Influence of tonal and temporal expectations on chord processing and on completion judgments of chord sequences.

Pitch and time are two principal form-bearing dimensions in Western tonal music. Research on melody perception has shown that listeners develop expectations about "What" note is coming next and "When" in time it will occur. Our study used sequences of chords (i.e., simultaneously sounding notes) to investigate the influence of these expectations on chord processing (Experiments 1 and 4) and subjective judgments of completion (Experiments 2 and 3). Both tasks showed an influence of tonal relations and temporal regularities: expected events occurring at the expected moment were processed faster and led to higher completion judgments. However, pitch and time dimensions interacted only for completion judgments. The present outcome suggests that for chord perception the influence of pitch and time might depend on the required processing: with a more global judgment favoring interactive influences in contrast to a task focusing on local chord processing.