Neuroscience and Psychiatry Unit, University of Manchester Manchester, UK.
Front Integr Neurosci. 2012 Nov 7;6:101. doi: 10.3389/fnint.2012.00101. eCollection 2012.
Substance dependence is complex and multifactorial, with many distinct pathways involved in both the development and subsequent maintenance of addictive behaviors. Various cognitive mechanisms have been implicated, including impulsivity, compulsivity, and impaired decision-making. These mechanisms are modulated by emotional processes, resulting in increased likelihood of initial drug use, sustained substance dependence, and increased relapse during periods of abstinence. Emotional traits, such as sensation-seeking, are risk factors for substance use, and chronic drug use can result in further emotional dysregulation via effects on reward, motivation, and stress systems. We will explore theories of hyper and hypo sensitivity of the brain reward systems that may underpin motivational abnormalities and anhedonia. Disturbances in these systems contribute to the biasing of emotional processing toward cues related to drug use at the expense of natural rewards, which serves to maintain addictive behavior, via enhanced drug craving. We will additionally focus on the sensitization of the brain stress systems that result in negative affect states that continue into protracted abstinence that is may lead to compulsive drug-taking. We will explore how these emotional dysregulations impact upon decision-making controlled by goal-directed and habitual action selections systems, and, in combination with a failure of prefrontal inhibitory control, mediate maladaptive decision-making observed in substance dependent individuals such that they continue drug use in spite of negative consequences. An understanding of the emotional impacts on cognition in substance dependent individuals may guide the development of more effective therapeutic interventions.
物质依赖是复杂的多因素的,涉及许多不同的途径,包括成瘾行为的发展和随后的维持。各种认知机制都与成瘾行为有关,包括冲动性、强迫性和决策能力受损。这些机制受情绪过程的调节,导致初始药物使用的可能性增加、物质依赖的持续存在以及在禁欲期间复发的可能性增加。情绪特质,如寻求刺激,是物质使用的风险因素,慢性药物使用会通过对奖励、动机和应激系统的影响导致进一步的情绪失调。我们将探讨大脑奖励系统的超敏和低敏理论,这些理论可能是动机异常和快感缺失的基础。这些系统的紊乱导致对与药物使用相关的线索的情绪处理产生偏见,而牺牲了自然奖励,从而维持成瘾行为,通过增强药物渴望来实现。我们还将重点关注大脑应激系统的敏感化,导致消极情绪状态持续到长期禁欲,这可能导致强迫性药物滥用。我们将探讨这些情绪失调如何影响由目标导向和习惯性行动选择系统控制的决策,并与前额叶抑制控制的失败相结合,介导物质依赖个体中观察到的适应不良决策,从而导致他们不顾负面后果继续使用药物。了解物质依赖个体的情绪对认知的影响可能有助于指导更有效的治疗干预措施的发展。