Speech Responses and Dual-Task Performance: Better Time-Sharing or Asymmetric Transfer?

Abstract

It has been proposed that using speech controls could improve time-sharing efficiency in environments previously dominated by manual controls (e.g., military aviation). However, it has been suggested that the research supporting the use of speech controls was potentially contaminated by asymmetric transfer. The present study examined the value of speech controls in a dual-task experiment that also evaluated asymmetric transfer effects. Despite significant effects supporting the advantage of mixing manual and speech responses, there was no evidence of asymmetric transfer. Thus although asymmetric transfer remains an experimental design concern, it is not a sufficient explanation for the observed response modality effects. The results suggested that speech controls can be used to enhance performance in operational multiple-task environments.