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Schizophrenia is characterized by visual distortions in ~60% of cases, and visual hallucinations (VH) in ~25–50% of cases, depending on the sample. These symptoms have received relatively little attention in the literature, perhaps due to the higher rate of auditory vs. visual hallucinations in psychotic disorders, which is the reverse of what is f...
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Context 1
... hallucinations are not the only form of visual perceptual anomaly experienced in schizophrenia. For example, over 60% of people with schizophrenia experience visual distortions involving changes in clarity, form, brightness, color, motion, or persistence of visual stimuli (8,(12)(13)(14)(15)(16)(17)(18)) (see Table 1). It has also been reported that visual imagery is increased in people with schizophrenia (19). ...Citations
... 2,[7][8][9] Atypical visual performance in SCZ is often linked to a diminished influence of priors in Bayesian and predictive theories, [10][11][12][13] potentially resulting from deficits in top-down processing domains like attention and working memory. [14][15][16][17][18][19] However, empirical evidence is mixed, [20][21][22] with several studies also showing intact perceptual illusions in SCZ. 23,24 Serial dependence, wherein prior stimuli influence current perception, [25][26][27][28][29] has been recently used as a tool to investigate the influence of prior visual information in SCZ. ...
Background and Hypothesis
For a long time, it was proposed that schizophrenia (SCZ) patients rely more on sensory input and less on prior information, potentially leading to reduced serial dependence—ie, a reduced influence of prior stimuli in perceptual tasks. However, existing evidence is constrained to a few paradigms, and whether reduced serial dependence reflects a general characteristic of the disease remains unclear.
Study Design
We investigated serial dependence in 26 SCZ patients and 27 healthy controls (CNT) to evaluate the influence of prior stimuli in a classic visual orientation adjustment task, a paradigm not previously tested in this context.
Study Results
As expected, the CNT group exhibited clear serial dependence, with systematic biases toward the orientation of stimuli shown in the preceding trials. Serial dependence in SCZ patients was largely comparable to that in the CNT group.
Conclusions
These findings challenge the prevailing notion of reduced serial dependence in SCZ, suggesting that observed differences between healthy CNT and patients may depend on aspects of perceptual or cognitive processing that are currently not understood.
... In contrast to the vast research on auditory hallucinations in psychotic disorders, comparatively little attention has been devoted to visual hallucinations 1 . This may be because auditory hallucinations appear to be more common in psychotic disorders [2][3][4] , whereas visual hallucinations have traditionally been linked to organic and neurodegenerative conditions 2,5,6 . However, recent meta-analyses indicate that visual hallucinations are less rare in psychosis than previously assumed, with a weighted mean prevalence of 33% in first-episode psychosis (FEP) 7 and 27% in schizophrenia 6 . ...
... These associations between visual hallucinations and illness severity markers may be explained by shared genetic and neurodevelopmental vulnerabilities. Specifically, it has been suggested that the same genetic and neurodevelopmental factors that underlie a more severe psychopathology also increase the propensity for visual hallucinations and that visual hallucinations in psychosis may be related to larger detrimental neurodevelopmental changes 4,11,14 . This assumption is supported by findings of remarkably high prevalence rates of visual hallucinations in childhood-onset schizophrenia, a condition that is most often associated with poor long-term outcomes and with more pronounced genetic and neuroanatomical abnormalities 11,15 . ...
... This assumption is supported by findings of remarkably high prevalence rates of visual hallucinations in childhood-onset schizophrenia, a condition that is most often associated with poor long-term outcomes and with more pronounced genetic and neuroanatomical abnormalities 11,15 . Functional and structural brain imaging studies of schizophrenia patients substantiate these interpretations, with aberrations observed in those with visual hallucinations 14,16,17 and regions implicated in visual hallucinations affected in poor-outcome schizophrenia 4,18,19 . The association between visual hallucinations and a lower age at onset has also been interpreted to support a neurodevelopmental hypothesis of visual hallucinations 5,17 . ...
