What visual illusions teach us about schizophrenia

Probably not a substantial claim: may not pass S1 (asserted). May combine two claims.

Some authors have argued that the impairment of gain control is a robust and significant property of visual processing in schizophrenia, and may even consider it a core feature of the disorder.

“Some authors have argued, in line with the findings that stem from the study of VIs, that the impairment of gain control is a robust and significant property of visual processing in schizophrenia, and may even consider it a core feature of the disorder (Robol et al., 2013; Tibber et al., 2013).”

• cites Robol et al., 2013 sourceNot checked yet

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• cites Tibber et al., 2013 sourceNot checked yet

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Classified as probably not a substantial claim. May combine two claims.

Yang et al. and Tibber et al. hypothesized that pre-cortical stages of the visual system, in which luminance is supposed to be processed, were spared, thereby contradicting Norton's conclusions.

“Thus, these authors hypothesized that the pre-cortical stages of the visual system, in which luminance is supposed to be processed, were spared, thereby contradicting Norton's conclusions.”

• cites Yang et al., 2012 sourceNot checked yet

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• cites Tibber et al., 2013 sourceNot checked yet

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May combine two claims.

Yang et al. (2012) and Tibber et al. (2013) found that luminance context processing was similar in patients and controls, whereas the strength of illusions was inferior in patients for other psychophysical parameters (e.g., contrast, orientation, size or motion).

“Yang et al. (2012) and Tibber et al. (2013) found that luminance context processing was similar, whereas the strength of the illusions was inferior in patients for the other psychophysical parameters (e.g., contrast, orientation, size or motion).”

• cites Yang et al., 2012 sourceNot checked yet

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• cites Tibber et al., 2013 sourceNot checked yet

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May combine two claims.

VIs pinpoint the limits of purely anatomoclinical or linear causal models and underline the complexity and specificity of visual perception in schizophrenia.

“VIs, although polymorphic, pinpoint the limits of purely anatomoclinical or linear causal models and underline, in contrast, the complexity and specificity of visual perception in schizophrenia.”

Probably not a substantial claim: may not pass S4 (based).

Many VIs refer to a basic perceptual phenomenon called the context or surround suppression effect, which can be conceptualized as a form of gain control.

“Although not always labeled as such, many VIs refer to a basic perceptual phenomenon called the context or surround suppression effect, which can be conceptualized as a form of gain control.”

May combine two claims.

Perceptual organization can be viewed as relying on two main fundamental mechanisms: gain control and integration, both of which could be impaired in schizophrenia.

“According to Butler et al. (2008) this phenomenon of perceptual organization can be viewed as relying on two main fundamental mechanisms: gain control and integration, both of which could be impaired in schizophrenia.”

• cites Butler et al., 2008 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

Norton et al. argued that the temporal alteration in the Three-flash illusion may rely on a faulty sensory-integration within the very first stages of the visual stream.

“They argued that this temporal alteration may rely on a faulty sensory-integration within the very first stages of the visual stream.”

• cites Norton et al., 2008 sourceNot checked yet

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May combine two claims.

Increased performance in patients on VI tasks cannot be attributed to general task difficulty, a lack of attention or motivation, or a disease-related global deficit.

“From a methodological point of view, increased performance in patients cannot be attributed to general task difficulty, a lack of attention or motivation or to a disease-related global deficit.”

Probably not a substantial claim: may not pass S4 (based).

The surround-suppression paradigm appears exposed to specific methodological issues and covariates that may be imputed in the results.

“This paradigm appears exposed to specific methodological issues and covariates that may be imputed in the results”

May combine two claims.

Over-trusted sensory signals become over-salient and unpredictable; they could be transmitted up the hierarchy, but no adjustments could fully resolve the aberrancy.

“Artificially over-trusted, sensory signals become over-salient and unpredictable. They could be transmitted up the hierarchy, but no adjustments could fully resolve the aberrancy (Fletcher and Frith, 2008).”

• cites Fletcher and Frith, 2008 sourceNot checked yet

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• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

Classified as probably not a substantial claim.

Chen et al. (2008) proposed that context interaction impairment in schizophrenia may be better accounted for by alterations of surround inhibition rather than surround facilitation.

“The authors proposed that context interaction impairment in schizophrenia may be better accounted for by alterations of surround inhibition rather than surround facilitation.”

• cites Chen et al., 2008 sourceNot checked yet

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May combine two claims.

