An Energy Detection Model for Monaural Auditory Detection

Abstract

In the presence auditory detection of a sinusoidal signal in the presence of random noise, it has previously been demonstrated that the presence of a “pedestal” or background sinusoidal of the same frequency and phase as the signal increases detectability. This increase was confirmed in a two interval forced choice experiment in which a 1000-cps sinusoid was present in our of two 0.1-sec intervals, and the noise plus pedestal were present in both intervals. Pedestals of moderate intensity in phase with the signal increased detectability. Pedestals 90° out of phase with the signal did not improve detectability. Very large pedestals decreased detectability regardless of phase. A simple energy detection model was developed and its performance compared with the experimental results. The model consists of a bandpass filter, a rectifier or square-law element, and an integrator. The probability of correct detection varies with signal in a manner similar to the auditory results. Detectability is improved by an inphase pedestal and approaches that of a correlation detector in the limit of infinite pedestal. Detectability is not improved by 90° out-of-phase pedestals. However, the model does not predict decreasing detectability with large pedestals.

Evidence of stochastic resonance in an auditory discrimination task may reflect response bias

“…An additional experiment, Experiment 3, indicates The most likely form of response bias in Experiment 1 would be a bias toward the interval containing the noise burst. In this respect, participants are behaving as energy detectors, selecting the observation interval containing the greater amount of energy (Pfafflin & Mathews, 1962). Even this explanation, however, fails to account for the results obtained across the range of noise levels, and the nature of the bias is likely to be multifaceted.…”

Vibrotactile masking: Effects of oneand two-site stimulation

“…intensities below the threshold level of the test stimulus. This phenomenon has been called "negative masking," which has been demonstrated in auditory experiments (D. M. Green, 1960;Leshowitz & Raab, 1967;Pfafflin & Mathews, 1962;Raab, Osman, & Rich, 1963a, 1963bTanner, 1961) and recently in vibrotactile experiments (Hamer, 1979;Hamer, Verrillo, & Zwislocki, in press). Negative masking remained after the data were converted to effective energy thresholds in Hamer's data and in ours.…”

Nonparametric Relationships between Single-Interval and Two-Interval Forced-Choice Tasks in the Theory of Signal Detectability

“…Observer inconsistency has been characterized by using the concepts of internal and external noise, where the emphasis is on the sources or causes of noise, or error, in experimental tasks (e.g., Green, 1964a;Pfafflin & Mathews, 1962;Raab & Goldberg, 1975). An alternative approach is to use the concepts of unique and common noise, which emphasize the statistical components or effects of error rather than the sources of error (Drga, 1999;Boven, 1976;Taylor, 1984;Taylor et al, 1991).…”