A Theory of Instrument-Specific Absolute Pitch

Should absolute pitch be considered as a unique kind of absolute sensory judgment in humans? A systematic and theoretical review of the literature

Absolute pitch is the name given to the rare ability to identify a musical note in an automatic and effortless manner without the need for a reference tone. Those individuals with absolute pitch can, for example, name the note they hear, identify all of the tones of a given chord, and/or name the pitches of everyday sounds, such as car horns or sirens. Hence, absolute pitch can be seen as providing a rare example of absolute sensory judgment in audition. Surprisingly, however, the intriguing question of whether such an ability presents unique features in the domain of sensory perception, or whether instead similar perceptual skills also exist in other sensory domains, has not been explicitly addressed previously. In this paper, this question is addressed by systematically reviewing research on absolute pitch using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) method. Thereafter, we compare absolute pitch with two rare types of sensory experience, namely synaesthesia and eidetic memory, to understand if and how these phenomena exhibit similar features to absolute pitch. Furthermore, a common absolute perceptual ability that has been often compared to absolute pitch, namely colour perception, is also discussed. Arguments are provided supporting the notion that none of the examined abilities can be considered like absolute pitch. Therefore, we conclude by suggesting that absolute pitch does indeed appear to constitute a unique kind of absolute sensory judgment in humans, and we discuss some open issues and novel directions for future research in absolute pitch.

Temporal hierarchy of cortical responses reflects core-belt-parabelt organization of auditory cortex in musicians

Human auditory cortex (AC) organization resembles the core-belt-parabelt organization in nonhuman primates. Previous studies assessed mostly spatial characteristics; however, temporal aspects were little considered so far. We employed co-registration of functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) in musicians with and without absolute pitch (AP) to achieve spatial and temporal segregation of human auditory responses. First, individual fMRI activations induced by complex harmonic tones were consistently identified in four distinct regions-of-interest within AC, namely in medial Heschl's gyrus (HG), lateral HG, anterior superior temporal gyrus (STG), and planum temporale (PT). Second, we analyzed the temporal dynamics of individual MEG responses at the location of corresponding fMRI activations. In the AP group, the auditory evoked P2 onset occurred ~25 ms earlier in the right as compared with the left PT and ~15 ms earlier in the right as compared with the left anterior STG. This effect was consistent at the individual level and correlated with AP proficiency. Based on the combined application of MEG and fMRI measurements, we were able for the first time to demonstrate a characteristic temporal hierarchy ("chronotopy") of human auditory regions in relation to specific auditory abilities, reflecting the prediction for serial processing from nonhuman studies.

Generalizing across tonal context, timbre, and octave in rapid absolute pitch training

Absolute pitch (AP) is the rare ability to name any musical note without the use of a reference note. Given that genuine AP representations are based on the identification of isolated notes by their tone chroma, they are considered to be invariant to (1) surrounding tonal context, (2) changes in instrumental timbre, and (3) changes in octave register. However, there is considerable variability in the literature in terms of how AP is trained and tested along these dimensions, making recent claims about AP learning difficult to assess. Here, we examined the effect of tonal context on participant success with a single-note identification training paradigm, including how learning generalized to an untested instrument and octave. We found that participants were able to rapidly learn to distinguish C from other notes, with and without feedback and regardless of the tonal context in which C was presented. Participants were also able to partly generalize this skill to an untrained instrument. However, participants displayed the weakest generalization in recognizing C in a higher octave. The results indicate that participants were likely attending to pitch height in addition to pitch chroma - a conjecture that was supported by analyzing the pattern of response errors. These findings highlight the complex nature of note representation in AP, which requires note identification across contexts, going beyond the simple storage of a note fundamental. The importance of standardizing testing that spans both timbre and octave in assessing AP and further implications on past literature and future work are discussed.

