we generally do not mistake our mental imagery for reality. Here I propose to investigate the neural mechanisms responsible for this “reality monitoring” by combining insights from metacognition and visual neuroscience. Specifically, I propose that this function is supported by an evaluation of evidence from specific layers of visual cortex by frontal decision areas. I will test this using a novel experimental paradigm in combination with cutting-edge neuroimaging techniques. I will first investigate the decision process by determining whether frontal cortex carries information about the attributed source (real or imagined) of a visual experience. Then, I will test whether visual cortex could provide this evidence by determining whether layer-specific activation dissociates externally from internally triggered visual experience. Finally, I will investigate how this information is used for source attribution by characterizing the connectivity between visual and frontal areas during perceptual reality monitoring. This research will improve the understanding of the fundamentals of visual experience and will have important implications for perceptual misattributions such as hallucinations.

Details

Project number

019.192SG.003

Main applicant

N. Dijkstra MSc

Affiliated with

Radboud Universiteit Nijmegen

Duration

01/03/2020 to 01/02/2022