Spatiotemporal Visual Processing in Schizophrenia

Kéri, Szabolcs; Antal, Andrea; Szekeres, György; Benedek, György; Janka, Zoltán

doi:10.1176/jnp.14.2.190

Cited by 99 publications

(48 citation statements)

References 42 publications

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“…The finding of an elevated critical duration for house discrimination in schizophrenia echoes well-established findings of elevated duration thresholds for more primitive objects (Slaghuis and Bakker, 1995) or letters (Saccuzzo and Braff, 1986). Deficits in contrast sensitivity have also been seen in other studies of schizophrenia Keri et al, 2002;Slaghuis, 1998). The contrast sensitivity findings as well as prolonged duration for same/different discrmination of objects confirm earlier findings of impaired early visual processing in schizophrenia (Butler et al, 2007;Butler et al, 2005;Cadenhead et al, 1998;Green et al, 1994;Keri et al, 2004;Kim et al, 2005;O'Donnell et al, 2002;Slaghuis and Thompson, 2003).…”

Section: Discussionsupporting

confidence: 85%

What's in a face? Effects of stimulus duration and inversion on face processing in schizophrenia

Butler

Tambini

Yovel

et al. 2008

Schizophrenia Research

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A number of studies show deficits in early-stage visual processing in schizophrenia. Deficits are also seen at more complex levels, such as ability to discriminate faces. This study investigated the "face inversion" effect, which reflects intrinsic cortical processing within the ventral visual stream, as well as contrast sensitivity, which reflects low-level visual processing, in order to evaluate integrity of specific stages of face processing in schizophrenia. Patients with schizophrenia and controls discriminated between pairs of upright or inverted faces or houses that had been manipulated to differ in the shape of the parts or the spatial distance among parts. The duration threshold for above chance performance on upright stimuli was obtained for patients using a house discrimination task. Contrast sensitivity was assessed for gratings of three spatial frequencies ranging from 0.5 to 21 cycles/degree. Patients needed significantly longer time to obtain 70% correct for upright stimuli and showed decreased contrast sensitivity. Increased duration threshold correlated with reduced contrast sensitivity to low (magnocellular-biased) but not medium or high spatial frequency stimuli. Using increased durations, patients showed significant inversion effects that were equivalent to those of controls on the face part and spacing tasks. Like controls, patients did not show inversion effects on the house tasks. These findings show that patients have difficulty integrating visual information as shown by increased duration thresholds. However, when faces were presented at these longer duration thresholds, patients showed the same relative processing ability for upright vs. inverted faces as controls, suggesting preserved intrinsic processing within cortical face processing regions. Similar inversion effects for face part and spacing for both groups suggest that they are using the same holistic face processing mechanism.

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Section: Discussionsupporting

confidence: 85%

What's in a face? Effects of stimulus duration and inversion on face processing in schizophrenia

Butler

Tambini

Yovel

et al. 2008

Schizophrenia Research

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“…In the visual system, deficits have been shown to include increased visual thresholds (Cadenhead et al, 1997;Schechter et al, 2003), greater sensitivity to backward masking (Braff et al, 1991;Butler et al, 1996;Green and Nuechterlein, 1999a;Schechter et al, 2003), and decreased contrast sensitivity (Butler et al, 2005;Keri et al, 2002;Slaghuis and Curran, 1999), as well as motion perception (Chen et al, 1999;Li, 2002;Schwartz et al, 1999) and eye tracking deficits (Holzman et al, 1974;Levy et al, 1993;Trillenberg et al, 2004). Further, it has been suggested that these impairments may contribute to 'upstream' cognitive and social impairments (Brenner et al, 2002;Bruder et al, 1998;Kee et al, 1998;Ohno et al, 2000;Perry and Braff, 1994;Sergi and Green, 2003) and overall functional outcome of patients (Green et al, 2000).…”

