Darshan Shah¹, Zoe Epstein¹, Ziqing Zhang¹, Brianna Charlton¹, Allan Collins¹, Cindy Bukach¹; ¹University of Richmond

Perceptual expertise is associated with holistic processing across many modalities, including faces, cars, and birds, but music reading remains understudied. As a complex perceptual system, music reading can be examined with systems factorial technology, which models holistic processing through contrast manipulations that affect perceptual processing speed. We asked how this contrast manipulation influences holistic processing, indexed by congruency effects (Δ𝑑′ and Δ𝑐). We hypothesized that if experts coactively pool music notes, congruency effects should be similar in high- and low- contrast conditions, as global form should still be salient in low contrast conditions. We had no predictions for conditions in which contrast masked half of the stimuli. Four experts completed three-six sessions in which they responded to sequentially presented composite four-note music sequences with low- or high-contrast on the left and/or right two notes. Hierarchical generalized linear mixed-effects models (binomial probit, with observer-level random effects) estimated congruency effects across contrast levels. Bayesian information criterion favored a model in which contrast moderated congruency effects. On average, discriminability (𝑑′) was significantly higher and response bias (𝑐) was significantly lower in high- than low-contrast conditions. Δ𝑑′ and Δ𝑐 main effects were also observed. As predicted, contrast moderated congruency where congruency effects did not differ for completely high or completely low contrast condition. Interestingly, congruency effects decreased when only part of the stimulus was masked. Overall, contrast manipulations influenced congruency effects suggesting that systems factorial technology may further inform the nature of holistic processing.

Acknowledgements: University of Richmond