Vocal laziness by sex: Supplementary figures from Poor neuro-motor tuning of the human larynx: a comparison of sung and whistled pitch imitation

Median imitation inaccuracy is plotted for each stimulus note following the chromatic scale. Singing and whistling are plotted for females in the top panel and for males in the bottom panel. Behaviours are plotted on a common scale to facilitate comparisons (starting from A2, A3 and A5). The grey area encloses the interquartile range. The dotted line indicates a maximally accurate imitation score. Positive scores indicate imitations that were sharp and negative scores indicate imitations that were flat. Solid lines in the top portion of the figure indicate the ranges of participants’ spontaneous singing and whistling pitches. Participant's spontaneous pitches tended to occupy the lower end of the range of the stimulus range for singing and the upper end of the stimulus range for whistling. For both modes of production, accuracy was best for notes within the range of spontaneous pitches. Hence, while participants sung flat on average, they did not consistently transpose melodies downwards. Rather, participants shifted sung notes towards a point within the range of habitually produced pitches. This point may reflect a configuration of least vocal effort, distance from which may make pitch production more effortful. Vocal laziness, or a conservation of vocal effort, may lead singers to compress sung notes towards the pitch associated with a default or preferred configuration of the larynx.