Individual differences in directional bands in median plane localization

Blauert and other researchers demonstrated that the direction of a sound image for a narrow-band noise is perceived according to the center frequency of the stimuli. Blauert referred to the frequency band by which the direction of sound image is determined as the directional band. However, it has not yet been clarified if individual differences exist in the directional bands. It is also unestablished whether the directional band changes according to the bandwidth of the stimuli. In this study, 1/3 and 1/6 octave band noises were presented from the front, above and behind the subject in the median plane, and the responses to the stimuli were analyzed individually. The results show that (1) individual differences in directional bands exist; (2) there is no remarkable difference between directional bands for 1/3 and 1/6 octave band noises; (3) for some subjects, a directional band occurs in the direction in which they could not localize wide-band noise.