| 摘要: | 時間準備 (Temporal preparation) 是指個體預期即將發生事件之時間點的認知過程，藉此促進更有效率的動作反應。前時距效應 (Foreperiod effect) 為此一項經典的現象，當警告訊號與目標刺激之間的間隔越長，反應時間則縮短，歸因於反應準備的提升，而對於時間預期的改善。其中，時間準備在如競技運動等動態情境中扮演關鍵角色，運動員在知覺、預期及動作表現等層面普遍優於非運動員，而這些優勢被認為源自於長期運動訓練所帶來的神經認知適應。先前研究顯示，從事開放性技術運動 (如網球) 的運動員，對時間線索更為敏銳，且在時間不確定情境下表現更佳。
儘管時間準備對運動表現的重要性已被廣泛認可，既有文獻多採用傳統認知作業與靜態反應指標 (如按鍵反應)，較難捕捉真實世界中動作控制的複雜性。另一方面，關於時間準備與精細動作表現之間的神經機制亦尚未充分探討。有鑑於此，本研究結合精確的動作控制評估、認知作業與腦電圖(EEG)，以探討時間準備在精細動作中的行為與神經對應。
本研究包含兩個實驗。實驗一探討不同前備期間隔 (410毫秒、740毫秒與 940 毫秒) 如何影響動作控制與準備期的腦部活動。參與者執行一個簡單反應時間作業，同時透過 Pinch/Grip Analyzer (MIE Medical Research, UK) 連續測量握力表現，並同步記錄 EEG 資料。相較於傳統反應方式，握力數據提供了更敏感的動作表現指標。行為結果顯示，較長的前時距呈現更快的反應時間、更高的加速力道，以及更有效率地達到目標力量，顯示延長的準備時間可增進神經肌肉的預備狀態。事件相關電位模式 (Event-Related Mode Analysis, ERM) 分析的結果，則顯示大腦皮質在時間準備中的不同貢獻：頂葉的P3成分與評估歷程相關，於時間壓力下可能干擾動作精準性；前輔助運動區 (pre-SMA) 的N1成分反映內在時間敏感性；右側額下回 (rIFG) 的N2成分則同時支持更快且更精確的反應，顯示其在整合高階控制、預期調節與感覺-動作處理中扮演關鍵角色。
在實驗一的基礎上，實驗二進一步探討有無運動訓練背景者在時間準備上的差異。研究設計一項模擬真實運動情境的新穎作業，以評估時間不確定條件下的精細動作控制。結果顯示，儘管隨著任務難度提高，運動員與非運動員的反應時間皆延長，運動員在握力控制的穩定性與精準度方面顯著優於非運動員，顯示運動訓練可能提升時間知覺並強化在不可預期情境下的動作控制能力。本研究顯示，延長的時間準備可顯著提升精細動作表現，透過促進神經肌肉的準備狀態與更有效的認知控制機制。運動經驗則進一步強化這種效應，使個體在面對時間不確定的情境下，能展現更穩定與精準的動作表現，整體而言，有助於了解運動過程中，認知預期、動作控制與大腦神經動態歷程之間的關係。
;Temporal preparation refers to the cognitive process by which individuals anticipate the timing of an upcoming event, facilitating more efficient motor responses. A well-established phenomenon illustrating this is the foreperiod effect—reaction times tend to decrease as the interval between a warning signal and target stimulus lengthens. This enhancement in response readiness is attributed to improved temporal expectancy. Temporal preparation plays a pivotal role in dynamic contexts such as competitive sports, where athletes consistently outperform non-athletes in perceptual, anticipatory, and motor domains. These advantages are believed to stem from neurocognitive adaptations acquired through extensive sports training. Prior research has shown that athletes engaged in open-skill sports—such as tennis—demonstrate heightened sensitivity to temporal cues and are better equipped to perform under conditions of temporal uncertainty.
Despite the recognized importance of temporal preparation in athletic performance, much of the existing literature has relied on traditional cognitive paradigms involving static response measures (e.g., keypress), which may fail to capture the complexities of real-world motor control. Moreover, the neural mechanisms linking temporal preparation with fine motor performance remain underexplored. To address these limitations, the present research integrated precise motor control assessments with cognitive tasks and electroencephalography (EEG) to investigate the behavioral and neural correlates of temporal preparation in fine motor tasks.
The study comprised two experiments. Experiment 1 examined how variable foreperiod intervals (410 ms, 740 ms, and 940 ms) influence motor control and preparatory brain activity. Participants performed a simple reaction time task while grip force was continuously measured using the Pinch/Grip Analyzer (MIE Medical Research, UK), and EEG data were simultaneously recorded. Compared to conventional response modalities, grip force data provided a more sensitive measure of motor performance. Behavioral results indicated that longer foreperiods led to faster reaction times, greater force acceleration, and more efficient attainment of the target force. These findings suggest that extended preparation enhances neuromuscular readiness. EEG results from the ERM analysis revealed distinct cortical contributions to temporal preparation. The parietal P3 component was associated with evaluative processes that, under time pressure, may interfere with motor precision. The N1 component in the pre-SMA reflected internal timing sensitivity, while the N2 component in the rIFG supported both faster and more accurate responses, suggesting its critical role in integrating top-down control, anticipatory modulation, and sensorimotor processing during time-sensitive actions.
Building upon these findings, Experiment 2 investigated whether temporal preparation differs between individuals with and without sports training. A novel task simulating real-world sports scenarios was developed to assess fine motor control under temporal uncertainty. Results revealed that although both athletes and non-athletes showed longer response times as task complexity increased, athletes exhibited significantly greater stability and precision in grip force control. This suggests that athletic training may refine temporal perception and enhance motor control in unpredictable environments.
In summary, this research demonstrates that temporal preparation significantly improves fine motor performance, particularly when preparation time is extended. Furthermore, athletic experience appears to modulate these effects, allowing for more precise motor execution under uncertainty. These findings offer new insights into the interplay between cognitive anticipation, motor execution, and neural dynamics, with implications for performance optimization and training in both athletic and clinical populations. |
