title: Right-left prevalence with task-irrelevant spatial codes.
abstract: The present work investigated the right-left prevalence effect caused by the automatic activation of horizontal and vertical spatial codes in a task (Simon task) in which spatial information is task-irrelevant. Experiment 1 showed a horizontal Simon effect and a vertical Simon effect with a two-dimensional stimulus-response set. In Experiments 2 and 3, the right-left prevalence was obtained in two-dimensional Simon tasks with two contralateral effectors and four effectors respectively. Experiment 4 showed that horizontal coding is based on multiple spatial codes, whereas only one spatial code was formed for vertical coding. On the whole, these results support the notion that the right-left prevalence effect is a general phenomenon affecting spatial coding, and suggest that the horizontal dimension is prevalent because it is based on multiple spatial codes.
authors.affiliation: Dipartimento di Scienze Sociali, Cognitive e Quantitative, Università di Modena e Reggio Emilia, Via Giglioli Valle 9, 42100 Reggio Emilia, Italy. rubichi@unimore.it
authors.forename: Sandro
authors.initials: S
authors.lastname: Rubichi
authors.forename: Roberto
authors.initials: R
authors.lastname: Nicoletti
authors.forename: Carlo
authors.initials: C
authors.lastname: Umiltà
mesh_terms: D000704:Analysis of Variance; D007839:Functional Laterality; D006801:Humans; D007558:Italy; D010056:Overlearning; D011597:Psychomotor Performance; D011930:Reaction Time; D013028:Space Perception