Articulation correction of the deaf by means of visually displayed acoustic information

Contains fulltext : mmubn000001_070224463.pdf (publisher's version ) (Open Access)Promotor : W. Levelt94 pProefschrift Katholieke Universiteit Nijmege

Measures of temporal pattern complexity

In this study, three measures of temporal pattern complexity were compared as regards their perceptual validity. The first measure, based on the work of Tanguiane (1993), uses the idea that a temporal pattern can be described in terms of (elaborations of) more simple patterns, simultaneously at different levels. The second measure is based on the complexity measure for finite sequences proposed by Lempel and Ziv (1976), which is related to the number of steps in a self-delimiting production process by which such a sequence is presumed to be generated. The third measure, newly developed here, is rooted in the theoretical framework of rhythm perception of Povel and Essens (1985). It takes into account the ease of coding a temporal pattern and the complexity of the segments resulting from this coding. The perceptual validity of the three measures was evaluated in an experiment in which subjects judged the complexity of 35 temporal patterns. Correlations between the three measures and complexity judgments indicated that the proposed measure is a meaningful measure of temporal pattern complexity in that it exhibited a significantly higher correlation than the other two measures. This was expected due to the fact that this measure, unlike the other two, is based on an empirically tested model of rhythm perception that takes into account the isochronous frame against which the rhythm is perceived. Reasons for the differences in performance between the three measures are discussed

Harmonic factors in the perception of tonal melodies

Item does not contain fulltextBy common assumption, the first step in processing a tonal melody consists in setting up the appropriate metrical and harmonic frames required for the mental representation of the sequence of tones. Focusing on the generation of a harmonic frame, this study aims (a) to discover the factors that facilitate or interfere with the development of a harmonic interpretation, and (b) to test the hypothesis that goodness ratings of tone sequences largely depend on whether the listener succeeds in creating a suitable harmonic interpretation. In two experiments, listeners rated the melodic goodness of selected sequences of 10 and 13 tones and indicated which individual tones seemed not to fit. Results indicate that goodness ratings (a) are higher the more common the induced harmonic progression, (b) are strongly affected by the occurrence and position of nonchord tones: sequences without nonchord tones were rated highest, sequences with anchoring nonchord tones intermediately, and nonanchoring nonchord tones lowest. The explanation offered is compared with predictions derived from other theories, which leads to the conclusion that when a tone sequence is perceived as a melody, it is represented in terms of its underlying harmony, in which exact pitch-height characteristics play a minor role

Towards an on-line model of music perception

Item does not contain fulltextThe goal of this study is to develop a computational model, based on a set of assumptions, that captures the on-line processing of music. The model construes music perception in terms of 1) the activation of pertinent musical knowledge stored in the listener's long term memory, and 2) the application of perceptual mechanisms that organize the elements in the input into a coherent mental representation. The viability of the model is investigated in experiments that examine how perception evolves while the stimulus is presented incrementally, by studying goodness judgments and the expectations that arise in the process. The model we are developing mainly pertains to the stage in which the elements in the input is transformed into a mental representation

Perception of arpeggiated chord progressions

The nature of the representation that listeners form of the underlying harmony of a tone sequence was investigated in 4 experiments. Stimuli were tone sequences consisting of consecutive groups of three tones each forming an arpeggiated triad. In Experiments 1 and 2, listeners rated the musical logic of 6-tone sequences with different triad combinations. It was found that ratings were affected by the usualness of the chord successions. To investigate whether longer sequences of chord changes are incorporated in the mental representation, in Experiment 3 listeners rated 9-tone sequences implying 2 successive chord changes. Both chord changes affected the ratings, the second chord change having a stronger influence than the first. Experiment 4 investigated how the progression representation develops over time, by presenting 15-tone sequences as increasing initial fragments of 9, 12, and 15 tones. For each fragment listeners 1) rated its musical logic, 2) searched the first tone of an imagined continuation, and 3) indicated whether that tone was a suitable ending tone. The ratings confirmed the earlier results, and furthermore the continuation tones appeared to be members of the expected chord. The findings support the hypothesis that listeners included the underlying harmonic structure in their representation of a tone sequence

The processing of chords in tonal melodic sequences

A model is proposed for the On-Line Harmonic Processing (OLHP) of tonal melodic sequences in which each incoming tone is described in terms of its features Fittingness, compliance with the previous harmony, Uncertainty, ambiguity of a new harmony and, Chord Change, goodness of the connection between previous and new harmony. To test this model in Experiment 1 listeners rated the musical logic of 10-tone sequences presented with an induced segmentation in groups of 3-3-3-1, and following an harmonic progression of I-target-V-I, respectively, with the harmonic functions I, II, III, IV, V, or VI inserted as target fragment. The results support the Chord Change feature of the model. In Experiment 2 these sequences were rated as tone-by-tone increasing fragments, starting from the initial 3 tones up to the complete sequence. The ratings of the incremental sequences supported the findings of the first experiment. The three features in the model explained 46.4 % of the variance in the target ratings, although Uncertainty seemed to have no effect. In a comparison with two other models OLHP model performed best. Finally, an a-posteriori model consisting of Chord Change and a variable quantifying pitch proximity between consecutive tones accounted for a major part of the variance. It is concluded that listeners employ OLHP's features in their representation of the sequences and that both harmony and pitch height are indispensable factors in a model of melody perception

Complexity Measures of Musical Rhythms

The study of the factors that determine the complexity of rhythms has theoretical as well as practical relevance. On the theoretical side, a successful measure of complexity will shed light on the encoding and memory processes involved in rhythm perception. Hence, it will be able to indicate whether a given rhythm will be easy or difficult to memorize and reproduce. On the practical side, such a measure will complement current research in rhythm similarity and music pattern recognition in general. In this paper, three measures of complexity of musical rhythms are compared. The first mea-sure is based on the work of Tanguiane (1993), and uses the idea that a rhythmic pattern can be described in terms of (elaborations of) more simple patterns, simultaneously at different levels. The second measure is based on the complexity measure for finite sequences proposed by Lempel and Ziv (1976), which is related to the number of steps in a self-delimiting pro-duction process by which such a sequence is presumed to be generated. The third measure is rooted in the theoretical framework of rhythm perception discussed in Povel and Essens (1985). The predictive strength of the three measures has been evaluated in an experiment in which listeners judged the complexity of a set of selected rhythms on a 5-point scale. Results of the experiment will be reported and the strengths and weaknesses of the complexity measures as well as their relationship to current work in rhythm similarity will be discussed

Perceptual Issues in Music Pattern Recognition: Complexity of Rhythm and Key Finding

We consider several perceptual issues in the context of machine recognition of music patterns. It is argued that a successful implementation of a music recognition system must incorporate perceptual information and error criteria. We discuss several measures of rhythm complexity which are used for determining relative weights of pitch and rhythm errors. Then, a new method for determining a localized tonal context is proposed. This method is based on empirically derived key distances. The generated key assignments are then used to construct the perceptual pitch error criterion which is based on note relatedness ratings obtained from experiments with human listeners

Towards an on-line model of music perception

The goal of this study is to develop a computational model, based on a set of assumptions, that captures the on-line processing of music. The model construes music perception in terms of 1) the activation of pertinent musical knowledge stored in the listener's long term memory, and 2) the application of perceptual mechanisms that organize the elements in the input into a coherent mental representation. The viability of the model is investigated in experiments that examine how perception evolves while the stimulus is presented incrementally, by studying goodness judgments and the expectations that arise in the process. The model we are developing mainly pertains to the stage in which the elements in the input is transformed into a mental representation