Crowding in central and eccentric vision: the effects of contour interaction and attention.

摘要: Purpose To quantify the crowding effect with eccentric stimuli and to determine relative contribution of neural interaction attention in central vision. Methods Monocular visual acuity was measured computer-generated tumbling E Landolt C targets presented centrally or at 2 degrees right field. Crowding distractors were designed cause increasing contour need for focused attention. A four-alternative forced-choice method constant used. In experiment distance between target varied. Results Data are terms normalized acuity. vision minimal, mainly caused by interaction, did not occur more than four stroke widths distant. far greater magnitude extent (occurring as 16 distant) attentional factors. Conclusions The results indicate that differs quantitatively qualitatively from effects consistent proposed size cortical processing zones. discussed reference current theories preattentive attentive tasks subjects low due scotoma who use an retinal locus fixation.