Visual motion disambiguation by a subliminal sound (original) (raw)
Related papers
Experimental Brain Research, 2004
When looking at two identical objects moving toward each other on a two-dimensional visual display, two different events can be perceived: the objects can either be seen to bounce off each other, or else to stream through one another. Previous research has shown that the large bias normally seen toward the streaming percept can be modulated by the presentation of an auditory event at the moment of coincidence. However, previous behavioral research on this crossmodal effect has always relied on subjective report. In the present experiment, we used a novel experimental design to provide a more objective/ implicit measure of the effect of an auditory cue on visual motion perception. In our study, two disks moved toward each other, with the point of coincidence hidden behind an occluder. When emerging from behind the occluder, the disks (one red, the other blue) could either follow the same trajectory (streaming) or else move in the opposite direction (bouncing). Participants made speeded discrimination responses regarding the side from which one of the disks emerged from behind the occluder. Participants responded more rapidly on streaming trials when no sound was presented and on bouncing trials when the sound was presented at the moment of coincidence. These results provide the first empirical demonstration of the auditory modulation of an ambiguous visual motion display using an implicit/objective behavioral measure of perception.
Visual illusion induced by sound
2002
We present the first cross-modal modification of visual perception which involves a phenomenological change in the quality-as opposed to a small, gradual, or quantitative change-of the percept of a non-ambiguous visual stimulus. We report a visual illusion which is induced by sound: when a single flash of light is accompanied by multiple auditory beeps, the single flash is perceived as multiple flashes. We present two experiments as well as several observations which establish that this alteration of the visual percept is due to cross-modal perceptual interactions as opposed to cognitive, attentional, or other origins. The results of the second experiment also reveal that the temporal window of these audiovisual interactions is approximately 100 ms.
Alternation of Sound Location Induces Visual Motion Perception of a Static Object
PLoS ONE, 2009
Background: Audition provides important cues with regard to stimulus motion although vision may provide the most salient information. It has been reported that a sound of fixed intensity tends to be judged as decreasing in intensity after adaptation to looming visual stimuli or as increasing in intensity after adaptation to receding visual stimuli. This audiovisual interaction in motion aftereffects indicates that there are multimodal contributions to motion perception at early levels of sensory processing. However, there has been no report that sounds can induce the perception of visual motion.
Sound-contingent visual motion aftereffect
BMC Neuroscience, 2011
Background: After a prolonged exposure to a paired presentation of different types of signals (e.g., color and motion), one of the signals (color) becomes a driver for the other signal (motion). This phenomenon, which is known as contingent motion aftereffect, indicates that the brain can establish new neural representations even in the adult's brain. However, contingent motion aftereffect has been reported only in visual or auditory domain. Here, we demonstrate that a visual motion aftereffect can be contingent on a specific sound. Results: Dynamic random dots moving in an alternating right or left direction were presented to the participants. Each direction of motion was accompanied by an auditory tone of a unique and specific frequency. After a 3-minutes exposure, the tones began to exert marked influence on the visual motion perception, and the percentage of dots required to trigger motion perception systematically changed depending on the tones. Furthermore, this effect lasted for at least 2 days. Conclusions: These results indicate that a new neural representation can be rapidly established between auditory and visual modalities.
A single auditory tone alters the perception of multiple visual events
Journal of vision, 2014
We aimed to show that a single auditory tone crossmodally affects multiple visual events using a multiple stream/bounce display (SBD), consisting of two disk pairs moving toward each other at equal speeds, coinciding, and then moving apart in a two-dimensional (2-D) display. The temporal offsets were manipulated between the coincidences of the disk pairs (0 to ±240 ms) by staggering motion onset between the pairs. A tone was presented at the coincidence timing of one of the disk pairs on half of the trials. Participants judged whether the disks in each of two pairs appeared to stream through or bounce off each other. Results show that a tone presented at either of the disk pairs' coincidence points promoted bouncing percepts in both disk pairs compared to no-tone trials. Perceived bouncing persisted in the disk-pair whose coincidence was offset 60 ms before and up to more than 120 ms after the audiovisual coincidence timing of the other disk-pair. The temporal window of bounce p...
