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Whitford V, Byers N, O'Driscoll GA, Titone D. Eye movements and the perceptual span in disordered reading: A comparison of schizophrenia and dyslexia. Schizophr Res Cogn 2023; 34:100289. [PMID: 37435364 PMCID: PMC10331593 DOI: 10.1016/j.scog.2023.100289] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/16/2023] [Accepted: 06/20/2023] [Indexed: 07/13/2023]
Abstract
Increasing evidence of a common neurodevelopmental etiology between schizophrenia and developmental dyslexia suggests that neurocognitive functions, such as reading, may be similarly disrupted. However, direct comparisons of reading performance in these disorders have yet to be conducted. To address this gap in the literature, we employed a gaze-contingent moving window paradigm to examine sentence-level reading fluency and perceptual span (breadth of parafoveal processing) in adults with schizophrenia (dataset from Whitford et al., 2013) and psychiatrically healthy adults with dyslexia (newly collected dataset). We found that the schizophrenia and dyslexia groups exhibited similar reductions in sentence-level reading fluency (e.g., slower reading rates, more regressions) compared to matched controls. Similar reductions were also found for standardized language/reading and executive functioning measures. However, despite these reductions, the dyslexia group exhibited a larger perceptual span (greater parafoveal processing) than the schizophrenia group, potentially reflecting a disruption in normal foveal-parafoveal processing dynamics. Taken together, our findings suggest that reading and reading-related functions are largely similarly disrupted in schizophrenia and dyslexia, providing additional support for a common neurodevelopmental etiology.
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Affiliation(s)
- Veronica Whitford
- Department of Psychology, University of New Brunswick, 38 Dineen Drive, Fredericton, New Brunswick, E3B 5A3, Canada
| | - Narissa Byers
- Department of Psychology, University of New Brunswick, 38 Dineen Drive, Fredericton, New Brunswick, E3B 5A3, Canada
| | - Gillian A. O'Driscoll
- Department of Psychology, McGill University, 2001 Avenue McGill College, Montréal, Québec, H3A 1G1, Canada
- Department of Psychiatry, McGill University, 1003 Avenue des Pins Ouest, Montréal, Québec, H3A 1A1, Canada
- Douglas Mental Health University Institute, 6875 Boulevard LaSalle, Verdun, Québec, H4H 1R3, Canada
- Montreal Neurological Institute and Hospital, 3801 Rue University, Montréal, Québec, H3A 2B4, Canada
- Department of Neurology & Neurosurgery, McGill University, 1003 Avenue des Pins Ouest, Montréal, Québec, H3A 1A1, Canada
| | - Debra Titone
- Department of Psychology, McGill University, 2001 Avenue McGill College, Montréal, Québec, H3A 1G1, Canada
- Centre for Research on Brain, Language and Music, 3640 Rue de la Montagne, Montréal, Québec, H3G 2A8, Canada
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Keyvanfard F, Nasab AR, Nasiraei-Moghaddam A. Brain subnetworks most sensitive to alterations of functional connectivity in Schizophrenia: a data-driven approach. Front Neuroinform 2023; 17:1175886. [PMID: 37274751 PMCID: PMC10232974 DOI: 10.3389/fninf.2023.1175886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/24/2023] [Indexed: 06/06/2023] Open
Abstract
Functional connectivity (FC) of the brain changes in various brain disorders. Its complexity, however, makes it difficult to obtain a systematic understanding of these alterations, especially when they are found individually and through hypothesis-based methods. It would be easier if the variety of brain connectivity alterations is extracted through data-driven approaches and expressed as variation modules (subnetworks). In the present study, we modified a blind approach to determine inter-group brain variations at the network level and applied it specifically to schizophrenia (SZ) disorder. The analysis is based on the application of independent component analysis (ICA) over the subject's dimension of the FC matrices, obtained from resting-state functional magnetic resonance imaging (rs-fMRI). The dataset included 27 SZ people and 27 completely matched healthy controls (HC). This hypothesis-free approach led to the finding of three brain subnetworks significantly discriminating SZ from HC. The area associated with these subnetworks mostly covers regions in visual, ventral attention, and somatomotor areas, which are in line with previous studies. Moreover, from the graph perspective, significant differences were observed between SZ and HC for these subnetworks, while there was no significant difference when the same parameters (path length, network strength, global/local efficiency, and clustering coefficient) across the same limited data were calculated for the whole brain network. The increased sensitivity of those subnetworks to SZ-induced alterations of connectivity suggested whether an individual scoring method based on their connectivity values can be applied to classify subjects. A simple scoring classifier was then suggested based on two of these subnetworks and resulted in acceptable sensitivity and specificity with an area under the ROC curve of 77.5%. The third subnetwork was found to be a less specific building block (module) for describing SZ alterations. It projected a wider range of inter-individual variations and, therefore, had a lower chance to be considered as a SZ biomarker. These findings confirmed that investigating brain variations from a modular viewpoint can help to find subnetworks that are more sensitive to SZ-induced alterations. Altogether, our study results illustrated the developed method's ability to systematically find brain alterations caused by SZ disorder from a network perspective.
