Hemispheric asymmetries in setticlavio reading

Musical setticlavio (literally, seven clefs) reading refers to the ability to read (i.e., to say aloud, without to sing) the musical note labels in the 7 musical clefs. The present research report aims to investigate hemispheric asymmetries in such a basic musical ability, very poorly investigated in the domain of cognitive neurosciences. Sixty-three musicians underwent lateralized tachistoscopic presentation of musical notes on staves, 50% in the left and 50% in the right visual field, associated with each of the 7 musical clefs. The subjects' task was to pronounce as fast as possible the name of the presented note, taking into account the current clef symbol. Mixed directions of asymmetry with different involvements of the left and right hemisphere in each clef were observed. Whereas reading in the treble, bass, alto, tenor, and mezzosoprano clef showed no lateral asymmetries, a left hemisphere asymmetry was observed with the soprano clef and a right hemisphere asymmetry with the baritone clef. This effect was observed with accuracy but not with reaction time. These results suggest that there is not a univocal hemispheric balance in musical setticlavio reading, reflecting several possible underlying reading mechanisms. Moreover, inversely proportional results between performance (both accuracy and reaction time) and distance from the reference clef (treble) suggest that setticlavio reading is based on a spatial rather than verbal code.