Journal of Vision, 2012
With few exceptions, the sound-induced bias toward bouncing characteristic of the stream/bounce effect has been demonstrated via subjective responses, leaving open the question whether perceptual factors, decisional factors, or some combination of the two underlie the illusion. We addressed this issue directly, using a novel stimulus and signal detection theory to independently characterize observers' sensitivity (d 0 ) and criterion (c) when discriminating between objective streaming and bouncing events in the presence or absence of a brief sound at the point of coincidence. We first confirmed that sound-induced motion reversals persist despite rendering the targets visually distinguishable by differences in texture density. Sound-induced bouncing persisted for targets differing by as many as nine just-noticeable-differences (JNDs). We then exploited this finding in our signal detection paradigm in which observers discriminated between objective streaming and bouncing events. We failed to find any difference in sensitivity (d 0 ) between sound and no-sound conditions, but we did observe a significantly more liberal criterion (c) in the sound condition than the no-sound condition. The results suggest that the auditory-induced bias toward bouncing in this context is attributable to a sound-induced shift in criterion implicating decisional processes rather than perceptual processes determining responses to these displays.
Sound Frequency and Aural Selectivity in Sound-Contingent Visual Motion Aftereffect
PLoS ONE, 2012
Background: One possible strategy to evaluate whether signals in different modalities originate from a common external event or object is to form associations between inputs from different senses. This strategy would be quite effective because signals in different modalities from a common external event would then be aligned spatially and temporally. Indeed, it has been demonstrated that after adaptation to visual apparent motion paired with alternating auditory tones, the tones begin to trigger illusory motion perception to a static visual stimulus, where the perceived direction of visual lateral motion depends on the order in which the tones are replayed. The mechanisms underlying this phenomenon remain unclear. One important approach to understanding the mechanisms is to examine whether the effect has some selectivity in auditory processing. However, it has not yet been determined whether this aftereffect can be transferred across sound frequencies and between ears.
Sound-induced flash illusion as an optimal percept
Neuroreport, 2005
Recently, it has been shown that visual perception can be radically altered by signals of other modalities. For example, when a single £ash is accompanied by multiple auditory beeps, it is often perceived as multiple £ashes. This e¡ect is known as the soundinduced £ash illusion. In order to investigate the principles underlying this illusion, we developed an ideal observer (derived using Bayes' rule), and compared human judgements with those of the ideal observer for this task. The human observer's performance was highly consistent with that of the ideal observer in all conditions ranging from no interaction, to partial integration, to complete integration, suggesting that the rule used by the nervous system to decide when and how to combine auditory and visual signals is statistically optimal. Our ¢ndings show that the sound-induced £ash illusion is an epiphenomenon of this general, statistically optimal strategy. NeuroReport 16:1923^1927 c 2005 Lippincott Williams & Wilkins.
Auditory motion affects visual motion perception in a speeded discrimination task
Experimental Brain Research, 2007
Transient auditory stimuli have been shown to influence the perception of ambiguous 2D visual motion displays (the bouncing-disks effect; e.g. Sekuler et al. in Nature 385:308, 1997). The question addressed here was whether continuous moving auditory stimuli can also influence visual motion perception under the same experimental conditions. In Experiment 1, we used a modification of Sanabria et al.’s (Exp Brain Res 157:537–541, 2004) paradigm (involving an indirect behavioural measure of the bouncing-disks effect), in which the 2D visual display was presented together with either a brief tone, a continuous moving sound, or in the absence of any form of auditory stimulation. Crucially, the results showed that, together with the effect of the brief tone on bouncing trials, the presence of the continuous moving sound speeded-up participants’ responses on streaming trials as compared to the brief tone or no sound conditions. The results of a second experiment revealed that the effect of the continuous moving sound reported in Experiment 1 was not caused simply by the presence of continuous auditory stimulation per se.