Multisensory stimuli improve relative localisation judgments compared to unisensory auditory or visual stimuli

Abstract

17Observers performed a relative localisation task in which they reported whether the second 18 of two sequentially presented signals occurred to the left or right of the first. Stimuli were 19 detectability--matched auditory, visual, or auditory--visual signals and the goal was to 20 compare changes in performance with eccentricity across modalities. Visual performance 21 was superior to auditory at the midline, but inferior in the periphery, while auditory--visual 22 performance exceeded both at all locations. No such advantage was seen when 23 performance for auditory--only trials was contrasted with trials in which the first stimulus 24 was auditory--visual and the second auditory only. 25 26 27 28

Auditory Space Perception in the Blind: Horizontal Sound Localization in Acoustically Simple and Complex Situations

“…We assume that the present results can be explained in terms of the lack of retinovisuomotor calibration of the auditory space with blindness and by the specificities of the multisensory mechanisms of spatial calibration that replace visual calibration in the blind (Lewald, 2002a, 2002b, 2013; Zwiers et al., 2001a, 2001b, 2003). In this context, it is important to note that in normal-sighted persons, visual localization acuity is maximal in the foveal region and decreases substantially with increasing eccentricity (Charbonneau et al., 2013; Freeman, Wood, & Bizley, 2018; Mateeff & Gourevich, 1983; Perrott, Costantino, & Cisneros, 1993). As mentioned earlier, auditory localization acuity also increases with increasing eccentricity (Blauert, 1997; Carlile et al., 2016; Charbonneau et al., 2013; Freeman et al., 2018; Makous & Middlebrooks, 1990; Mills, 1958; Röder et al., 1999; Wood & Bizley, 2015).…”

“…In this context, it is important to note that in normal-sighted persons, visual localization acuity is maximal in the foveal region and decreases substantially with increasing eccentricity (Charbonneau et al., 2013; Freeman, Wood, & Bizley, 2018; Mateeff & Gourevich, 1983; Perrott, Costantino, & Cisneros, 1993). As mentioned earlier, auditory localization acuity also increases with increasing eccentricity (Blauert, 1997; Carlile et al., 2016; Charbonneau et al., 2013; Freeman et al., 2018; Makous & Middlebrooks, 1990; Mills, 1958; Röder et al., 1999; Wood & Bizley, 2015). Furthermore, the cross-modal bias (i.e., the ability of a visual signal to influence the localization of an auditory target) and the ventriloquism effect (i.e., the visual capture of sounds with presentation of spatially incongruent bimodal targets) have been shown to be maximal at central locations and to decrease with eccentricity (Charbonneau et al., 2013; Hairston et al., 2003; Lewald & Guski, 2003).…”