A bidimensional model of pitch in the recognition of melodies

Pitch can be conceptualized as a bidimensional quantity, reflecting both the overall pitch level of a tone (tone height) and its position in the octave (tone chroma). Though such a conceptualization has been well supported for perception of a single tone, it has been argued that the dimension of tone chroma is irrelevant in melodic perception. In the current study, melodies were subjected to structural transformations designed to evaluate the effects of interval magnitude, contour, tone height, and tone chroma. In two transformations, the component tones of a melody were displaced by octave intervals, either preserving or violating the pattern of changes in pitch direction (melodic contour). Replicating previous work, when contour was violated perception of the melody was severely disrupted. In contrast, when contour was preserved the melodies were identified as accurately as the untransformed melodies. In other transformations, a variety of forms of contour information were preserved, while eliminating information for absolute pitch and interval magnitude. The level of performance on all such transformations fell between the levels observed in the other two conditions. These results suggest that the bidimensional model of pitch is applicable to recognition of melodies as well as single tones. Moreover, the results argue that contour, as well as interval magnitude, is providing essential information for melodic perception.     

Recognition of melodic transformations: Inversion,retrograde, and retrograde inversion

The melodic transformations of inversion, retrograde, and retrograde inversion occur in pieces of music. An important question is whether such manipulations of melodic material are perceptually accessible to the listener. This study used a short-term recognition-memory paradigm and found that in the easier conditions all these transformations were recognized with better than chance accuracy. The ascending order of difficulty was: inversion, retrograde, retrograde inversion. There was no evidence that listeners distinguish between transforms that preserve the exact interval relationships of the standard stimulus and those that merely preserve its contour (pattern of ups and downs). In view of the order of difficulty of the transforms, two theoretical explanations of performance are possible (1) Listeners may perform the mental transformation required by the recognition task on a representation of the vector of pitches in the standard—an operation that is very like transforming a mental image of the written notation. (2) Listeners may handle inversions differently from the other transformations, comparing the standard and the comparison contour element by contour element, in temporal order. In this view, the temporal dimension would appear to have precedence over the pitch dimension in the musical structure, in consideration of the consequences of disturbing it.     

Recognition of music in long-term memory: Are melodic and temporal patterns equal partners?

The notion that the melody (i.e., pitch structure) of familiar music is more recognizable than its accompanying rhythm (i.e., temporal structure) was examined with the same set of nameable musical excerpts in three experiments. In Experiment 1, the excerpts were modified so as to keep either their original pitch variations, whereas durations were set to isochrony (melodic condition) or their original temporal pattern while played on a single constant pitch (rhythmic condition). The subjects, who were selected without regard to musical training, were found to name more tunes and to rate their feeling of knowing the musical excerpts far higher in the melodic condition than in the rhythmic condition. These results were replicated in Experiment 2, wherein the melodic and rhythmic patterns of the musical excerpts were interchanged to create chimeric mismatched tunes. The difference in saliency of the melodic pattern and the rhythmic pattern also emerged with a music-title-verification task in Experiment 3, hence discarding response selection as the main source of the discrepancy. The lesser effectiveness of rhythmic structure appears to be related to its lesser encoding distinctiveness relative to melodic structure. In general, rhythm was found to be a poor cue for the musical representations that are stored in long-term memory. Nevertheless, in all three experiments, the most effective cue for music identification involved the proper combination of pitches and durations. Therefore, the optimal code of access to long-term memory for music resides in a combination of rhythm and melody, of which the latter would be the most informative.     

Representation and execution of vocal motor programs for expert singing of tonal melodies

Three experiments were conducted to study motor programs used by expert singers to produce short tonal melodies. Each experiment involved a response-priming procedure in which singers prepared to sing a primary melody but on 50% of trials had to switch and sing a different (secondary) melody instead. In Experiment 1, secondary melodies in the same key as the primary melody were easier to produce than secondary melodies in a different key. Experiment 2 showed that it was the initial note rather than key per se that affected production of secondary melodies. In Experiment 3, secondary melodies involving exact transpositions were easier to sing than secondary melodies with a different contour than the primary melody. Also, switches between the keys of C and G were easier than those between C and E. Taken together, these results suggest that the initial note of a melody may be the most important element in the motor program, that key is represented in a hierarchical form, and that melodic contour is represented as a series of exact semitone offsets.     

Rhythm and Melody in Children and Adolescents after Left or Right Temporal Lobectomy

Rhythm (a pattern of onset times and duration of sounds) and melody (a pattern of sound pitches) were studied in 22 children and adolescents several years after temporal lobectomy for intractable epilepsy. Left and right lobectomy groups discriminated rhythms equally well, but the right lobectomy group was poorer at discriminating melodies. Children and adolescents with right lobectomy, but not those with left temporal lobectomy, had higher melody scores with increasing age. Rhythm but not melody was related to memory for the right lobectomy group. In neither group was melody related to age at onset of non-febrile seizures, time from surgery to music tests, or the linear amount of temporal lobe resection. Pitch and melodic contour show different patterns of lateralization after temporal lobectomy in childhood or adolescence.     

