title: Visual Population Receptive Fields in People with Schizophrenia Have Reduced Inhibitory Surrounds.
abstract: People with schizophrenia (SZ) experience abnormal visual perception on a range of visual tasks, which have been linked to abnormal synaptic transmission and an imbalance between cortical excitation and inhibition. However, differences in the underlying architecture of visual cortex neurons, which might explain these visual anomalies, have yet to be reportedin vivoHere, we probed the neural basis of these deficits using fMRI and population receptive field (pRF) mapping to infer properties of visually responsive neurons in people with SZ. We employed a difference-of-Gaussian model to capture the center-surround configuration of the pRF, providing critical information about the spatial scale of the pRFs inhibitory surround. Our analysis reveals that SZ is associated with reduced pRF size in early retinotopic visual cortex, as well as a reduction in size and depth of the inhibitory surround in V1, V2, and V4. We consider how reduced inhibition might explain the diverse range of visual deficits reported in SZ.SIGNIFICANCE STATEMENTPeople with schizophrenia (SZ) experience abnormal perception on a range of visual tasks, which has been linked to abnormal synaptic transmission and an imbalance between cortical excitation/inhibition. However, associated differences in the functional architecture of visual cortex neurons have yet to be reportedin vivoWe used fMRI and population receptive field (pRF) mapping to demonstrate that the fine-grained functional architecture of visual cortex in people with SZ differs from unaffected controls. SZ is associated with reduced pRF size in early retinotopic visual cortex largely due to reduced inhibitory surrounds. An imbalance between cortical excitation and inhibition could drive such a change in the center-surround pRF configuration and ultimately explain the range of visual deficits experienced in SZ.
authors.affiliation: Institute of Ophthalmology, e.anderson@ucl.ac.uk.|Institute of Cognitive Neuroscience.|Wellcome Trust Centre for Neuroimaging, and.
authors.forename: Elaine J
authors.initials: EJ
authors.lastname: Anderson
authors.affiliation: Institute of Ophthalmology.
authors.forename: Marc S
authors.initials: MS
authors.lastname: Tibber
authors.affiliation: Institute of Cognitive Neuroscience.|Experimental Psychology, University College London, London, United Kingdom.
authors.forename: D Sam
authors.initials: DS
authors.lastname: Schwarzkopf
authors.affiliation: Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.|South London and Maudsley National Health Service Foundation Trust, London, United Kingdom.
authors.forename: Sukhwinder S
authors.initials: SS
authors.lastname: Shergill
authors.affiliation: Clozapine Clinic, Cambridgeshire and Peterborough National Health Service Foundation Trust, and.|Department of Psychiatry, Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom, and.
authors.forename: Emilio
authors.initials: E
authors.lastname: Fernandez-Egea
authors.affiliation: Institute of Cognitive Neuroscience.|Wellcome Trust Centre for Neuroimaging, and.
authors.forename: Geraint
authors.identifier: 0000-0002-9623-7007
authors.initials: G
authors.lastname: Rees
authors.affiliation: Institute of Ophthalmology.|School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand.
authors.forename: Steven C
authors.identifier: 0000-0002-3548-9104
authors.initials: SC
authors.lastname: Dakin
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009433:Neural Inhibition / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods*; D012559:Schizophrenia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014793:Visual Cortex / Q000000981:diagnostic imaging / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*
keywords: fMRI; pRF; perception; schizophrenia; surround suppression; visual cortex