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Affiliation(s)
- Farzaneh Keyvanfard
- School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
| | - Alireza Rahimi Nasab
- Biomedical Engineering Department, Amirkabir University of Technology, Tehran, Iran
| | - Abbas Nasiraei-Moghaddam
- School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
- Biomedical Engineering Department, Amirkabir University of Technology, Tehran, Iran
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3
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Chrobak AA, Rybakowski JK, Abramowicz M, Perdziak M, Gryncewicz W, Dziuda S, Fafrowicz M, Czarnecki P, Soltys Z, Ceglarek A, Ober JK, Marek T, Dudek D, Siwek M. Vergence eye movements impairments in schizophrenia and bipolar disorder. J Psychiatr Res 2022; 156:379-389. [PMID: 36323140 DOI: 10.1016/j.jpsychires.2022.10.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 09/07/2022] [Accepted: 10/17/2022] [Indexed: 11/07/2022]
Abstract
One of the most evaluated eye tracking tasks in schizophrenia (SZ) and bipolar disorder (BD) are smooth pursuit eye movements. They rely on the maintenance of slowly moving object on the fovea. While most of the studies evaluated tracking of a target that moves in the fronto-parallel plane, only two assessed vergence eye movements (VEM), which relies on the pursuit of object that moves in depth. The aim of our study was to compare VEM performance in SZ and BD. We evaluated 28 SZ patients, 32 BD patients and 25 healthy controls (HC). Participants underwent thorough optometric examination before eye tracking task. VEM were measured with the use of infrared eye tracker and dedicated vergence stimuli generator. SZ patients showed higher mean break and recovery points of fusion and shorter correct tracking time than HC. BD individuals revealed tracking accuracy deficits and higher number of saccades than HC. Compared to BD, SZ patients showed decrease of maximal convergence and divergence. Moreover, they presented tracking accuracy deficits of non-dominant eye: altered eyes positioning error during convergence and divergence gain. Exploratory analysis revealed significant gender differences between groups in terms of binocular VEM parameters. In this study we have recognized pattern of eye movement disturbances differentiating abovementioned groups. SZ patients showed decreased vergence tracking range with shorter tracking time and impaired accuracy of non-dominant eye, while BD patients showed higher number of saccades with decreased tracking accuracy. Neuroimaging studies are necessary to identify neuronal underpinnings of VEM impairments in SZ and BD.
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Affiliation(s)
- Adrian Andrzej Chrobak
- Jagiellonian University Medical College, Department of Adult Psychiatry, Kopernika St. 21a, 31-501, Cracow, Poland
| | - Janusz Kazimierz Rybakowski
- Poznan University of Medical Sciences, Department of Adult Psychiatry, Szpitalna St. 27/33, 61-572, Poznań, Poland
| | - Maria Abramowicz
- Poznan University of Medical Sciences, Department of Adult Psychiatry, Szpitalna St. 27/33, 61-572, Poznań, Poland
| | - Maciej Perdziak
- Poznan University of Medical Sciences, Department of Optometry, Chair of Ophthalmology and Optometry, Rokietnicka St. 5D, 60-806, Poznań, Poland
| | - Wojciech Gryncewicz
- Polish Academy of Sciences, Nałęcz Institute of Biocybernetics and Biomedical Engineering, Księcia Trojdena St. 4, 02-109, Warsaw, Poland
| | - Sebastian Dziuda
- Poznan University of Medical Sciences, Department of Adult Psychiatry, Szpitalna St. 27/33, 61-572, Poznań, Poland
| | - Magdalena Fafrowicz
- Jagiellonian University, Institute of Applied Psychology, Department of Cognitive Neuroscience and Neuroergonomics, Łojasiewicza St. 4, 30-348, Cracow, Poland
| | - Paweł Czarnecki
- Polish Academy of Sciences, Nałęcz Institute of Biocybernetics and Biomedical Engineering, Księcia Trojdena St. 4, 02-109, Warsaw, Poland
| | - Zbigniew Soltys
- Jagiellonian University, Institute of Zoology and Biomedical Research, Laboratory of Experimental Neuropathology, Gronostajowa 9, 30-387, Cracow, Poland
| | - Anna Ceglarek
- Jagiellonian University, Institute of Applied Psychology, Department of Cognitive Neuroscience and Neuroergonomics, Łojasiewicza St. 4, 30-348, Cracow, Poland
| | - Jan Krzysztof Ober
- Poznan University of Medical Sciences, Department of Optometry, Chair of Ophthalmology and Optometry, Rokietnicka St. 5D, 60-806, Poznań, Poland
| | - Tadeusz Marek
- Jagiellonian University, Institute of Applied Psychology, Department of Cognitive Neuroscience and Neuroergonomics, Łojasiewicza St. 4, 30-348, Cracow, Poland
| | - Dominika Dudek
- Jagiellonian University Medical College, Department of Adult Psychiatry, Kopernika St. 21a, 31-501, Cracow, Poland
| | - Marcin Siwek
- Jagiellonian University Medical College, Department of Affective Disorders, Kopernika St. 21a, 31-501, Cracow, Poland.
