Iconic recognition of musical symbols in the lateral visual fields.

Subjects with formal musical training were tested tachistoscopically in order to obtain thresholds for recognizing single notes a staff, presented successively to the lateral visual fields. They were also tested on backward visual making of the same stimuli to determine the interstimllus interval needed to escape the masking effect (critical ISI). Response requirements in threshold and ISI conditions were nonverbal (depressing an organ key), or verbal (indicating the stimulus by name). Recognition threshold for notes were lower in the right visual field than in the left, and verbal responses were easier than manual responses in the threshold condition. However, critical ISIs were lower in the left field than in the right, and ISIs from the left visual field were lower with manual responses than with verbal responses. These findings support the idea that (a) threshold and ISI represent separate levels of perceptual processing, and (b) in trained subjects, the ability to recognize musical symbols may be governed by the left hemisphere, while the information-processing stage of iconic storage may occur in the right hemisphere.