Relative Pitch Perception Research Articles

Perception and learning of relative pitch by musicians using the vibrotactile mode

This study investigated the perception and learning of relative pitch using vibrotactile stimuli by musicians with and without a hearing impairment. Notes from C3 to B4 were presented to the fingertip and forefoot. Pre- and post-training tests in which 420 pairs of notes were presented randomly were carried out without any feedback to participants. After the pre-training test, 16 short training sessions were carried out over six weeks with 72 pairs of notes per session and participants told whether their answers were correct. For amateur and professional musicians with normal hearing and professional musicians with a severe or profound hearing loss, larger pitch intervals were easier to identify correctly than smaller intervals. Musicians with normal hearing had a high success rate for relative pitch discrimination as shown by pre- and post-training tests, and when using the fingertips, there was no significant difference between amateur and professional musicians. After training, median scores on the tests in which stimuli were presented to the fingertip and forefoot were >70% for intervals of 3–12 semitones. Training sessions reduced the variability in the responses of amateur and professional musicians with normal hearing and improved their overall ability. There was no significant difference between the relative pitch discrimination abilities between one and 11 semitones, as shown by the pre-training test, of professional musicians with and without a severe/profound hearing loss. These findings indicate that there is potential for vibration to be used to facilitate group musical performance and music education in schools for the deaf.

Song Is More Memorable Than Speech Prosody: Discrete Pitches Aid Auditory Working Memory.

Vocal music and spoken language both have important roles in human communication, but it is unclear why these two different modes of vocal communication exist. Although similar, speech and song differ in certain design features. One interesting difference is in the pitch intonation contour, which consists of discrete tones in song, vs. gliding intonation contours in speech. Here, we investigated whether vocal phrases consisting of discrete pitches (song-like) or gliding pitches (speech-like) are remembered better, conducting three studies implementing auditory same-different tasks at three levels of difficulty. We tested two hypotheses: that discrete pitch contours aid auditory memory, independent of musical experience (“song memory advantage hypothesis”), or that the higher everyday experience perceiving and producing speech make speech intonation easier to remember (“experience advantage hypothesis”). We used closely matched stimuli, controlling for rhythm and timbre, and we included a stimulus intermediate between song-like and speech-like pitch contours (with partially gliding and partially discrete pitches). We also assessed participants' musicality to evaluate experience-dependent effects. We found that song-like vocal phrases are remembered better than speech-like vocal phrases, and that intermediate vocal phrases evoked a similar advantage to song-like vocal phrases. Participants with more musical experience were better in remembering all three types of vocal phrases. The precise roles of absolute and relative pitch perception and the influence of top-down vs. bottom-up processing should be clarified in future studies. However, our results suggest that one potential reason for the emergence of discrete pitch–a feature that characterises music across cultures–might be that it enhances auditory memory.

Categorical Auditory Working Memory in Crows.

SummaryThe ability to group sensory data into behaviorally meaningful classes and to maintain these perceptual categories active in working memory is key to intelligent behavior. Here, we show that carrion crows, highly vocal and cognitively advanced corvid songbirds, possess categorical auditory working memory. The crows were trained in a delayed match-to-category task that required them to flexibly match remembered sounds based on the upward or downward shift of the sounds' frequency modulation. After training, the crows instantaneously classified novel sounds into the correct auditory categories. The crows showed sharp category boundaries as a function of the relative frequency interval of the modulation. In addition, the crows generalized frequency-modulated sounds within a category and correctly classified novel sounds kept in working memory irrespective of other acoustic features of the sound. This suggests that crows can form and actively memorize auditory perceptual categories in the service of cognitive control of their goal-directed behaviors.

Benefit of tonal context on relative pitch perception in musicians and non-musicians

The ability to access pitch differences between successive notes is essential for recognition of melodies and enables the detection of wrong tones in a familiar melody. The ability to compare pitch interval size is generally poor when the tones are presented without context but might improve if embedded in a tonal context. The present study measured pitch interval discrimination and aimed to determine (1) the effect of tonal context (novel or familiar melody), (2) the effect of standard interval size (2 and 9 semitones) and (3) the effect of musical training including ear training. Musicians and non-musicians between 18 and 30 years were tested. The musicians had played/sung for at least 5 years, had at least 1 semester of ear training, and still played/sung. The non-musicians had played for maximum 5 years, never had ear training lessons, and did not currently play/sing. The preliminary results show a benefit of tonal context for context presented before but not after the target interval. The benefit of the musicians is similar for the familiar and novel melodies whereas the performance of the non-musicians is markedly better for familiar compared to novel melodies. Performance is generally better for the smaller standard interval.

