Department of Neurology, Zealand University Hospital, Roskilde, Denmark.
Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
J Alzheimers Dis. 2020;75(4):1181-1190. doi: 10.3233/JAD-200083.
Studies on mice models of Alzheimer's disease (AD) have suggested potential therapeutic benefits of intermittent photic stimulation at 40 Hz.
We examined the physiological response of 40 Hz intermittent photic stimulation (IPS) on routine EEG in a large retrospective cohort to investigate the effects of age on induced gamma oscillations by intermittent photic stimulation. Since most AD patients are elderly, it is important for future research to know if age affects photic stimulation.
Retrospective data from 1,464 subjects aged 0- 91. We performed frequency analysis and automatic peak detection and used regression analysis to investigate the effects of age and sex on peak frequencies and amplitude changes. To investigate the spread of the induced gamma oscillations, we assessed averaged topographies of 40 Hz band power.
There was a statistically significant but very minor effect of age on amplitude change (- 0.002 normalized power per year, p < 0.0001) but not for sex (p = 0.728). Detection probability of induced peaks was significantly predicted by both age (OR = 0.988, CI 95 % [0.984, 0.993], p < 0.00001) and sex (OR = 0.625, CI 95 % [0.496, 0.787>], p < 0.0001). The induced 40 Hz gamma entrainment is spatially confined to the occipital area.
There is a significant effect of age on induced gamma activity, but advanced age does not fundamentally change the behavior of the response in either magnitude or spatial distribution. This fact is important regarding future research into the possible therapeutic effects of photic stimulation in patients with AD.
对阿尔茨海默病（AD）小鼠模型的研究表明，40Hz 间频光刺激具有潜在的治疗益处。
我们通过大样本回顾性队列研究，在常规脑电图上检测 40Hz 间频光刺激（IPS）的生理反应，以研究年龄对间歇光刺激诱导的伽马振荡的影响。由于大多数 AD 患者为老年人，因此了解年龄是否影响光刺激对未来的研究非常重要。
回顾性分析 1464 名年龄在 0 至 91 岁的受试者的数据。我们进行了频率分析和自动峰值检测，并使用回归分析研究年龄和性别对峰值频率和幅度变化的影响。为了研究诱导的伽马振荡的传播，我们评估了 40Hz 频段功率的平均地形图。
年龄对振幅变化有统计学意义但非常小的影响（每年 0.002 归一化功率，p<0.0001），但性别无影响（p=0.728）。诱导峰的检测概率显著受年龄（OR=0.988，95%CI[0.984，0.993]，p<0.00001）和性别（OR=0.625，95%CI[0.496，0.787]，p<0.0001）的影响。诱导的 40Hz 伽马同步主要局限于枕叶区域。
年龄对诱导的伽马活动有显著影响，但年龄增长并不会从根本上改变反应的幅度或空间分布。这一事实对于未来研究光刺激对 AD 患者的可能治疗效果非常重要。
