目的：本研究的主要目的乃通過簡單聽覺反應時間測試手段，探討長短前期時間的操弄對於中晚期兒童訊息處理能力的影響，並比較前期時間長短影響注意力的年齡差異。方法：研究以8歲、10歲與12歲的兒童共192名為自願實驗參與者，並要求實驗參與者分別在前期時間平均6秒與30秒的情境下，在出現音源刺激時按壓觸動開關以測驗全部反應時間，Catsys 2000神經行為評估系統則用以產生刺激訊號的操控與反應時間的收集。結果：研究結果顯示在短前期情境10歲組兒童的反應時間顯著慢於12歲組，而長前期情境則10歲組與12歲組的反應時間未有統計的顯著差異，10歲組與12歲組兒童的反應時間變異性則未有年齡差異存在；8歲組兒童的反應時間與反應時間變異性也都顯著大於10歲組與12歲組兒童。結論：當前期時間過長時，12歲兒童的訊息處理能力也會退化至10歲兒童，說明了12歲兒童訊息處理能力仍處於不穩定的階段。

　　Purpose: The purpose of this study was to investigate the difference of information processing and the age through the manipulation of long or short foreperiod time in the approach of simple auditory reaction time test for middle/late children. Method: Eight-year-old, ten-year-old, and twelve-year-old children, 192 in total, were recruited as the voluntary participants in this study. Every participant was asked to press a switch to assess the response time after the stimulus of voice that following the warning signal around 6 second and 30 second. The Catsys 2000 system was used to generate the signal of stimulus and to acquire the information of reaction time. Results: The results showed the reaction time in ten-year-old children were slower than twelve-year-old children in the condition of short foreperiod, but not in the condition of long foreperiod. There were no statistical different between ten-year-old and twelve-year-old children for the variability of reaction time. The reaction time and variability of reaction time in eight-year-old children were the highest significantly. Conclusion: It indicated the ability of information processing for twelve-year-old children regress same as ten-year-old children under the condition of long foreperiod. The ability of information processing was an unstable stage in the age of twelve.