If both descending and climbing loops are impaired, both sensory evidence and prior knowledge are reverberated and over-counted, resulting in an overconfident but not biased inferred belief in the Predictive Coding framework.

“If both descending and climbing loops are impaired (A), both sensory evidence and prior knowledge are reverberated and over counted (multiplication of the pink and violet arrows). In the Predictive coding framework, this results in an overconfident (narrowing of the posterior distribution) but not biased (unchanged K) inferred belief.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.
• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

May combine two claims.

Visual perception plays an important role in the psychopathology of schizophrenia and constitutes a unique way to explore the underlying mechanisms of reality construction.

“several authors have defended the idea that visual perception plays an important role in the psychopathology of schizophrenia (Butler and Javitt, 2005), and constitutes a unique way to explore the underlying mechanisms of reality construction (Silverstein and Keane, 2011).”

• cites Butler and Javitt, 2005Not checked yet

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• cites Silverstein and Keane, 2011Not checked yet

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• AssumptionThe authors state this as an assumption: Perception is closely interwoven with other high-level functions such as belief genesis or reasoning.

Classified as probably not a substantial claim.

In Bayesian accounts, positive symptoms of schizophrenia are imputed to an imbalance in the relative weight or precision attributed to the prior and sensory evidence, causing false inferences.

“By relying on the Bayesian formalism, authors typically impute the positive symptoms of schizophrenia to an imbalance in the relative weight or precision attributed to the prior and sensory evidence, which, in turn, causes false inferences.”

• AssumptionThe authors state this as an assumption: Sensory inputs are inherently ambiguous.

Classified as probably not a substantial claim.

The Müller-Lyer illusion can be explained by internalized rules of perspective leading an individual to compute the line flanked with converging fins as if it were further away, so its shorter appearance conflicts with the actual identical size of the two lines.

“According to this author, the internalized rules of perspective (i.e., prior knowledge) lead an individual to compute the line flanked with converging fins as if it were further away. Consequently, the line's shorter appearance conflicts with the actual identical size of the two lines.”

• cites GregoryNot checked yet

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Probably not a substantial claim: may not pass S4 (based).

VIs are an illustration of the perceptual system's ability to bind and group visual elements into coherent patterns, which leads to a meaningful representation.

“VIs are an illustration of the perceptual system's ability to bind and group visual elements into coherent patterns, which leads to a meaningful representation.”

May combine two claims.

Predictive Coding and Circular Inference frameworks are algorithmically similar and may essentially differ in the type of variables considered.

“Importantly, despite conceptual differences, these frameworks are algorithmically similar and may essentially differ in the type of variables considered (e.g., binary vs. continuous, see Jardri and Deneve, 2013).”

• cites Jardri and Deneve, 2013Not checked yet

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Probably not a substantial claim: may not pass S4 (based).

The physiological existence of VIs suggests that deceiving perception paradoxically requires the integrity of the different subcomponents of the visual system.

“The physiological existence of VIs suggests that deceiving perception paradoxically requires the integrity of the different subcomponents of the visual system.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Gain control of neural responses is achieved through a combination of intrinsic neuronal properties, lateral interactions and feedback modulations.

“Gain control of neural responses is achieved through a combination of intrinsic neuronal properties, lateral interactions and feedback modulations (Must et al., 2004).”

• cites Must et al., 2004 sourceNot checked yet

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May combine two claims.

Some evidence suggests that surround suppression and its impairment depends on several variables, such as the contrast and the time of presentation, which counters an absolute independent process.

“Some evidence suggests that surround suppression and its impairment depends on several variables, such as the contrast (previously discussed) and the time of presentation (Calvert and Harris, 1988; Bressan and Kramer, 2013), which counters an absolute independent process.”

• cites Calvert and Harris, 1988Not checked yet

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• cites Bressan and Kramer, 2013Not checked yet

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May combine two claims.

The bias toward prior knowledge in the Hollow mask illusion is better understood as an optimal inference combining bottom-up and top-down information, supporting adaptation in a noisy environment.

“However, rather than a perceptual error, this bias is better understood as the consequence of inferences that optimally combine bottom-up and top-down information (see Boxes 1, 3), which supports the best adaptation in a noisy environment.”

May combine two claims.

This disturbance from large-scale dysconnectivity would result in aberrant concept formation, delusions, and hallucinations.

“This disturbance would result in aberrant concept formation, delusions, and hallucinations.”

Probably not a substantial claim: may not pass S3 (load-bearing).

