Abstract
Detecting changes in a dynamic and complex environment is a resource intensive and time consuming task. However, the search times of change in stationary visual objects can be dramatically decreased by brief nonspatial auditory signals that are presented simultaneously to the change – called pip-and-pop effect (van der Burg et al., 2008). Here, we compared effects of auditory, tactile, and audio-tactile signals on change detection in moving visual stimuli. In the visual display (52.8° by 31.2°) 8 visual objects (radius: 0.2° visual angle) were moving in horizontal and vertical directions. In half of the trials, one visual object changed its movement direction by 90° or 270° at a random time point after trial onset (5- 6 seconds). Participants had to detect the directional change as fast and accurate as possible in four cue conditions. These were auditory, tactile, audiotactile, or no cue which slightly preceded the change and presented for 100ms. The auditory cue was a sine-wave sound of 440 Hz frequency delivered through headphones, and the tactile cue was a 160 Hz-vibration delivered through four actuators of a vibrotactile vest on the front and back of the torso . In audio-tactile condition, auditory and tactile cue were combined. All three types of cues – auditory, tactile, and audio-tactile – improved the detection accuracy in terms of d-prime and decreased response times as compared to the no cue condition. Taken together, we demonstrated that the pip-and-pop effect is a more general phenomenon than previously shown: We extended the observation of cue-triggered pop-out to the detection of change in moving stimuli and found a haptic analogue, the tap-and-pop effect.