Department of Psychology, Vanderbilt University, Nashville TN, USA ; School of Optometry, University of California Berkeley, Berkeley CA, USA.
Front Psychol. 2013 Aug 30;4:569. doi: 10.3389/fpsyg.2013.00569. eCollection 2013.
Anomalous perception has been investigated extensively in schizophrenia, but it is unclear whether these impairments are specific to schizophrenia or extend to other psychotic disorders. Recent studies of visual context processing in schizophrenia (Tibber et al., 2013; Yang et al., 2013) point to circumscribed, task-specific abnormalities. Here we examined visual contextual processing across a comprehensive set of visual tasks in individuals with bipolar disorder and compared their performance with that of our previously published results from schizophrenia and healthy participants tested on those same tasks. We quantified the degree to which the surrounding visual context alters a center stimulus' appearance for brightness, size, contrast, orientation and motion. Across these tasks, healthy participants showed robust contextual effects, as indicated by pronounced misperceptions of the center stimuli. Participants with bipolar disorder showed contextual effects similar in magnitude to those found in healthy participants on all tasks. This result differs from what we found in schizophrenia participants (Yang et al., 2013) who showed weakened contextual modulations of contrast but intact contextual modulations of perceived luminance and size. Yet in schizophrenia participants, the magnitude of the contrast illusion did not correlate with symptom measures. Performance on the contrast task by the bipolar disorder group also could not be distinguished from that of the schizophrenia group, and this may be attributed to the result that bipolar patients who presented with greater manic symptoms showed weaker contrast modulation. Thus, contrast gain control may be modulated by clinical state in bipolar disorder. Stronger motion and orientation context effects correlated with worse clinical symptoms across both patient groups and especially in schizophrenia participants. These results highlight the complexity of visual context processing in schizophrenia and bipolar disorder.
异常知觉在精神分裂症中得到了广泛研究，但目前尚不清楚这些障碍是精神分裂症特有的，还是扩展到其他精神病障碍。最近对精神分裂症中视觉语境处理的研究（Tibber 等人，2013；Yang 等人，2013）表明存在特定于任务的局限性异常。在这里，我们在一组全面的视觉任务中检查了双相情感障碍个体的视觉语境处理，并将他们的表现与我们之前在相同任务中测试的精神分裂症和健康参与者的研究结果进行了比较。我们量化了周围视觉语境改变中心刺激亮度、大小、对比度、方向和运动的程度。在这些任务中，健康参与者表现出强烈的语境效应，表现为对中心刺激的明显误解。双相情感障碍患者在所有任务中表现出与健康参与者相似的语境效应。这一结果与我们在精神分裂症患者中发现的结果不同（Yang 等人，2013），他们表现出对比度的语境调制减弱，但感知亮度和大小的语境调制完整。然而，在精神分裂症患者中，对比度错觉的幅度与症状测量值无关。双相情感障碍组在对比度任务上的表现也无法与精神分裂症组区分开来，这可能归因于出现更多躁狂症状的双相情感障碍患者表现出较弱的对比度调制的结果。因此，在双相情感障碍中，对比度增益控制可能受到临床状态的调节。在两个患者组中，更强的运动和方向语境效应与更严重的临床症状相关，尤其是在精神分裂症患者中。这些结果突出了精神分裂症和双相情感障碍中视觉语境处理的复杂性。
