Aging suppresses subthalamic neuronal activity in patients with Parkinson’s disease

Age is a primary risk factor for Parkinson’s Disease (PD) however the effects of ageing in the Parkinsonian brain remain poorly understood, particularly for deep brain structures. We investigated intraoperative micro-electrode recordings from the subthalamic nucleus (STN) of PD patients aged between 42 and 76 years. Age was associated with decreased oscillatory beta power and non-oscillatory high-frequency power, independent of PD-related variables. Single unit firing and burst rates were also reduced, whereas coefficient of variation and the structure of burst activity were unchanged. Phase synchronization (debiased phase lag index) between sites was pronounced in the beta band between electrodes in the superficial STN, but was unaffected by age. Our results show that aging was associated with reduced neuronal activity, without changes to its temporal structure. We speculate that the loss of activity in the STN may mediate the relationship between PD and age.

年龄是帕金森病（Parkinson’s Disease, PD）的主要风险因素，但衰老对帕金森病患者大脑的影响仍知之甚少，尤其是针对深部脑结构。我们研究了42至76岁PD患者丘脑底核（subthalamic nucleus, STN）的术中微电极记录。年龄与振荡β功率及非振荡高频功率降低相关，且不受PD相关变量的干扰。单单位放电频率与爆发频率同样降低，而变异系数及爆发活动的结构未发生改变。位点间的相位同步（去偏相位滞后指数，debiased phase lag index）在丘脑底核浅层电极间的β波段尤为显著，但不受年龄影响。我们的结果表明，衰老与神经元活动减少相关，但其时间结构未发生改变。我们推测，丘脑底核活动的丧失可能介导了PD与年龄之间的关联。