Effects of Acute Exercise and Age on Inhibitory Control: A Combined ERP and Source Localization Study

Abstract

本研究之目的為二： (一) 檢驗年齡是否影響急性運動對抑制控制的行為與電生理表現之效益；及 (二) 了解運動促進抑制控制表現的神經基質，並檢驗年齡是否影響該神經基質。本研究招募24位年輕男性 (平均年齡 = 24.0 ± 3.1 年) 及20位老年男性 (平均年齡 = 70.0 ± 3.3 年)。參與者以對抗平衡次序方式從事一次急性運動情境 (強度為 50-70%的心跳保留值) 與一次影片情境，其後使用Stroop叫色測驗進行抑制控制表現測量，同時進行認知行為與事件關聯電位的資料收集。行為表現的參數包含反應時間、反應正確率；事件關聯電位的參數則包含P3與N450成分波，另以sLORETA作為腦波源分析之工具。本研究結果顯示，急性運動能縮短參與者的反應時間，其效益不受認知作業的難度或參與者年齡所影響；作業難度對於反應時間產生的干擾於運動後有所減少，其效益不受年齡所影響。事件關聯電位部分，急性運動誘發較大的P3振幅並降低N450的振幅，其效益不受作業難度或年齡所影響。源分析部分，急性運動誘發年輕人大腦左側外側前額葉及前扣帶迴的活化；老年人則是於運動後於右半腦外側前額葉產生活化，伴隨前扣帶迴活化的降低。根據上述結果，本研究建議年輕人與老年人於急性運動後可能獲得相似的提升效益，惟其潛在的神經基質則因年齡有所不同。

The purposes of the current study were two-fold: (a) to examine whether age affects the acute exercise-elicited effect on behavioral and neuroelectric correlates of Stroop performance; and (b) to explore the neural substrates underlie the acute exercise-elicited effect, and how these substrates were affected by age. Twenty-four young males (Meanage = 24.0 ± 3.1 years) and 20 old males (Meanage = 70.0 ± 3.3 years) were recruited. Participants underwent a single bout of aerobic exercise (intensity at 50-70% of HRreserve) or a video condition in counter-balanced order. Afterwards, participants were administered with a Stroop color-word test, with concurrent collection of behavioral and event-related potential (ERP) data. Reaction times (RT), response accuracy, and Stroop interference (SI) in RT and accuracy were recorded and calculated as behavioral indices; the P3 and N450 component from ERP were selected as neuroelectric correlates. Additionally, a standardized low-resolution brain electromagnetic tomography (sLOREATA) was utilized as source localization analysis. The results revealed that acute exercise resulted in shorter RT regardless of congruency and age. A smaller SI in RT was also observed following exercise. Regarding ERPs, acute exercise resulted in larger P3 amplitude and smaller N450 amplitude regardless of congruency and age. With respect to source localization, acute exercise exclusively activated the lateral prefrontal cortex (PFC) and anterior cingulate cortex (ACC) in left hemisphere in young adults whereas acute exercise activated the lateral PFC in right hemisphere and deactivated the ACC in old adults. Taken together, the currentfindings suggest that while acute exercise facilitates inhibitory control in young and old adults in a similar manner, the neural substrates underlying the relationship are different.