A lack of statistical power is a major cause of concern in neuroscience and may be imputed for several studies.

“even if a lack of statistical power is a major cause of concern in neuroscience and may be imputed for several studies (Button et al., 2013)”

• cites Button et al., 2013 sourceNot checked yet

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May combine two claims.

In healthy controls, a model with connectivity modulation from higher-level areas to V1 better accounted for data, whereas in schizophrenia patients DCM revealed a reverse pattern with predominance of feedforward modulation.

“While a model that places connectivity modulation from the higher-level areas to the primary visual cortex (i.e., V1) better accounted for healthy control data, the DCM revealed a reverse pattern in schizophrenia patients (i.e., the predominance of the feedforward modulation).”

• cites Dima et al., 2009 sourceNot checked yet

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• cites Dima et al., 2010 sourceNot checked yet

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Probably not a substantial claim: may not pass S1 (asserted).

Some authors have argued that excessively precise prior expectations, corresponding to a smaller-than-normal gain for prediction errors, better account for hallucinatory experiences.

“However, in opposition to a theory of over salient sensory evidence, some authors have argued that excessively precise prior expectations, which correspond to a smaller-than-normal gain for prediction errors, better account for hallucinatory experiences.”

• cites Friston, 2005bNot checked yet

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• cites Chambon et al., 2011 sourceNot checked yet

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• cites Schmack et al., 2013 sourceNot checked yet

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• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

Probably not a substantial claim: may not pass S4 (based).

Depending on which loops are mostly impaired, the Circular Inference model predicts that either sensory information or priors will dominate the final percept.

“Depending on which loops are mostly impaired, the model predicts that either sensory information or priors will dominate the final percept.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

The conflict between contradictory hypotheses about prediction error gain (larger or smaller than normal, over-trusted prior or over-counted sensory evidence) has never been fully resolved, making experimental testing difficult.

“Note that the conflict between apparently contradictory hypotheses (gains of prediction errors larger than normal or smaller than normal, over-trusted prior or over-counted sensory evidence) has never been fully resolved, which renders the experimental testing of these theories extremely difficult.”

May combine two claims.

Even when facing weak or non-existent sensory evidence, circular propagation generates strong perceptual beliefs, so hallucinations occur where nothing relevant should have been inferred.

“Even when facing weak or non-existent sensory evidence, the circular propagation generates strong perceptual beliefs: hallucinations occur where nothing relevant should have been inferred.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

May combine two claims.

Circular inference introduces spurious correlations between sensory and prior messages that are non-existent in the real world, leading to learning and consolidation of unshakable but false causal relationships and delusional belief systems.

“In the same way, circular inference introduces spurious correlations between sensory (feedforward) and prior (feedback) messages that are non-existent in the real world. This leads to the learning and consolidation of “unshakable” (but false) causal relationships, resulting in delusional belief systems.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

May combine two claims.

A deficit in control of downward loops would predict over-confidence in prior knowledge and higher susceptibility to perceptual illusions.

“Vice-versa, a deficit in the control of downward loops (e.g., prior expectations that activate lower levels and are misinterpreted as sensory information when they are reverberated back up the hierarchy) would predict an over-confidence in the prior knowledge and a higher susceptibility to perceptual illusions.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

May combine two claims.

In the Circular Inference model, excitatory/inhibitory imbalance renders the system unable to avoid circular propagation of beliefs: bottom-up sensory evidence is reverberated back down as prior information and combined with itself, and prior expectations can generate fake sensory representations that reinforce prior expectations.

“In their model, Jardri and Denève showed how excitatory/inhibitory imbalance renders the system unable to avoid circular propagation of beliefs: bottom-up sensory evidence are reverberated back down as if they were prior information (upward loops), and thus combined with themselves until weak sensory inputs or meaningless coincidences are attributed to highly trusted high-level interpretations.”

• cites Jardri and Deneve, 2013Not checked yet

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• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

Probably not a substantial claim: may not pass S3 (load-bearing).

Several authors have related auditory hallucinations to an over-saliency of inner speech, considered a covert motor action, which is misattributed to an alien source.

“Several authors have also related auditory hallucinations to an over-saliency of the inner speech (considered a covert motor action), which is misattributed to an alien source (McGuire et al., 1995; Allen et al., 2007; Moseley et al., 2013).”

