Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, Nebraska, USA.
College of Medicine, University of Nebraska Medical Center (UNMC), Omaha, Nebraska, USA.
Hum Brain Mapp. 2021 Nov;42(16):5446-5457. doi: 10.1002/hbm.25634. Epub 2021 Aug 31.
People with HIV (PWH) use cannabis at a higher rate than the general population, but the influence on neural activity is not well characterized. Cannabis use among PWH may have a beneficial effect, as neuroinflammation is known to be a critical problem in PWH and cannabis use has been associated with a reduction in proinflammatory markers. Thus, it is important to understand the net impact of cannabis use on brain and cognitive function in PWH. In this study, we collected magnetoencephalographic (MEG) brain imaging data on 81 participants split across four demographically matched groups (i.e., PWH using cannabis, controls using cannabis, non-using PWH, and non-using controls). Participants completed a visuospatial processing task during MEG. Time-frequency resolved voxel time series were extracted to identify the dynamics of oscillatory and pre-stimulus baseline neural activity. Our results indicated strong theta (4-8 Hz), alpha (10-16 Hz), and gamma (62-72 Hz) visual oscillations in parietal-occipital brain regions across all participants. PWH exhibited significant behavioral deficits in visuospatial processing, as well as reduced theta oscillations and elevated pre-stimulus gamma activity in visual cortices, all of which replicate prior work. Strikingly, chronic cannabis use was associated with a significant reduction in pre-stimulus gamma activity in the visual cortices, such that PWH no longer statistically differed from controls. These results provide initial evidence that cannabis use may normalize some neural aberrations in PWH. This study fills an important gap in understanding the impact of cannabis use on brain and cognitive function in PWH.
HIV 感染者（PWH）的大麻使用率高于一般人群，但大麻对神经活动的影响尚未得到很好的描述。PWH 中使用大麻可能有有益的效果，因为众所周知，神经炎症是 PWH 的一个关键问题，而大麻的使用与促炎标志物的减少有关。因此，了解大麻使用对 PWH 的大脑和认知功能的净影响非常重要。在这项研究中，我们收集了 81 名参与者的脑磁图（MEG）脑成像数据，这些参与者分为四个在人口统计学上匹配的组（即使用大麻的 PWH、使用大麻的对照组、不使用大麻的 PWH 和不使用大麻的对照组）。参与者在 MEG 期间完成了视觉空间处理任务。提取时频分辨体素时间序列以识别振荡和刺激前基线神经活动的动力学。我们的结果表明，所有参与者的顶枕叶脑区均存在强烈的 theta（4-8 Hz）、alpha（10-16 Hz）和 gamma（62-72 Hz）视觉振荡。PWH 在视觉空间处理方面表现出明显的行为缺陷，以及视觉皮质中的 theta 振荡减少和刺激前 gamma 活动升高，这些都与先前的工作一致。引人注目的是，慢性大麻使用与视觉皮质中刺激前 gamma 活动的显著降低有关，以至于 PWH 不再在统计学上与对照组有区别。这些结果提供了初步证据，表明大麻使用可能使 PWH 的一些神经异常正常化。这项研究填补了理解大麻使用对 PWH 的大脑和认知功能影响的重要空白。
