Rh. Dye et al., STIMULUS CLASSIFICATION PROCEDURE FOR ASSESSING THE EXTENT TO WHICH BINAURAL PROCESSING IS SPECTRALLY ANALYTIC OR SYNTHETIC, The Journal of the Acoustical Society of America, 96(5), 1994, pp. 2720-2730
A two-dimensional stimulus classification paradigm was used to assess
the extent to which listeners' processing of interaural delays at low
frequencies is spectrally analytic or synthetic. Listeners were presen
ted with a 753-Hz target with an interaural delay that varied from tri
al to trial, taking on one of ten values, five leading to the left ear
and five leading to the right. A 553-Hz distracter component was simu
ltaneously presented, with its interaural delay also presented at one
of ten different values. During a block of 100 trials, each of the pos
sible combinations of target and distracter delay was presented once,
and only once, in a random order. Listeners were instructed to make le
ft-right judgments based on the target delay. Each condition was repea
ted ten times, and the slopes of the best linear boundaries between le
ft and right responses were used to derive the relative weights given
to the target and distracter in judgments of laterality. Six of the ni
ne listeners gave increasing weight to the target as the duration of t
he signals was increased from 25 or 50 to 400 ms. Three listeners show
ed little change with duration; one consistently gave equal weight to
the target and distracter, two consistently gave greater weight to the
target than to the distracter. The utility of classification paradigm
s in the study of multidimensional acoustic signals is discussed.