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The Colavita visual dominance effect refers to the phenomenon where participants respond more often to the visual component of an audiovisual stimulus, when presented with bimodal stimuli.〔Hartcher-O’Brien, J., Levitan, C., Spence, C. (2010)〕 Research has shown that vision is the most dominant sense for human beings 〔Posner, M.I., Nissen, M.J., Klein, M., (1976)"Visual Dominance:An Information Processing Account of its Origins and Significance" Psychological Review, 83(2):157-171〕 who do not suffer from sensory difficulties (e.g. blindness, cataracts). Theorists have proposed that the Colavita visual dominance effect demonstrates a bias toward visual sensory information, because the presence of auditory stimuli is commonly neglected during audiovisual events. Francis B. Colavita, whom the Colavita visual dominance effect is aptly named after, was the first to demonstrate this phenomenon in 1974. Colavita's original experiments found that visual dominance for audiovisual events persists under a number of conditions, which has been further established as a robust effect by other researchers. ==The Colavita visual dominance effect== In 1974, Francis B. Colavita conducted an experiment, which provided evidence for visual dominance in humans when performing an audiovisual discrimination task.〔Colavita, F.B. (1974). Human sensory dominance. Perception & Psychophysics,16(2), 409-412.〕 In his seminal experiment, Colavita (1974) presented participants with an auditory (tone) or visual (light) stimulus, to which they were instructed to respond by pressing the ‘tone key’ or ‘light key’ respectively.〔 Throughout the experiment, unimodal auditory trials, unimodal visual trials and a small number of audiovisual bimodal trials were randomly presented.〔 Colavita deceived the participants by informing them that the bimodal trials in the experiment occurred “accidentally”.〔 During practice trials, Colavita would “accidentally” present audiovisual stimuli, and would then draw the participants’ attention to what had just happened and would apologize for such ‘accident’.〔 In addition, the participants were not instructed on how to respond on such trials or whether this type of trials would occur again 〔Koppen C., Spence C. (2007a). Seeing the light: exploring the Colavita visual dominance effect. Experimental Brain Research 180,737–754.〕 The results showed that participants had almost equivalent response times for auditory and visual stimuli in unimodal trials.〔 Additionally, Colavita found that participants pressed the ‘light key’ in the majority of the bimodal trials. This was seen as evidence of visual dominance because participants failed to acknowledge the presence of the auditory stimulus in most bimodal trials.〔〔 However, due to Colavita’s deception of the “accidental” occurrence of bimodal trials, researchers have proposed that experimenter expectancy effects, task demands or methodological problems may have contributed to the visual dominance effect reported in Colavita’s original study.〔Sinnett, S., Spence, C. & Soto-Faraco, S. (2007).Visual Dominance and attention: The Colavita effect revisited. Perception and Psychophysics, 69(5), 673-686.〕 Nevertheless, subsequent experiments have discontinued the use of deception, and continue to show a robust Colavita visual dominance effect.〔 For example, Sinnet and his colleagues conducted an experiment in which they presented participants with three response keys, one for each type of response (unimodal visual, unimodal auditory and bimodal audiovisual); instead of just two, and they instructed participants to press the bimodal key when responding to audiovisual stimuli.〔 This new manipulation resulted in a significant reduction of the Colavita effect because errors in bimodal trials were only committed in a small number of trials.〔 In another experiment, Sinnett and his colleagues conducted a pre-specified target detection task where auditory targets were more frequent than visual or bimodal targets. This led to the elimination of the Colavita effect. The authors suggested that this was due to the introduction of a bias toward auditory stimuli.〔Koppen, C. & Spence, C. (2007b). Audiovisual asynchrony modulates the Colavita visual dominance effect. Brain Research, 1186, 224-232.〕 Ngo and her colleagues conducted a similar study where the results were replicated, because their findings showed that under the appropriate conditions and task demand, the Colavita effect can be reversed.〔Ngo, M.K., Cadieux, M.L., Sinnett, S., Soto-Faraco, S. & Spence, C. (2011). Reversing the Colavita visual dominance effect. Experimental Brain Research, 214, 607-618.〕 Also, Sinnett and his colleagues mention that animals and humans increase their reliance on auditory stimuli in high-arousal situations and when facing potential threats,〔 which could imply that the Colavita effect is situation and context dependent. Colavita also varied the intensity of the visual and the auditory stimuli to determine whether matching the intensity of both stimuli, or if increasing the intensity of only the auditory stimulus would decrease the occurrence of the Colavita effect.〔 However, none of the experimental manipulations regarding the intensity of the stimuli decreased the occurrence of the Colavita effect.〔 Further research has been conducted to replicate Colavita’s experiment and to extend the Colavita effect to more complex stimuli. For example, Sinnett, Spence and Soto-Faraco conducted an experiment in 2007, in which pictures and sounds were used as stimuli instead of the light and tone.〔 The rationale for using more complex stimuli was that this type of stimuli would increase (perceptual load ), requiring more attentional resources.〔Lavie, N. (2005). Distracted and Confused? Selective attention under load. Trends in Cognitive Sciences, 9(2), 75-82.〕 The findings from this study showed that the Colavita effect continues to occur when stimuli become more complex. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Colavita visual dominance effect」の詳細全文を読む スポンサード リンク
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