Department of Psychiatry, Ruhr-University Bochum, Alexandrinenstr. 1, 44791, Bochum, Germany.
Eur Arch Psychiatry Clin Neurosci. 2010 Sep;260(6):491-8. doi: 10.1007/s00406-010-0097-y. Epub 2010 Feb 2.
Mismatch negativity (MMN) is an auditory event-related potential indicating auditory sensory memory and information processing. The present study tested the hypothesis that chronic cannabis use is associated with deficient MMN generation. MMN was investigated in age- and gender-matched chronic cannabis users (n = 30) and nonuser controls (n = 30). The cannabis users were divided into two groups according to duration and quantity of cannabis consumption. The MMNs resulting from a pseudorandomized sequence of 2 × 900 auditory stimuli were recorded by 32-channel EEG. The standard stimuli were 1,000 Hz, 80 dB SPL and 90 ms duration. The deviant stimuli differed in duration (50 ms) or frequency (1,200 Hz). There were no significant differences in MMN values between cannabis users and nonuser controls in both deviance conditions. With regard to subgroups, reduced amplitudes of frequency MMN at frontal electrodes were found in long-term (≥8 years of use) and heavy (≥15 joints/week) users compared to short-term and light users. The results indicate that chronic cannabis use may cause a specific impairment of auditory information processing. In particular, duration and quantity of cannabis use could be identified as important factors of deficient MMN generation.
失匹配负波（MMN）是一种听觉事件相关电位，表明听觉感觉记忆和信息处理。本研究检验了慢性大麻使用与 MMN 产生缺陷相关的假设。对年龄和性别匹配的慢性大麻使用者（n=30）和非使用者对照组（n=30）进行了 MMN 测试。根据大麻使用的时间和数量，将大麻使用者分为两组。通过 32 通道 EEG 记录了由随机排列的 2×900 个听觉刺激组成的 MMN。标准刺激为 1000 Hz、80 dB SPL 和 90 ms 持续时间。在持续时间（50 ms）或频率（1200 Hz）上有偏差的刺激不同。在两种偏差条件下，大麻使用者和非使用者对照组之间的 MMN 值没有显著差异。关于亚组，与短期和轻度使用者相比，长期（≥8 年使用）和重度（≥15 关节/周）使用者的额部电极的频率 MMN 振幅降低。结果表明，慢性大麻使用可能导致听觉信息处理的特定损伤。特别是，大麻的使用时间和数量可以被确定为 MMN 产生缺陷的重要因素。
