Monaural detection with contralateral cue (MDCC). IV. Psychometric functions with sinusoidal signals.

Abstract

Detection performance in the monaural detection with contralateral cue (MDCC) task was measured for sinusoidal signals over a range of signal-masker levels at several cue intensities and phases. In the first experiment, the effect of cue intensity was measured at two phases, one giving good performance and the other leading to poor performance. With good phase, cue intensity had little effect except that performance declined with a very loud or very soft cue. With bad phase, increasing the cue intensity made performance worse. Over a considerable range of cue intensity and signal-masker level, bad-phase performance was well below chance. In the second experiment, the effect of cue phase was determined at a single cue intensity. Performance was an asymmetrical function of cue phase. The slopes of the derived psychometric functions were also a function of phase, approximating the slope of an ideal detector for signal known exactly (SKE) when phase was good, and approximating that of the simple monaural detection psychometric function when the phase was bad. The data lend support to the idea that binaural interaction involves at least two independent mechanisms.