Two distinct feedback codes in V1 for ‘real’ and ‘imaginary’ internal experiences. Bergmann, J., Morgan, A. T., & Muckli, L. Technical Report Neuroscience, June, 2019.
Two distinct feedback codes in V1 for ‘real’ and ‘imaginary’ internal experiences [link]Paper  doi  abstract   bibtex   
Visual illusions and visual imagery are conscious sensory events that lack a corresponding physical input. But while everyday mental imagery feels distinct from incoming stimulus input, visual illusions, like hallucinations, are under limited volitional control and appear indistinguishable from physical reality. Illusions are thought to arise from lower-level processes within sensory cortices. In contrast, imagery involves a wide network of brain areas that recruit early visual cortices for the sensory representation of the imagined stimulus. Here, we combine laminar fMRI brain imaging with psychophysical methods and multivariate pattern analysis to investigate in human participants how seemingly ‘real’ and imaginary non-physical experiences are processed in primary visual cortex (V1). We find that the content of mental imagery is only decodable in deep layers, whereas illusory content is only decodable at superficial depths. This suggests that feedback to the different layers may serve distinct functions: low-level feedback to superficial layers might be responsible for shaping perception-like experiences, while deeplayer feedback might serve the formation of a more malleable ‘inner’ world, separate from ongoing perception.
@techreport{bergmann_two_2019,
	type = {preprint},
	title = {Two distinct feedback codes in {V1} for ‘real’ and ‘imaginary’ internal experiences},
	url = {http://biorxiv.org/lookup/doi/10.1101/664870},
	abstract = {Visual illusions and visual imagery are conscious sensory events that lack a corresponding physical input. But while everyday mental imagery feels distinct from incoming stimulus input, visual illusions, like hallucinations, are under limited volitional control and appear indistinguishable from physical reality. Illusions are thought to arise from lower-level processes within sensory cortices. In contrast, imagery involves a wide network of brain areas that recruit early visual cortices for the sensory representation of the imagined stimulus. Here, we combine laminar fMRI brain imaging with psychophysical methods and multivariate pattern analysis to investigate in human participants how seemingly ‘real’ and imaginary non-physical experiences are processed in primary visual cortex (V1). We find that the content of mental imagery is only decodable in deep layers, whereas illusory content is only decodable at superficial depths. This suggests that feedback to the different layers may serve distinct functions: low-level feedback to superficial layers might be responsible for shaping perception-like experiences, while deeplayer feedback might serve the formation of a more malleable ‘inner’ world, separate from ongoing perception.},
	language = {en},
	urldate = {2023-01-03},
	institution = {Neuroscience},
	author = {Bergmann, Johanna and Morgan, Andrew T. and Muckli, Lars},
	month = jun,
	year = {2019},
	doi = {10.1101/664870},
}

Downloads: 0