Vowel Content Influences Relative Pitch Perception in Vocal Melodies

Note-to-note changes in brightness are able to influence the perception of interval size. Changes that are congruent with pitch tend to expand interval size, whereas changes that are incongruent tend to contract. In the case of singing, brightness of notes can vary as a function of vowel content. In the present study, we investigated whether note-to-note changes in brightness arising from vowel content influence perception of relative pitch. In Experiment 1, three-note sequences were synthesized so that they varied with regard to the brightness of vowels from note to note. As expected, brightness influenced judgments of interval size. Changes in brightness that were congruent with changes in pitch led to an expansion of perceived interval size. A follow-up experiment confirmed that the results of Experiment 1 were not due to pitch distortions. In Experiment 2, the final note of three-note sequences was removed, and participants were asked to make speeded judgments of the pitch contour. An analysis of response times revealed that brightness of vowels influenced contour judgments. Changes in brightness that were congruent with changes in pitch led to faster response times than did incongruent changes. These findings show that the brightness of vowels yields an extra-pitch influence on the perception of relative pitch in song.

Neural patterns reveal single-trial information on absolute pitch and relative pitch perception

Pitch is a fundamental attribute of sounds and yet is not perceived equally by all humans. Absolute pitch (AP) musicians perceive, recognize, and name pitches in absolute terms, whereas relative pitch (RP) musicians, representing the large majority of musicians, perceive pitches in relation to other pitches. In this study, we used electroencephalography (EEG) to investigate the neural representations underlying tone listening and tone labeling in a large sample of musicians (n = 105). Participants performed a pitch processing task with a listening and a labeling condition during EEG acquisition. Using a brain-decoding framework, we tested a prediction derived from both theoretical and empirical accounts of AP, namely that the representational similarity of listening and labeling is higher in AP musicians than in RP musicians. Consistent with the prediction, time-resolved single-trial EEG decoding revealed a higher representational similarity in AP musicians during late stages of pitch perception. Time-frequency-resolved EEG decoding further showed that the higher representational similarity was present in oscillations in the theta and beta frequency bands. Supplemental univariate analyses were less sensitive in detecting subtle group differences in the frequency domain. Taken together, the results suggest differences between AP and RP musicians in late pitch processing stages associated with cognition, rather than in early processing stages associated with perception.

Vowel content influences relative pitch perception in vocal melodies: A comparison of models based on brightness vs. intrinsic pitch of vowels

Past research involving real and synthesized instrumental timbres has found that note-to-note changes in brightness can influence perception of interval size. Changes that are congruent with changes in pitch led to an expansion, whereas changes that are incongruent lead to a contraction. In the case of singing, the brightness of individual notes (as measured by the spectral centroid) will vary as a function of vowel content. In a recent study, we investigated whether note-to-note changes in the brightness of sung notes were capable of influencing the perception of interval size. While results were consistent with past work on instrumental timbres, we were not able to completely rule out an alternative explanation concerning a perceptual correction for the intrinsic pitch of vowels (e.g., f0 of /i/ tends to be produced higher than /a/). In the present study, we created 288 unique note pairs that varied with regard to absolute change in f0 as well as vowel content. Vowels were sampled from across the vowel space, which allowed us to generate unique predictors for change in brightness (spectral centroid) and changes in intrinsic pitch (F2). Regression analyses will compare the effectiveness of competing models.

Perception of relative pitch of sentence-length utterances.

Differences in relative pitch have several linguistic uses, such as tone and dynamic intonational patterns. In addition, listeners are also sensitive to average pitch differences both within and across male and female speakers. While much research uses isolated syllables to investigate how well listeners can distinguish differences in pitch, this study focuses on listeners' ability to identify relative pitch differences across whole utterances. Listeners are presented with 28 items of the same sentence spoken by female politicians and are asked to rate how low or high the pitch of the utterance is on a 5-point scale. Results indicate that listeners use all steps of the scale to categorize the mean F0 of the stimuli (range: 130-250 Hz) and not a "high/medium/low" system or one in which only the extremes are categorized as high or low.

Differences in sound perception are reflected by individual auditory fingerprints in musicians

Musicians have been reported to show significant inter-Individual differences in elementary hearing functions, sound perception mode, musical instrument preference, performance style, as well as more complex musical abilities like absolute- and relative pitch perception, and auditory imagery. However, it remains unexplored how individual elementary hearing functions and corresponding musical abilities are inter-connected and to what extend they reflect individual differences in the musical behavior of musicians. Using a combination of five listening tests and assessing resulting psychoacoustic parameters, we were able to determine individual auditory fingerprints on the single subject- and group level. 93 musicians (49 professionals and 44 amateurs) were individually tested for: frequency discrimination threshold, holistic and spectral sound perception, absolute pitch perception, relative pitch perception (musical interval recognition), and musical imagery (AMMA). On the individual level, our results show that auditory fingerprints differ remarkably between subjects. On the group level, using PCA and cluster analysis, we found four main components represented significantly different in the three characteristic clusters of subjects. Taken together, our findings suggest that inter-individual differences in the auditory fingerprint reflect the high variability of individual sound perception and may have crucial impact on specific musical preference, style and performance of musicians.

