The multifaceted nature of self-generation effects: Independent and interactive effects of actions, predictability, and delay on sensory processing and memory encoding of sounds.

Actions attenuate responses to self-produced sounds, but the underlying mechanism remains under debate.In fact, factors such as action-sound predictability and enhanced neuromodulation during movement seem to play a role.Meanwhile, the self-generation effects on memoryand their possible interactions with predictabilityremain also largely unexplored.Here, we recorded behavioural, EEG, and pupil responses during a combined self-generation and memory paradigm to assess the effects of self-generation, predictability, and their interactions, as a function of action-sound delay, on the sensory processing and memory of sounds.Predictability was controlled such that self-generated ("motor-auditory"; MA) and externally-generated ("Auditory-only"; A) sounds were equally predictable (or unpredictable) in identity, timing, and probability of occurrence.In each trial, participants memorized predictable or unpredictable MA or A sounds presented with a delay of 150 or 750 ms after the action (MA) or visual cue (A).The same sounds were later tested for recall.Results showed better memory for MA sounds, irrespective of predictability, and larger pupil diameter during actions especially when actions triggered predictable sounds.Self-generation attenuated N1, P2, and Tb responses with short delays, but only in the predictable session.With longer delays, self-generation attenuated N1 (irrespective of predictability), while predictability attenuated P2 and Tb (irrespective of self-generation).Crucially, sensory attenuation correlated with pupil diameter when the effects were strongest (predictable MA sounds presented after short delays).Collectively, we show that actions boost memory and we propose that motor inputs along with neuromodulatory influences shape auditory responses depending on action-stimulus predictability and delay.