Dependence of apparent rate of alternating clicks on azimuthal separation between sources

Ten listeners compared the apparent rate of 10/sec clicks, presented alternately from two comparison sources separated horizontally by 12–168 deg with that of clicks presented alternately from standard sources separated by 180 deg. The apparent rate of comparison clicks increased monotonically with decrease in angular separation. This result is consonant with the hypothesis that repetitive shifts of attention between two sound sources depend importantly on oscillating motor adjustments.