Visual hallucinations in psychosis are under-researched despite associations with increased illness severity, functional impairments, and suicidality in the few existing studies. Further, there are no long-term longitudinal studies, making it impossible to conclude if these associations are state or trait phenomena. In the current prospective longitudinal study, 184 individuals with first-episode psychosis were assessed with semi-structured clinical interviews and self-report questionnaires at baseline and 10-year follow-up. Participants were grouped based on lifetime experience of visual hallucinations: before or at baseline (VH+/+), first during follow-up (VH−/+), or never (VH−/−). Associations with functioning, suicide attempts, childhood trauma and other markers of illness severity were tested using multinomial logistic regression analysis. At baseline, the VH+/+ group (37.5%), but not VH−/+ (12.5%), had poorer functioning, higher symptom severity, a lower age at onset, and included more individuals with a history of multiple suicide attempts than the VH−/− group (50%). At follow-up, the VH−/+ group, but not VH+/+, had poorer functioning and higher symptom severity than the VH−/− group. However, the number of participants who committed multiple suicide attempts during the follow-up period was again significantly higher in the VH+/+ group. There was no association with childhood trauma. Hence, visual hallucinations are associated with impaired functioning and higher symptom severity, but only in the short-term. However, visual hallucinations that arise early in the course of illness are a risk indicator for repeated suicide attempts throughout the illness course. These findings highlight the relevance of assessing visual hallucinations and monitoring their development over time.
... In contrast to the vast research on auditory hallucinations in psychotic disorders, comparatively little attention has been devoted to visual hallucinations 1 . This may be because auditory hallucinations appear to be more common in psychotic disorders [2][3][4] , whereas visual hallucinations have traditionally been linked to organic and neurodegenerative conditions 2,5,6 . However, recent meta-analyses indicate that visual hallucinations are less rare in psychosis than previously assumed, with a weighted mean prevalence of 33% in first-episode psychosis (FEP) 7 and 27% in schizophrenia 6 . ...
... These associations between visual hallucinations and illness severity markers may be explained by shared genetic and neurodevelopmental vulnerabilities. Specifically, it has been suggested that the same genetic and neurodevelopmental factors that underlie a more severe psychopathology also increase the propensity for visual hallucinations and that visual hallucinations in psychosis may be related to larger detrimental neurodevelopmental changes 4,11,14 . This assumption is supported by findings of remarkably high prevalence rates of visual hallucinations in childhood-onset schizophrenia, a condition that is most often associated with poor long-term outcomes and with more pronounced genetic and neuroanatomical abnormalities 11,15 . ...
... This assumption is supported by findings of remarkably high prevalence rates of visual hallucinations in childhood-onset schizophrenia, a condition that is most often associated with poor long-term outcomes and with more pronounced genetic and neuroanatomical abnormalities 11,15 . Functional and structural brain imaging studies of schizophrenia patients substantiate these interpretations, with aberrations observed in those with visual hallucinations 14,16,17 and regions implicated in visual hallucinations affected in poor-outcome schizophrenia 4,18,19 . The association between visual hallucinations and a lower age at onset has also been interpreted to support a neurodevelopmental hypothesis of visual hallucinations 5,17 . ...
Background: Visual hallucinations are common across psychotic disorders and have been linked to impaired functioning and increased suicide risk. However, little is known about the stability of these associations over the long-term course of illness. Methods: 184 individuals with first-episode psychosis were assessed with semi-structured clinical interviews and self-report questionnaires at baseline and 10-year follow-up. Participants were grouped based on lifetime experience of visual hallucinations: before or at baseline (VH+/+), first during follow-up (VH-/+), or never (VH-/-). Associations with functioning, suicidal behavior, childhood trauma, and other markers of illness severity were tested using multinomial logistic regression analysis. Results: At baseline, the VH+/+ group (37.5%), but not VH-/+ (12.5%), had poorer functioning, higher symptom severity, a lower age at onset, and included more individuals with a history of severe suicidal behavior (multiple suicide attempts) than the VH-/- group (50%). At follow-up, the VH-/+ group, but not VH+/+, had poorer functioning and higher symptom severity than the VH-/- group. However, rates of severe suicidal behavior displayed during the follow-up period were again significantly higher in the VH+/+ group. There was no association with childhood trauma. Conclusions: Visual hallucinations are associated with impaired functioning and higher symptom severity, but only in the short-term. Visual hallucinations which arise early in the course of illness are a risk indicator for severe suicidal behavior throughout the illness course. These findings highlight the relevance of assessing visual hallucinations and monitoring their development over time.
... Schizophrenia is characterized by visual distortions in upto 60% of the individuals, including changes in clarity form, brightness, color, motion or persistence of visual stimuli (Silverstein & Lai 2021). Difficulties in facial recognition, misreading others' facial expressions, and misidentifying individuals have also been described (Torrey & Yolken 2017). ...
