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JNMR005M03 Chord processing in melodic sequences


Fig. 3. Experiment 1: Stimulus construction: Factorial design of the target fragments that are inserted in the context sequence of Figure 2. Across rows the three contour categories are indicated (top 2 rows = contour category 1; middle 2 rows = contour category 2; lower 2 rows = contour category 3); across columns the six implied chord functions within the context are indicated.

The stimuli were presented in a random order for each respondent. From trial to trial sequences were presented at a pitch height quasi-randomly selected from a range of 6 semitones around C4, such that consecutive trials were never in the same key. Respondents practiced with 12 training trials that were similar to the experimental stimuli, but which did not appear in the experiment proper. They were told that the range of goodness in the experimental sequences was approximately the same as in the training stimuli, and were encouraged to use the whole rating scale. 2.2 Results and discussion

Fig. 4. Experiment 1: Predictions for the progression categories. For each Condition the tones in the Target fragment, the resulting Progression and the summed Usualness of the individual chord changes is shown. The usualness of an individual chord change is determined by its indexation in terms of Table 1, in which a first category chord change receives a penalty of 1, a second category chord change a penalty of 2, a third category chord change a penalty of 3 and a fourth category chord change a penalty of 4.

In general, listeners found the task rather difficult, because they found differences between sequences small, but all of them were able to complete the experiment. The individual responses of each of the 20 listeners were correlated with the responses of the other 19 participants. The average of these correlations ranged between 0.23 and 0.39; the overall mean correlation between listeners’ responses was 0.32. Cronbach’s alpha of the responses was 0.90, indicating high agreement among listeners. The mean ratings for the 6 Progression conditions are shown in Figure 5A. Target chord I was rated highest, closely followed from high to low by V, IV, II, and at some distance


Abstract JNMR005M03 Nijmegen Institute for Cognition and Information, Nijmegen, The Netherlands Erik Jansen and Dirk-Jan Povel Accepted: 24...