Huckauf Anke, Heller Dieter
Faculty of Media, Bauhaus-University of Weimar, Weimar, Germany.
Percept Psychophys. 2004 May;66(4):584-95. doi: 10.3758/bf03194903.
To study the question of which processes contribute to crowding and whether these are comparable to those of visual temporal masking, we varied the stimulus onset asynchrony (SOA) between target and flankers in a crowding setting. Monotonically increasing Type A masking functions observedfor small spacings and large eccentricities indicate that the integration of information from target and flankers underlies crowding. Decreasing masking functions obtained for large spacings and small eccentricities relate processes of crowding to those contributing to Type B masking. In addition, Type B masking was more frequent with letter-like nonletter flankers than with letter flankers, suggesting that Type B masking, just like crowding over large areas, is due to higher level interactions. The rapid decrease of the effects of interletter spacing and eccentricity with increasing SOA indicates that positional information is transient.
为了研究哪些过程导致拥挤以及这些过程是否与视觉时间掩蔽的过程相似，我们在拥挤情境中改变了目标刺激和侧翼刺激之间的刺激起始异步性（SOA）。在小间距和大离心率条件下观察到单调递增的A型掩蔽函数，这表明目标刺激和侧翼刺激信息的整合是拥挤现象的基础。在大间距和小离心率条件下获得的递减掩蔽函数将拥挤过程与导致B型掩蔽的过程联系起来。此外，与字母侧翼刺激相比，类似字母的非字母侧翼刺激更常出现B型掩蔽，这表明B型掩蔽与大面积的拥挤现象一样，是由更高层次的相互作用引起的。随着SOA增加，字母间距和离心率效应的迅速降低表明位置信息是短暂的。
