Correlations of decision weights and cognitive function for the masked discrimination of vowels by young and old adults

Abstract

Older adults are often reported in the literature to have greater difficulty than younger adults understanding speech in noise [Helfer and Wilber (1988). J. Acoust. Soc. Am, 859–893]. The poorer performance of older adults has been attributed to a general deterioration of cognitive processing, deterioration of cochlear anatomy, and/or greater difficulty segregating speech from noise. The current work used perturbation analysis [Berg (1990). J. Acoust. Soc. Am., 149–158] to provide a more specific assessment of the effect of cognitive factors on speech perception in noise. Sixteen older (age 56–79 years) and seventeen younger (age 19–30 years) adults discriminated a target vowel masked by randomly selected masker vowels immediately preceding and following the target. Relative decision weights on target and maskers resulting from the analysis revealed large individual differences across participants despite similar performance scores in many cases. On the most difficult vowel discriminations, the older adult decision weights were significantly correlated with inhibitory control (Color Word Interference test) and pure-tone threshold averages (PTA). Young adult decision weights were not correlated with any measures of peripheral (PTA) or central function (inhibition or working memory).

Empirical Non-Parametric Estimation of the Fisher Information

“…However, the statistical model is often unknown or the covariance computation may be intractable to manipulate. In some cases, for example in experimental design, one has access to a generative model, a black box that can generate multiple realizations from a distribution for various settings of its parameters, e.g., when one can generate data from a controlled experiment with accessible and tunable operating parameters [4], [5], [6]. In such cases it makes sense to try and compute the FIM empirically from multiple perturbed experiments.…”

Estimates of decision weights and internal noise in the masked discrimination of vowels by young and elderly adults

“…Lutfi and Liu, 2011). Notwithstanding, Gilbertson and Lutfi (2014) report for a randomly selected subset of these listeners that the decision weights were highly replicable over time. An two-way analysis of variance (ANOVA) (F0 Â group) of the d Plotting the data as in Fig.…”

“…Perturbation analysis was used to evaluate the relative influence of selective attention as given by the obtained decision weights and internal noise [for complete development of this analysis, the reader is referred to the papers by Lutfi and Liu (2011) and Gilbertson and Lutfi (2014)]. A logistic regression was performed on the trial-by-trial data for the probability of an interval one response with the interval difference (firstsecond) in F2 of target and masker as predictor variables.…”

“…Our interest then is in their relative contribution as estimated from the regression. Gilbertson and Lutfi, 2014) is that the effect of the decision weights on performance for the two groups can be directly evaluated. To this end, the d for both age groups and both listening conditions.…”

“…The stimuli, procedure, and participants of Gilbertson and Lutfi (2014) were used for the present study. The stimuli were masker-target-masker triads of synthesized vowels presented in a two-interval, forced-choice task (Neary, 1989;Hawks and Miller 1995;Klatt and Klatt, 1990).…”