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Wolf A, Ueda K, Hirano Y. Recent updates of eye movement abnormalities in patients with schizophrenia: A scoping review. Psychiatry Clin Neurosci 2021; 75:82-100. [PMID: 33314465 PMCID: PMC7986125 DOI: 10.1111/pcn.13188] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/27/2020] [Accepted: 12/09/2020] [Indexed: 12/15/2022]
Abstract
AIM Although eye-tracking technology expands beyond capturing eye data just for the sole purpose of ensuring participants maintain their gaze at the presented fixation cross, gaze technology remains of less importance in clinical research. Recently, impairments in visual information encoding processes indexed by novel gaze metrics have been frequently reported in patients with schizophrenia. This work undertakes a scoping review of research on saccadic dysfunctions and exploratory eye movement deficits among patients with schizophrenia. It gathers promising pieces of evidence of eye movement abnormalities in attention-demanding tasks on the schizophrenia spectrum that have mounted in recent years and their outcomes as potential biological markers. METHODS The protocol was drafted based on PRISMA for scoping review guidelines. Electronic databases were systematically searched to identify articles published between 2010 and 2020 that examined visual processing in patients with schizophrenia and reported eye movement characteristics as potential biomarkers for this mental illness. RESULTS The use of modern eye-tracking instrumentation has been reported by numerous neuroscientific studies to successfully and non-invasively improve the detection of visual information processing impairments among the screened population at risk of and identified with schizophrenia. CONCLUSIONS Eye-tracking technology has the potential to contribute to the process of early intervention and more apparent separation of the diagnostic entities, being put together by the syndrome-based approach to the diagnosis of schizophrenia. However, context-processing paradigms should be conducted and reported in equally accessible publications to build comprehensive models.
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Affiliation(s)
- Alexandra Wolf
- International Research Fellow of Japan Society for the Promotion of Science, Fukuoka, Japan.,Department of Human Science, Research Center for Applied Perceptual Science, Kyushu University, Fukuoka, Japan
| | - Kazuo Ueda
- Department of Human Science, Research Center for Applied Perceptual Science, Kyushu University, Fukuoka, Japan
| | - Yoji Hirano
- Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Yoon JH, Maddock RJ, Cui ED, Minzenberg MJ, Niendam TA, Lesh T, Solomon M, Ragland JD, Carter C. Reduced in vivo visual cortex GABA in schizophrenia, a replication in a recent onset sample. Schizophr Res 2020; 215:217-222. [PMID: 31704157 PMCID: PMC7035988 DOI: 10.1016/j.schres.2019.10.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 09/07/2019] [Accepted: 10/09/2019] [Indexed: 12/20/2022]
Abstract
The GABA deficit hypothesis remains one of the most compelling explanations for the information processing impairments in schizophrenia. However, much of the supportive evidence has been derived from post-mortem studies, whereas in vivo studies have largely yielded inconsistent results. We undertook this single voxel proton magnetic resonance (MRS) GABA study to test in a sample of recent onset patients the replicability of our prior finding of reduced early visual cortex GABA in schizophrenia. We also examined the possibility that antipsychotics could represent a significant confound by studying a small subsample of antipsychotic naïve subjects. 23 adults with recent onset schizophrenia and a demographically matched sample of 31 healthy control subjects underwent MRS using a MEGA PRESS sequence on a 3T MR scanner to measure GABA concentration in early visual cortex. To control for in-scanner head movement confounding the results, we quantified the amount of head movement during GABA scans to identify and exclude from analysis scans with excessive movement. Patients demonstrated significantly reduced GABA levels compared to control subjects, p = 0.029. GABA levels did not differ significantly between patients who were antipsychotic naïve (n = 7) and patients treated with antipsychotics. This replication in a recent onset sample suggest that diminished GABA in the visual cortex is a reliable finding, present in early phase of illness and not confounded by illness chronicity.
