Salamone John D, Yohn Samantha E, López-Cruz Laura, San Miguel Noemí, Correa Mercè
Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA
Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA.
Brain. 2016 May;139(Pt 5):1325-47. doi: 10.1093/brain/aww050.
Motivation has been defined as the process that allows organisms to regulate their internal and external environment, and control the probability, proximity and availability of stimuli. As such, motivation is a complex process that is critical for survival, which involves multiple behavioural functions mediated by a number of interacting neural circuits. Classical theories of motivation suggest that there are both directional and activational aspects of motivation, and activational aspects (i.e. speed and vigour of both the instigation and persistence of behaviour) are critical for enabling organisms to overcome work-related obstacles or constraints that separate them from significant stimuli. The present review discusses the role of brain dopamine and related circuits in behavioural activation, exertion of effort in instrumental behaviour, and effort-related decision-making, based upon both animal and human studies. Impairments in behavioural activation and effort-related aspects of motivation are associated with psychiatric symptoms such as anergia, fatigue, lassitude and psychomotor retardation, which cross multiple pathologies, including depression, schizophrenia, and Parkinson's disease. Therefore, this review also attempts to provide an interdisciplinary approach that integrates findings from basic behavioural neuroscience, behavioural economics, clinical neuropsychology, psychiatry, and neurology, to provide a coherent framework for future research and theory in this critical field. Although dopamine systems are a critical part of the brain circuitry regulating behavioural activation, exertion of effort, and effort-related decision-making, mesolimbic dopamine is only one part of a distributed circuitry that includes multiple neurotransmitters and brain areas. Overall, there is a striking similarity between the brain areas involved in behavioural activation and effort-related processes in rodents and in humans. Animal models of effort-related decision-making are highly translatable to humans, and an emerging body of evidence indicates that alterations in effort-based decision-making are evident in several psychiatric and neurological disorders. People with major depression, schizophrenia, and Parkinson's disease show evidence of decision-making biases towards a lower exertion of effort. Translational studies linking research with animal models, human volunteers, and clinical populations are greatly expanding our knowledge about the neural basis of effort-related motivational dysfunction, and it is hoped that this research will ultimately lead to improved treatment for motivational and psychomotor symptoms in psychiatry and neurology.
动机被定义为生物体调节其内部和外部环境，并控制刺激的可能性、接近性和可获得性的过程。因此，动机是一个对生存至关重要的复杂过程，它涉及由许多相互作用的神经回路介导的多种行为功能。经典的动机理论表明，动机既有方向性方面，也有激活方面，而激活方面（即行为的激发和持续的速度与活力）对于使生物体能够克服将它们与重要刺激隔离开的与工作相关的障碍或限制至关重要。本综述基于动物和人类研究，讨论了脑多巴胺及相关回路在行为激活、工具性 行为中的努力付出以及与努力相关的决策中的作用。行为激活和动机中与努力相关方面的损伤与诸如无力、疲劳、倦怠和精神运动迟缓等精神症状相关，这些症状跨越多种疾病，包括抑郁症、精神分裂症和帕金森病。因此，本综述还试图提供一种跨学科方法，整合基础行为神经科学、行为经济学、临床神经心理学、精神病学和神经病学的研究结果，为这一关键领域的未来研究和理论提供一个连贯的框架。虽然多巴胺系统是调节行为激活、努力付出和与努力相关决策的脑回路的关键部分，但中脑边缘多巴胺只是包括多种神经递质和脑区的分布式回路的一部分。总体而言，啮齿动物和人类中涉及行为激活和与努力相关过程的脑区之间存在显著相似性。与努力相关的决策的动物模型具有很高的人类可转化性，并且越来越多的证据表明，基于努力的决策改变在几种精神和神经疾病中很明显。患有重度抑郁症、精神分裂症和帕金森病的人表现出决策偏向于较低努力付出的证据。将研究与动物模型、人类志愿者和临床人群联系起来的转化研究正在极大地扩展我们对与努力相关的动机功能障碍的神经基础的认识，希望这项研究最终将改善精神病学和神经病学中动机和精神运动症状的治疗。
