Biology subjects

Sakata, J.

Publications and source records attributed to Sakata, J..

6 recordsLinked to original sources

bioRxiv2025

Humans, but not songbirds, produce spontaneously isochronous song through the lifespan

Isochrony - as in the regular beat of a metronome - is cross-culturally ubiquitous in music. Is this ubiquity due to a widespread biological inclination for acoustic communication having isochronous structure? If so, it should be present in lesser-studied vocal music, in the absence of musical training, and in comparable non-human species vocalizations. We quantified isochrony in an untrained expression of musicality: improvised songs from non-musician adults and children. We also tested for isochrony in songs from zebra finches, a bird that learns complex songs. We analyzed improvised songs from children (n = 38, 3-10 years old) and adult non-musicians (n = 15, 24-82 years old), and songs from juvenile and adult zebra finches (n= 77, [~]50 and 120 days post-hatch, respectively). Isochrony was expressed in non-musicians improvised songs, and in childrens improvised songs to a comparable degree. In contrast, both juvenile and adult zebra finches produced songs with less isochrony than chance. And although zebra finches learn sequences and durations of their songs elements, we found no evidence for the learning of isochrony. These data show that spontaneous isochrony in learned vocalizations appears differently across these two species. We propose that species variation in chorusing behaviors may explain why.

animal behavior and cognition↗

bioRxiv2024

Pervasive patterns in the songs of passerine birds resemble human music universals and are linked with production and cognitive mechanisms

Music is a complex learned behavior that is ubiquitous among humans, and many musical patterns are shared across geography and cultures ("music universals"). Knowing whether these universals are specific to humans or shared with other animals is important to understand how production-related factors (motor biases and constraints) or cognitive factors (learning) contribute to the emergence of these acoustic patterns. Bird song is often described as an animal analogue of human music, and some studies of individual avian species highlight acoustic similarities between bird song and music. However, expansive and comparative approaches are necessary to identify universal patterns within bird song, reveal mechanisms associated with these patterns, and draw parallels to music universals. Here, we adopt such an approach and analyze the prevalence of acoustic patterns (sequences) across [~]300 species of passerines, spanning both oscines (songbirds; vocal learners) and their sister clade, suboscines (passerines that produce songs that are not learned), as well as within a global corpus of human vocal music. This approach allowed us to directly test hypotheses that phonation mechanisms or vocal learning shape the emergence of universal patterns. We first document acoustic patterns that were widely shared across passerines and similar to music universals (e.g., small pitch intervals), highlighting the role of shared vocal production mechanisms in these patterns. Consistent with a contribution of vocal learning, we observed patterns (e.g., alternation in durations) there were more similar between oscines and humans than between suboscines and humans. Interestingly, we also discovered patterns (e.g., pitch alternation) that were inconsistent with a contribution of vocal learning and were more similar between suboscines and humans than between oscines and humans. This research provides the broadest evidence of shared universals in vocal performance across birds and humans and highlights convergent mechanisms shaping communication patterns.

animal behavior and cognition↗

bioRxiv2024

Perineuronal nets in motor circuitry regulate the performance of learned vocalizations in songbirds

The accurate and reliable production of learned behaviors can be important for survival and reproduction; for example, the performance of learned vocalizations (e.g., speech and birdsong) modulates the efficacy of social communication in humans and songbirds. Consequently, it is critical to understand the factors that regulate the performance of learned behaviors. Across various taxa, neural circuits that regulate motor learning are replete with perineuronal nets (PNNs), extracellular matrices that surround neurons and shape neural dynamics and plasticity. Perineuronal nets in circuits for sensory and cognitive processes have been found to affect sensory processing and behavioral plasticity. However, the function of PNNs in motor circuits remains largely unknown. Here, we analyzed the causal contribution of PNNs in motor circuitry to the performance of learned vocalizations in songbirds. Songbirds like the zebra finch are powerful models for this endeavor because the performance of their learned songs is regulated by activity within discrete and specialized circuits (i.e., song system) that are dense with PNNs. We first report that developmental increases in the density and intensity of PNNs throughout the song system [including in the motor nucleus HVC (acronym used as proper name)] are associated with developmental increases in song performance. We next discovered that enzymatically degrading PNNs in HVC acutely affected song performance. In particular, PNN degradation caused song structure to deviate from pre-surgery song due to changes in syllable sequencing and production. Collectively, our data provide compelling evidence for a causal contribution of PNNs to the performance of learned behaviors. SIGNIFICANCE STATEMENTMotor circuits are replete with perineuronal nets (PNNs) but little is known about their contribution to motor performance. Here, we analyzed how PNNs within vocal motor circuits modulate the ability of songbirds to consistently produce their learned songs. We report that developmental increases in PNN expression in vocal circuitry were associated with developmental increases in the ability to consistently perform their learned song. Moreover, degrading PNNs in the vocal motor nucleus HVC reduced the ability of adult birds to accurately produce their learned song. Our findings indicate a causal contribution of PNNs in motor circuitry to the performance of learned behaviors and, because PNNs are expressed in brain areas regulating speech, suggest that PNNs could modulate speech production in humans.

