Department of Special Education, University of Haifa, Haifa, Israel.
Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
J Vis. 2022 Aug 1;22(9):3. doi: 10.1167/jov.22.9.3.
Crowding refers to the failure to identify a peripheral object due to its proximity to other objects (flankers). This phenomenon can lead to reading and object recognition impairments and is associated with macular degeneration, amblyopia, and dyslexia. Crucially, the maximal target-flanker spacing required for the crowding interference (critical spacing) increases with eccentricity. This spacing is also larger when target and flankers appear along the horizontal meridian (radial arrangement) than when the flankers appear above and below the target (tangential arrangement). This phenomenon is known as radial-tangential anisotropy. Previous studies have demonstrated that transient attention can reduce crowding interference; however, it is still unclear whether and how attention interacts with radial-tangential anisotropy. To address this issue, we manipulated transient attention by using a cue at either the target (valid) or the fixation (neutral) location, in both radial and tangential target-flanker arrangements. Results showed that critical spacing was larger in the radial than in the tangential arrangement and that cueing the target location improved performance and reduced the critical spacing for both radial and tangential arrangements to the same extent. Together, our findings suggest that transient spatial attention plays an essential role in crowding but not in radial-tangential anisotropy.
拥挤是指由于周边物体（侧翼）的接近而无法识别一个外周物体的现象。这种现象可能导致阅读和物体识别障碍，与黄斑变性、弱视和阅读障碍有关。至关重要的是，拥挤干扰所需的最大目标-侧翼间距（临界间距）随离轴度增加而增加。当目标和侧翼出现在水平子午线（放射状排列）上时，与侧翼出现在目标上方和下方（切线排列）时相比，该间距更大。这种现象被称为放射状-切线各向异性。先前的研究表明，瞬态注意力可以减少拥挤干扰；然而，注意力是否以及如何与放射状-切线各向异性相互作用仍然不清楚。为了解决这个问题，我们通过在目标（有效）或注视（中性）位置使用提示，在放射状和切线目标-侧翼排列中操纵瞬态注意力。结果表明，在放射状排列中，临界间距大于切线排列，并且提示目标位置可以改善性能，并将两种排列的临界间距缩小到相同的程度。总之，我们的研究结果表明，瞬态空间注意力在拥挤中起着至关重要的作用，但在放射状-切线各向异性中不起作用。
