Multiple timescales of context shape the perceptual sensitivity to natural pairings of musical pitch and timbre

Musical pitch and timbre (specifically, spectral shape) covary perceptually: lower pitches are associated with darker timbres (less higher-frequency energy) and higher pitches are associated with brighter timbres (more higher-frequency energy). We examined this relationship at multiple timescales of context: trial-level (rates of performance improvement within a testing block), block-level (differences in performance across blocks), session- level (performance as a function of testing block order), and longer-term experience (musical training / background). Musical pitches were labeled as low (C4) or high (G4) from various instruments (trumpet, oboe, trombone, tuba). Testing blocks paired pitch and timbre together to either respect (Consistent) or violate (Reversed) their covariance. All timescales of context contributed to performance, producing clear patterns across experiments. Pitch labeling was poorer in Reversed blocks, but showed steeper rates of improvement than did Consistent blocks (which were often near/at ceiling levels). These patterns were moderated by which condition was tested first in the experiment and by the introduction of trial-by-trial feedback. Greater musical training was consistently correlated with higher accuracy, but adding feedback extinguished this pattern for Consistent blocks. Thus, context on a host of timescales shapes perceptual sensitivity to the natural covariance between musical pitch and timbre.