The role of familiarity in episodic memory and metamemory for music

Participants heard music snippets of varying melodic and instrumental familiarity paired with animal-name titles. They then recalled the target when given either the melody or the title as a cue, or they gave name feeling-of-knowing (FOK) ratings. In general, recall for titles was better than it was for melodies, and recall was enhanced with increasing melodic familiarity of both the cues and the targets. Accuracy of FOK ratings, but not magnitude, also increased with increasing familiarity. Although similar ratings were given after melody and title cues, accuracy was better with title cues. Finally, knowledge of the real titles of the familiar music enhanced recall but had, by and large, no effect on the FOK ratings.     

Children's perception of certain musical properties: scale and contour

Children's perception of scale and contour in melodies was investigated in five studies. Experimental tasks included judging transposed renditions of melodies (Studies 1 and 3), discriminating between transposed renditions of a melody (Study 2), judging contour-preserving transformations of melodies (Study 4), and judging similarity to a familiar target melody of transformations preserving rhythm or rhythm and contour (Study 5). The first and second studies showed that young children detect key transposition changes even in familiar melodies and they perceive similarity over key transpositions even in unfamiliar melodies. Young children also are sensitive to melodic contour over transformations that preserve it (Study 5), yet they distinguish spontaneously between melodies with the same contour and different intervals (Study 4). The key distance effect reported in the literature did not occur in the tasks of this investigation (Studies 1 and 3), and it may be apparent only for melodies shorter or more impoverished than those used here.     

The generation of temporal and melodic expectancies during musical listening

When listening to a melody, we are often able to anticipate not onlywhat tonal intervals will occur next but alsowhen in time these will appear. The experiments reported here were carried out to investigate what types of structural relations support the generation of temporal expectancies in the context of a melody recognition task. The strategy was to present subjects with a set of folk tunes in which temporal accents (i.e., notes with a prolonged duration) always occurred in the first half of a melody, so that expectancies, if generated, could carry over to an isochronous sequence of notes in the latter half ofthe melody. The ability to detect deviant pitch changes in the final variation as a function of rhythmic context was then evaluated. Accuracy and reaction time data from Experiment 1 indicated that expectancy formation jointly depends on an invariant periodicity of temporal accentuation and the attentional highlighting ofcertain melodic relations (i.e., phrase ending points). In Experiment 2, once these joint expectancies were generated, the temporal dimension had a greater facilitating effectupon melody recognition than did the melodic one. These results are discussed in terms of their implications for the perceptual processing of musical events.     

The role of melodic and temporal cues in perceiving musical meter

A number of different cues allow listeners to perceive musical meter. Three experiments examined effects of melodic and temporal accents on perceived meter in excerpts from folk songs scored in 6/8 or 3/4 meter. Participants matched excerpts with 1 of 2 metrical drum accompaniments. Melodic accents included contour change, melodic leaps, registral extreme, melodic repetition, and harmonic rhythm. Two experiments with isochronous melodies showed that contour change and melodic repetition predicted judgments. For longer melodies in the 2nd experiment, variables predicted judgments best at the beginning of excerpts. The final experiment, with rhythmically varied melodies, showed that temporal accents, tempo, and contour change were the strongest predictors of meter. The authors' findings suggest that listeners combine multiple melodic and temporal features to perceive musical meter.     

Controlled attending as a function of melodic and temporal context

Melodic and rhythmic context were systematically varied in a pattern recognition task involving pairs (standard-comparison) of nine-tone auditory sequences. The experiment was designed to test the hypothesis that rhythmic context can direct attention toward or away from tones which instantiate higher order melodic rules. Three levels of melodic structure (one, two, no higher order rules) were crossed with four levels of rhythm [isochronous, dactyl (A U U), anapest (U U A), irregular]. Rhythms were designed to shift accent locations on three centrally embedded tones. Listeners were more accurate in detecting violations of higher order melodic rules when the rhythmic context induced accents on tones which instantiated these rules. Effects are discussed in terms of attentional rhythmicity.     

