The Study Of Intertemporal Decision-Making In Moyamoya Disease

Background Moyamoya disease is a cerebrovascular disease characterized by a progressive stenosis or occlusion of the intracranial internal carotid arteries and their proximal branches,with subsequent abnormally formed collateral vessels,which not only causes ischemic cerebral infarction,cerebral hemorrhage and epilepsy but also show cognitive dysfunction in multiple domains.Intertemporal choices is a component of advanced social cognition,which is a choice to be made after evaluating the reward amount and time delay.Patients with mental illness has been widely reported to have impairment of intertemporal decision-making function.Some studies have found cognitive dysfunction in many areas,especially executive dysfunction,in patients with moyamoya disease,but whether it is combined with impaired intertemporal decision-making function has not been reported.Objective To explore whether MMD patients have declined cognitive function and impaired intertemporal decision-making function in comparison to those of healthy controls.Method This study included a total of 30 patients with moyamoya disease and 20 healthy controls who needed to match the MMD group in terms of age,gender and educational attainment.They were required to participate in a computerized version of the “Intertemporal choice” task and the“Delay-discounting” task.The intertemporal decision-making function of every participant was assessed using the proportion of the larger LL（%）option and the discount rate k value.And their cognitive function was assessed using a complete set of neuropsychological scales which can evaluate comprehensive cognitive domains.Results In comparison to HC group,the percentage of “LL” options selected in the MMD group was significantly higher in the medium and large award levels not only in now-trials but also in not-now-trials in “Intertemporal choice”task（P<0.05）.There was no significant difference between MMD group and HC group in the proportion of selected LL levels in small reward level in the Now-trials and not-now-trials（P> 0.05）.In “Delay-discounting” task,the k values for the MMD group and HC group were（0.1150±0.0968）and（0.0277±0.0359）,the difference is statistical significance（t=28.807,P<0.001）.Based on the results of the valuation task,there were no significant differences between the MMD group and HC group in three different amount difference.Besides,the results of the neuropsychological scale showed that the scores of MMD group in the AVLT-immediate,DS-back and VFT-water beginning words,all lower than the HC group（P<0.05）.But the HAMA and HAMD scores in MMD group were significantly higher than the HC group（P<0.05）.The relationship between metrics of the “Intertemporal choice” task and the“Delay-discounting” task and scores of the neuropsychological scale was studied by correlation analysis.It shows that the poor intertemporal decision-making was correlated with language and executive function impairment（P<0.05）.And the value of k was was related to executive function（P<0.01）.Conclusion The results demonstrates that MMD patients when they were not significantly impaired in early overall cognitive functions,show a decrease in their ability to make intertemporal decision,indicating that intertemporal decision-making dysfunction may be the characteristic early clinical manifestations of moyamoya disease.It was learned in the correlation analysis that the intertemporal decision-making function of MMD patients may be closely related to language and executive function.