A right visual field advantage without left hemisphere lateralization in music notation reading

Abstract

The divided visual field (VF) paradigm has been commonly used to examine hemispheric lateralization in the recognition of visual stimuli, i.e., a right visual field (RVF) advantage indicates left hemisphere (LH) lateralization. For example, in English word recognition, an RVF advantage has been observed in tachistoscopic recognition tasks, consistent with the fMRI finding that a region in the LH selectively responds to words in contrast to random letter strings. Recent research suggests that in addition to hemispheric lateralization, the RVF advantage may also be due to information structure of the words and reading direction (Brysbaert & Nazir, 2005). However, it is difficult to tease apart the contribution of the three factors in English word recognition. Here, we tested whether reading direction alone is sufficient to account for the RVF advantage with music reading. While music reading shares the left-to-right reading direction with English reading, music sequences are highly varied and presumably do not have an asymmetric information structure as English words. Also, experts learn to recruit both hemispheres for music reading (Wong & Gauthier, 2010), in contrast to the LH lateralization of word recognition. Music-reading experts and novices judged whether two sequentially presented three-note sequences were identical with key press. The first sequence was presented in the far-right, near-right, center, near-left or far-left part of the VF, while the central fixation of participants was monitored by eye-tracking. Experts but not novices showed a performance advantage when the sequence was presented in the RVF compared with the left VF locations. Also, faster music readers (measured by a separate perceptual fluency test) predicted a larger RVF advantage, suggesting that music-reading training results in the RVF advantage. Our results suggest that an RVF advantage does not always imply LH lateralization; reading direction alone is sufficient to account for the RVF advantage in reading.