Long-term musical training modulates the body model

Despite constantly performing actions with their hands, healthy individuals display distorted hand representations. These distortions have been found in a body representation called 'the body model', which plays a fundamental role in position sense. There is a growing number of studies showing that changes in this representation may optimize performance in certain skills (e.g., magicians, baseball players). This has led to the hypothesis that the distortions may facilitate our actions. One highly trained group of individuals that rely on an accurate position sense about the fingers, are piano players. However, musicians have yet to be studied in the body model task. Therefore, we recruited a group of expert piano players (average practice time 12.85 h/week, average years playing 16.22 ± 3.6) and an age- and sex-matched control group. We hypothesized that piano players would have more accurate hand representation, as precise finger location knowledge is essential for skilled piano performance. Our results showed that piano players were significantly more accurate at estimating hand width compared to the controls; in fact, their estimates of this measure were not different than their physical size. This supports our hypothesis and suggests that the need for more accurate localization of the fingertips when playing may result in a more accurate estimate of hand width in the body model task. There was, however, no difference between the groups for finger length, as both piano and control groups significantly underestimated this measure. This result may reflect the typical position of the hands while playing piano, as the fingers are kept curved to aid proper technique. Taken together, our results support the hypothesis that distortions may in fact facilitate our actions.