Vision Science Graduate Group, University of California Berkeley, Berkeley, CA, USA.
Herbert Wertheim School of Optometry & Vision Science, University of California Berkeley, Berkeley, CA, USA.
J Vis. 2023 Mar 1;23(3):2. doi: 10.1167/jov.23.3.2.
Visual spatial attention can be allocated in two distinct ways: one that is voluntarily directed to behaviorally relevant locations in the world, and one that is involuntarily captured by salient external stimuli. Precueing spatial attention has been shown to improve perceptual performance on a number of visual tasks. However, the effects of spatial attention on visual crowding, defined as the reduction in the ability to identify target objects in clutter, are far less clear. In this study, we used an anticueing paradigm to separately measure the effects of involuntary and voluntary spatial attention on a crowding task. Each trial began with a brief peripheral cue that predicted that the crowded target would appear on the opposite side of the screen 80% of the time and on the same side of the screen 20% of the time. Subjects performed an orientation discrimination task on a target Gabor patch that was flanked by other similar Gabor patches with independent random orientations. For trials with a short stimulus onset asynchrony between cue and target, involuntary capture of attention led to faster response times and smaller critical spacing when the target appeared on the cue side. For trials with a long stimulus onset asynchrony, voluntary allocation of attention led to faster reaction times but no significant effect on critical spacing when the target appeared on the opposite side to the cue. We additionally found that the magnitudes of these cueing effects of involuntary and voluntary attention were not strongly correlated across subjects for either reaction time or critical spacing.
一种是主动将注意力分配到与行为相关的世界位置，另一种是被动地被显著的外部刺激吸引。预提示空间注意已被证明可以提高许多视觉任务的感知表现。然而，空间注意对视觉拥挤的影响，即识别杂乱中目标物体的能力下降，远不那么清楚。在这项研究中，我们使用反提示范式分别测量了非自愿和自愿空间注意对拥挤任务的影响。每次试验开始时，都会出现一个短暂的外围提示，该提示预测在 80%的时间里，拥挤的目标会出现在屏幕的另一侧，而在 20%的时间里，目标会出现在屏幕的同一侧。受试者在一个目标 Gabor 补丁上执行方向辨别任务，该目标 Gabor 补丁被其他具有独立随机方向的类似 Gabor 补丁包围。对于具有短刺激起始时间间隔的试验，在提示和目标之间，注意力的非自愿捕获导致当目标出现在提示侧时，反应时间更快，关键间隔更小。对于具有长刺激起始时间间隔的试验，当目标出现在提示的相反侧时，自愿分配注意力导致反应时间更快，但对关键间隔没有显著影响。我们还发现，对于反应时间或关键间隔，这些非自愿和自愿注意力的提示效应的大小在不同受试者之间没有很强的相关性。
