Reconcile sensory attenuation and enhancement: The temporal dynamics of self-generated sensory feedback

Self-generated touches are often perceived as weaker than externally generated ones, a phenomenon known as sensory attenuation. However, recent studies have challenged this view by providing evidences that actions could also enhance predicted touch. To investigate this paradox, we examined the temporal dynamics of perceptual processing using steady-state somatosensory evoked potentials (SSSEP) and sliding time window analysis. Results showed that SSSEP in the very early window was smaller in the no-delay and active conditions compared to the delayed and passive condition, respectively, consistent with sensory attenuation. However, this attenuation soon disappeared and reversed in the later windows and onward, indicating an early attenuation followed by a later enhancement. This study resolves the paradox of sensory attenuation and enhancement in self-generated sensory signals by demonstrating that these processes occur at different phases of sensory processing. The findings reveal a sophisticated dynamic balance in sensory processing, facilitating optimal interaction with the environment.