Sensory Processing Deficits in Cannabis Use

描述（由申请人提供）：众所周知，使用大麻药物会导致几种感觉模式的主观知觉扭曲。然而，很少直接检查大麻使用对早期感觉处理的神经影响，特别是利用新的电生理技术。当前提案的总体目标是检查当前大麻使用者是否表现出神经同步缺陷，这是通过脑电图（EEG）对周期性听觉和视觉刺激的干扰来测量的。受试者将被动地观察周期性的感官刺激(听觉点击训练（10、20、30、40和50 Hz）和光闪烁（8、13、18、25和38 Hz），同时记录脑电图。由此产生的稳态电位与特定刺激频率同步的能力将通过脑电图功率、信噪比和试验间相干性来评估。此外，在感知绑定期间的脑电图同步将利用诱导伽马范式（使用随机点活动图移动点刺激）进行评估。还将进行几次临床访谈和心理测量问卷调查，以确定脑电图脑测量与大麻使用的感知相关性之间可能存在的关系。假设在夹带范式中，大麻使用者在不同感觉模态的刺激频率下会表现出EEG功率、信噪比和试验间相干性的下降。研究还预测，在诱导脑电图范式中，大麻使用者在感知相干移动点期间会表现出γ波段（~ 40 Hz）活动的减少。据推测，脑电图神经同步的这些缺陷将与心理测量指标相关，如分裂型人格和知觉畸变，以及尿液中大麻代谢物的测量。综上所述，这些数据可能有助于阐明大麻使用中观察到的已知认知功能障碍是否部分与早期感觉信息处理和/或神经同步的干扰有关。

DESCRIPTION (provided by applicant): It is well known that use of the drug cannabis can induce subjective distortions of perception in several sensory modalities. However, few direct examinations of the neural effects of cannabis use on early sensory processing have been undertaken, particularly utilizing novel electrophysiological techniques. The overall aim of the current proposal is to examine whether current cannabis users demonstrate deficits in neural synchronization as measured by electroencephalographic (EEG) entrainment to periodic auditory and visual stimulation. Subjects will passively observe periodic sensory stimuli (auditory click-trains (10, 20, 30, 40, and 50 Hz) and photic flickers (8, 13, 18, 25, and 38 Hz) while EEGs are recorded. The ability of the resulting steady-state potentials to synchronize to the specific frequencies of stimulation will be assessed via EEG power, signal to noise ratio, and intertrial coherence. In addition, EEG synchronization during perceptual binding will be assessed utilizing an induced gamma paradigm (moving dot stimuli using Random Dot Kinetograms). Several clinical interviews and psychometric questionnaires will also be administered in order to determine possible relationships between EEG brain measures and the perceptual correlates of cannabis use. It is hypothesized that during the entrainment paradigms cannabis users will exhibit decreased EEG power, signal to noise ratio, and intertrial coherence at the frequencies of stimulation across sensory modalities. It is also predicted that during the induced EEG paradigm, cannabis users will exhibit decreased gamma-band (~ 40 Hz) activity during the perception of coherent moving dots. It is hypothesized that these deficits in EEG neural synchronization will correlate with psychometric measures such as schizotypal personality and perceptual aberration, as well as urinary measures of cannabis metabolites. Taken together, this data may serve to elucidate whether the known cognitive dysfunction observed in cannabis use is in part related to disturbances in early sensory information processing and/or neural synchronization.