Consultation Liaison Psychiatry (CLP) deals with the interface shared between psychiatry and various other disciplines of medicine. The interface shared by psychiatry and ophthalmology is among the lesser discussed ones in the field of CLP, despite the fact that it holds clinical relevance in the evaluation, management and outcomes of both psychiatric and ophthalmological disorders. This narrative review focusses on the ophthalmological aspects of psychiatric disorders, with respect to their manifestations, assessment, and management. Psychiatric disorders, including schizophrenia, affective disorders, 'functional' disorders, and substance use disorders, have numerous ophthalmic manifestations, which can have clinical implications for the patients. Even the psychotropic drugs given for psychiatric disorders can lead to side effects affecting the eye, but these are among the lesser-discussed side effects. Some psychiatric disorders can be investigated using various ophthalmic functions, the assessments ranging from simple physical examination to the use of instruments like a fundoscope, which can be useful for a psychiatrist in their routine practice. Lastly, eye functions can also be used in the treatment of psychiatric conditions, as is seen in eye movement desensitization and reprocessing. This review reiterates the fact that more attention needs to be given to the field of 'psycho-ophthalmology', which holds great promise in the coming days.
... Given that the external world provides essentially the same visual information to all humans, differences in how stimuli are perceived are due to internal sensory processes that vary across people. In psychotic psychopathology these internal sensory processes produce hallucinations and illusions (Silverstein and Lai, 2021). Although a variety of visual perceptual abnormalities have been documented in psychotic psychopathology (Silverstein and Keane, 2011), it remains unclear what endogenous sensory processes give rise to disturbed perception. ...
Introduction
Psychosis is in part defined by disturbances in perception. Recent investigations have implicated the speed of alpha oscillations observed in brain electrical activity as reflective of a sampling rate of the visual environment and perception. Although both slowed alpha oscillations and aberrant percept formation are evident in disorders of psychotic psychopathology such as schizophrenia it is unclear whether slow alpha accounts for abnormal visual perception in these disorders.
Methods
To examine the role of the speed of alpha oscillations in perception in psychotic psychopathology we gathered resting-state magneto-encephalography data from probands with psychotic psychopathology (i.e., schizophrenia, schizoaffective disorder, and bipolar disorder with a history of psychosis), their biological siblings, and healthy controls. We appraised visual perceptual function without the confound of cognitive ability and effort through the use of a simple binocular rivalry task.
Results
We found a slowed pace of alpha oscillations in psychotic psychopathology that was associated with longer percept durations during binocular rivalry, consistent with the assertion that occipital alpha oscillations govern the rate of accumulation of visual information used to generate percepts. Alpha speed varied widely across individuals with psychotic psychopathology and was highly stable across several months indicating that it is likely a trait characteristic of neural function that is relevant to visual perception. Finally, a lower speed of alpha oscillation was associated with a lower IQ and greater disorder symptomatology implying that the effects of the endogenous neural oscillation on visual perception may have wider consequences for everyday functioning.
Discussion
Slowed alpha oscillations in individuals with psychotic psychopathology appear to reflect altered neural functions related to percept formation.
... Approximately 60% of individuals with schizophrenia have distortions in visual perception (Phillipson & Harris, 1985), and >33% experience visual hallucinations (Silverstein & Lai, 2021). The range of perceptual deficits is broad and includes worse performance in assessments of contrast sensitivity (Harper et al., 2020), detection of contour (Keane et al., 2014), colour (Fernandes et al., 2019), biological motion (Okruszek & Pilecka, 2017, but see Keane, Peng, et al., 2018), faces (McCleery et al., 2015) and stronger afterimages F I G U R E 3 Illustration of differences in mismatch negativity where individuals with schizophrenia show the smallest mismatch negativity (MMN) (grey), followed by high schizotypy/subclinical individuals (grey, dark line) and low schizotypy showing the largest MMN (black). ...
... Similarly, accounts for visual deficits in schizophrenia spectrum disorders identify abnormalities in the anatomy of the retina (reviewed in Bernardin et al., 2017;Silverstein et al., 2020), as well as atypical network-level connectivity, both hypo-and hyper-connectivity, including cortical-medial temporal lobe abnormalities (reviewed in Silverstein & Lai, 2021). Together, the consistent oculomotor and low-level visual deficits suggest that processing from as early as the retina is abnormal in schizophrenia. ...
