Abstract
In natural audio-visual environments, a change in depth is usually correlated with a change in loudness. In the present study, we investigated whether correlating changes in disparity and loudness would provide a functional advantage in binding disparity and sound amplitude in a visual search paradigm. To test this hypothesis, we used a method similar to that used by van der Burg et al. to show that non-spatial transient (square-wave) modulations of loudness can drastically improve spatial visual search for a correlated luminance modulation. We used dynamic random-dot stereogram displays to produce pure disparity modulations. Target and distractors were small disparity-defined squares (either 6 or 10 in total). Each square moved back and forth in depth in front of the background plane at different phases. The target’s depth modulation was synchronized with an amplitude-modulated auditory tone. Visual and auditory modulations were always congruent (both sine-wave or square-wave). In a speeded search task, five observers were asked to identify the target as quickly as possible. Results show a significant improvement in visual search times in the square-wave condition compared to the sine condition, suggesting that transient auditory information can efficiently drive visual search in the disparity domain. In a second experiment, participants performed the same task in the absence of sound and showed a clear set-size effect in both modulation conditions. In a third experiment, we correlated the sound with a distractor instead of the target. This produced longer search times, indicating that the correlation is not easily ignored.
Highlights
For the last fifty years [1], visual search paradigms have proven to be a useful tool to study feature integration [2] and allocation of attention [3]
An early study by Nakayama & Silverman [4] showed that distinguishing targets and distractors by their horizontal binocular disparity was sufficient to support efficient visual search
Harris, McKee & Watamaniuk [5] found that when binocular disparity was defined by spatiotemporal correlations, search performance became far less efficient
Summary
For the last fifty years [1], visual search paradigms have proven to be a useful tool to study feature integration [2] and allocation of attention [3]. A majority of studies using this paradigm have focused on the processing of basic feature dimensions such as luminance, color, orientation or motion, and have shown that searching for a target which is distinguished from the surrounding distractors by having, for example, a different orientation (or color, or luminance, etc) produces fast, efficient searches. An early study by Nakayama & Silverman [4] showed that distinguishing targets and distractors by their horizontal binocular disparity (stereopsis) was sufficient to support efficient visual search. This is an intriguing result because even though static stereopsis and stereomotion are each capable of supporting vivid and clearly discriminable perceptual structure, stereomotion seems to require serial search
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
