Illusory double flashes can speed up responses like physical ones: evidence from the sound-induced flash illusion.
ABSTRACT When a single brief flash is accompanied by two auditory beeps, participants often report perceiving two flashes. The present experiment examined whether the perception of illusory redundant flashes can result in faster responses as compared to the perception of a single flash, because previous research has shown such a redundancy gain for physical stimuli. To this end, participants were asked to respond as rapidly as possible to the onset of any flash. Following their response, they additionally indicated whether they perceived a single flash or a double flash. Most importantly, we observed significant shorter reaction times in response to redundant flashes, irrespective of whether they were physically presented or illusorily perceived. Taken together, our results suggest that an illusory percept can affect simple reaction time in much the same manner as the corresponding physical stimulation.
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ABSTRACT: In four experiments, increasing the intensities of both relevant and irrelevant auditory stimuli was found to increase response force (RF) in simple, go/no-go, and choice reaction time (RT) tasks. These results raise problems for models that localize the effects of auditory intensity on purely perceptual processes, indicating instead that intensity also affects motor output processes under many circumstances. In Experiment 1, simple RT, go/no-go, and choice RT tasks were compared, using the same stimuli for all tasks. Auditory stimulus intensity affected both RT and RF, and these effects were not modulated by task. In Experiments 2-4, an irrelevant auditory accessory stimulus accompanied a relevant visual stimulus, and the go/no-go and choice tasks were used. The intensity of the irrelevant auditory accessory stimulus was found to affect RT and RF, although the sizes of these effects depended somewhat on the temporal predictability of the accessory stimulus.Perception & Psychophysics 02/1999; 61(1):107-19. · 1.37 Impact Factor
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ABSTRACT: A series of three visual choice-reaction time experiments were performed to systematically investigate the effects of accessory auditory stimulation on response time (RT) and response force (RF). In Experiment 1, the effect of accessory auditory stimulation on early visual information processing was investigated. Experiments 2 and 3 were designed to examine the effects of accessory intensity on RT and RF across the entire time course of sensorimotor processing. Accessory stimulation accelerated response speed only when presented within 100 ms after onset of the visual response signal. An enhancing effect of accessory stimulation on RF, however, was found as late as 220 ms after onset of the response signal. These findings support the notion that response speed and response dynamics represent functionally independent sensorimotor phenomena.Acta Psychologica 10/2005; 120(1):1-18. · 2.26 Impact Factor
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ABSTRACT: A number of studies have shown that while perceptual judgment is deceived by pictorial illusions, grasping and other kinds of motor behaviour are not. This is in keeping with the existence of two different cortical systems: a ventral stream subserving vision-for-perception and a dorsal stream subserving vision-for-action. The former is sensitive to illusions, the latter is not. Given this dissociation of functions, one wonders whether simple visuomotor reaction time (RT) follows the ventral or the dorsal rule in perceiving illusory figures. Answering this question might contribute to a better understanding of the different functions of the two systems. We carried out two experiments, one with the Ponzo and the other with the Ebbinghaus-Titchener illusion and found that RT is sensitive to both illusions with faster responses to stimuli appearing illusorily bigger than the others. These results show that motor action is subserved by the ventral system when that action directly reports the presence or onset of a target rather than when that action requires a spatial adjustment that reflects the physical features of the target.Experimental Brain Research 09/2009; 201(2):345-50. · 2.22 Impact Factor