Automatic responses to musical intervals: Contrasts in acoustic roughness predict affective priming in Western listeners.

The aim of the present study is to determine which acoustic components of harmonic consonance and dissonance influence automatic responses in a simple cognitive task. In a series of affective priming experiments, eight pairs of musical intervals were used to measure the influence of acoustic roughness and harmonicity on response times in a word-classification task conducted online. Interval pairs that contrasted in roughness induced a greater degree of affective priming than pairs that did not contrast in terms of their roughness. Contrasts in harmonicity did not induce affective priming. A follow-up experiment used detuned intervals to create higher levels of roughness contrasts. However, the detuning did not lead to any further increase in the size of the priming effect. More detailed analysis suggests that the presence of priming in intervals is binary: in the negative primes that create congruency effects the intervals' fundamentals and overtones coincide within the same equivalent rectangular bandwidth (i.e., the minor and major seconds). Intervals that fall outside this equivalent rectangular bandwidth do not elicit priming effects, regardless of their dissonance or negative affect. The results are discussed in the context of recent developments in consonance/dissonance research and vocal similarity.