Distinct role of central predictive mechanisms in tactile suppression

Abstract

Tactile sensitivity on a limb is reduced during movement, presumably due to central predictive mechanisms that downregulate sensations caused during voluntary action. As suppression also occurs during passive movements, peripheral mechanisms might also contribute, questioning the predictive nature of suppression. Yet, passive movements may not only reflect peripheral but also predictive processes related to non-motor predictions. This study aimed to disentangle central predictive and peripheral feedback mechanisms by having participants detect tactile stimuli on their limb shortly before active and passive movements, which they were informed (cued) or not. We found tactile suppression during both active and passive movements irrespective of whether the movement was cued. Importantly, tactile suppression was larger in active than passive movements highlighting the specific role of central predictive mechanisms.