Aging and Spectro-Temporal Integration of Speech

Abstract

The purpose of this study was to determine the effects of age on the spectro-temporal integration of speech. The hypothesis was that the integration of speech fragments distributed over frequency, time, and ear of presentation is reduced in older listeners—even for those with good audiometric hearing. Younger, middle-aged, and older listeners (10 per group) with good audiometric hearing participated. They were each tested under seven conditions that encompassed combinations of spectral, temporal, and binaural integration. Sentences were filtered into two bands centered at 500 Hz and 2500 Hz, with criterion bandwidth tailored for each participant. In some conditions, the speech bands were individually square wave interrupted at a rate of 10 Hz. Configurations of uninterrupted, synchronously interrupted, and asynchronously interrupted frequency bands were constructed that constituted speech fragments distributed across frequency, time, and ear of presentation. The over-arching finding was that, for most configurations, performance was not differentially affected by listener age. Although speech intelligibility varied across condition, there was no evidence of performance deficits in older listeners in any condition. This study indicates that age, per se, does not necessarily undermine the ability to integrate fragments of speech dispersed across frequency and time.

How repetition influences speech understanding by younger, middle-aged and older adults

“…As can be observed in Table 1 and Figure 4, repetition benefit in the presence of the SEM noise masker was slightly (but not statistically significantly) larger for target-repeat trials than for target + masker repeat trials for the two older groups. Studies of speech perception using interrupted target speech or a modulated masker have not reached consensus regarding whether aging interferes with the ability to integrate glimpses within a trial (e.g., Gordon-Salant and Fitzgibbons, 1993; Dubno et al, 2003; Grose et al, 2009; Fullgrabe et al, 2015; Shafiro et al, 2015; Grose et al, 2016). How aging affects the ability to integrate glimpses of speech across trials remains to be seen.…”

Natural products present neurotrophic properties in neurons of the limbic system in aging rodents

“…(For the interpretation of the references to color in this figure legend, the reader can refer to the web version of this article) the limbic system. In the same way, several reports suggest that aging is a physiological process that occurs asynchronously in different areas of the brain (Chung et al, 2017;Erickson et al, 2014;Grose, Porter, & Buss, 2016;Mora, Segovia, & del Arco, 2007;Sánchez, Gómez-Villalobos, Juarez, Quevedo, & Flores, 2011;Tamnes et al, 2013). For example, in spontaneously hypertensive (SH) rats, an animal model of premature aging, pyramidal neurons of the PFC, and medium spine neurons (MSN) of the NAcc showed a reduction in the number of dendritic spines at 4 months of age.…”

Dichotic spectral integration range for consonant recognition in listeners with normal hearing

“…Normal hearing (NH) listeners receive the same or similar auditory input from each ear, and the input is then sent to the higher auditory system for further processing, such as spectral integration ( Ronan et al, 2004 ; Hall et al, 2008 ; Fox et al, 2011 ; Räsänen and Laine, 2013 ; Grose et al, 2016 ). However, individuals with hearing loss may receive different spectral information from each ear and are forced to integrate them across the ears, that is, dichotic spectral integration ( Tononi, 2010 ; Kong and Braida, 2011 ; Yang and Zeng, 2013 ; Reiss et al, 2014 ; Obuchi et al, 2015 ).…”