An Analysis of Music Perception Skills on Crowdsourcing Platforms

Music content annotation campaigns are common on paid crowdsourcing platforms. Crowd workers are expected to annotate complex music artifacts, a task often demanding specialized skills and expertise, thus selecting the right participants is crucial for campaign success. However, there is a general lack of deeper understanding of the distribution of musical skills, and especially auditory perception skills, in the worker population. To address this knowledge gap, we conducted a user study (N = 200) on Prolific and Amazon Mechanical Turk. We asked crowd workers to indicate their musical sophistication through a questionnaire and assessed their music perception skills through an audio-based skill test. The goal of this work is to better understand the extent to which crowd workers possess higher perceptions skills, beyond their own musical education level and self reported abilities. Our study shows that untrained crowd workers can possess high perception skills on the music elements of melody, tuning, accent, and tempo; skills that can be useful in a plethora of annotation tasks in the music domain.

Effects of Visual and Auditory Feedback in Violin and Singing Voice Pitch Matching Tasks

Auditory-guided vocal learning is a mechanism that operates both in humans and other animal species making us capable to imitate arbitrary sounds. Both auditory memories and auditory feedback interact to guide vocal learning. This may explain why it is easier for humans to imitate the pitch of a human voice than the pitch of a synthesized sound. In this study, we compared the effects of two different feedback modalities in learning pitch-matching abilities using a synthesized pure tone in 47 participants with no prior music experience. Participants were divided into three groups: a feedback group (N = 15) receiving real-time visual feedback of their pitch as well as knowledge of results; an equal-timbre group (N = 17) receiving additional auditory feedback of the target note with a similar timbre to the instrument being used (i.e., violin or human voice); and a control group (N = 15) practicing without any feedback or knowledge of results. An additional fourth group of violin experts performed the same task for comparative purposes (N = 15). All groups were posteriorly evaluated in a transfer phase. Both experimental groups (i.e., the feedback and equal-timbre groups) improved their intonation abilities with the synthesized sound after receiving feedback. Participants from the equal-timber group seemed as capable as the feedback group of producing the required pitch with the voice after listening to the human voice, but not with the violin (although they also showed improvement). In addition, only participants receiving real-time visual feedback learned and retained in the transfer phase the mapping between the synthesized pitch and its correspondence with the produced vocal or violin pitch. It is suggested that both the effect of an objective external reward, together with the experience of exploring the pitch space with their instrument in an explicit manner, helped participants to understand how to control their pitch production, strengthening their schemas, and favoring retention.

Articulatory motor planning and timbral idiosyncrasies as underlying mechanisms of instrument-specific absolute pitch in expert musicians

The study of musical expertise illustrates how intense training in a specialized domain may instigate development of implicit skills. While absolute pitch, or the ability to identify musical pitches without external reference, is rare even in professional musicians and is understood to have a genetic component, anecdotal evidence and pilot data suggest that some musicians without traditional absolute pitch are nonetheless better able to name notes played on their musical instrument of expertise than notes played on less familiar instruments. We have previously termed this particular gain in absolute pitch identification ability “instrument-specific absolute pitch” (ISAP) and have proposed that this skill is related to learned instrument type-specific timbral and intonational idiosyncrasies and articulatory motor planning activated by the timbre of the instrument. In this Registered Report Protocol, we describe two experiments designed to investigate ISAP in professional oboists. Experiment 1 tests for ISAP ability by comparing oboists’ pitch identification accuracies for notes played on the oboe and on the piano. A subset of the participants from Experiment 1 who demonstrate this ability will be recruited for Experiment 2; the purpose of Experiment 2 is to test hypotheses concerning a mechanistic explanation for ISAP. The outcome of these experiments may provide support for the theory that some individuals have ISAP and that the underlying mechanisms of this ability may rely on the perception of subtle timbral/intonational idiosyncrasies and on articulatory motor planning developed through intensive long-term training. In general, this work will contribute to the understanding of specialized expertise, specifically of implicit abilities and biases that are not addressed directly in training, but that may yet develop through practice of a related skill set.