理學院: 心理學研究所指導教授: 葉素玲李魁安Li, Kuei-AnKuei-AnLi2017-03-022018-06-282017-03-022018-06-282016http://ntur.lib.ntu.edu.tw//handle/246246/272136快速地算出一群物件的平均大小是視覺系統的一項驚人的能力。然而,當在計算平均大小時,人們是否會過度仰賴來自左側視野的訊息(左側偏誤),目前仍不清楚。在此研究中,參與者會先看到一群球,隨後會出現一顆目標球。球群會平均地散布在螢幕的左右兩側,且在一半的嘗試中,相較於右側,左側的球平均大小較大(左大情境),另一半則相反(右大情境)。參與者須將目標球調整至與球群的平均大小相等。結果顯示出明顯的左側偏誤:相較於右大情境,參與者所報告的球群平均大小在左大情境中較大(實驗一)。若將注意力引導至右邊,則沒有左側偏誤 (實驗二)。此外,若左側球較右側球早出現,左側偏誤的強度會隨著左右側球出現的時間差增加而上升。反之,若右側球較早呈現,隨著時間差的上升,左側偏誤會逐漸減弱至消失,然後產生反向的偏誤(實驗三)。最後,我們紀錄參與者在觀看球群時的眼動反應,發現參與者會優先看向右邊且在右邊停留較久。我們推測此往右看的傾向為一種補償性策略,抵銷了在計算平均大小時的左側偏誤(實驗四)。總結來說,本研究發現當計算物件的平均大小時,參與者會過度仰賴左側視野的訊息,且此左側偏誤源自於往左側的注意力偏誤加速了對左側物件的處理。Rapidly estimating the mean size of a group of items of various sizes is one of the fascinating functions of our visual system. However, whether it yields left-side bias (LSB) where perceptual judgment tends to bias toward the information from the left visual field is still unclear. This issue was investigated by 4 experiments in this study. In each experiment, a set of disks were presented on the screen, followed by a central target disk. The mean size of the disks on one side (left or right) was larger than that on the other side, and which side contained disks with larger mean size was equally assigned among trials. Participants were asked to adjust the target disk to be the same as the mean size of the whole set (including both sides) of disks. Results showed a significant LSB: the size of the target disk was judged as larger when the left side contained disks of larger mean size, compared to when the situation was reversed (Experiment 1). The LSB vanished, when participants’ attention was cued to the right side by a color cue surrounding the right side before the presentation of the disks, implying that attention plays an important role on the LSB (Experiment 2). Furthermore, the magnitude of LSB increased with stimulus-onset asynchrony (SOA) when the disks on the left side were presented earlier. In contrast, the LSB first decreased and then reversed with SOA when the disks on the right side were presented earlier. This finding suggests that the LSB was enhanced by the prior entry effect on the attended side (Experiment 3). Finally, with free viewing, participants made more first saccade to the right side and had longer fixation duration there, presumably served as a compensatory role that eliminated the LSB on mean size estimation, which also supports the existence of the leftward attentional bias (Experiment 4). In summary, mean size estimation yields LSB which was induced by a leftward attentional bias that enhanced the prior entry effect on the left side.907698 bytesapplication/pdf論文公開時間: 2016/2/15論文使用權限: 同意有償授權(權利金給回饋學校)知覺平均大小左側偏誤注意力眼動perceptual averagesizeleft-side biasattentioneye movements平均大小知覺的左側偏誤:注意力在知覺平均中的角色Mean size estimation yields left-side bias: Role of attention on perceptual averagingthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/272136/1/ntu-105-R02227110-1.pdf