以動態光點識別動作協調形態及性別

Coordination pattern and gender identification from a point light display

目的：以生態心理學理論中有關訊息恆定性及特殊性的概念，檢驗一、是否可由個體發生的生物動作識別性別。二、不同動作經驗者是否有不同的環境賦使。方法：以一台Sony數位攝影機（30Hz）以矢狀面拍攝在各關節點及頭部貼上反光點之體操專長學生10人實施後空翻、後手翻動作，拍攝後做影片對比處理，使影片僅呈現光點。體操教練、體育科系學生及一般大學生共52人為實驗參與者，觀看影片動作及識別動作者之性別。所得資料運用單因子變異數分析及t考驗等統計方法加以處理分析。結果：一、三組實驗參與者對影片動作都能正確識別。二、以性別辨識得分統計考驗結果發現，體操教練高於體育科系高於一般科系；另以辨識一致性進行考驗，結果亦與辨識得分類似。三、以起跳瞬間之軀幹仰角進行考驗，發現後手翻時男性角度較女性顯著為小，而後空翻時男女角度雖未達顯著，但女性仍有較小的趨勢。結論：以動態光點呈現之個體發生動作（ontogenetic movement），可提供足夠訊息，辨識特定協調型態，支持環境中訊息恆定性的主張；而不同專長運動經驗對辨別從事動作者性別能力的不同，則反應環境中訊息賦使的特性。環境中的各種恆定訊息有待需要者主動偵測，而知覺能力受個體經驗影響，特殊環境經驗為環境賦使能力不同之主要因素。

Purpose: Based on the concept of information constancy and specificity in the theory of ecological psychology, the present study examines whether: 1.There is invariant information in point light display to reveal the gender of the performers. 2.Coaches and athletes who had more specific training experiences in a particular discipline will show superior affordance than others. Methods: A 30Hz Sony digital camera was used to videotape the sagittal view of back flip and back handspring movements of 10 varsity gymnasts. Reflective markers were attached on the major joints and the temple of the gymnasts whiling videotaping, and post-processing the vide tape resulted in displaying only the point markers in playback. Fifty two participants including gymnastic coaches, college PE major students, and non-PE major students viewed the edited tapes and were asked to identify the nature of the point light display and the gender of the performers. Two statistic analyses, including independent sample one-way ANOVA and t-test were used. Results: 1.The results showed that all viewers could correctly identify the displayed movement. 2.Gymnastic coaches are significantly better at gender identification than the other 2 groups of viewers. 3.Post hoc kinematics analyses showed a significant gender difference for shoulder-hip angle in back handspring, but did not reach the significant level for back flip. Conclusion: The results of the study provide evidence to support the invariant property of information that the point light display of the ontogenetic movement offers sufficient information for identifying specific coordination patterns. The differential gender identification results demonstrate the affordance property of the viewer-information interaction. The invariant information is picked up by the perceiver, and the affordance is individual-specific and dependent on the specific experiences of the perceivers.