Relative Pitch Perception and the Detection of Deviant Tone Patterns.

Most people are able to recognise familiar tunes even when played in a different key. It is assumed that this depends on a general capacity for relative pitch perception; the ability to recognise the pattern of inter-note intervals that characterises the tune. However, when healthy adults are required to detect rare deviant melodic patterns in a sequence of randomly transposed standard patterns they perform close to chance. Musically experienced participants perform better than naïve participants, but even they find the task difficult, despite the fact that musical education includes training in interval recognition.To understand the source of this difficulty we designed an experiment to explore the relative influence of the size of within-pattern intervals and between-pattern transpositions on detecting deviant melodic patterns. We found that task difficulty increases when patterns contain large intervals (5-7 semitones) rather than small intervals (1-3 semitones). While task difficulty increases substantially when transpositions are introduced, the effect of transposition size (large vs small) is weaker. Increasing the range of permissible intervals to be used also makes the task more difficult. Furthermore, providing an initial exact repetition followed by subsequent transpositions does not improve performance. Although musical training correlates with task performance, we find no evidence that violations to musical intervals important in Western music (i.e. the perfect fifth or fourth) are more easily detected. In summary, relative pitch perception does not appear to be conducive to simple explanations based exclusively on invariant physical ratios.

Chorusing, synchrony, and the evolutionary functions of rhythm.

A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc.) with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony), we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, arguing that group behavior is key to understanding the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates). Finally, we propose an “Evolving Signal Timing” hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s) of rhythmic behavior in our “proto-musical” primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and language.

A cochlear implant user with exceptional musical hearing ability

Although the perception of music is generally poor in cochlear implant users, there are a few excellent performers. Objective: The aim of this study was the assessment of different aspects of music perception in one exceptional cochlear implant user. Design: The assessments included pitch direction discrimination, melody and timbre recognition, relative and absolute pitch judgment, and consonance rating of musical notes presented through the sound processor(s). Study sample: An adult cochlear implant user with musical background who lost her hearing postlingually, and five normally-hearing listeners with musical training participated in the study. Results: The CI user discriminated pitch direction for sounds differing by one semitone and recognized melody with nearly 100% accuracy. Her results in timbre recognition were better than average published data for cochlear implant users. Her consonance rating, and relative and absolute pitch perception were comparable to normally-hearing listeners with musical training. Conclusion: The results in this study showed that excellent performance is possible on musical perception tasks including pitch perception using present day cochlear implant technologies. Factors that may explain this user's exceptional performance are short duration of deafness, pre- and post-deafness musical training, and perfect pitch abilities before the onset of deafness.

The Role of Pitch Memory in Music Perception

The purpose of this paper is to review pitch memory, one of the less known aspects of music perception. In order to successfully perceive music, it is necessary to compare the pitch of successive notes in order to appreciate and recognize melodies. The process of recognizing and comparing the pitch of successive notes is called relative pitch. Pitch memory is important in the perception of relative pitch because it is necessary to hold the pitch of one note in memory momentarily before the next note is presented. Pitch memory is evaluated by altering a pitch discrimination task by placing silent intervals or intervals containing interference stimuli (e.g., noise, tones, speech) between the reference and comparison tones. Overall, research in this area suggests a significant relationship between pitch discrimination ability and pitch memory, and between pitch matching ability and pitch memory. Various stimulus and individual factors can also affect pitch memory ability.

Pitch contour identification with combined place and temporal cues using cochlear implants

This study investigated the integration of place- and temporal-pitch cues in pitch contour identification (PCI), in which cochlear implant (CI) users were asked to judge the overall pitch-change direction of stimuli. Falling and rising pitch contours were created either by continuously steering current between adjacent electrodes (place pitch), by continuously changing amplitude modulation (AM) frequency (temporal pitch), or both. The percentage of rising responses was recorded as a function of current steering or AM frequency change, with single or combined pitch cues. A significant correlation was found between subjects' sensitivity to current steering and AM frequency change. The integration of place- and temporal-pitch cues was most effective when the two cues were similarly discriminable in isolation. Adding the other (place or temporal) pitch cues shifted the temporal- or place-pitch psychometric functions horizontally without changing the slopes. PCI was significantly better with consistent place- and temporal-pitch cues than with inconsistent cues. PCI with single cues and integration of pitch cues were similar on different electrodes. The results suggest that CI users effectively integrate place- and temporal-pitch cues in relative pitch perception tasks. Current steering and AM frequency change should be coordinated to better transmit dynamic pitch information to CI users.

