Auditory attentional selection is biased by reward cues

Abstract

Auditory attention theories suggest that humans are able to decompose the complex acoustic input into separate auditory streams, which then compete for attentional resources. How this attentional competition is influenced by motivational salience of sounds is, however, not well-understood. Here, we investigated whether a positive motivational value associated with sounds could bias the attentional selection in an auditory detection task. Participants went through a reward-learning period, where correct attentional selection of one stimulus (CS+) lead to higher rewards compared to another stimulus (CS-). We assessed the impact of reward-learning by comparing perceptual sensitivity before and after the learning period, when CS+ and CS- were presented as distractors for a different target. Performance decreased after reward-learning when CS+ was a distractor, while it increased when CS- was a distractor. Thus, the findings show that sounds that were associated with high rewards captures attention involuntarily. Additionally, when successful inhibition of a particular sound (CS-) was associated with high rewards then it became easier to ignore it. The current findings have important implications for the understanding of the organizing principles of auditory perception and provide, for the first time, clear behavioral evidence for reward-dependent attentional learning in the auditory domain in humans.

Figure 1

Auditory detection task: (A) Two auditory streams were simultaneously presented on participant’s left and right hand side. Streams were amplitude-modulated tones having distinct frequency and modulation rates. In target trials, the target stream contained a 75 ms-long silence period (right-stream in the figure) that was introduced randomly between 1200 and 1700 ms after the stream onset. Participants were instructed to detect the target stream and indicate its location by pressing a respective button. (B,C) Trials in the pre- and post-reward (B), and reward blocks (C). Trials stared with a 500-ms fixation period that preceded the simultaneous presentation of auditory streams. For their responses participants received visual feedback. In the reward blocks, they could see their total points and how many points they received for each correct answer (1p or 10p).