Malik Asad, Millard Shannon N, Finlayson Ailidh, Beckenstrom Amy, Abrahams Abigail, Hernaus Dennis, Voulgaropoulou Stella D, van Amelsvoort Therese, Umbricht Daniel, Martin William J, Pemberton Darrel J, Tiller Jane, Sambeth Anke, Grimm Oliver, Plichta Michael M, Reif Andreas, Styliadis Charis, Liozidou Athanasia, Papazisis Georgios, Pérez Victor, Elices Matilde, Allebrandt Karla V, Pollentier Stephane, Dawson Gerard R
P1vital Products Ltd., Wallingford, United Kingdom.
Department of Psychiatry and Neuropsychology, Mental Health and Neuroscience (MHeNs) Research Institute, Maastricht University, Maastricht, Netherlands.
Neurosci Appl. 2025 Jul 30;4:105524. doi: 10.1016/j.nsa.2025.105524. eCollection 2025.
The aims of the Reward Task Optimisation Consortium (RTOC) study (Bilderbeck et al., 2020) were to explore the validity, reliability, and feasibility of a battery of reward processing tasks for the development of new treatments for anhedonia. We report our findings from the Grip Strength Effort Task (GSET), an effort-based decision-making task in which participants chose to either perform easy trials that required less physical effort for low monetary reward or hard trials that required more effort for potentially larger rewards. Thirty-seven participants with schizophrenia (SZ), 40 with major depressive disorder (MDD), and 59 age- and sex-matched healthy controls were administered the task across four European sites. 19% of participants (8.5% HC, 27% SZ, 27.5% MDD) were 'inflexible responders' who always chose hard trials irrespective of the reward amount. MDD participants showed less willingness to exert physical effort for high reward than controls, when inflexible responders were excluded, but no statistically significant differences were observed between SZ participants and controls. Across all participants, willingness to exert effort for high reward negatively correlated with measures of anhedonia. Inflexible responders exhibited higher depressive symptoms and higher anticipation of punishment than other participants. Forty-three participants performed the GSET again after 3-5 weeks and moderate-to-high test-retest reliability was observed. Minimal site effects confirmed operational feasibility of the task in multi-site studies. We conclude that the GSET can provide objective behavioural biomarkers of reward processing dysfunction, but further investigation is needed to understand inflexible responding and its implications on the task's design and interpretation.
奖励任务优化联盟（RTOC）研究（Bilderbeck等人，2020年）的目的是探索一系列奖励处理任务对于开发治疗快感缺乏症新疗法的有效性、可靠性和可行性。我们报告了握力努力任务（GSET）的研究结果，这是一项基于努力的决策任务，参与者可以选择进行简单试验（需要较少体力就能获得低金额奖励）或困难试验（需要更多努力才能获得可能更高的奖励）。来自四个欧洲地点的37名精神分裂症（SZ）患者、40名重度抑郁症（MDD）患者以及59名年龄和性别匹配的健康对照者参与了该任务。19%的参与者（8.5%的健康对照者、27%的精神分裂症患者、27.5%的重度抑郁症患者）是“不灵活反应者”，他们总是选择困难试验，而不管奖励金额。排除不灵活反应者后，重度抑郁症患者为获得高奖励而付出体力的意愿低于对照组，但精神分裂症患者与对照组之间未观察到统计学上的显著差异。在所有参与者中，为获得高奖励而付出努力的意愿与快感缺乏症的测量指标呈负相关。不灵活反应者比其他参与者表现出更高的抑郁症状和更高的惩罚预期。43名参与者在3至5周后再次进行了握力努力任务，观察到了中度至高的重测信度。最小的地点效应证实了该任务在多地点研究中的操作可行性。我们得出结论，握力努力任务可以提供奖励处理功能障碍的客观行为生物标志物，但需要进一步研究以了解不灵活反应及其对任务设计和解释的影响。