Do ferrets perceive relative pitch?

The existence of relative pitch perception in animals is difficult to demonstrate, since unlike humans, animals often attend to absolute rather than relative properties of sound elements. However, the results of the present study show that ferrets can be trained using relative pitch to discriminate two-tone sequences (rising vs. falling). Three ferrets were trained using a positive-reinforcement paradigm in which sequences of reference (one to five repeats) and target stimuli were presented, and animals were rewarded only when responding correctly to the target. The training procedure consisted of three training phases that successively shaped the ferrets to attend to relative pitch. In Phase-1 training, animals learned the basic task with sequences of invariant tone-pairs and could use absolute pitch information. During Phase-2 training, in order to emphasize relative cues, absolute pitch was varied each trial within a two-octave frequency range. In Phase-3 training, absolute pitch cues were removed, and only relative cue information was available to solve the task. Two ferrets successfully completed training on all three phases and achieved significant discriminative performance over the trained four-octave frequency range. These results suggest that ferrets can be trained to discern the relative pitch relationship of a sequence of tone-pairs independent of frequency.

Dual Time Scales for Categorical Decision Making in Auditory Cortex

Category formation allows us to group perceptual objects into meaningful classes and is fundamental to cognition. Categories can be derived from similarity relationships of object features by using prototypes or multiple exemplars, or from abstract relationships of features and rules . A variety of brain areas have been implicated in categorization processes, but mechanistic insights on the single-cell and local-network level are still rare and limited to the matching of individual objects to categories . For directional categorization of tone steps, as in melody recognition , abstract relationships between sequential events (higher or lower in frequency) have to be formed. To explore the neuronal mechanisms of this categorical identification of step direction, we trained monkeys for more than two years on a contour-discrimination task with multiple tone sequences. In the auditory cortex of these highly trained monkeys, we identified two interrelated types of neuronal firing: Increased phasic responses to tones categorically represented the reward-predicting downward frequency steps and not upward steps; subsequently, slow modulations of tonic firing predicted the behavioral decisions of the monkeys, including errors. Our results on neuronal mechanisms of categorical stimulus identification and of decision making attribute a cognitive role to auditory cortex, in addition to its role in signal processing.

Relative pitch perception in Japanese monkeys (Macaca fuscata).

Relative pitch perception in Japanese monkeys (Macaca fuscata).

Relative pitch perception in Japanese monkeys (Macaca fuscata).

To investigate whether monkeys perceive relative pitch, the author trained 3 Japanese monkeys (Macaca fuscata) to detect changes from rising to falling contours of 3-tone sequences. Tone sequences were presented serially with transposition, so monkeys were urged to attend to cues other than the absolute frequency of a component tone. Results from probe tests with novel sequences showed that monkeys discriminated by the relative pitch when the frequency ranges of sequences were within the training range, showing a similar tendency as birds in previous studies (e.g., S. H. Hulse, J. Cynx, & J. Humpal, 1984).

Neural Processing and Representation of Periodicity Pitch

Periodic signals are generated by vocal chords and many other physical sound sources. A theory of temporal analysis of such periodic signals is presented which is adequate to explain details of response properties of neurons in the auditory midbrain as well as psychophysical pitch effects. According to this theory, such signals are coded in the temporal domain by neuronal activity synchronized to the signal periodicities and are processed by neuronal mechanisms, involving intrinsic oscillations synchronized to signal envelope, temporal integration of signal fine structure, and coincidence detection. Spikes from the oscillator and the integrator have different delays and may coincide only when the envelope periodicity is adequate for the compensation of this difference. Neurons in the auditory midbrain function as corresponding coincidence detectors and transfer the temporal information into a rate-place code. Coincidence neurons are arranged topographically, orthogonal to the tonotopic organization in the midbrain. An orthogonal representation of pitch and frequency was found also in the human auditory cortex. This theory allows to relate neuronal processing to certain auditory percepts. It may be adequate to provide the adequate framework for the understanding of relative and absolute pitch perception.

Concurrent absolute and relative pitch processing by European starlings (Sturnus vulgaris).

In responding to sounds, birds use both relative and absolute pitch perception. As a means of testing which type of pitch perception is dominant, European starlings (Sturnus vulgaris) were trained to discriminate between low-ascending and high-descending sequences of tones. They were then tested with high-ascending and low-descending sequences during probe and transfer sessions. The birds could transfer their discrimination on the basis of either high versus low (absolute pitch) or ascending versus descending (relative pitch). During probe sessions, birds responded to nonreinforced novel sequences on the basis of absolute pitch. However, during transfer sessions, the birds could quickly learn to respond to reinforced novel sequences on the basis of relative pitch. The results indicate that during initial training, the birds learned about both relative and absolute aspects of the stimuli.