neuroscience↗

bioRxiv2023

Cross-species conservation in the regulation of parvalbumin by perineuronal nets

Parvalbumin (PV) neurons play an integral role in regulating neural dynamics and plasticity. Therefore, understanding the factors that regulate PV expression is important for revealing modulators of brain function. While the contribution of PV neurons to neural processes has been studied in mammals, relatively little is known about PV function in non-mammalian species, and discerning similarities in the regulation of PV across species can provide insight into evolutionary conservation in the role of PV neurons. Here we investigated factors that affect the abundance of PV in PV neurons in sensory and motor circuits of songbirds and rodents. In particular, we examined the degree to which perineuronal nets (PNNs), extracellular matrices that preferentially surround PV neurons, modulate PV abundance as well as how the relationship between PV and PNN expression differs across brain areas and species and changes over development. We generally found that cortical PV neurons that are surrounded by PNNs (PV+PNN neurons) are more enriched with PV than PV neurons without PNNs (PV-PNN neurons) across both rodents and songbirds. Interestingly, the relationship between PV and PNN expression in the vocal portion of the basal ganglia of songbirds (Area X) differed from that in other areas, with PV+PNN neurons having lower PV expression compared to PV-PNN neurons. These relationships remained consistent across development in vocal motor circuits of the songbird brain. Finally, we discovered a causal contribution of PNNs to PV expression in songbirds because degradation of PNNs led to a diminution of PV expression in PV neurons. These findings in reveal a conserved relationship between PV and PNN expression in sensory and motor cortices and across songbirds and rodents and suggest that PV neurons could modulate plasticity and neural dynamics in similar ways across songbirds and rodents.

neuroscience↗

bioRxiv2023

Sex Differences in Human Music Perception are Negligible

Since Darwin1, researchers have proposed that human musicality evolved in a reproductive context in which males produce music to signal their mate quality to females. Sexually selected traits involve tradeoffs in the costs of high-quality signal production and high-fidelity signal detection2, leading to observable sexual dimorphisms across many species3,4. If musicality is a sexually selected trait in humans, males and females should then differ in their music perception ability, music production ability, or both. The evidence for this possibility is unclear, because previous reports of sex differences in human auditory perception are restricted in scope and inconsistent in direction5-15. Here, we report a test of music processing ability in 360,009 men and 194,291 women from 208 countries. In contrast to other non-musical human traits16-19, and in contrast to music-related traits in non-human animals20-23, we found no consistent advantage for either sex. The sex differences we did observe were negligible (Cohens d range: 0.009-0.111) and Bayesian analyses indicated evidence in favor of the null hypothesis of no sex difference in general musical ability (Bayes Factor = 0.6). These results suggest that it is unlikely that music evolved in the context of sexual selection.

animal behavior and cognition↗

bioRxiv2020

Introductory gestures before songbird vocal displays are shaped by learning and biological predispositions

Introductory gestures are present at the beginning of many animal displays. For example, lizards start their head-bobbing displays with introductory push-ups and animal vocal displays begin with introductory notes. Songbirds also begin their vocal displays by repeating introductory notes (INs) before producing their learned song and these INs are thought to reflect motor preparation. Between individuals of a given species, the acoustic structure of INs and the number of times INs are repeated before song varies considerably. While similar variation in songs between individuals is known to be a result of learning, whether INs are also learned remains poorly understood. Here, using natural and experimental tutoring with male zebra finches, we show that mean IN number and IN acoustic structure are learned from a tutor, independent of song learning. We also reveal biological predispositions in IN production; birds artificially tutored with songs lacking INs still repeated a short-duration syllable, thrice on average, before their songs. Overall, these results show that INs, just like elements in song, are shaped both by learning and biological predispositions and suggest multiple, independent, learning processes underlying the acquisition of complex vocal displays.

animal behavior and cognition↗