Ear asymmetry in an auditory spatial Stroop task as a function of handedness.

A reaction-time (RT) experiment was carried out in which five groups consisting of subjects with various degrees of left and right handedness, participated. The words left and right were presented binaurally, one at a time, either to the left or to the right side, implying four presentation modes. The two interfering presentation modes are regarded as Stroop tasks. Two reaction conditions were applied in separate sessions; 1. reacting to the perceived location, and 2. reacting to the content of the word. With specific hypotheses concerning cerebral dominance for verbal functions in right-handed subjects, but considerably less clear anticipations with respect to left-handers, we obtained an interaction between side of presentation, Stroop effect and handedness. The results are discussed in terms of the relation between the conceptualization of space and cerebral dominance.