The search for robust, reliable biomarkers of schizophrenia remains a high priority in psychiatry. Biomarkers are valuable because they can reveal the underlying mechanisms of symptoms and monitor treatment progress, and may predict future risk of developing schizophrenia. Despite the existence of various promising biomarkers that relate to symptoms across the schizophrenia‐spectrum, and despite published recommendations encouraging multivariate metrics, they are rarely investigated simultaneously within the same individuals. In those with schizophrenia, the magnitude of purported biomarkers is complicated by comorbid diagnoses, medications, and other treatments. Here, we argue three points. First, we reiterate the importance of assessing multiple biomarkers simultaneously. Second, we argue that investigating biomarkers in those with schizophrenia‐related traits (schizotypy) in the general population can accelerate progress in understanding the mechanisms of schizophrenia. We focus on biomarkers of sensory and working memory in schizophrenia and their smaller effects in individuals with nonclinical schizotypy. Third, we note irregularities across research domains leading to the current situation in which there is a preponderance of data on auditory sensory memory and visual working memory, but markedly less in visual (iconic) memory and auditory working memory, particularly when focusing on schizotypy where data are either scarce or inconsistent. Together, this review highlights opportunities for researchers without access to clinical populations to address gaps in knowledge. We conclude by highlighting the theory that early sensory memory deficits contribute negatively to working memory and vice versa. This presents a mechanistic perspective where biomarkers may interact with one another and impact schizophrenia‐related symptoms.
... Approximately 60% of individuals with schizophrenia have distortions in visual perception (Phillipson & Harris, 1985), and >33% experience visual hallucinations (Silverstein & Lai, 2021). The range of perceptual deficits is broad and includes worse performance in assessments of contrast sensitivity (Harper et al., 2020), detection of contour (Keane et al., 2014), colour (Fernandes et al., 2019), biological motion (Okruszek & Pilecka, 2017, but see Keane, Peng, et al., 2018), faces (McCleery et al., 2015) and stronger afterimages F I G U R E 3 Illustration of differences in mismatch negativity where individuals with schizophrenia show the smallest mismatch negativity (MMN) (grey), followed by high schizotypy/subclinical individuals (grey, dark line) and low schizotypy showing the largest MMN (black). ...
... Similarly, accounts for visual deficits in schizophrenia spectrum disorders identify abnormalities in the anatomy of the retina (reviewed in Bernardin et al., 2017;Silverstein et al., 2020), as well as atypical network-level connectivity, both hypo-and hyper-connectivity, including cortical-medial temporal lobe abnormalities (reviewed in Silverstein & Lai, 2021). Together, the consistent oculomotor and low-level visual deficits suggest that processing from as early as the retina is abnormal in schizophrenia. ...
The search for robust, reliable biomarkers of schizophrenia remains a high priority in psychiatry. Biomarkers are valuable because they can track symptom progression and monitor treatment progress, and may predict who is at-risk of developing schizophrenia in the future. Despite the existence of various promising biomarkers that relate to symptoms across the schizophrenia-spectrum, and despite published recommendations encouraging multivariate metrics, they are rarely investigated simultaneously within the same individuals. In those with schizophrenia, the magnitude of purported biomarkers is complicated by comorbid diagnoses, medications, and other treatments. Here, we argue two points. First, we reiterate the importance of assessing multiple biomarkers simultaneously. Second, we argue that investigating biomarkers in those with schizophrenia-related traits (schizotypy) in the general population can accelerate progress in understanding the mechanisms of schizophrenia. We focus on biomarkers of sensory and working memory in schizophrenia and their smaller effects in individuals with nonclinical high schizotypy. We note irregularities across research domains leading to the current situation in which there is a preponderance of data on auditory sensory memory and visual working memory, but markedly less in visual (iconic) memory and auditory working memory. This imbalance is particularly evident when focusing on schizotypy. Together, this review highlights opportunities to address gaps in knowledge. We conclude by highlighting the theory that early sensory memory deficits contribute negatively to working memory and vice versa. This presents a mechanistic perspective where biomarkers may interact with one another and impact schizophrenia-related symptoms.
... In schizophrenia, previous research highlights abnormalities of visual information processing along both visual streams including retinal dysfunctions with a predominance of alterations observed related to the dorsal visual stream [3,[9][10][11][12][13][60][61][62]. For instance, basic visual symptoms correlated with rapid visual processing and magnocellular pathway function [63]. ...
