Consciousness and Cognition 87 (2021) 103058 1053-8100/© 2020 Elsevier Inc. All rights reserved. Sensory attenuation of action outcomes of varying amplitude and valence Bartosz Majchrowicz * , Michał Wierzcho´ n Consciousness Lab, Institute of Psychology, Jagiellonian University, Krakow, Poland A R T I C L E INFO Keywords: Sensory attenuation Sensory suppression Sensory amplification Valence perception Preactivation Prediction Sense of agency Volition ABSTRACT Stimuli caused by self-initiated actions are perceived as less intense than those caused externally; this effect is called sensory attenuation (SA). In two experiments, we aimed to assess the impact of the amplitude of outcomes and its affective valence on SA and explicit ratings of sense of agency. This allowed us to test the predictions of the available SA frameworks and better understand the link between SA, affect, and agency. The results indicated that SA can be reversed, and such sensory amplification is driven by low-amplitude and positive-valence outcomes. We also show that intentional action influences the perceived valence of outcomes, and that modulations of explicit sense of agency are divergent from those of SA. Our study shows that valence influences the processing of the amplitude of intentional action outcomes and suggests that none of the currently available frameworks give full justice to SA’s variability. 1. Introduction Self-related stimuli are processed in a specific way and elicit a different set of cognitive and neurophysiological reactions than stimuli with no self-related meaning or value (Northoff et al., 2006). An exemplary manifestation of this is perception of external stimuli. Processing of such stimuli differs between situations in which they are caused by self-initiated volitional actions and when they are caused by external forces that are passively observed by an agent. One dimension which is affected by self-action is the magnitude or amplitude of perceived outcomes. This phenomena is known as sensory attenuation (SA; also referred to as sensory suppression): self-caused events are generally perceived to be weaker as compared to physically identical events that are caused externally (Bla- kemore, Wolpert, & Frith, 1998). The SA effect is observable in both mild (Blakemore, Frith, & Wolpert, 1999) and nociceptive (Wang, Wang, & Luo, 2011) tactile stimulation, as well is in auditory (Weiss, Herwig, & Schütz-Bosbach, 2011) and visual modalities (Cardoso- Leite, Mamassian, Schuttz-Bosbach, & Waszak, 2010). Apart from the perceptual level, SA is also visible on the neurophysiological level: processing of self-caused events has been linked to diminished activation of the anterior cingulate cortex (Blakemore et al., 1998) and attenuated event-related potentials such as auditory N1 (Klaffehn, Baess, Kunde, & Pfister, 2019) and visual N2/P3 (Hughes & Waszak, 2011). Intriguingly, rather than attenuation, some studies also report sensory amplification of self-generated actions (e.g. Reznik, Henkin, Schadel, & Mukamel, 2014; Sim˜ oes-Franklin, Whitaker, & Newell, 2011; discussed below). Due to the fact that SA is observable only in self-initiated actions, it has been has been suggested that the effect is a marker of a feeling of being the author of one’s own actions and their effects (Blakemore et al., 1999; Gentsch & Schütz-Bosbach, 2011), or a sense of agency (SoA) (Haggard, 2017; Moore & Fletcher, 2012). SA can thus be seen as an alternative measure of SoA to the more commonly used intentional binding * Corresponding author at: Institute of Psychology, Jagiellonian University, Ingardena 6, 30-060 Krakow, Poland. E-mail address: majchrowicz.b@gmail.com (B. Majchrowicz). Contents lists available at ScienceDirect Consciousness and Cognition journal homepage: www.elsevier.com/locate/concog https://doi.org/10.1016/j.concog.2020.103058 Received 21 May 2020; Received in revised form 13 November 2020; Accepted 19 November 2020