Pitch and timbre interaction in isolated tones and in sequences

The interaction of pitch and timbre of tones in isolation and in sequences was studied in a series of experiments. Experiment 1 investigated whether pitch, timbre, and duration interact in the detection of changes between tone sequences. It was found that variations in timbre interfered with the detection of pitch changes, as did the variation of pitch when detecting timbre changes. Changing durations did not interfere with detection of either timbre or pitch changes. Experiment 2 investigated whether the interaction between timbre and pitch is a consequence of changes of relations between tones in the sequences. Contextual variation between sequences in pitch interfered with pitch judgments, but no other contextual interference was found. Experiment 3 measured reaction times of various classifications of isolated tones varying in pitch and timbre and found that pitch and timbre interact. These results indicate that pitch and timbre interact at the level of individual tones, they do not interact at a structural level, pitch is coded relationally, and timbre is not coded relationally. [Work supported in part by a Grant-in-Aid of Research from Sigma Xi, The Scientific Research Society.]