Schellenberg and Trehub 1994a,1996a,b).Thus,for example,infants
show better retention of melodic (sequential) intervals of perfect fifths
and fourths (consonant intervals) compared with tritones (dissonant
intervals;Schellenberg and Trehub 1996b),as can be seen in figure 23.3.
They also show superior retention of harmonic (simultaneous) intervals
exemplifying small-integer rather than large-integer ratios (Schellenberg
and Trehub 1996b;Trainor 1997).Moreover,infants and adults tend to
categorize intervals on the basis of consonance or dissonance rather than
size (Schellenberg and Trainor 1996).Accordingly,they more readily
detect a change from a consonant harmonic interval (seven semitones,
or perfect fifth) to a dissonant interval (six semitones,or tritone) than to
another consonant interval (five semitones,or perfect fourth) despite the
greater pitch difference in the latter change (two semitones rather than
one).Even European starlings (Sturnus vulgaris) that are trained
to produce distinctive responses to a specific consonant and dissonant
chord generalize their responses to another consonant and dissonant
chord (Hulse,Bernard,and Braaten 1995).Findings such as these suggest
physiological concomitants of consonance and dissonance.
Infants also exhibit affective and attentional preferences for conso-
nant over dissonant chords and harmonizations of melodies (Crowder,
Reznick,and Rosenkrantz 1991;Zentner and Kagan 1996;Trainor and
Heinmiller 1998),which implies that rudimentary aesthetic judgments
may be partly independent of musical exposure.Overall,data on infants’
processing of simultaneous and sequential tones are in line with the
claims of ancient and medieval scholars and are readily interpretable in
terms of a processing bias for tones related by small-integer ratios.This432 Sandra Trehub
Figure 23.3
Infants’ discrimination (d¢) scores as a function of the frequency ratio of tones in melodic
(sequential) intervals.(From Schellenberg and Trehub 1996b.)Fig.23.3