Auditory enhancement of visual perception at threshold depends on visual abilities

• Published in: Brain research Vol. 1396; pp. 35 - 44
• Main Authors: Caclin, Anne, Bouchet, Patrick, Djoulah, Farida, Pirat, Elodie, Pernier, Jacques, Giard, Marie-Hélène
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 17.06.2011; Elsevier
• Subjects: Acoustic Stimulation - methods; Adolescent; Adult; Audiovisual interactions; Auditory Perception - physiology; Biological and medical sciences; brain; Collinear facilitation; Cues; detection limit; Detection threshold; Ear and associated structures. Auditory pathways and centers. Hearing. Vocal organ. Phonation. Sound production. Echolocation; Eye and associated structures. Visual pathways and centers. Vision; Female; Fundamental and applied biological sciences. Psychology; Humans; Inter-individual variability; Male; Neurology; Photic Stimulation - methods; Sensory Thresholds - physiology; Vertebrates: nervous system and sense organs; vision; Visual Perception - physiology; Young Adult; Audiovisual interactions; Collinear facilitation; Inter-individual variability; Detection threshold; Facilitation; Threshold detection; Perception threshold; Variability; Psychophysics; Visual perception; Audiovisual; Hearing; Vision
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/j.brainres.2011.04.016

Abstract Whether or not multisensory interactions can improve detection thresholds, and thus widen the range of perceptible events is a long-standing debate. Here we revisit this question, by testing the influence of auditory stimuli on visual detection threshold, in subjects exhibiting a wide range of visual-only performance. Above the perceptual threshold, crossmodal interactions have indeed been reported to depend on the subject's performance when the modalities are presented in isolation. We thus tested normal-seeing subjects and short-sighted subjects wearing their usual glasses. We used a paradigm limiting potential shortcomings of previous studies: we chose a criterion-free threshold measurement procedure and precluded exogenous cueing effects by systematically presenting a visual cue whenever a visual target (a faint Gabor patch) might occur. Using this carefully controlled procedure, we found that concurrent sounds only improved visual detection thresholds in the sub-group of subjects exhibiting the poorest performance in the visual-only conditions. In these subjects, for oblique orientations of the visual stimuli (but not for vertical or horizontal targets), the auditory improvement was still present when visual detection was already helped with flanking visual stimuli generating a collinear facilitation effect. These findings highlight that crossmodal interactions are most efficient to improve perceptual performance when an isolated modality is deficient.