Self-generation and sound intensity interactively modulate perceptual bias, but not perceptual sensitivity

Abstract

The ability to distinguish self-generated stimuli from those caused by external sources is critical for all behaving organisms. Although many studies point to a sensory attenuation of self-generated stimuli, recent evidence suggests that motor actions can result in either attenuated or enhanced perceptual processing depending on the environmental context (i.e., stimulus intensity). The present study employed 2-AFC sound detection and loudness discrimination tasks to test whether sound source (self- or externally-generated) and stimulus intensity (supra- or near-threshold) interactively modulate detection ability and loudness perception. Self-generation did not affect detection and discrimination sensitivity (i.e., detection thresholds and Just Noticeable Difference, respectively). However, in the discrimination task, we observed a significant interaction between self-generation and intensity on perceptual bias (i.e. Point of Subjective Equality). Supra-threshold self-generated sounds were perceived softer than externally-generated ones, while at near-threshold intensities self-generated sounds were perceived louder than externally-generated ones. Our findings provide empirical support to recent theories on how predictions and signal intensity modulate perceptual processing, pointing to interactive effects of intensity and self-generation that seem to be driven by a biased estimate of perceived loudness, rather by changes in detection and discrimination sensitivity.

Self-Initiation Enhances Perceptual Processing of Auditory Stimuli in an Online Experiment

“…Consequently, perceptual bene ts of actively generated stimuli might be overestimated, if the stimulus order is not counterbalanced (Myers et al, 2020). However, preceding studies using a similar experimental setup show results compatible with our ndings (Reznik et al, 2015;Paraskevoudi & SanMiguel, 2021). Further, combining active and passive trials, the results of our study did not imply a general response bias towards the rst tone (Figure S3).…”

“…Note that our results show relatively small differences between proportions of responses in which participants judged the loudness of the test stimuli as higher than the loudness of the standard. Comparing the results of our online experiment with other studies including a similar experimental set-up, but that were conducted in a laboratory environment (Reznik et al, 2015;Paraskevoudi & SanMiguel, 2021), we found relatively small deviations from perceived equality of loudness judgements (mean ± standard error of the mean: active: 53.0 ± 1.2%, passive: 48.9 ± 1%; Reznik et al (2015): active: 61.4 ± 2.1%, passive: 56.2 ± 2.1%; Paraskevoudi & SanMiguel (2021): active: 46.1 ± 3.9%, passive: 53.6 ± 3.7%). This might be due to the lack of control over the noise of the participant's environment, and the di culty to determine the exact stimulus intensity due to individual differences in technical set-ups.…”

Cancelling cancellation? Sensorimotor control, agency, and prediction

“…However, while predictive cancellation has seemed foundational to successful theories of action control and awareness, research in recent years has begun to undermine the idea that predicted action outcomes really are cancelled. An emerging body of work has begun to show thatcontrary to classic ideasexpected action outcomes may be perceptually and neurally enhanced Dogge, Custers, Gayet, et al, 2019;Guo & Song, 2019;Paraskevoudi & SanMiguel, 2021;Reznik et al, 2014Reznik et al, , 2021Reznik & Mukamel, 2019;Thomas et al, 2022;Yon et al, 2018Yon et al, , 2021Yon et al, , 2022; see also Hudson et al, 2015Hudson et al, , 2018. These findings accord with a general picture of perceptual prediction described by Bayesian models which stress that it is adaptive for agents to bias their perceptual inferences towards what they expect, perhaps via increasing the gain on expected sensory channels (Bar, 2004;Yuille & Kersten, 2006;Press et al, 2020a).…”

Active self-motion control and the role of agency under ambiguity

“…It should be noted that previous studies using the same type of discrimination task observed different effects of the active condition on these two parameters Paraskevoudi and SanMiguel, 2021). For example, Paraskevoudi and SanMiguel (2021) found reduced perceived intensity (i.e., perceptual bias) for self-generated sounds when presented at supra-threshold intensities (high level), but which increased when presented at near-threshold intensities (low level).…”