RealOrImagined · Is this the real life? Is this just fantasy? Neural correlates of perceptual reality monitoring
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2021-09-01 → 2024-02-18
- EU contribution
- €212,934
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Is this the real life? Is this just fantasy? Neural correlates of perceptual reality monitoring
When walking down the street, we are bombarded with visual input. Different colours, shapes and textures are processed by our visual system to create the technicolour perception we experience every day. At the same time, while we are thinking about things that we will do later or things that we have already done, we experience a rapid stream of mental images. Mental imagery relies on similar neural mechanisms as visual perception. Imagining and perceiving the same stimulus is associated with similar patterns of neural activation throughout the visual system and similar connectivity between different brain areas. However, we do not generally confuse what is real with what is imagined. In this project, I aimed to investigate the neural mechanisms underlying this ability for “reality monitoring”. Given the large neural overlap between imagery and perception, how does the brain know whether what we see is real or imagined? Understanding how the brain keeps track of what is real and what is imagined will provide new perspectives on our understanding of disorders of reality monitoring. For example, in psychosis, the line between imagination and reality blurs, and patients might start believing that what they imagine is real. The objectives of the project were as follows: First, I planned to determine if the decision process that determines whether a current visual experience has an external or internal source is supported by the medial prefrontal cortex. Next, I planned to investigate whether the middle layer of the visual cortex could provide evidence for this source attribution. Finally, I aimed to investigate how source-relevant evidence was integrated in the brain over time.
Data: CORDIS, © European Union
Project objective
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.
Original text from CORDIS.
Participants
- UNIVERSITY COLLEGE LONDON · LondonCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union