Riba J, Valle M, Sampedro F, Rodríguez-Pujadas A, Martínez-Horta S, Kulisevsky J, Rodríguez-Fornells A
1] Human Neuropsychopharmacology Group, Sant Pau Institute of Biomedical Research (IIB-Sant Pau), Sant Antoni María Claret 167, Barcelona, Spain [2] Centre d'Investigació de Medicaments, Servei de Farmacologia Clínica, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain [3] Departament de Farmacologia i Terapèutica, Universitat Autònoma de Barcelona, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Barcelona, Spain.
1] Centre d'Investigació de Medicaments, Servei de Farmacologia Clínica, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain [2] Departament de Farmacologia i Terapèutica, Universitat Autònoma de Barcelona, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Barcelona, Spain [3] Pharmacokinetic and Pharmacodynamic Modelling and Simulation, IIB-Sant Pau, Sant Antoni María Claret, Barcelona, Spain.
Mol Psychiatry. 2015 Jun;20(6):772-7. doi: 10.1038/mp.2015.36. Epub 2015 Mar 31.
Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory memories, a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Using functional magnetic resonance imaging, we show that abstinent cannabis users have an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Furthermore, cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory. These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring.
先前关于大麻使用对神经认知影响的研究发现,工作记忆和陈述性记忆存在缺陷,这些缺陷往往会在戒断后恢复正常。慢性大麻使用者认知功能中一个尚未被探索的方面是区分真实记忆和虚幻记忆的能力,这是现实监测的一个关键方面,依赖于足够的记忆功能和认知控制。通过功能磁共振成像,我们发现戒断的大麻使用者对错误记忆的易感性增加,无法将诱发性刺激识别为从未发生过的事件。除了表现受损外,大麻使用者在与外侧和内侧颞叶(MTL)内记忆处理相关的区域,以及参与注意力和表现监测的顶叶和额叶脑区的激活减少。此外,大麻消费与MTL活动呈负相关,表明该药物对记忆的情节方面特别有害。这些发现表明,即使在戒断且无药物的情况下,大麻使用者对记忆扭曲的易感性也会增加,这表明参与现实监测的记忆和认知控制机制存在长期损害。