Contributions of Sensory Coding and Attentional Control to Individual Differences in Performance in Spatial Auditory Selective Attention Tasks

Abstract

Listeners with normal hearing thresholds (NHTs) differ in their ability to steer attention to whatever sound source is important. This ability depends on top-down executive control, which modulates the sensory representation of sound in the cortex. Yet, this sensory representation also depends on the coding fidelity of the peripheral auditory system. Both of these factors may thus contribute to the individual differences in performance. We designed a selective auditory attention paradigm in which we could simultaneously measure envelope following responses (EFRs, reflecting peripheral coding), onset event-related potentials (ERPs) from the scalp (reflecting cortical responses to sound) and behavioral scores. We performed two experiments that varied stimulus conditions to alter the degree to which performance might be limited due to fine stimulus details vs. due to control of attentional focus. Consistent with past work, in both experiments we find that attention strongly modulates cortical ERPs. Importantly, in Experiment I, where coding fidelity limits the task, individual behavioral performance correlates with subcortical coding strength (derived by computing how the EFR is degraded for fully masked tones compared to partially masked tones); however, in this experiment, the effects of attention on cortical ERPs were unrelated to individual subject performance. In contrast, in Experiment II, where sensory cues for segregation are robust (and thus less of a limiting factor on task performance), inter-subject behavioral differences correlate with subcortical coding strength. In addition, after factoring out the influence of subcortical coding strength, behavioral differences are also correlated with the strength of attentional modulation of ERPs. These results support the hypothesis that behavioral abilities amongst listeners with NHTs can arise due to both subcortical coding differences and differences in attentional control, depending on stimulus characteristics and task demands.

Sensorineural hearing loss degrades behavioral and physiological measures of human spatial selective auditory attention

“…These results are similar to past results in NH listeners showing that attentional modulation of cortical responses predicts individual performance on selective auditory attention tasks ( 18 , 22 , 25 ). The relationship between attentional modulation and spatial acuity found in the current study suggests that spatial acuity determines how “selective” attention to a stream from a particular location can be, which then impacts how strongly other streams from other locations will be suppressed.…”

“…Here, we used behavior and EEG to compare the efficacy of selective auditory attention in listeners with normal hearing and with bilateral, sloping sensorineural hearing loss. We used a previously published task in which listeners identify a simple melody presented simultaneously with two competing melodies at different spatial locations, while concurrently measuring EEG ( 15 , 22 ). By design, early cortical responses to notes in each stream are separable in time, allowing us to quantify how strongly attention modulates the neural representation of a sound mixture.…”

Auditory Stream Segregation and Selective Attention for Cochlear Implant Listeners: Evidence From Behavioral Measures and Event-Related Potentials

“…Thus, several studies have used recordings of ERPs to investigate the process of object selection and selective attention, tightly related to stream segregation (e.g., Alain and Arnott, 2000 ; Choi et al, 2013 ). Moreover, the amount of attentional modulation of the ERPs has been shown to correlate with the listener’s ability to perform an auditory selective-attention task ( Choi et al, 2014 ; Dai and Shinn-Cunningham, 2016 ; Dai et al, 2018 ), suggesting a strong link to perception. However, to the authors’ knowledge, no previous study has investigated whether selective attention modulates the ERPs in CI listeners and whether such attentional modulation would correlate with performance in an auditory selective-attention task.…”

Cortical and Sensory Causes of Individual Differences in Selective Attention Ability Among Listeners With Normal Hearing Thresholds

“…We find large variability in performance across a range of tasks. More important, depending on the task, variability seems to arise from differences in the ability to control attention, from differences in sensory coding fidelity (which can have an impact on the fidelity of the acoustic cues used for selecting and segregating a target from a sound mixture), or from a combination of both cognitive and sensory factors (e.g., see Dai & Shinn-Cunningham, 2016). Of course, everything from general cognitive ability to aging affects the ability to understand speech in complex settings, often with .…”