Kwan Heather, Scarapicchia Vanessa, Halliday Drew, MacDonald Stuart, Gawryluk Jodie R
Department of Psychology, University of Victoria, Victoria, British Columbia, Canada.
Institute on Aging and Lifelong Health, University of Victoria, British Columbia, Canada.
Aging Brain. 2022 Jan 19;2:100029. doi: 10.1016/j.nbas.2022.100029. eCollection 2022.
Healthy aging can include declines in processing speed and executive function. Further research is needed to characterize the neurobiological underpinnings of these cognitive changes in older adulthood. The current study used functional near infrared spectroscopy (fNIRS), an optical neuroimaging technique, to examine differences in cerebral oxygenation between healthy older adults (OA) and younger adults (YA) during a measure of cognitive interference.
Thirty-four participants were sampled from two age groups: YA (mean age = 28.1 years, SD = 2.8, F = 9) and OA (mean age = 70.9 years, SD = 5.4, F = 9). Participants completed the Multi-Source Interference Task (MSIT), a measure of executive function with high and low-demand conditions, while undergoing fNIRS recordings using a TechEn CW6 system with 34-source-detector channels, situated over the prefrontal cortex. Functional activation patterns, accuracy, and reaction time were compared between and within groups for each condition.
Behaviourally, during the control condition, OA and YA had comparable accuracy, although OA had significantly slower reaction times than YA. During the interference condition, OA had significantly lower accuracy and slower reaction times than YA. Results demonstrated a significant difference between groups with an age-related increase in HbO for OA in both conditions (p < 0.05). Within groups, OA showed greater activation during the control condition, while YA demonstrated greater activation during the interference condition.
The findings suggest that OA recruit additional neural resources to achieve similar behavioural performance during low-level cognitive interference, but that compensation in OA may be insufficient to support behavioural performance at higher levels of interference.
健康老龄化可能包括处理速度和执行功能的下降。需要进一步研究以明确成年后期这些认知变化的神经生物学基础。本研究使用功能性近红外光谱技术（fNIRS），一种光学神经成像技术，来检测健康老年人（OA）和年轻人（YA）在认知干扰测量过程中脑氧合的差异。
从两个年龄组中抽取34名参与者：年轻人（平均年龄 = 28.1岁，标准差 = 2.8，F = 9）和老年人（平均年龄 = 70.9岁，标准差 = 5.4，F = 9）。参与者完成多源干扰任务（MSIT），这是一项在高低需求条件下测量执行功能的任务，同时使用TechEn CW6系统在额叶前额皮质上方通过34个源探测器通道进行fNIRS记录。比较了每组在每种条件下组间和组内的功能激活模式、准确性和反应时间。
在行为上，在对照条件下，老年人和年轻人的准确性相当，尽管老年人的反应时间明显比年轻人慢。在干扰条件下，老年人的准确性明显低于年轻人，反应时间也更慢。结果表明，在两种条件下，与年龄相关的老年人HbO增加在组间存在显著差异（p < 0.05）。在组内，老年人在对照条件下表现出更大的激活，而年轻人在干扰条件下表现出更大的激活。
研究结果表明，老年人在低水平认知干扰期间会调用额外的神经资源以实现相似的行为表现，但老年人的补偿可能不足以支持更高水平干扰下的行为表现。
