Visual search for apparent-length targets is modulated by the Müller-Lyer illusion

Busch, Astrid and Müller, Hermann J. (2004): Visual search for apparent-length targets is modulated by the Müller-Lyer illusion. In: Spatial Vision, Vol. 17, No. 4-5: pp. 417-441

Abstract

Is apparent object size represented in pre-attentive vision and can it influence visual search for size-defined targets in a spatially parallel manner? This question was investigated, using the Müller-Lyer illusion. Observers searched for a target line that was longer than the distractor lines. Test lines could be presented without context arrows (control); be adjoined by obtuse-angle context arrows (arrow heads pointing inward), making the lines appear longer; or by acute-angle arrows (heads pointing outward), making the lines appear shorter. These apparent-length modulations were larger for the target than for the distractor lines, thereby increasing and, respectively, decreasing the target–distractor length contrast. In line with these changes in contrast, target detection was found to be expedited by obtuse-angle arrows and impeded by acute-angle arrows, independently of the number of elements in the display. This finding provides further evidence for the pre-attentive processing of apparent object size.

• Item Type: Journal article
• Form of publication: Publisher's Version
• Faculties: Psychology and Education Science > Department Psychology > General and Experimental Psychology
• Subjects: 100 Philosophy and Psychology > 150 Psychology
• ISSN: 0169-1015
• Alliance/National Licence: This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
• Language: English