Fast and accurate measurement of taste and smell thresholds using a maximum-likelihood adaptive staircase procedure

Abstract

This paper evaluates the use of a maximum-likelihood adaptive staircase psychophysical procedure (ML-PEST), originally developed in vision and audition, for measuring detection thresholds in gustation and olfaction. The basis for the psychophysical measurement of thresholds with the ML-PEST procedure is developed. Then, two experiments and four simulations are reported. In the first experiment, ML-PEST was compared with the Wetherill and Levitt up-down staircase method and with the Cain ascending method of limits in the measurement of butyl alcohol thresholds. The four Monte Carlo simulations compared the three psychophysical procedures. In the second experiment, the test-retest reliability of ML-PEST for measuring NaCl and butyl alcohol thresholds was assessed. The results indicate that the ML-PEST method gives reliable and precise threshold measurements. Its ability to detect malingerers shows considerable promise. It is recommended for use in clinical testing.

Olfactory Impairments in Patients with Unilateral Cerebellar Lesions Are Selective to Inputs from the Contralesional Nostril

“…Olfactory thresholds for the two tested odorants were determined for each nostril using a maximum-likelihood adaptive staircase procedure modeled after Linschoten et al (2001). The participants were blindfolded for this task.…”

Threshold estimation in two-alternative forced-choice (2AFC) tasks: The Spearman-Kärber method

“…On the basis of this conceptualization of the 2AFC task, the researcher estimates the parameters of the distribution assumed for F(x) and summarizes performance in terms of the estimated distribution. Traditionally, the threshold has been taken as the median of this distribution [i.e., the value of x for which F(x) ϭ .5; see, e.g., Linschoten et al, 2001;Wichmann & Hill, 2001; for a review, see Gescheider, 1997]. As will be discussed further below, however, it is possible that the mean should be used instead of the median.…”

“…Psychophysicists often prefer this procedure over the classical yes-no task for determining thresholds, because the 2AFC procedure discourages response biases and also produces an especially high level of performance (e.g., Gescheider, 1997;Linschoten, Harvey, Eller, & Jafek, 2001; for a detailed review, see Macmillan & Creelman, 1991, chap. 5).…”

“…Note that the location parameter α is both the mean and the median of the logistic distribution, so this parameter is usually referred to as the threshold in studies assuming the logistic function (see Linschoten et al, 2001). The parameters α and β in Equation 2 can be estimated by the maximum likelihood method (e.g., Harvey, 1986;Treutwein & Strasburger, 1999).…”

Design and results of the pretest of the IDEFICS study

“…Standardised methods, commonly used by the food industry to assess acceptance of new food products, need to be adapted for use on children. 18 For the measurement of taste preferences, the children were offered two glasses, one filled with cherry juice with its normal taste and the other filled with cherry juice with an added taste component. The basic taste was tested pairwise against added sugar or sugar plus aroma.…”