Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 988422 Nebraska Medical Center, Omaha, NE 68198, USA.
J Neuroimmune Pharmacol. 2013 Sep;8(4):965-74. doi: 10.1007/s11481-013-9477-1. Epub 2013 Jun 9.
Despite the availability of combination antiretroviral therapy, at least mild cognitive dysfunction is commonly observed in HIV-infected patients, with an estimated prevalence of 35-70 %. Neuropsychological studies of these HIV-associated neurocognitive disorders (HAND) have documented aberrations across a broad range of functional domains, although the basic pathophysiology remains unresolved. Some of the most common findings have been deficits in fine motor control and reduced psychomotor speed, but to date no neuroimaging studies have evaluated basic motor control in HAND. In this study, we used magnetoencephalography (MEG) to evaluate the neurophysiological processes that underlie motor planning in older HIV-infected adults and a matched, uninfected control group. MEG is a noninvasive and direct measure of neural activity with good spatiotemporal precision. During the MEG recording, participants fixated on a central crosshair and performed a finger-tapping task with the dominant hand. All MEG data was corrected for head movements, preprocessed, and imaged in the time-frequency domain using beamforming methodology. All analyses focused on the pre-movement beta desynchronization, which is known to be an index of movement planning. Our results demonstrated that HIV-1-infected patients have deficient beta desynchronization relative to controls within the left/right precentral gyri, and the supplementary motor area. In contrast, HIV-infected persons showed abnormally strong beta responses compared to controls in the right dorsolateral prefrontal cortex and medial prefrontal areas. In addition, the amplitude of beta activity in the primary and supplementary motor areas correlated with scores on the Grooved Pegboard test in HIV-infected adults. These results demonstrate that primary motor and sensory regions may be particularly vulnerable to HIV-associated damage, and that prefrontal cortices may serve a compensatory role in maintaining motor performance levels in infected patients.
尽管有联合抗逆转录病毒疗法，HIV 感染者中至少会出现轻度认知功能障碍，其估计患病率为 35-70%。对这些与 HIV 相关的认知障碍（HAND）的神经心理学研究记录了广泛的功能领域的异常，尽管基本的病理生理学仍未解决。最常见的发现是精细运动控制缺陷和运动速度降低，但迄今为止，尚无神经影像学研究评估 HAND 中的基本运动控制。在这项研究中，我们使用脑磁图（MEG）评估了老年 HIV 感染者和匹配的未感染者对照组中运动规划的神经生理过程。MEG 是一种非侵入性的、直接测量神经活动的方法，具有良好的时空精度。在 MEG 记录期间，参与者注视中央十字线并使用优势手进行手指敲击任务。所有 MEG 数据均针对头部运动进行了校正，使用波束形成方法在时频域中进行了预处理和成像。所有分析均集中于运动前的β去同步化，已知其是运动规划的指标。我们的结果表明，HIV-1 感染者的左/右中央前回和辅助运动区的β去同步化相对于对照组不足。相比之下，HIV 感染者的右侧背外侧前额叶皮质和内侧前额叶区域的β反应异常强烈。此外，初级和辅助运动区的β活动幅度与 HIV 感染者的格罗夫钉板测试得分相关。这些结果表明，初级运动和感觉区域可能特别容易受到 HIV 相关的损伤，而前额叶皮质可能在维持感染患者的运动表现水平方面发挥代偿作用。