A probabilistic model of melody perception

This study presents a probabilistic model of melody perception, which infers the key of a melody and also judges the probability of the melody itself. The model uses Bayesian reasoning: For any "surface" pattern and underlying "structure," we can infer the structure maximizing P (structure|surface) based on knowledge of P (surface, structure). The probability of the surface can then be calculated as ∑ P (surface, structure), summed over all structures. In this case, the surface is a pattern of notes; the structure is a key. A generative model is proposed, based on three principles: (a) melodies tend to remain within a narrow pitch range; (b) note-to-note intervals within a melody tend to be small; and (c) notes tend to conform to a distribution (or key profile) that depends on the key. The model is tested in three ways. First, it is tested on its ability to identify the keys of a set of folksong melodies. Second, it is tested on a melodic expectation task in which it must judge the probability of different notes occurring given a prior context; these judgments are compared with perception data from a melodic expectation experiment. Finally, the model is tested on its ability to detect incorrect notes in melodies by assigning them lower probabilities than the original versions.     

Dynamic melody recognition: Distinctiveness and the role of musical expertise

The hypothesis that melodies are recognized at moments when they exhibit a distinctive musical pattern was tested. In a melody recognition experiment, point-of-recognition (POR) data were gathered from 32 listeners (16 musicians and 16 nonmusicians) judging 120 melodies. A series of models of melody recognition were developed, resulting from a stepwise multiple regression of two classes of information relating to melodic familiarity and melodic distinctiveness. Melodic distinctiveness measures were assembled through statistical analyses of over 15,000 Western themes and melodies. A significant model, explaining 85% of the variance, entered measures primarily of timing distinctiveness and pitch distinctiveness, but excluding familiarity, as predictors of POR. Differences between nonmusician and musician models suggest a processing shift from momentary to accumulated information with increased exposure to music. Supplemental materials for this article may be downloaded from http://mc.psychonomic-journals.org/content/supplemental.     

The perception of melodies distorted by splitting into several octaves: Effects of increasing proximity and melodic contour

Splitting up the familiar tune “Yankee Doodle” by placing successive notes in different octaves makes it very difficult to recognize. The present experiments generalize this finding to more than one familiar tune and to presentation by actual musical instruments. Tunes differ in the degree to which their recognizability is affected by scrambling into different octaves, but recognition of all 10 tunes investigated was substantially diminished by the distortion. Increasing pitch proximity of temporally adjacent notes by leaving pairs or triples of successive notes intact within the same octave increases recognizability of at least some scrambled tunes. Leaving the melodic contour (the pattern of ups and downs) intact while splitting up the melody increases recognizability for subjects informed of the preservation of contour, though recognition is still worse than for undistorted versions.     

Harmonic,melodic, and frequency height influences in the perception of multivoiced music

Two experiments addressed the influences of harmonic relations, melody location, and relative frequency height on the perceptual organization of multivoiced music. In Experiment 1, listeners detected pitch changes in multivoiced piano music. Harmonically related pitch changes and those in the middle-frequency range were least noticeable. All pitch changes were noticeable in the high-frequency voice containing the melody (the most important voice), suggesting that melody can dominate harmonic relations. However, the presence of upper partials in the piano timbre used may have accounted for the harmonic effects. Experiment 2 employed pure sine tones, and replicated the effects of Experiment 1. In addition, the influence of the high-frequency melody on the noticeability of harmonically related pitches was lessened by the presence of a second melody. These findings suggest that harmonic, melodic, and relative frequency height relationships among voices interact in the perceptual organization of multivoiced music.     

Schema-based processing in auditory scene analysis

What is the involvement of what we know in what we perceive? In this article, the contribution of melodic schema-based processes to the perceptual organization of tone sequences is examined. Two unfamiliar six-tone melodies, one of which was interleaved with distractor tones, were presented successively to listeners who were required to decide whether the melodies were identical or different. In one condition, the comparison melody was presented after the mixed sequence: a target melody interleaved with distractor tones. In another condition, it was presented beforehand, so that the listeners had precise knowledge about the melody to be extracted from the mixture. In the latter condition, recognition performance was better and a bias toward same responses was reduced, as compared with the former condition. A third condition, in which the comparison melody presented beforehand was transposed up in frequency, revealed that whereas the performance improvement was explained in part by absolute pitch or frequency priming, relative pitch representation (interval and/or contour structure) may also have played a role. Differences in performance as a function of mean frequency separation between target and distractor sequences, when listeners did or did not have prior knowledge about the target melody, argue for a functional distinction between primitive and schema-based processes in auditory scene analysis.     

Independent temporal and pitch structures in determination of musical phrases

In two experiments we addressed the roles of temporal and pitch structures in judgments of melodic phrases. Musical excerpts were rated on how good or complete a phrase they made. In Experiment 1, trials in the temporal condition retained the original temporal pattern but were equitonal; trials in the pitch condition retained the original pitch pattern but were equitemporal; and trials in the melody condition contained both temporal and pitch patterns. In Experiment 2, one pattern (pitch or temporal) was shifted in phase and recombined with the other pattern to create the pitch and temporal conditions. In the melody condition, both patterns were shifted together. In both experiments, ratings in the temporal and pitch conditions were uncorrelated, and the melody condition ratings were accurately predicted by a linear combination of the pitch and temporal condition ratings. These results were consistent across musicians with varying levels of experience.     

