UNASSIGNED: We used magnetoencephalography (MEG) and an established visuospatial processing task to elicit multi-spectral neuronal responses in 44 regular cannabis users and 53 demographically matched non-user controls. To examine the effects of chronic cannabis use on the oscillatory dynamics underlying visuospatial processing, neural responses were imaged using a time-frequency resolved beamformer and compared across groups.
UNASSIGNED: Neuronal oscillations serving visuospatial processing were identified in the theta (4-8 Hz), alpha (8-14 Hz), and gamma range (56-76 Hz), and these were imaged and examined for group differences. Our key results indicated that users exhibited weaker theta oscillations in occipital and cerebellar regions and weaker gamma responses in the left temporal cortices compared to non-users. Lastly, alpha oscillations did not differ, but alpha connectivity among higher-order attention areas was weaker in cannabis users relative to non-users and correlated with performance.
UNASSIGNED: Overall, these results suggest that chronic cannabis users have alterations in the oscillatory dynamics and neural connectivity serving visuospatial attention. Such alterations were observed across multiple cortical areas critical for higher-order processing and may reflect compensatory activity and/or the initial emergence of aberrant dynamics. Future work is needed to fully understand the implications of altered multispectral oscillations and neural connectivity in cannabis users.
■我们使用脑磁图(MEG)和已建立的视觉空间处理任务,在44名常规大麻使用者和53名人口统计学匹配的非使用者对照中引起多光谱神经元反应。为了检查长期使用大麻对视觉空间处理潜在的振荡动力学的影响,使用时频分辨波束形成器对神经反应进行成像,并进行组间比较.
■在θ(4-8Hz)中识别出服务于视觉空间处理的神经元振荡,阿尔法(8-14赫兹),和伽马范围(56-76Hz),并对这些图像进行成像和组间差异检查。我们的关键结果表明,与非用户相比,用户在枕骨和小脑区域表现出较弱的theta振荡,而在左颞骨皮层中表现出较弱的伽马响应。最后,阿尔法振荡没有区别,但是,相对于非使用者,大麻使用者的高阶关注区域之间的alpha连通性较弱,并且与性能相关。
■总的来说,这些结果表明,慢性大麻使用者在提供视觉空间注意力的振荡动力学和神经连接方面有改变.在对高阶处理至关重要的多个皮质区域中观察到此类改变,并且可能反映出代偿活动和/或异常动力学的初始出现。需要进一步的工作来充分了解大麻使用者中改变的多光谱振荡和神经连通性的影响。