Razzak Abdul Rima, Jahrami Haitham, Husni Mariwan, Ali Maryam Ebrahim, Bagust Jeff
Department of Physiology, College of Medicine and Medical Sciences (CMMS), Arabian Gulf University (AGU), Manama, Bahrain.
Ministry of Health (MOH), Manama, Bahrain.
Front Psychiatry. 2022 Jul 18;13:948114. doi: 10.3389/fpsyt.2022.948114. eCollection 2022.
Contextual processing dysfunction in patients with schizophrenia (SCZ) is not uniform and task-dependent. In SCZ, studies on the rod and frame test (RFT), which evaluates contextual modulation of verticality perception, are sparse. A main study that utilized a two-alternative forced choice design for judging rod verticality reported equivalent strength of RFT contextual modulation in healthy controls and SCZ. The current study aims to uncover any potential differences in contextual modulation between controls and SCZ with an adjustment method on a computerized RFT.
A total of 17 healthy controls and 15 SCZ aligned an oriented rod to their perceived vertical with a computer mouse under four randomized frame presentations: absent frame, non-tilted (Frame), or tilted by 18 degrees leftward (Frame) or rightward (Frame). Rod deviation error was assigned a negative or positive value when aligned leftward or rightward, respectively, of 0°. Signed and absolute errors, the rod and frame effect (RFE), and intra-individual variability (inconsistency) were used for analysis.
There was no group difference in rod alignment errors or derived measures, except that SCZ displayed greater inconsistency in rod alignment, compared to controls. The negative symptom scale (PANSS-N) scores correlated positively with the variability measure and with unsigned Frame error.
Only the variability measure was sensitive enough to distinguish between controls and SCZ. SCZ with more severe negative symptoms had larger variability in rod alignment, probably reflecting a state of indifference. The larger deviation errors only with a leftward tilted frame, as PANSS-N scores increased, may indicate a lateralized attentional abnormality that is correlated with severity of symptoms in SCZ.
精神分裂症（SCZ）患者的情境处理功能障碍并不一致且依赖于任务。在SCZ中，关于评估垂直感知情境调制的杆框测验（RFT）的研究较少。一项主要研究采用二选一强制选择设计来判断杆的垂直度，结果显示健康对照者和SCZ患者的RFT情境调制强度相当。本研究旨在通过计算机化RFT的调整方法揭示对照者和SCZ患者在情境调制方面的潜在差异。
共有17名健康对照者和15名SCZ患者使用计算机鼠标在四种随机呈现的框架条件下将定向杆调整到他们感知的垂直方向：无框架、非倾斜（框架）、向左倾斜18度（框架）或向右倾斜18度（框架）。当杆向左或向右偏离0°时，杆偏差误差分别被赋予负值或正值。使用符号误差和绝对误差、杆框效应（RFE）以及个体内变异性（不一致性）进行分析。
除了SCZ患者在杆对齐方面表现出比对照者更大的不一致性外，两组在杆对齐误差或衍生测量方面没有差异。阴性症状量表（PANSS-N）得分与变异性测量以及无符号的框架误差呈正相关。
只有变异性测量足够敏感，能够区分对照者和SCZ患者。具有更严重阴性症状的SCZ患者在杆对齐方面具有更大的变异性，这可能反映了一种冷漠状态。随着PANSS-N得分增加，仅在向左倾斜框架时出现的更大偏差误差可能表明存在与SCZ症状严重程度相关的侧向注意力异常。
