title: Enhancement of response times to bi- and tri-modal sensory stimuli during active movements.
abstract: Simultaneous activation of two sensory modalities can improve perception and enhance performance. This multi-sensory enhancement had been previously observed only in conditions wherein participants were not performing any movement. Since tactile perception is attenuated during active movements, we investigated whether a bi- and a tri-modal enhancement can occur also when participants are presented with tactile stimuli, while engaged in active movements. Participants held a pen-like stylus and performed bidirectional writing-like movements inside a restricted workspace. During these movements participants were given a uni-modal sensory signal (visual--a thin gray line; auditory--a brief sound; haptic--a mechanical resisting force delivered through the stylus) or a bi- or tri-modal combination of these uni-modal signals, and their task was to respond, by pressing a button on the stylus, as soon as any one of these three stimuli was detected. Results showed that a combination of tri-modal signals was detected faster than any of the bi-modal combinations, which in turn were detected faster than any of the uni-modal signals. These facilitations exceeded the "Race model" predictions. A breakdown of the time gained in the bi-modal combinations by hemispace, hands and gender, provide further support for the "inverse effectiveness" principle, as the maximal bi-modal enhancements occurred for the least effective uni-modal responses.
authors.affiliation: The Touch Laboratory, Department of Education in Technology and Science, Technion - Israel Institute of Technology, Gutwirth Building, Haifa 32000, Israel. davidh@tx.technion.ac.il
authors.forename: David
authors.initials: D
authors.lastname: Hecht
authors.forename: Miriam
authors.initials: M
authors.lastname: Reiner
authors.forename: Avi
authors.initials: A
authors.lastname: Karni
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D010812:Physical Stimulation / Q000379:methods; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology*; D014110:Touch / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*