Attention and Masking in Schizophrenia

Lalanne, Laurence; Dufour, André; Després, Olivier; Giersch, Anne

doi:10.1016/j.biopsych.2011.09.018

Cited by 17 publications

(11 citation statements)

References 46 publications

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“…However, the McGurk effect relies on implicit multisensory binding, while judgments of temporal asynchrony are precisely explicit. Differences in the preservation of these capabilities are expected in light of the independence of implicit and explicit judgments and previously-observed differences in their impairment in schizophrenia (Lalanne et al, 2012a,b). Furthermore, irrespective of the conceptual independence of these judgment types, reduced susceptibility to illusions and reduced performance in temporal asynchrony tasks can be reasonably interpreted as deviation from the behavior of an optimal observer.…”

Section: Discussionmentioning

confidence: 88%

Eluding the illusion? Schizophrenia, dopamine and the McGurk effect

White

Wigton

Joyce

et al. 2014

Front. Hum. Neurosci.

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Perceptions are inherently probabilistic; and can be potentially manipulated to induce illusory experience by the presentation of ambiguous or improbable evidence under selective (spatio-temporal) constraints. Accordingly, perception of the McGurk effect, by which individuals misperceive specific incongruent visual and auditory vocal cues, rests upon effective probabilistic inference. Here, we report findings from a behavioral investigation of illusory perception and related metacognitive evaluation during audiovisual integration, conducted in individuals with schizophrenia (n = 30) and control subjects (n = 24) matched in terms of age, sex, handedness and parental occupation. Controls additionally performed the task after an oral dose of amisulpride (400 mg). Individuals with schizophrenia were observed to exhibit illusory perception less frequently than controls, despite non-significant differences in perceptual performance during control conditions. Furthermore, older individuals with schizophrenia exhibited reduced rates of illusory perception. Subsequent analysis revealed a robust inverse relationship between illness chronicity and the illusory perception rate in this group. Controls demonstrated non-significant modulation of perception by amisulpride; amisulpride was, however, found to elicit increases in subjective confidence in perceptual performance. Overall, these findings are consistent with the idea that impairments in probabilistic inference are exhibited in schizophrenia and exacerbated by illness chronicity. The latter suggests that associated processes are a potentially worthwhile target for therapeutic intervention.

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Section: Discussionmentioning

confidence: 88%

Eluding the illusion? Schizophrenia, dopamine and the McGurk effect

White

Wigton

Joyce

et al. 2014

Front. Hum. Neurosci.

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“…The authors interpreted their findings as showing that patients’ feedforward processing during masking was intact whereas conscious processing of those stimuli are dysfunctional. Also, Lalanne et al (2012) suggested that backward masking impairments in schizophrenia patients may be due to a lack of focused attention on the target. Finally, using pupillometry during a backward masking task, Granholm et al (2009) found that impaired performance in patients was attributable to abnormalities in attentional resource availability.…”

Section: Discussionmentioning

confidence: 99%

Object Substitution Masking in Schizophrenia: An Event-Related Potential Analysis

et al. 2013

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Schizophrenia patients exhibit deficits on visual processing tasks, including visual backward masking, and these impairments are related to deficits in higher-level processes. In the current study we used electroencephalography techniques to examine successive stages and pathways of visual processing in a specialized masking paradigm, four-dot masking, which involves masking by object substitution. Seventy-six schizophrenia patients and 66 healthy controls had event-related potentials (ERPs) recorded during four-dot masking. Target visibility was manipulated by changing stimulus onset asynchrony (SOA) between the target and mask, such that performance decreased with increasing SOA. Three SOAs were used: 0, 50, and 100 ms. The P100 and N100 perceptual ERPs were examined. Additionally, the visual awareness negativity (VAN) to correct vs. incorrect responses, an index of reentrant processing, was examined for SOAs 50 and 100 ms. Results showed that patients performed worse than controls on the behavioral task across all SOAs. The ERP results revealed that patients had significantly smaller P100 and N100 amplitudes, though there was no effect of SOA on either component in either group. In healthy controls, but not patients, N100 amplitude correlated significantly with behavioral performance at SOAs where masking occurred, such that higher accuracy correlated with a larger N100. Healthy controls, but not patients, exhibited a larger VAN to correct vs. incorrect responses. The results indicate that the N100 appears to be related to attentional effort in the task in controls, but not patients. Considering that the VAN is thought to reflect reentrant processing, one interpretation of the findings is that patients’ lack of VAN response and poorer performance may be related to dysfunctional reentrant processing.

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“…However, a recent study showed that patients' performance in backward masking is identical to that of controls when targets are presented in both hemifields (Lalanne et al, 2012). Lastly (Fig.…”

Section: Patients Controlsmentioning

confidence: 95%