Biology subjects

Yasuhara, M.

Publications and source records attributed to Yasuhara, M..

3 recordsLinked to original sources

bioRxiv2026

Humans could become the greatest driver of biosphere net gain in Earth history, but we are currently the second fastest driver of biosphere loss

Human activity is transforming the shape, size, and resilience of Earths biosphere, degrading and augmenting Holocene baseline conditions at various scales, and replacing the wild biosphere with an anthropogenically modified one. We evaluate episodes of biosphere change throughout Earth history and compare them with contemporary and near-future anthropogenic changes, developing the concept of biosphere disruptors - agents that force global-scale macroevolutionary change. Transient disruptors are short-lived agents (mean 8.0x105 years), including massive volcanism and asteroid impacts. Persistent disruptors, including atmospheric and ocean oxygenation and land plant evolution, remain in the Earth System over long timescales (mean 1.6x108 years). In the geological record, transient disruptors are associated with temporary but sometimes massive biosphere degradation, whereas persistent disruptors are associated with sustained biosphere enhancement. Most anthropogenic biosphere impacts resemble those of past transient disruptors, globally degrading wild biomass and biodiversity. Humanity is driving the second highest rate of biosphere degradation in Earth history after the Cretaceous-Palaeogene bolide impact. However, humanity is the first disrupting agent capable of reflecting on and potentially transforming its impact on planetary habitability. If we can achieve this, humanity could drive the greatest rate of increase in planetary habitability in Earth history on centennial to millennial timescales.

paleontology↗

bioRxiv2023

Robustness and adaptability of sensorimotor skills in expert piano performance

Skillful execution of sequential actions requires the delicate balance of sensorimotor control, encompassing both robustness and adaptability. Previous studies have characterized behavioral and electrophysiological responses to sensory perturbation during performance of sequential movements such as speech and singing. However, it remains unknown whether and in what manner both motor and neural responses, triggered by sensory perturbation, undergo plastic adaptation as a consequence of extensive sensorimotor experience. Here, we addressed this question by comparing effects of transiently delayed tone production on the spatiotemporal patterns of the subsequent motor actions and event-related potentials (ERPs) during fast and accurate piano performance between expert pianists and musically-untrained individuals (non-musicians). Following the delayed tone production, the inter-keystroke interval was abnormally prolonged in non-musicians but not in pianists. By contrast, the keystroke velocity following the tone delay was increased only in the pianists. A regression model further demonstrated that the change in the inter-keystroke interval following the perturbation covaried with the ERPs of the N180 and P300 components particularly at the frontal and parietal regions. In contrast, the alteration in the keystroke velocity was associated with the P300 component of the temporal region ipsilateral to the moving hand, which suggests enhancement of auditory but not somatosensory feedback gain following auditory perturbation. Together, these findings suggest that distinct neural mechanisms underlie robust and adaptive sensorimotor skills individuals with different levels of proficiency.

neuroscience↗

bioRxiv2023

Brain network flexibility as a predictor of skilled musical performance

Interactions between the body and the environment are dynamically modulated by upcoming sensory information and motor execution. To adapt to this behavioral state-shift, brain activity must also be flexible and possess a large repertoire of brain networks so as to switch them flexibly. Recently, flexible internal brain communications, i.e., brain network flexibility, have come to be recognized as playing a vital role in integrating various sensorimotor information. Therefore, brain network flexibility may be one of the key factors that define sensorimotor skill. However, little is known about how flexible communications within a brain characterizes inter-individual variation of sensorimotor skill and trial-by-trial variability within individuals. To address this, we recruited highly skilled musical performers (i.e. brass instrumentalists) and used a novel approach that combined multichannel-scalp electroencephalography (EEG) recordings, behavioral measurements of musical performance, and mathematical approaches to extract brain network flexibility. We found that brain network flexibility immediately before initiating the performance predicted inter-individual differences in the precision of tone timbre (as represented by spectral centroid of the sound), but not trial-by-trial variability at the individual level. Furthermore, brain network flexibility in broader cortical regions, rather than specific local cortical regions, predicted skilled musical performance, indicating that whole-cortical fluctuations determine individual skill. Our results provide novel evidence that brain network flexibility during movement preparation plays an important role in skilled sensorimotor performance and our findings have potentials for designing a new approach to predict an individuals skill from neural dynamics and a new intervention tool to facilitate physical education.

neuroscience↗