title: Effects of variations in force and stimulus uncertainty on fractionated reaction time.
abstract: Previous research has shown that reaction time (RT) and premotor time varied as a function of force even in simple-RT paradigm. The present purpose was to examine whether stimulus uncertainty induced by catch trials would cause programming delay until after the signal to respond. Subjects were required to react and produce a designated peak force as soon as possible after a visual stimulus, with and without catch trials. Five different levels of force were 10, 30, 50, 70, and 90% of the maximum grip strength of subjects. Analysis showed that simple RT and premotor time changed as a function of force, regardless of whether catch trials were removed. These findings suggest that stimulus uncertainty is not a necessary condition for programming delay.
authors.affiliation: Department of Health and Physical Education, Faculty of Education, Shinshu University, Nagano City, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ito
mesh_terms: D000328:Adult; D001288:Attention; D005260:Female; D006801:Humans; D007699:Kinesthesis; D008297:Male; D011939:Mental Recall; D005082:Physical Exertion; D011597:Psychomotor Performance; D011601:Psychophysics; D011930:Reaction Time