The story of memory and executive functions in obsessive-compulsive disorder: a case-control study

Abstract Objective Neuropsychological findings in obsessive-compulsive disorder (OCD) are mainly clustered around the role of memory and executive functions. However, outcomes vary across different OCD populations. In addition, the extent to which each of these factors can distinguish patients with OCD (PwOCD) from healthy individuals remains uncertain and attracts great attention. The present study aims to investigate the above issues. Method This was a cross-sectional study of 182 individuals (90 PwOCD and 92 matched healthy controls). After screening for inclusion and exclusion criteria, the participants were administered neuropsychological tests including, the Wechsler Memory Scale-III (WMS-III), the Wisconsin Card Sorting Test (WCST), and the Stroop Color-Word Test (SCWT). Data were analyzed to test the study hypotheses using comparison of means and regression analysis methods. Results The results showed that PwOCD had poorer performance than the control group in Immediate Memory, General Memory, and Working Memory and also according to response inhibition indexes. The results also showed that General Memory and Reaction Time2 from the SCWT index could be predictive variables for discriminating between PwOCD and controls. Conclusion The findings of this study support the prior assumptions that PwOCD would have impaired memory dimensions and response inhibition, but did not support worse set-shifting performance. We also present an initial model for the predictive role of these neuropsychological variables in discriminating OCD from healthy individuals and increasing diagnostic accuracy.

摘要：
研究目的：强迫症（Obsessive-Compulsive Disorder, OCD）的神经心理学研究结论主要围绕记忆与执行功能的作用展开，但不同强迫症人群的研究结果存在差异。此外，上述各项因素在区分强迫症患者（patients with OCD, PwOCD）与健康个体的有效程度仍不明确，该问题也受到学界广泛关注。本研究旨在探讨上述议题。
研究方法：本研究为横断面研究，共纳入182名受试者，其中包括90名强迫症患者与92名匹配健康对照。在筛选符合纳入与排除标准后，对受试者施测了多项神经心理学测试，涵盖韦氏记忆量表第三版（Wechsler Memory Scale-III, WMS-III）、威斯康星卡片分类测验（Wisconsin Card Sorting Test, WCST）以及斯特鲁普色词测验（Stroop Color-Word Test, SCWT）。采用均值比较与回归分析方法对数据进行分析，以验证本研究的研究假设。
研究结果：结果显示，强迫症患者在即刻记忆、总体记忆与工作记忆维度，以及反应抑制指标上的表现均劣于健康对照组。同时，斯特鲁普色词测验中的反应时2（Reaction Time2）与总体记忆指标可作为区分强迫症患者与健康对照的预测变量。
研究结论：本研究结果支持“强迫症患者存在记忆维度与反应抑制功能受损”的先前假设，但未发现其定势转换能力受损的相关证据。本研究同时构建了首个用于评估上述神经心理学变量区分强迫症与健康个体、提升诊断准确性的预测模型。