METHODS: In this study, we employed delay and effort-discounting tasks with food rewards in thirty-nine participants divided into high and low levels of PS. We investigated the underlying mechanisms of effort-discounting through computational modelling of dopamine prefrontal and subcortical circuits and the electrophysiological biomarker of both delay and effort-discounting alterations through resting-state frontal alpha asymmetry (FAA).
RESULTS: Results revealed greater delay discounting in the High PS group compared to the Low PS group but no differences in the effort discounting task. However, in this task, the same levels of estimated dopamine release were associated with a lower willingness to exert effort for high-calorie food rewards in High PS participants compared to Low PS participants. Although there were no significant differences in FAA between the High PS and Low PS groups, FAA was significantly associated with the severity of participants\' negative symptoms.
CONCLUSIONS: Our study suggests that the dysfunction in temporal and effort cost computations, seen in patients with schizophrenia, may be present in individuals with subclinical PS. These findings provide valuable insight into the early vulnerability markers (behavioral, computational, and electrophysiological) for psychosis, which may aid in the development of preventive interventions. These findings are preliminary and warrant further investigation.
方法:在本研究中,我们在39名参与者中采用了带有食物奖励的延迟和努力折扣任务,这些参与者的PS水平分为高和低.我们通过多巴胺前额叶和皮层下回路的计算模型以及通过静息状态额叶α不对称(FAA)的延迟和工作量折扣改变的电生理生物标志物,研究了工作量折扣的潜在机制。
结果:结果显示,与低PS组相比,高PS组的延迟折扣更大,但工作量折扣任务没有差异。然而,在这项任务中,与低PS参与者相比,在高PS参与者中,相同水平的多巴胺释放估计值与努力获得高热量食物奖励的意愿较低相关.尽管高PS和低PS组之间的FAA没有显着差异,FAA与参与者阴性症状的严重程度显著相关。
结论:我们的研究表明,时间和努力的功能障碍需要计算,在精神分裂症患者中看到,可能存在于亚临床PS患者中。这些发现为早期脆弱性标记(行为,计算,和电生理学)用于精神病,这可能有助于预防干预措施的发展。这些发现是初步的,需要进一步调查。