Department of Life Sciences, Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, USA.
Schizophr Bull. 2009 Nov;35(6):1085-94. doi: 10.1093/schbul/sbp100. Epub 2009 Sep 30.
Deficits in early visual processing are well documented in schizophrenia, using methods such as contrast sensitivity. Higher, integrative stages of functioning, such as susceptibility to visual illusions, have been evaluated less extensively. For example, patients show increased susceptibility to (ie, are more easily affected by) the Muller-Lyer illusion but decreased susceptibility (ie, are less easily affected by) to stereopsis based upon binocular disparity. The basis for pattern of illusion response and interaction between sensory and integrative stages of processing, however, is unclear. We tested a group of 38 patients and 28 control subjects in contrast sensitivity, the Muller-Lyer and Poggendorff illusions, as well as a subgroup in stereopsis and the Ponzo illusion, Sander parallelogram, and Hermann grid illusions. We predicted that patients would be more susceptible to tests that become more apparent with increased contrast (Muller-Lyer illusion), less susceptible to tests that become less apparent with increased contrast (stereopsis, Ponzo illusion, Hermann grid), and equally susceptible to contrast-insensitive tests (Poggendorff illusion). Additionally, the Hermann grid was tested at varying levels of contrast. Patients demonstrated significant deficits in contrast sensitivity, especially to brief, low spatial frequency stimuli, and the predicted differential response to the tested illusions. Additionally, poor performance on stereopsis and the Hermann grid significantly correlated with decreased contrast sensitivity (all P's <.01). Muller-Lyer illusion and stereopsis performance were also inversely related (P < .01). This study replicates and expands upon previous findings with visual illusions. Our results offer a unifying explanation for disparate studies and suggest that deficits in early sensory gain affect subsequent integrative processes.
精神分裂症患者的早期视觉处理存在缺陷，这可以通过对比敏感度等方法得到证明。而对于更高阶、综合功能的阶段，如易受视觉错觉影响的程度，评估则相对较少。例如，患者更容易受到（即更容易受到影响）Muller-Lyer 错觉的影响，但对基于双眼视差的立体视敏度的易感性降低（即，不易受到影响）。然而，对于错觉反应的模式和感觉与综合处理阶段之间的相互作用的基础，目前尚不清楚。我们测试了一组 38 名患者和 28 名对照者的对比敏感度、Muller-Lyer 和 Poggendorff 错觉，以及一小部分人的立体视和 Ponzo 错觉、Sander 平行四边形和 Hermann 网格错觉。我们预测，患者在对比度增加时会更容易受到测试的影响（Muller-Lyer 错觉），而在对比度增加时会更不容易受到测试的影响（立体视、Ponzo 错觉、Hermann 网格），并且对对比度不敏感的测试（Poggendorff 错觉）的易感性相同。此外，Hermann 网格在不同对比度水平下进行了测试。患者在对比敏感度方面表现出明显的缺陷，尤其是在短暂、低空间频率刺激下，并且对测试的错觉表现出预期的差异反应。此外，立体视和 Hermann 网格的表现不佳与对比敏感度降低显著相关（均 P <.01）。Muller-Lyer 错觉和立体视表现也呈负相关（P <.01）。本研究复制并扩展了以前关于视觉错觉的研究结果。我们的结果为不同的研究提供了一个统一的解释，并表明早期感觉增益的缺陷会影响后续的综合处理过程。
