Do “mudsplashes” induce tactile change blindness?

Abstract

The phenomenon of change blindness (the surprising inability of people to correctly perceive changes between consecutively presented displays), primarily reported in vision, has recently been shown to occur for positional changes presented in tactile displays as well. Here, we studied people's ability to detect changes in the number of tactile stimuli in successively presented displays composed of one to three stimuli distributed over the body surface. In Experiment 1, a tactile mask consisting of the simultaneous activation of all seven possible tactile stimulators was sometimes presented between the two to-be-discriminated tactile displays. In Experiment 2, a "mudsplash" paradigm was used, with a brief irrelevant tactile distractor presented at the moment of change of the tactile display. Change blindness was demonstrated in both experiments, thus showing that the failure to detect tactile change is not necessarily related to (1) the physical disruption between consecutive events, (2) the effect of masking covering the location of the change, or (3) the erasure or resetting of the information contained within an internal representation of the tactile display. These results are interpreted in terms of a limitation in the number of spatial locations/events that can be consciously accessed at any one time. This limitation appears to constrain change-detection performance, no matter the sensory modality in which the stimuli are presented.

Change perception in complex auditory scenes

“…The present results show that the aSTM capacity is severely limited, and they are in line with those of Luck and Vogel (1997) for the visual modality and those of Gallace et al (2007) for the tactile modality. Although participants In the General Discussion, we will discuss why auditory transients, at least in the present paradigm, seem to play no role in auditory change detection.…”

“…Participants were instructed to decide whether the single a complex auditory scene consisting of multiple auditory objects of the same category (i.e., animal calls), change deafness occurred even for a small number of auditory objects. This finding is similar to what has been reported recently in the tactile modality (e.g., Gallace et al, 2007). Second, change deafness was higher for object disappearance than for object appearance, a result that can parsimoniously be related to the lesser complexity of the first auditory scene on addition than on deletion trials.…”

“…Instead of cycling the two scenes continuously until listeners found the change-as is the case in the standard Flicker technique adopted for many change blindness studies (Rensink et al, 1997)-the authors used the "oneshot technique" (Gallace et al, 2007;Phillips, 1974;Rensink, 2000). This technique consists of the presentation of a single pair of events (here auditory scenes) in each experimental trial, and participants are required to detect any difference between the two.…”

“…In other words, at the moment of change, most (if not all) auditory stimuli in the scene changed with respect to the previous time instant. Adopting the terminology of the literature on change blindness, this would be the auditory analogue of the mudsplash phenomenon (Gallace, Auvray, et al, 2006;Gallace et al, 2007;O'Regan et al, 1999), in which the change-related (task-relevant) transient is swamped by multiple and competing "extraneous" transients. An interesting difference to note is that, whereas in the visual and in the tactile change blindness paradigms, the extraneous transients (i.e., mudsplashes) are purposefully and artificially introduced by the experimenter into an otherwise static scene (in vision or touch), in the change deafness paradigm, they are the natural result of the dynamic nature of complex auditory scenes that change and develop over time.…”

The Body Surface as a Communication System: The State of the Art after 50 Years

“…Recent research has also provided the first evidence of a tactile analog of the phenomenon of change blindness (see Gallace, Tan, Spence, 2005, 2007a, with participants failing to detect a significant proportion (up to 30%) of positional changes between two consecutively presented tactile patterns even when separated by intervals as short as 110 ms and when a distractor was presented between the two to-be-compared tactile patters (see Figure 2). Interestingly, in Gallace et al's (2005Gallace et al's ( , 2006bGallace et al's ( , 2007a) studies, the failure to detect changes to tactile stimuli presented over the body surface was observed when no more than two to three tactors were activated.…”