• cites McGuire et al., 1995 sourceNot checked yet

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• cites Allen et al., 2007 sourceNot checked yet

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• cites Moseley et al., 2013 sourceNot checked yet

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• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

May combine two claims.

Asymmetrically impairing the inhibitory loops biases the inferential system in two opposite ways that both may generate the same aspecific perceptual phenomenon.

“Thus, asymmetrically impairing the inhibitory loops biases the inferential system in two opposite ways that both may generate the same aspecific perceptual phenomenon.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

May combine two claims.

A deficit in control of upward loops would cause over-confidence in sensory evidence and lower susceptibility to perceptual illusions.

“Indeed, a deficit in the control of upward loops (e.g., sensory evidence that reaches a high level representation and is then misinterpreted as prior knowledge when it is reverberated back down) would cause an over-confidence in sensory evidence and a lower susceptibility to perceptual illusions.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

May combine two claims.

Systemic administration of a GABAA agonist (lorazepam) lengthens percept durations and decreases switch rates.

“More importantly, the authors then experimentally confirmed these predictions by observing, after the systemic administration of a GABAA agonist (lorazepam), a lengthening of the percept durations and a decrease in the switch rates (Van Loon et al., 2013).”

• cites Van Loon et al., 2013 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

The neurophysiological processes that cause the inferential imbalance remain unclear.

“Finally, the neurophysiological processes that cause this imbalance remain unclear.”

Probably not a substantial claim: may not pass S4 (based).

The effects of circular inference are aggravated by an asymmetric impairment predominantly affecting either the upward or downward loops.

“This would be aggravated by an asymmetric impairment predominantly affecting either the upward or downward loops.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

May combine two claims.

If the impairment only affects climbing loops, sensory evidence but not prior knowledge is reverberated; the prediction error is emphasized and the inferred belief is biased toward sensory evidence.

“In contrast, when the impairment only affects climbing loops (B), sensory evidence, but not prior knowledge, is reverberated. The prediction error is emphasized (K is too large), and the inferred belief is biased toward sensory evidence.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.
• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

May combine two claims.

In cortical networks, excitatory-inhibitory balance is tightly maintained and appears affected in schizophrenia.

“Indeed such balance is tightly maintained in cortical networks, and appears to be affected in schizophrenia (O'Donnell, 2011).”

• cites O'Donnell, 2011 sourceNot checked yet

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May combine two claims.

When facing a visual illusion, controls show top-down counter-balancing, whereas schizophrenia patients exhibit strengthening of bottom-up processes that prevent them from perceiving the illusory effect.

“When facing a VI (i.e., a complex perceptual task), a tendency toward a top-down counter-balancing is observed in controls, whereas patients who suffer from schizophrenia exhibit a strengthening of the bottom-up processes that prevent them from perceiving the illusory effect.”

May combine two claims.

Patients with schizophrenia failed to correct for the inverted Hollow Mask to a more plausible interpretation, which can be explained by an underweighting of prior knowledge during perceptual inferences.

“The fact that patients with schizophrenia failed to correct for the inverted Hollow Mask to a more plausible (or predictable) interpretation can also be explained by an underweighting of prior knowledge during perceptual inferences (Schmeider et al., 1996; Schneider et al., 2002; Koethe et al., 2009).”

• cites Schmeider et al., 1996 sourceNot checked yet

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• cites Schneider et al., 2002 sourceNot checked yet

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• cites Koethe et al., 2009 sourceNot checked yet

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Probably not a substantial claim: may not pass S1 (asserted). May combine two claims.

According to the excessively precise prior hypothesis, perception distances itself from sensory stimuli and becomes dependent on prior knowledge, so one would only perceive what one is expecting to perceive.

“According to this hypothesis, perception distances itself from the sensory stimuli and becomes dependent on prior knowledge of the world (Friston, 2005b; Chambon et al., 2011; Schmack et al., 2013); thus, one would only perceive what one is expecting to perceive.”

• cites Friston, 2005bNot checked yet

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• cites Chambon et al., 2011 sourceNot checked yet

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• cites Schmack et al., 2013 sourceNot checked yet

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• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

May combine two claims.

If the inhibitory disequilibrium disfavors descending loops, only prior knowledge is over-counted; the prediction error is minimized and the posterior is biased toward expectations.

“If, in contrast, the inhibitory disequilibrium disfavors the descending loops (C), only the prior knowledge is over counted because of its reverberation. The prediction error is then minimized (K is too small), and the resulting posterior is biased toward expectations.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.
• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

Classified as probably not a substantial claim. May combine two claims.

