Department of Psychology, Washington University, St. Louis, Missouri, USA.
Biol Psychiatry. 2011 Dec 15;70(12):1159-68. doi: 10.1016/j.biopsych.2011.07.010. Epub 2011 Aug 20.
Schizophrenia (SCZ) results in abnormalities affecting both working memory (WM) and emotional processing. Prior work suggests that individuals with SCZ exhibit increased effects of distraction on WM-a deficit that might be exacerbated via emotional interference. However, no study characterized effects of negative and nonemotional interference on visual WM in SCZ with functional magnetic resonance imaging. We tested the hypothesis that SCZ is associated with a general inability to filter distraction versus a specific deficit in the ability to filter aversive emotional distraction.
Twenty-eight patients with DSM-IV-diagnosed SCZ and 24 matched control subjects underwent blood-oxygen-level-dependent imaging with functional magnetic resonance imaging at 3-T. Subjects performed a modified delayed-response visual WM task faced with affectively negative, neutral, or task-related interference.
Control subjects showed maximal interference after aversive distraction, whereas patients were more distracted irrespective of interference type. Importantly, aversive distraction resulted in similar across-group activation in regions previously showing robust effects of negative interference. Conversely, after any distraction, patients showed reduced blood-oxygen-level-dependent activity in prefrontal regions previously implicated in filtering interference. Particularly when distracted, SCZ subjects exhibited aberrant responses to nonemotional distraction across posterior cortical regions.
Results suggest that patients fail to deploy activity associated with distracter filtering exhibited by control subjects. Although SCZ subjects show similar responses to aversive interference across certain regions, there is also evidence of enhanced responses to nonemotional inputs. These results are consistent with a general deficit in the ability of patients to filter distraction, which might be in line with aberrant salience processing as a pathophysiological mechanism in SCZ.
精神分裂症（SCZ）导致影响工作记忆（WM）和情绪处理的异常。先前的研究表明，精神分裂症患者表现出 WM 分心效应增加，这种缺陷可能通过情绪干扰而加剧。然而，没有研究使用功能磁共振成像来描述精神分裂症患者负性和非情绪干扰对视觉 WM 的影响。我们检验了以下假设：精神分裂症患者与普遍无法过滤分心有关，而不是与特定的回避情绪分心的能力缺陷有关。
28 名符合 DSM-IV 诊断标准的精神分裂症患者和 24 名匹配的对照受试者在 3-T 磁共振成像仪上进行了血氧水平依赖成像。受试者进行了改良的延迟反应视觉 WM 任务，同时面临负性情绪、中性或任务相关的干扰。
对照受试者在出现负性分心时表现出最大的干扰，而患者则无论干扰类型如何都表现出更多的分心。重要的是，负性分心导致了在先前显示出对负性干扰有强烈影响的区域中出现相似的组间激活。相反，在受到任何干扰后，患者在前额叶区域的血氧水平依赖活动减少，而这些区域先前被认为与过滤干扰有关。特别是在分心时，精神分裂症患者在整个后皮质区域表现出对非情绪干扰的异常反应。
结果表明，患者无法调动对照组受试者表现出的与分心过滤相关的活动。尽管精神分裂症患者在某些区域对负性干扰表现出相似的反应，但也有证据表明对非情绪输入的反应增强。这些结果与患者普遍缺乏过滤分心的能力一致，这可能与精神分裂症作为一种病理生理学机制的异常突显处理相一致。
