刺激時距與深度變化對於引發立體跳躍錯覺之影響

在較早期立體運動（cyclopean motion）研究結果認為屬長距（long-range）運動，但Patterson (1999)認為立體運動是有別於長距/短距（short-range）運動分類之第三條路徑。傳統上運動視覺的實驗均利用假象運動（apparent motion），但假象運動之知覺品質較難定量測量。Khuu、Kidd、Phu與Khambiye (2010)利用跳躍錯覺（saltation illusion）較有效地測量出立體運動視覺之品質。本研究引用其引發之時空條件操弄刺激時距（inter-stimulus interval, ISI）及深度變化等條件，探討引發立體跳躍錯覺之時空範圍。以此結果幫助探討立體運動視覺時間與空間特性，並討論立體運動視覺中像差類型間的歷程問題。實驗結果發現較易引發立體跳躍錯覺之時距範圍約150到450毫秒間，涵蓋了長短距運動之引發範圍；另外越大的深度變化越能引發較佳的立體跳躍錯覺。由實驗結果推論跳躍錯覺的引發範圍涵蓋長短距範圍支持立體運動歷程可能為兩者歷程之外的另一歷程，在本研究中也得到跨像差類型之刺激仍可協同引發立體跳躍錯覺，代表像差類型間可能非兩獨立的歷程。本研究同時亦發現刺激被背景遮蔽所導致的非形式補整（amodal completion）歷程可能影響某些情境下的跳躍錯覺知覺。此外，由於目前實驗中深度位置的判斷過程較粗糙使得結果在解釋上稍受限制，未來仍需更多研究探討及修正，以得到引發立體跳躍錯覺更精確的時間與空間範圍。

關鍵字

立體運動知覺；跳躍錯覺；假象運動

並列摘要

Cyclopean motion was belonged to long-range motion in previous study, but Patterson (1999) supposed that cyclopean motion is another pathway different from the long/short-range motion. In tradition, apparent motion is used to experiment of motion perception, but the quality of apparent motion is hard to measure. Applying saltation illusion, the quality of cyclopean motion is effective measured by Khuu, Kidd, Phu and Khambiye in 2010. In different conditions of inter-stimulus interval and depth variation, we investigated the range of time and space inducing the saltation illusion. By these results, we can discuss the property of time and space of cyclopean motion, and the process between the types of disparity. We found that cyclopean saltation is induced easily in the time range of 150~ 450 millisecond, covering the range of long/short-range motion. And larger the depth variation, lead to better cyclopean saltation. According to these results, we supported that cyclopean motion process is a different pathway from long/short-range process. Because of cyclopean saltation can be induced by the cross-type stimulus, we supposed the processes of disparity types are not self-independent. But we also found the amodal completion processing from the background flat occluding may influence the results. However, the explanation of this study is limited because of the measurement of depth position is not precise enough. To enhance the precise range of time and space, more study could be complied necessarily.