【作者】 秦幸娜； 李新旺；

【Author】 Qin xingna~1;LI Xin-Wang~2 (Capital Normal University,Beijing 100048,China)

【机构】 首都师范大学心理学系；

【摘要】 冲动性是对刺激的不良构思、过早表达、不当冒险或者不适当反应并且常导致不良后果的行为,过高水平的冲动是ADHD、药物滥用以及精神分裂症等一些常见精神疾病的主要症状。冲动性具有多结构、多维度性是研究者所普遍认可的,但是目前尚存在着二维、三维和四维的结构之争,本文以冲动性的二维结构为理论依据,将冲动性分为冲动动作和冲动选择。冲动动作即在行为层面上不能抑制自己的动作,是指一个已经发起的动作是否能够得到抑制;冲动决策即在认知层面上不能正确评估信息,也被理解为不能延迟满足或者不愿接受发生可能性较小的事物。研究者们采用多种动物实验范式,试图解释冲动性的生理基础及其神经机制,5项选择序列反应时任务、延迟折扣和概率折扣任务是当今研究冲动行为与冲动决策的主要动物模型。研究者在这些研究范式的基础上已经取得了丰富的研究成果,相关的研究表明前额叶、纹状体等脑结构通过神经递质系统对冲动性进行调节。目前,学者们认为冲动性与动机、决策等相关的神经通路有关,过高水平冲动可能是前额叶边缘系统纹状体及其三者形成的神经回路中多巴胺、去甲肾上素、五羟色胺以及乙酰胆碱等神经化学物质的功能紊乱引起的。但是,脑结构、神经递质系统和环境因素如何交互作用以及在何种水平上影响冲动性等这些问题目前尚不清楚。因此,在今后的研究中,需要更加注意环境因素、基因以及神经化学物质对冲动性影响的研究。更多还原

【Abstract】 Impulsivity is broadly defined as actions that are poorly conceived,prematurely expressed,unduly risky,or inappropriate to the situation and that often result in undesirable outcomes.Higher impulsivity is observed in several psychiatric disorders such as attention-deficit/hyperactivity disorder(ADHD),drug abuse,and schizophrenia.Although researchers argue that several dimensions of impulsivity exist,that is two or three or four dimensions,the multiple dimensions of impulsivity are generally recognized.In this review,we based on the theory of two-dimensional structures of impulsivity,which is divided into impulsive action and impulsive choice. Impulsive action is a failure of motor inhibition,which includes a failure to stop/cancel an action after it has begun. Impulsive choice is either the tendency to choose small,immediately rewards instead of large,delayed ones or the tendency to choose likely rewards instead of unlikely ones.Investigation of the neuropsychological basis of the impulsivity has been greatly aided by the fact that there are varieties of means for measuring impulsive behavior in animal.5-choice serial reaction time task is mainly for impulsive action,delay discounting task and probability discounting task are mainly for impulsive choice.Evidences is surveyed that cortical and subcortical mechanisms such as prefrontal cortex and striatum are implicated in the impulsivity by neurochemical systems.Recently,the neural substrates of impulsivity are mainly associated with the neural circuitry of motivation and decision-making. Moreover,the possibility exists for higher impulsivity to be caused by a dysfunctioning of fronto-limbic-striatal circuitries and the level of dopamine,noradrenaline,serotonin and acetylcholine.However,it is still unclear that how and to what level brain structures,neurotransmitter systems and environmental factors interact with each other and affect the impulsivity.Some of the key questions remaining are the origins,genetic and neurochemical level of impulsivity as well as the environmental factors.更多还原