A disrupted inferential system may fail to attenuate the sensory consequences of self-generated acts; the resulting overweighed prediction error drives otherwise silent percepts into awareness, which is then misattributed to an external agent.

“Conversely, a disrupted inferential system may fail to attenuate the sensory consequences of self-generated acts. Artificially overweighed, the resulting prediction error would then drive otherwise silent percepts to emerge into awareness. The only way to account for this unusual experience is then to misattribute it to an external agent.”

• AssumptionThe authors state this as an assumption: In Predictive Coding, the prior and the likelihood have a Gaussian distribution.

May combine two claims.

Psychotic manifestations can be understood as resulting from circular inferences, which cause overconfidence, surinterpretations of weak sensory data, and dissociations between high-level and low-level representations.

“Psychotic manifestations can be understood as resulting from such circular inferences, which cause overconfidence, surinterpretations of weak sensory data and dissociations between high-level and low-level representations.”

• AssumptionThe authors state this as an assumption: In the brain's hierarchy, top-down and bottom-up beliefs should be propagated only once in each direction, and this requires equally strong inhibitory loops to cancel excitatory feedforward/feedback loops.
• AssumptionRests on an assumption: Long-range connections in the brain are overwhelmingly excitatory.

Probably not a substantial claim: may not pass S4 (based).

Frequent methodological issues, such as inter-group comparability, have made findings on the links between visual illusion sensitivity and clinical features difficult to interpret.

“Despite an abundant literature dealing with this matter, frequent methodological issues (e.g., inter-group comparability) have made the findings difficult to interpret.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Adult patients with schizophrenia are more concerned by auditory compared with visual hallucinations.

“Importantly, while VIs provide a privileged access to the visual hallucinatory modality, readers should note that adult patients who suffer from schizophrenia are more concerned by auditory compared with visual hallucinations (Mueser et al., 1990; Blom, 2010).”

• cites Mueser et al., 1990 sourceNot checked yet

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• cites Blom, 2010 sourceNot checked yet

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Probably not a substantial claim: may not pass S4 (based).

An asymmetric impairment in the excitatory-inhibitory balance, consisting of overweighting prior information relative to sensory evidence caused by insufficient inhibitory control of downward loops, could explain the concomitant increase in hallucinations and illusions in Parkinson's disease.

“asymmetric impairment in the excitatory-inhibitory balance (i.e., an overweighting of prior information relative to the sensory evidence, which is caused by an insufficient inhibitory control of downward loops). This impairment could explain the concomitant increase in hallucinations and illusions in Parkinson's disease (as could the Predictive Coding model).”

May combine two claims.

The opposite profile of asymmetric circular belief propagation, selective impairment of upward loops, predicts opposite increased vulnerability to visual illusions but similar symptoms.

“Interestingly, the opposite profile of asymmetric circular belief propagation (selective impairment of upward loops) predicts opposite (increased) vulnerability to VIs but similar symptoms.”

May combine two claims.

Resistance to visual illusions is not a specific perceptual property of schizophrenia and is not an endophenotypic marker for psychosis in general.

“Thus, these converging clues prompt one to refute the idea that resistance to VIs is a specific perceptual property of schizophrenia and, hence, an endophenotypic marker for psychosis in general.”

Classified as probably not a substantial claim. May combine two claims.

Under the Circular Inference model, aberrant experiences in schizophrenia may be understood as immersion in a world dominated by sensory evidence, while top-down influences lose their organizing and structuring potential.

“Considering the Circular Inference model, aberrant experiences in schizophrenia may be understood as an immersion in a world dominated by sensory evidence, while top-down influences lose their organizing and structuring potential.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Some authors found no or only weak relationships between visual illusions and psychopathology.

“While some authors found no or only weak relationships between VIs and psychopathology (Koethe et al., 2006, 2009; Tibber et al., 2013; Yang et al., 2013)”

• cites Koethe et al., 2006, 2009Not matched

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• cites Tibber et al., 2013 sourceNot checked yet

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• cites Yang et al., 2013 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

In Parkinson's disease, one quarter of patients suffer from visual hallucinations and visual misperceptions.

“This tendency is noteworthy in the case of Parkinson's disease, in which one quarter of patients suffer from visual hallucinations and visual misperceptions (Diederich et al., 2009).”

• cites Diederich et al., 2009 sourceNot checked yet

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Probably not a substantial claim: may not pass S3 (load-bearing).