The time course of recognition of novel melodies

Seven experiments explored the time course of recognition of brief novel melodies. In a continuous-running-memory task, subjects recognized melodic transpositions following delays up to 2.0 min. The delays were either empty or filled with other melodies. Test items included exact transpositions (T), same-contour lures (SC) with altered pitch intervals, and different-contour lures (DC). DCs differed from Ts in the pattern of ups and downs of pitch. With this design, we assessed subjects’ discrimination of detailed changes in pitch intervals (T/SC discrimination) as well as their discrimination of contour changes (T/DC). We used both artificial and “real” melodies. Artificial melodies differed in conformity to a musical key, being tonal or atonal. After empty delays, T/DC discrimination was superior to T/SC discrimination. Surprisingly, after filled delays, T/SC discrimination was superior to T/DC. When only filled delays were tested, T/SC discrimination did not decline over the longest delays. T/DC performance declined more than did T/SC performance across both empty and filled delays. Tonality was an important factor only for T/SC discrimination after filled delays. T/DC performance was better with rhythmically intact folk melodies than with artificial isochronous melodies. Although T/SC performance improved over filled delays, it did not overtake T/DC performance. These results suggest that (1) contour and pitch-interval information make different contributions to recognition, with contour dominating performance after brief empty delays and pitch intervals dominating after longer filled delays; (2) a coherent tonality facilitates the encoding of pitch-interval patterns of melodies; and (3) the rich melodic—rhythmic contours of real melodies facilitate T/DC discrimination. These results are discussed in terms of automatic and controlled processing of melodic information.     

Tonal strength and melody recognition after long and short delays.

In a continuous-running-memory task, subjects heard novel seven-note melodies that were tested after delays of 11 sec (empty) or 39 sec (filled). Test items were transposed to new pitch levels (to moderately distant keys in the musical sense) and included exact transpositions (targets), same-contour lures with altered pitch intervals, and new-contour lures. Melodies differed in tonal strength (degree of conformity to a musical key) and were tonally strong, tonally weak, or atonal. False alarms to same-contour lures decreased over the longer delay period, but only for tonal stimuli. In agreement with previous studies, discrimination of detailed changes in pitch intervals improved with increased delay, whereas discrimination of more global contour information declined, again only for tonal stimuli. These results suggest that poor short-delay performance in rejecting same-contour lures arises from confusion that is based on the similarity of tonality between standard stimuli and lures. If a test item has the same contour and a similar tonality to a just-presented item, subjects tend to accept it. After a delay filled with melodies in other tonalities, the salience of key information recedes, and subjects base their judgments on more detailed pattern information (namely, exact pitch intervals). The fact that tonality affects judgments of melodic contour indicates that contour is not an entirely separable feature of melodies but rather that a melody with its contour constitutes an integrated perceptual whole.     

Tonal strength and melody recognition after long and short delays

In a continuous-running-memory task, subjects heard novel seven-note melodies that were tested after delays of 11 sec (empty) or 39 sec (filled). Test items were transposed to new pitch levels (to moderately distant keys in the musical sense)and included exact transpositions (targets), same-contour lures with altered pitch intervals, and new-contour lures. Melodies differed in tonal strength (degree of conformity to a musical key) and were tonally strong, tonally weak, or atonal. False alarms to same-contour lures decreased over the longer delay period, but only for tonal stimuli. In agreement with previous studies, discrimination of detailed changes in pitch intervals improved with increased delay, whereas discrimination of more global contour information declined, again only for tonal stimuli. These results suggest that poor short-delay performance in rejecting same-contour lures arises from confusion that is based on the similarity of tonality between standard stimuli and lures. If a test item has the same contour and a similar tonality to a just-presented item, subjects tend to accept it. After a delay filled with melodies in other tonalities, the salience of key information recedes, and subjects base their judgments on more detailed pattern information (namely, exact pitch intervals). The fact that tonality affects judgments of melodic contour indicates that contour is not an entirely separable feature of melodies but rather that a melody with its contour constitutes an integrated perceptual whole.     

Children's perception of melodies: the role of contour, frequency, and rate of presentation

Children 4 to 6 years of age were exposed to repetitions of a six-tone melody, then tested for their detection of transformations that either preserved or changed the contour of the standard melody. Discrimination performance was examined as a function of contour condition, magnitude of contour change, rate of presentation, and the presence of novel frequencies. Performance was superior for transformations that changed contour compared to those that did not, for greater changes in contour, and for faster presentation rates. Melodies transformed by a reordering of component tones were no less discriminable than those transformed by the addition of novel frequencies.