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Affiliation(s)
- Jong H. Yoon
- Palo Alto VA Healthcare System, 3801 Miranda Avenue, Palo Alto, CA 94304, USA,Stanford University, 401 Quarry Road, Palo Alto, CA 94301, USA
| | | | - Edward DongBo Cui
- Palo Alto VA Healthcare System, 3801 Miranda Avenue, Palo Alto, CA 94304, USA,Stanford University, 401 Quarry Road, Palo Alto, CA 94301, USA
| | - Michael J. Minzenberg
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA 90024, USA
| | - Tara A. Niendam
- University of California, Davis, 4701 X St, Sacramento, CA 95817, USA
| | - Tyler Lesh
- University of California, Davis, 4701 X St, Sacramento, CA 95817, USA
| | - Marjorie Solomon
- University of California, Davis, 4701 X St, Sacramento, CA 95817, USA
| | - J. Daniel Ragland
- University of California, Davis, 4701 X St, Sacramento, CA 95817, USA
| | - Cameron Carter
- University of California, Davis, 4701 X St, Sacramento, CA 95817, USA
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6
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Test-Retest Reliability of Functional Magnetic Resonance Imaging Activation for a Vergence Eye Movement Task. Neurosci Bull 2019; 36:506-518. [PMID: 31872328 DOI: 10.1007/s12264-019-00455-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 09/18/2019] [Indexed: 01/10/2023] Open
Abstract
Vergence eye movements are the inward and outward rotation of the eyes responsible for binocular coordination. While studies have mapped and investigated the neural substrates of vergence, it is not well understood whether vergence eye movements evoke the blood oxygen level-dependent signal reliably in separate experimental visits. The test-retest reliability of stimulus-induced vergence eye movement tasks during a functional magnetic resonance imaging (fMRI) experiment is important for future randomized clinical trials (RCTs). In this study, we established region of interest (ROI) masks for the vergence neural circuit. Twenty-seven binocularly normal young adults participated in two functional imaging sessions measured on different days on the same 3T Siemens scanner. The fMRI experiments used a block design of sustained visual fixation and rest blocks interleaved between task blocks that stimulated eight or four vergence eye movements. The test-retest reliability of task-activation was assessed using the intraclass correlation coefficient (ICC), and that of spatial extent was assessed using the Dice coefficient. Functional activation during the vergence eye movement task of eight movements compared to rest was repeatable within the primary visual cortex (ICC = 0.8), parietal eye fields (ICC = 0.6), supplementary eye field (ICC = 0.5), frontal eye fields (ICC = 0.5), and oculomotor vermis (ICC = 0.6). The results demonstrate significant test-retest reliability in the ROIs of the vergence neural substrates for functional activation magnitude and spatial extent using the stimulus protocol of a task block stimulating eight vergence eye movements compared to sustained fixation. These ROIs can be used in future longitudinal RCTs to study patient populations with vergence dysfunctions.
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7
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Császár N, Kapócs G, Bókkon I. A possible key role of vision in the development of schizophrenia. Rev Neurosci 2019; 30:359-379. [PMID: 30244235 DOI: 10.1515/revneuro-2018-0022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 08/01/2018] [Indexed: 12/12/2022]
Abstract
Based on a brief overview of the various aspects of schizophrenia reported by numerous studies, here we hypothesize that schizophrenia may originate (and in part be performed) from visual areas. In other words, it seems that a normal visual system or at least an evanescent visual perception may be an essential prerequisite for the development of schizophrenia as well as of various types of hallucinations. Our study focuses on auditory and visual hallucinations, as they are the most prominent features of schizophrenic hallucinations (and also the most studied types of hallucinations). Here, we evaluate the possible key role of the visual system in the development of schizophrenia.
