hide
Free keywords:
Music; Sound; Language
Abstract:
Only little systematic research has examined event-related
brain potentials (ERPs) elicited by the cognitive processing of
music. The present study investigated how music processing is
influenced by a preceding musical context, affected by the task
relevance of unexpected chords, and influenced by the degree
and the probability of violation. Four experiments were
conducted in which ``nonmusicians'' listened to chord
sequences, which infrequently contained a chord violating
the sound expectancy of listeners. Integration of in-key chords
into the musical context was reflected as a late negative-frontal
deflection in the ERPs. This negative deflection declined
towards the end of a chord sequence, reflecting normal
buildup of musical context. Brain waves elicited by chords with
unexpected notes revealed two ERP effects: an early right-
hemispheric preponderant-anterior negativity, which was
taken to reflect the violation of sound expectancy; and a late
bilateral-frontal negativity. The late negativity was larger
compared to in-key chords and taken to reflect the higher
degree of integration needed for unexpected chords. The early
right-anterior negativity (ERAN) was unaffected by the task
relevance of unexpected chords. The amplitudes of both early
and late negativities were found to be sensitive to the degree
of musical expectancy induced by the preceding harmonic
context, and to the probability for deviant acoustic events. The
employed experimental design opens a new field for the
investigation of music processing. Results strengthen the
hypothesis of an implicit musical ability of the human
brain.
