Speech Perception Under Adverse Listening Conditions

Abstract

Perceiving and understanding spoken language is something that most listeners take for granted, at least in favorable listening conditions. Yet, decades of research have demonstrated that speech is variable and ambiguous, meaning listeners must constantly engage in active hypothesis testing of what was said. Within this framework, even relatively minor challenges imposed on speech recognition must be understood as requiring the interaction of perceptual, cognitive, and linguistic factors. This chapter provides a systematic review of the various ways in which listening environments may be considered adverse, with a dual focus on the cognitive and neural systems that are thought to improve speech recognition in these challenging situations. Although a singular mechanism or construct cannot entirely explain how listeners cope with adversity in speech recognition, overcoming listening adversity is an attentionally guided process. Neurally, many adverse listening conditions appear to depend on higher-order (rather than primary) representations of speech in cortex, suggesting that more abstract linguistic knowledge and context become particularly important for comprehension when acoustic input is compromised. Additionally, the involvement of the cinguloopercular (CO) network, particularly the anterior insula, in a myriad of adverse listening situations may indicate that this network reflects a general indication of cognitive effort. In discussing the various challenges faced in the perception and understanding of speech, it is critically important to consider the interaction of the listener’s cognitive resources (knowledge and abilities) with the specific challenges imposed by the listening environment.