City Research Online

A visual search asymmetry for novelty in the visual field based on sensory adaptation

Morgan, M. J. and Solomon, J. A. ORCID: 0000-0001-9976-4788 (2019). A visual search asymmetry for novelty in the visual field based on sensory adaptation. Attention, Perception and Psychophysics,


The ability to detect sudden changes in the environment is important for survival. However, studies of “change blindness” have shown that image differences are hard to detect when a time delay or a mask is imposed between the different images. However, when sensory adaptation is permitted by accuratefixation, we find that change detection is not only possible but asymmetrical: a single changed target amongst 15 unchanging distractors is much easier to detect than a target defined by its lack of change. Although adaptation may selectively reduce the apparent contrast of unchanged objects, the asymmetry in “change salience” cannot be attributed to any such reduction because genuine reductions in target contrast increase, rather than decrease, target detectability. Analogous results preclude attribution to apparent differences between a) target onset and distractor onset and b) their temporal frequencies (both flickered at 7.5 Hz, minimizing afterimages). Our results demonstrate a hitherto underappreciated (or unappreciated) advantage conferred by low-level sensory adaptation: it automatically elevates the salience of previously absent objects.

Publication Type: Article
Additional Information: This is a post-peer-review, pre-copyedit version of an article accepted for publication in published in Attention, Perception and Psychophysics. The final authenticated version is to be available online at:
Departments: School of Health Sciences > Optometry & Visual Science
[img] Text - Accepted Version
This document is not freely accessible due to copyright restrictions.

To request a copy, please use the button below.

Request a copy



Downloads per month over past year

View more statistics

Actions (login required)

Admin Login Admin Login