Psychometric functions for gap detection in a yes–no procedure

Abstract

To examine models of temporal resolution and to investigate the decision processes underlying the detection of a brief pause in a bandpass noise, psychometric functions for gap detection were measured at octave frequencies from 0.25 to 8 kHz. Three normal listeners were tested using a constant-stimulus procedure with a cued Yes-No paradigm. The Minimum Detectable Gap (MDG) estimated from the midpoint of the psychometric functions decreased systematically with increasing frequency. The slopes of the psychometric functions generally increased as the test frequency increased up to 2 kHz, but remained constant at the higher frequencies. Two models were investigated: an energy-detector model and a loudness-detector model. Both consisted of auditory filtering, a nonlinearity, and short-term integration. In the energy-detector model, the nonlinearity was a square law. In the loudness-detector model, it was a compressive power law. Using the usual Gaussian approximations, the energy-detector model fails at low frequencies because the probability distributions of short-term energy differ from Gaussian distributions. The probability distributions of short-term loudness closely follow Gaussian distributions. The loudness-detector model predicts the frequency dependence of the MDG quite accurately, except at 0.25 kHz. It also predicts psychometric functions that resemble the data at low frequencies, but the predicted slopes increase much less with frequency than the measured slopes. This result may indicate that the onset response to the trailing marker of the gap provides an important cue for detection of gaps with durations exceeding the MDG.

Rhythmicity and cross-modal temporal cues facilitate detection

“…2; average explained variance 98.6%; see e.g. Florentine, Buus, & Geng, 1999; Green, 1995; Nachmias, 1981). The analysis using average 50% detection levels of the fitted psychometric functions (Fig.…”

Age-related differences in the temporal modulation transfer function with pure-tone carriers

“…Given the reciprocal nature of the relationship between temporal resolution and filter bandwidth, temporal resolution would be expected to be better at higher than lower center frequencies. However, temporal resolution as measured by gap detection does not vary greatly with frequency, except for very low and very high frequencies (Florentine et al, 1999). In addition, auditory filtering as inferred by critical band analysis does not reflect the fact that neural firings are synchronized to the period of the signal (phase locking); neural phase locking is strong at low frequencies and decreases as frequency increases (Rose et al, 1967).…”

Controvérsias ou complexidade na relação entre processamento temporal auditivo e envelhecimento?

“…Além dos estudos em que se procura determinar os limiares de detecção de interrupções, existem trabalhos descrevendo as funções psicométricas de detecção de interrupções com uso de procedimentos sim-não, utilizando tons puros 5 , ruídos com bandas largas de freqüência 6 e bandas estreitas de ruídos 7 . Tais estudos são descritos com mais detalhes em texto de Neves e Feitosa (2002, no prelo).…”