Cognitive aging and hearing acuity: modeling spoken language comprehension

Abstract

The comprehension of spoken language has been characterized by a number of “local” theories that have focused on specific aspects of the task: models of word recognition, models of selective attention, accounts of thematic role assignment at the sentence level, and so forth. The ease of language understanding (ELU) model (Rönnberg et al., 2013) stands as one of the few attempts to offer a fully encompassing framework for language understanding. In this paper we discuss interactions between perceptual, linguistic, and cognitive factors in spoken language understanding. Central to our presentation is an examination of aspects of the ELU model that apply especially to spoken language comprehension in adult aging, where speed of processing, working memory capacity, and hearing acuity are often compromised. We discuss, in relation to the ELU model, conceptions of working memory and its capacity limitations, the use of linguistic context to aid in speech recognition and the importance of inhibitory control, and language comprehension at the sentence level. Throughout this paper we offer a constructive look at the ELU model; where it is strong and where there are gaps to be filled.

The Neural Consequences of Age-Related Hearing Loss

“…Further, although it typically goes unnoticed, everyday speech is surprisingly underarticulated, such that many words would be totally unidentifiable if not heard with the support of acoustic and linguistic context [7,8]. 1 Adding to the challenges of rapid input rate and variable speech quality, the act of comprehension places a heavy demand on working memory to keep track of a conversation from sentence to sentence and to untangle syntactically complex speech [10]. …”

Effects of Age, Acoustic Challenge, and Verbal Working Memory on Recall of Narrative Speech

“…Such a buffering mechanism could be carried by verbal working memory, which has been suggested to support the processing of difficult-to-understand speech (Rönnberg et al, 2013; Wingfield, Amichetti, & Lash, 2015). If verbal working memory is indeed required for perceptual processing, it will be less available to encode heard items into memory.…”

Sensory and cognitive contributions to age‐related changes in spoken word recognition

“…One recurring theme in cognitive hearing science is that listeners recruit working memory, inhibition, and other cognitive resources to aid in speech perception when auditory processes struggle or fail (e.g., Arlinger et al, 2009;Rönnberg, Rudner, & Lunner, 2011;Schneider et al, 2002;Stanley et al, 2012;Wingfield, Amichetti, & Lash, 2015). Two models have been proposed to explain this relationship: the Effortfulness Hypothesis (Rabbitt, 1968;Wingfield et al, 2005) and the Ease of Language Understanding model .…”

“…The ELU posits that word identification proceeds automatically and effortlessly when the multimodal input matches a word stored in long-term memory, but when there is not a clear match, then word recognition becomes effortful and additional resources are recruited. Evidence supporting the ELU comes in part from findings that for hearing-impaired listeners, better working memory capacity is related to better performance on rhyme judgments (e.g., Classon, Rudner, Johansson, & Rönnberg, 2013; see Wingfield et al (2015) for a more detailed review and critique of the ELU). Breakdowns in automatic processing can occur due to idiosyncrasies in the signal (e.g., if a speaker pronounces a word in an atypical manner; Van Engen & Peelle, 2014), or when high-frequency hearing loss limits the acoustic information available for matching the signal to words in long-term memory (Humes, 1996).…”