The Brain's Sensitivity to Sensory Error Can Be Modulated by Altering Perceived Variability.

When individuals make a movement that produces an unexpected outcome, they learn from the resulting error. This process, essential in both acquiring new motor skills and adapting to changing environments, critically relies on error sensitivity, which governs how much behavioral change results from a given error. Although behavioral and computational evidence suggests error sensitivity can change in response to task demands, neural evidence regarding the flexibility of error sensitivity in the human brain is lacking. Here, we tested whether the nervous system's sensitivity to errors, as measured by prediction-driven suppression of auditory cortical activity, can be modulated by altering participants' (both males and females) perceived variability during speech. Our results showed that error sensitivity, as measured by this suppression, was increased after exposure to an auditory perturbation that increased speakers' perceived variability. The current study establishes the validity of behaviorally modulating the nervous system's sensitivity to errors, which has significant potential to enhance motor learning and rehabilitation.