Visual hallucinations in schizophrenia have a substantial point prevalence of 27%.

“The authors reported visual hallucinations with a substantial point prevalence of 27% (Waters et al., 2014).”

• cites Waters et al., 2014 sourceNot checked yet

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Classified as probably not a substantial claim. May combine two claims.

According to the hypothesis, more weight attributed to sensory evidence, due to a spontaneous or induced variable disequilibrium in the excitatory-to-inhibitory balance, predicts less proneness to visual illusions and greater vulnerability to delusional beliefs and hallucinations.

“According to this hypothesis, the more weight that is attributed to sensory evidence (because of a spontaneous or induced variable disequilibrium in the excitatory-to-inhibitory balance), the less prone the subject is to VIs, and the more vulnerable he will be to delusional beliefs and hallucinations.”

May combine two claims.

An overweighting of sensory evidence may explain both hallucinations and reduced susceptibility to visual illusions in schizophrenia.

“We effectively illustrated how an overweighting of sensory evidence may explain both hallucinations and the reduced susceptibility to VIs in schizophrenia.”

Probably not a substantial claim: may not pass S4 (based).

Hallucinations would only emerge when facing highly uncertain and normally irrelevant sensory information.

“Hallucinations would only emerge when facing highly uncertain (and normally irrelevant) sensory information.”

• AssumptionThe authors state this as an assumption: During the vast majority of daily life situations, patients resolve the moderate ambiguity of environmental stimuli through strong and unambiguous percepts but with weakened links and coherence between perceptual elements.

May combine two claims.

Studies comparing schizophrenia with bipolar or major depressive disorder found that the latter two groups were normally sensitive to Binocular depth inversion and Contrast modulation, significantly different from schizophrenia patients.

“studies that directly compared patients who suffered from schizophrenia with patients who suffered from bipolar or major depressive disorders found that the latter two groups were normally sensitive to Binocular depth inversion (Schneider et al., 2002; Koethe et al., 2009; Wang et al., 2013) and Contrast modulation (Dakin et al., 2005; Yang et al., 2013), which was significantly different from the”

• cites Schneider et al., 2002 sourceNot checked yet

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• cites Koethe et al., 2009 sourceNot checked yet

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• cites Wang et al., 2013 sourceNot checked yet

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Probably not a substantial claim: may not pass S4 (based).

This proposal may account for the gradual increase in susceptibility to visual illusions that accompanies the progressive emergence of misperceptions in some psychiatric or neurological conditions, such as Parkinson's disease.

“This proposal may account for the gradual increase in susceptibility to VIs that accompanies the progressive emergence of misperceptions in some psychiatric or neurological conditions, such as Parkinson's disease (see also Section Visual Illusions, Bayes and Psychotic Symptoms).”

May combine two claims.

The Bayesian framework predicts that false inferences provide heuristic value to vulnerability to illusions, which can be considered an indirect but valuable access to global neural processing in schizophrenia.

“provide an heuristic value to the vulnerability to illusions, which can be considered an indirect but valuable access to the global neural processing in this disorder.”

Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

This phenomenon can also be explained by the lack of prior influence on saliency.

“This phenomenon can also be explained by the lack of prior influence on saliency.”

May combine two claims.

Using a probabilistic generative model, Brown et al. predicted that a failure in attenuating sensory proprioceptive evidence led to delusional ideas regarding agency and decreased susceptibility to the Force-matching illusion.

“Using a probabilistic generative model, the authors predicted that a failure in attenuating sensory proprioceptive evidence led to the emergence of delusional ideas regarding agency (the ability to correctly identify oneself as the cause of one's own actions), as well as a decreased susceptibility to the Force-matching illusion.”

• cites Brown et al. (2013) sourceNot checked yet

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May combine two claims.

These findings are in accordance with previous experimental reports of resistance to visual illusions in schizophrenia but extend the observation to multisensory perception.

“These findings are in accordance with previous experimental reports of resistance to VIs in schizophrenia but extend this observation to multisensory perception.”

May combine two claims.

Shergill et al. indicated that schizophrenia patients were more accurate than controls when matching an externally applied force, revealing a failure in the normal sensory attenuation mechanism.

“The authors indicated that patients who suffered from schizophrenia were more accurate compared with controls when matching the externally applied force, which revealed a failure in the normal sensory attenuation mechanism.”

• cites Shergill et al., 2005 sourceNot checked yet

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