Section: Introductionmentioning

confidence: 99%

“…In contrast, more recent models subdivide into distinct magnocellular (M) vs. parvocellular (P) pathways defined based on neuroanatomy and response properties of underlying neurons with schizophrenia associated with M system underactivity on the basis of contrast sensitivity (Butler et al, 2005;Keri et al, 2002Keri et al, ,1998Slaghuis, 1998) and steady state VEPs (Butler et al, 2001(Butler et al, , 2005. Properties of M neurons correspond closely to those of the 'transient' pathway, whereas properties of the P neurons correspond to those of the sustained pathway.…”

Section: Introductionmentioning

confidence: 99%

“…Although behavioral (Butler et al, 2005;Keri et al, 2002Keri et al, , 2004O'Donnell et al, 1996O'Donnell et al, , 2002Slaghuis, 1998Slaghuis, , 2004 and steady state VEP (Butler et al, 2001(Butler et al, , 2005 studies suggest deficits in early-stage visual processing in schizophrenia particularly involving underactivity of the M system, previous studies of transient VEP (tVEP) in schizophrenia have been conflicting. Initial, as well as current, studies of the tVEP (Shagass et al, 1977;Straumanis et al, 1982;van der Stelt et al, 2004) have found no impairment in the early components of the waveform, reporting a deficit only at 200 ms (Shagass, 1980) or later (van der Stelt et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

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Impairments in generation of early-stage transient visual evoked potentials to magno- and parvocellular-selective stimuli in schizophrenia

Schechter

Butler

Zemon

et al. 2005

Clinical Neurophysiology

137

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Objective-Patients with schizophrenia demonstrate significant impairments of early visual processing, potentially implicating dysfunction of the magnocellular visual pathway. The present study evaluates transient visual evoked potential (tVEP) responses to stimuli biased toward the magnocellular (M) or parvocellular (P) systems in patients with schizophrenia vs. normal volunteers first to evaluate relative contributions of M and P systems to specific tVEP components in schizophrenia and, second, to evaluate integrity of early M and P processing in schizophrenia.Methods-Seventy-four patients with schizophrenia and schizoaffective disorder were compared with 59 control subjects using separate stimuli to assess the tVEP response to M, P and mixed M/P conditions. Stimuli were biased toward M vs. P processing by manipulation of chromatic and achromatic contrast. C1, P1, N1 and P2 components were compared between patients and controls. All subjects showed 20/32 vision or better.Results-Waveforms were obtained to low contrast (M), chromatic contrast (P) and high contrast (mixed M/P) stimuli in both patients and controls. C1 was present to P and mixed M/P stimuli. Patients showed a significant reduction in amplitude and an increase in latency of the C1 component. P1 was elicited primarily by M and mixed M/P stimuli, whereas N1 was elicited primarily by P and mixed M/P stimuli. Patients showed reductions in both P1 and N1 amplitudes across conditions. However, only reductions in P1 amplitude survived covariation for between group differences in visual acuity. Further, P1 amplitude reductions in the M condition correlated with a proxy measure of global outcome.Conclusions-M-and P-selective stimuli elicit differential components of the tVEP. Patients with schizophrenia show significant reductions in response even to simple visual stimuli. Deficits, particularly within the M system, may correlate significantly with global outcome and level of community functioning.Significance-Whereas deficits in high-order cognitive processing have been extensively documented in schizophrenia, integrity of early-stage sensory processing has been studied to a lesser degree. The present findings suggest that deficits in early-stage visual processing are significantly

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“…In the case of contrast sensitivity, a number of studies have indeed found schizophrenic individuals to have contrast sensitivity deficits which are more or less uniform across spatial and temporal frequencies (Slaghuis, 1998;Slaghuis & Bishop, 2001;Keri et al, 2002;Slaghuis, 2004;O'Donnell et al, 2006;see Skottun & Skoyles, 2007c for a review).…”

Section: Introductionmentioning

confidence: 99%