Genetic and Environmental Influences on Singing Self-Evaluation and its Relationship with Singing Ability: An Australian Twin Study

People evaluate their singing ability to varying degrees of accuracy, but why these individual differences occur is largely unknown. Objectively evaluated, everyday singing ability is influenced by both genetic and environmental factors. Since singing self-evaluation (SSE) strongly correlates with everyday singing ability, it is possible that the same factors might influence both. Using a classical twin design, we estimated genetic and environmental influences on SSE and its phenotypic relationship with everyday singing ability in Australian twins (N = 996). Two validated measures of SSE were used: a single self-report item assessing overall singing ability (SSE-Single) and a four-item composite measure (SSE-Factor). Both measures showed significant genetic (SSE-Single A = 42%; SSE-Factor A = 53%) and unshared environmental influences (both E = 29%). Phenotypic correlations between the SSE measures and everyday singing ability ranged from r_p = 0.67 - 0.68 and were significantly influenced by genetic, shared and unshared environmental factors (SSE-Single A = 41%, C = 51%, E = 8%; SSE-Factor A = 37%, C = 52%, E = 11%). Strong genetic correlations (r_g = 0.63 - 0.64) were observed between SSE measures and everyday singing ability, as well as between both SSE measures (r_g = 0.82), suggesting shared underlying genes. Taken together, our findings indicate that both genes and environments affect how individuals evaluate their own singing ability and how accurate these evaluations are compared to their actual ability.