Investigating effects of aging on neurophysiological mechanisms underlying working memory provides a better understanding of potential targets for brain intervention to prevent cognitive decline. Theta-gamma coupling (TGC) indexes the ability to order information processed during working memory tasks. Frontal theta event-related synchronization (ERS) and parietal alpha event-related desynchronization (ERD) index cognitive control and interference inhibition, respectively. Relative contributions of TGC, theta ERS, and alpha ERD in relation to stimulus presentation are not characterized. Further, differential effect of normal aging on pre- or post-stimulus processes is unknown. Electroencephalography was recorded in 66 younger and 41 older healthy participants while performing 3-back working memory task. We assessed relationships between 3-back task performance and each of post-stimulus TGC, pre-stimulus parietal alpha ERD, and pre-stimulus frontal theta ERS in each age group. While older adults performed worse on 3-back task than younger adults, TGC, alpha ERD, or theta ERS did not differ between the two groups. TGC was positively associated with 3-back performance in both age groups; pre-stimulus alpha ERD was associated with performance among younger adults; and pre-stimulus theta ERS was not associated with performance in either group. Our findings suggest that both pre-stimulus interference inhibition and post-stimulus ordering of information are important for working memory in younger adults. In contrast, performance in older adults appears to depend only on post-stimulus ordering of information. These specific contributions of neurophysiological resources may explain the poorer performance of older adults and suggest different targets to enhance working memory in age groups.

研究衰老对工作记忆背后的神经生理机制的影响可以更好地理解大脑干预的潜在目标，以防止认知能力下降。 Theta-gamma 耦合 (TGC) 索引了在工作记忆任务期间对处理的信息进行排序的能力。额叶θ事件相关同步（ERS）和顶叶α事件相关去同步（ERD）分别指数认知控制和干扰抑制。 TGC、theta ERS ​​和 alpha ERD 对刺激呈现的相对贡献尚未表征。此外，正常衰老对刺激前或刺激后过程的不同影响尚不清楚。 66 名年轻健康参与者和 41 名老年健康参与者在执行 3-back 工作记忆任务时记录了脑电图。我们评估了每个年龄组中三背任务表现与刺激后 TGC、刺激前顶叶 α ERD 和刺激前额叶 ERS ​​之间的关系。虽然老年人在 3 背任务上的表现比年轻人差，但两组之间的 TGC、α ERD 或 theta ERS ​​没有差异。在两个年龄组中，TGC 与三后卫表现呈正相关；刺激前 α ERD 与年轻人的表现相关；刺激前 theta ERS ​​与两组的表现均无关。我们的研究结果表明，刺激前干扰抑制和刺激后信息排序对于年轻人的工作记忆都很重要。相比之下，老年人的表现似乎仅取决于刺激后的信息排序。 神经生理学资源的这些具体贡献可能解释了老年人表现较差的原因，并提出了增强各年龄段工作记忆的不同目标。