Martoni Riccardo Maria, Salgari Giulia, Galimberti Elisa, Cavallini Maria Cristina, O'Neill Joseph
Department of Clinical Neuroscience, San Raffaele Scientific Institute, Via Stamira D'Ancona, 20, 20127, Milan, Italy.
Division of Child and Adolescent Psychiatry, UCLA Semel Institute for Neurosciences, Los Angeles, CA, USA.
Eur Arch Psychiatry Clin Neurosci. 2015 Dec;265(8):707-18. doi: 10.1007/s00406-015-0604-2. Epub 2015 May 14.
Visuospatial working memory (VSWM) is the ability of the brain to transiently store and manipulate visual information. VSWM deficiencies have been reported in obsessive-compulsive disorder (OCD), but not consistently, perhaps due to variability in task design and clinical patient factors. To explore this variability, this study assessed effects of the design factors task difficulty and executive organizational strategy and of the clinical factors gender, OCD symptom dimension, and duration of illness on VSWM in OCD. The CANTAB spatial working memory, spatial recognition memory, delayed matching to sample, and stop signal tasks were administered to 42 adult OCD patients and 42 age- and sex-matched healthy controls. Aims were to detect a possible VSWM deficit in the OCD sample, to evaluate influences of the above task and patient factors, to determine the specificity of the deficit to the visuospatial subdomain, and to examine effects of sustained attention as potential neurocognitive confound. We confirmed previous findings of a VSWM deficit in OCD that was more severe for greater memory load (task difficulty) and that was affected by task strategy (executive function). We failed to demonstrate significant deficits in neighboring or confounding neurocognitive subdomains (visual object recognition or visual object short-term memory, sustained attention). Notably, the VSWM deficit was only significant for female patients, adding to evidence for sexual dimorphism in OCD. Again as in prior work, more severe OCD symptoms in the symmetry dimension (but no other dimension) significantly negatively impacted VSWM. Duration of illness had no significant effect on VSWM. VSWM deficits in OCD appear more severe with higher task load and may be mediated through poor task strategy. Such deficits may present mainly in female patients and in (male and female) patients with symmetry symptoms.
视觉空间工作记忆（VSWM）是大脑暂时存储和处理视觉信息的能力。强迫症（OCD）患者中已报告存在VSWM缺陷，但结果并不一致，这可能是由于任务设计和临床患者因素的变异性所致。为了探究这种变异性，本研究评估了任务难度和执行组织策略等设计因素以及性别、OCD症状维度和病程等临床因素对OCD患者VSWM的影响。对42名成年OCD患者和42名年龄及性别匹配的健康对照者进行了剑桥神经心理测试自动化成套系统（CANTAB）的空间工作记忆、空间识别记忆、延迟样本匹配和停止信号任务。目的是检测OCD样本中可能存在的VSWM缺陷，评估上述任务和患者因素的影响，确定该缺陷在视觉空间子领域的特异性，并检查持续注意力作为潜在神经认知混杂因素的影响。我们证实了先前关于OCD患者存在VSWM缺陷的研究结果，即记忆负荷越大（任务难度），缺陷越严重，且该缺陷受任务策略（执行功能）影响。我们未能在相邻或混杂的神经认知子领域（视觉物体识别或视觉物体短期记忆、持续注意力）中证明存在显著缺陷。值得注意的是，VSWM缺陷仅在女性患者中显著，这进一步证明了OCD存在性别差异。同样与先前研究一样，对称性维度（而非其他维度）中更严重的OCD症状对VSWM有显著负面影响。病程对VSWM无显著影响。OCD患者的VSWM缺陷在任务负荷较高时似乎更严重，可能是通过不良的任务策略介导的。这种缺陷可能主要出现在女性患者以及有对称性症状的（男性和女性）患者中。
