Enhanced pitch perception in early blind individuals and musicians is due to reduced internal noise

Although it is commonly assumed that early blind individuals have enhanced pitch perception, the literature to date has been contradictory. We measured performance in two tasks known to recruit early vs. late stages of auditory frequency tuning in early blind and sighted individuals with matched levels of musical training. The two groups showed equivalent performance on a tone detection in a notched-noise task that assesses peripheral and subcortical frequency selectivity. In contrast, early blind individuals showed enhanced performance in a pitch discrimination task thought to be mediated by cortical mechanisms. Computational modeling revealed that this enhancement was best explained by reduced internal noise rather than narrower frequency tuning, with both blindness and musical training predicting a reduction in internal noise. These findings identify internal noise as a key factor in experience-driven auditory plasticity as a result of both musical experience and early blindness.