Subtle subjective visual dysfunctions (VisDys) are reported by about 50% of patients with schizophrenia and are suggested to predict psychosis states. Deeper insight into VisDys, particularly in early psychosis states, could foster the understanding of basic disease mechanisms mediating susceptibility to psychosis, and thereby inform preventive interventions. We systematically investigated the relationship between VisDys and core clinical measures across three early phase psychiatric conditions. Second, we used a novel multivariate pattern analysis approach to predict VisDys by resting-state functional connectivity within relevant brain systems. VisDys assessed with the Schizophrenia Proneness Instrument (SPI-A), clinical measures, and resting-state fMRI data were examined in recent-onset psychosis (ROP, n = 147), clinical high-risk states of psychosis (CHR, n = 143), recent-onset depression (ROD, n = 151), and healthy controls (HC, n = 280). Our multivariate pattern analysis approach used pairwise functional connectivity within occipital (ON) and frontoparietal (FPN) networks implicated in visual information processing to predict VisDys. VisDys were reported more often in ROP (50.34%), and CHR (55.94%) than in ROD (16.56%), and HC (4.28%). Higher severity of VisDys was associated with less functional remission in both CHR and ROP, and, in CHR specifically, lower quality of life (Qol), higher depressiveness, and more severe impairment of visuospatial constructability. ON functional connectivity predicted presence of VisDys in ROP (balanced accuracy 60.17%, p = 0.0001) and CHR (67.38%, p = 0.029), while in the combined ROP + CHR sample VisDys were predicted by FPN (61.11%, p = 0.006). These large-sample study findings suggest that VisDys are clinically highly relevant not only in ROP but especially in CHR, being closely related to aspects of functional outcome, depressiveness, and Qol. Findings from multivariate pattern analysis support a model of functional integrity within ON and FPN driving the VisDys phenomenon and being implicated in core disease mechanisms of early psychosis states.
... We found that the dFNC of the rECN-mVN is lower in patients with schizophrenia than healthy controls, indicating that schizophrenia may affect the selective handling of relevant information. In addition, a previous study revealed that the visual cortex is related to visual hallucinations (Silverstein & Lai, 2021;Carter & Ffytche, 2015), and ECN is related to auditory hallucinations (Hugdahl, 2009). However, our findings are limited to a resting-state analysis. ...
Schizophrenia is a chronic mental disorder characterized by continuous or relapsing episodes of psychosis. While previous studies have detected functional network connectivity alterations in patients with schizophrenia, and most have focused on static functional connectivity. However, brain activity is believed to change dynamically over time. Therefore, we computed dynamic functional network connectivity using the sliding window method in 38 patients with schizophrenia and 31 healthy controls. We found that patients with schizophrenia exhibited higher occurrences in the weakly and sparsely connected state (state 3) than healthy controls, positively correlated with negative symptoms. In addition, patients exhibited fewer occurrences in a strongly connected state (state 4) than healthy controls. Lastly, the dynamic functional network connectivity between the right executive-control network and the medial visual network was decreased in schizophrenia patients compared to healthy controls. Our results further prove that brain activity is dynamic, and that alterations of dynamic functional network connectivity features might be a fundamental neural mechanism in schizophrenia.
... For example, there are impairments in low-level visual processing in schizophrenia (eg, in contrast, sensitivity and visual acuity) that may be retinal in origin. [126][127][128][129] Also, some of the visual distortions and hallucinations reported by patients (in approximately 65% and over 25% of cases, respectively) [130][131][132] are similar to what is observed in other conditions with retinal impairments. 53,126,[133][134][135][136][137] Possible effects of retinal disturbances on other aspects of vision in schizophrenia have been reviewed elsewhere. ...
Schizophrenia is increasingly recognized as a systemic disease, characterized by dysregulation in multiple physiological systems (eg, neural, cardiovascular, endocrine). Many of these changes are observed as early as the first psychotic episode, and in people at high risk for the disorder. Expanding the search for biomarkers of schizophrenia beyond genes, blood, and brain may allow for inexpensive, noninvasive, and objective markers of diagnosis, phenotype, treatment response, and prognosis. Several anatomic and physiologic aspects of the eye have shown promise as biomarkers of brain health in a range of neurological disorders, and of heart, kidney, endocrine, and other impairments in other medical conditions. In schizophrenia, thinning and volume loss in retinal neural layers have been observed, and are associated with illness progression, brain volume loss, and cognitive impairment. Retinal microvascular changes have also been observed. Abnormal pupil responses and corneal nerve disintegration are related to aspects of brain function and structure in schizophrenia. In addition, studying the eye can inform about emerging cardiovascular, neuroinflammatory, and metabolic diseases in people with early psychosis, and about the causes of several of the visual changes observed in the disorder. Application of the methods of oculomics, or eye-based biomarkers of non-ophthalmological pathology, to the treatment and study of schizophrenia has the potential to provide tools for patient monitoring and data-driven prediction, as well as for clarifying pathophysiology and course of illness. Given their demonstrated utility in neuropsychiatry, we recommend greater adoption of these tools for schizophrenia research and patient care.