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Affiliation(s)
- Noemi Császár
- Gaspar Karoly University Psychological Institute, H-1091 Budapest, Hungary.,Psychoszomatic Outpatient Department, H-1037 Budapest, Hungary
| | - Gabor Kapócs
- Buda Family Centred Mental Health Centre, Department of Psychiatry and Psychiatric Rehabilitation, St. John Hospital, Budapest, Hungary
| | - István Bókkon
- Psychoszomatic Outpatient Department, H-1037 Budapest, Hungary.,Vision Research Institute, Neuroscience and Consciousness Research Department, 25 Rita Street, Lowell, MA 01854, USA
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8
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Mayberry A, Tun Y, Hu P, Smith-Freedman D, Ganesan D, Marlin B, Salthouse C. CIDER: Enabling Robustness-Power Tradeoffs on a Computational Eyeglass. PROCEEDINGS OF THE ... ANNUAL INTERNATIONAL CONFERENCE ON MOBILE COMPUTING AND NETWORKING. INTERNATIONAL CONFERENCE ON MOBILE COMPUTING AND NETWORKING 2015; 2015:400-412. [PMID: 27042165 PMCID: PMC4813664 DOI: 10.1145/2789168.2790096] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The human eye offers a fascinating window into an individual's health, cognitive attention, and decision making, but we lack the ability to continually measure these parameters in the natural environment. The challenges lie in: a) handling the complexity of continuous high-rate sensing from a camera and processing the image stream to estimate eye parameters, and b) dealing with the wide variability in illumination conditions in the natural environment. This paper explores the power-robustness tradeoffs inherent in the design of a wearable eye tracker, and proposes a novel staged architecture that enables graceful adaptation across the spectrum of real-world illumination. We propose CIDER, a system that operates in a highly optimized low-power mode under indoor settings by using a fast Search-Refine controller to track the eye, but detects when the environment switches to more challenging outdoor sunlight and switches models to operate robustly under this condition. Our design is holistic and tackles a) power consumption in digitizing pixels, estimating pupillary parameters, and illuminating the eye via near-infrared, b) error in estimating pupil center and pupil dilation, and c) model training procedures that involve zero effort from a user. We demonstrate that CIDER can estimate pupil center with error less than two pixels (0.6°), and pupil diameter with error of one pixel (0.22mm). Our end-to-end results show that we can operate at power levels of roughly 7mW at a 4Hz eye tracking rate, or roughly 32mW at rates upwards of 250Hz.
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Affiliation(s)
| | - Yamin Tun
- University of Massachusetts, Amherst, Amherst, MA 01003
| | - Pan Hu
- University of Massachusetts, Amherst, Amherst, MA 01003
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Gracitelli CPB, Abe RY, Diniz-Filho A, Vaz-de-Lima FB, Paranhos A, Medeiros FA. Ophthalmology issues in schizophrenia. Curr Psychiatry Rep 2015; 17:28. [PMID: 25773224 PMCID: PMC4523638 DOI: 10.1007/s11920-015-0569-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Schizophrenia is a complex mental disorder associated with not only cognitive dysfunctions, such as memory and attention deficits, but also changes in basic sensory processing. Although most studies on schizophrenia have focused on disturbances in higher-order brain functions associated with the prefrontal cortex or frontal cortex, recent investigations have also reported abnormalities in low-level sensory processes, such as the visual system. At very early stages of the disease, schizophrenia patients frequently describe in detail symptoms of a disturbance in various aspects of visual perception that may lead to worse clinical symptoms and decrease in quality of life. Therefore, the aim of this review is to describe the various studies that have explored the visual issues in schizophrenia.
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Affiliation(s)
- Carolina P. B. Gracitelli
- Hamilton Glaucoma Center and Department of Ophthalmology, University of California, 9500 Gilman Drive, La Jolla, CA 92093-0946, USA; Department of Ophthalmology, Federal University of São Paulo, Botucatu Street, 821. Vila Clementino, São Paulo, SP 04023-062, Brazil
| | - Ricardo Y. Abe
- Hamilton Glaucoma Center and Department of Ophthalmology, University of California, 9500 Gilman Drive, La Jolla, CA 92093-0946, USA; ; Department of Ophthalmology, University of Campinas, Vital Brasil Street, 251, Cidade Universitária Zeferino Vaz, Campinas, SP 13083-970, Brazil
| | - Alberto Diniz-Filho
- Hamilton Glaucoma Center and Department of Ophthalmology, University of California, 9500 Gilman Drive, La Jolla, CA 92093-0946, USA; ; Department of Ophthalmology and Otorhinolaryngology, Federal University of Minas Gerais, Alfredo Balena Avenue, 190 Santa Efigenia, Belo Horizonte, MG 30130-100, Brazil
| | | | - Augusto Paranhos
- Department of Ophthalmology, Federal University of São Paulo, Botucatu Street, 821. Vila Clementino, São Paulo, SP 04023-062, Brazil;
| | - Felipe A. Medeiros
- Hamilton Glaucoma Center and Department of Ophthalmology, University of California, 9500 Gilman Drive, La Jolla, CA 92093-0946, USA;
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