Jiang Y, Chun M M
Department of Psychology, Yale University, USA.
J Exp Psychol Hum Percept Perform. 2001 Aug;27(4):895-918.
Object substitution masking occurs when a lateral mask persists beyond the duration of a target, reflecting reentrant processes in vision (V. Di Lollo, J. Enns, & R. Rensink, 2000). The authors studied whether substitution masking is location specific and whether it is symmetric around the target. A brief circular display of letters was presented along with a mask that designated the target. The mask was centered on the target or 1.1 degrees to the central or to the peripheral side. Substitution masking was found even when the target and the mask were at different locations. It was asymmetric and stronger when the mask was to the peripheral side of the target than to the central side. Asymmetric substitution was observed using various masks. It could not be explained by retina acuity gradients and was not attenuated by focused attention. The authors propose that target selection triggers an asymmetric inhibitory surround that is stronger toward the central side of the target.
当一个侧向掩蔽持续时间超过目标刺激的持续时间时，就会出现客体替代掩蔽，这反映了视觉中的折返过程（V. 迪洛洛、J. 恩斯和R. 任辛克，2000）。作者研究了替代掩蔽是否具有位置特异性，以及它是否围绕目标对称。呈现了一个简短的字母圆形显示以及一个指定目标的掩蔽。掩蔽以目标为中心，或者在中心或周边一侧偏离1.1度。即使目标和掩蔽位于不同位置，也发现了替代掩蔽。它是不对称的，当掩蔽位于目标的周边一侧时比位于中心一侧时更强。使用各种掩蔽都观察到了不对称替代。它无法用视网膜敏锐度梯度来解释，并且不会因集中注意力而减弱。作者提出，目标选择会触发一个不对称抑制性周边，该周边朝向目标的中心一侧更强。
