Biology subjects

Daikoku, T.

Publications and source records attributed to Daikoku, T..

10 recordsLinked to original sources

bioRxiv2025

Lifetime changes in Body map based on music prediction

This study aims to investigate the relationship between music, which is said to promote well-being, and emotions as well as bodily sensations across the lifespan. Using eight chord progressions based on predictive models, we conducted online experiments with 784 participants aged 10 to 80, evaluating bodily sensation mapping and emotional responses. The results revealed that bodily sensations peaked in the 20s to 30s and subsequently declined with age, particularly for chords with low prediction error and uncertainty. On the other hand, arousal levels increased with age and showed a strong correlation with predictable musical structures. These findings suggest that bottom-up bodily responses diminish with ageing, while supporting the relationship between top-down processing shaped by accumulated experience and the predictability of music, as indicated by previous research. This study enhances the development of music-based interventions that improve well-being across generations, considering the unique physical and emotional characteristics of each age group.

physiology↗

bioRxiv2024

Neural tracking of auditory statistical regularities is reduced in adults with dyslexia

Listeners implicitly use statistical regularities to segment continuous sound input into meaningful units, e.g., transitional probabilities between syllables to segment a speech stream into separate words. Implicit learning of such statistical regularities in a novel stimulus stream is reflected in a synchronisation of neural responses to the sequential stimulus structure. The present study aimed to test the hypothesis that neural tracking of the statistical stimulus structure is reduced in individuals with dyslexia who have weaker reading and spelling skills, and possibly also weaker statistical learning abilities in general, compared to healthy controls. To this end, adults with and without dyslexia were presented with continuous streams of (non-speech) tones, which were arranged into triplets, such that transitional probabilities between single tones were high within triplets and low between triplets. We found that neural tracking of the triplet structure, i.e., phase coherence of EEG response at the triplet rate relative to the tone rate, was reduced in adults with dyslexia compared to the control group. Moreover, enhanced neural tracking of the statistical structure was associated with better spelling skills. These results suggest that individuals with dyslexia have a rather broad deficit in processing structure in sound instead of a merely phonological deficit.

neuroscience↗

bioRxiv2024

Music-related Bodily Sensation Map in Individuals with Depressive Tendencies

Music has the power to influence peoples emotions. Therefore, music is also used as an intervention to reduce the stress in mental disorders such as depression and anxiety. Recent research has suggested that the body plays a key role in the connection between music and emotion with a correlation between the head sensations and negative emotions while listening to music. Additionally, strong sensations in the head have been suggested as a bodily perception associated with depression. In this study, we investigated the bodily sensations experienced by people with depressive tendencies when listening to music and their association with specific emotional states, using body mapping and musical chord progression. Our results revealed that individuals with depressive tendencies experience strong head sensations, with unpleasantness and low aesthetics, particularly for chord progression with a high level of surprise and uncertainty. This study sheds light on the intricate relationship between music, bodily sensations, and emotional states, providing valuable insights for research on the body and for developing musical therapeutic interventions targeting depression and related conditions.

physiology↗

bioRxiv2023

Body Maps of Uncertainty and Surprise in Musical Chord Progression and its individual differences in Depression and Body Perception Sensitivity

Music has profoundly shaped the human experience across diverse cultures and generations, yet the mechanisms that it influences our minds and bodies remain elusive. This study examined how the perception of music chords elicits bodily sensations and emotions through predictive processing of the brain. By deploying body-mapping tests and emotional evaluations on 527 participants exposed to chord progressions, we unveil the intricate interplay between musical uncertainty, prediction error, and temporal dynamics in eliciting specific bodily sensations and emotions. Our results demonstrated that the chord progressions characterized by low uncertainty coupled with high surprise or predictability evoke bodily sensations closely associated with interoception including the cardiac and abdominal regions. Notably, these sensations are associated with aesthetic appreciation, with the intensity of cardiac sensations being positively correlated with valence in chord progressions with low uncertainty and high surprise. These results highlight the pivotal role of uncertainty and prediction error in shaping emotional responses and also suggest a hypothesis for emotion generation through predictive processing and sound embodiment. This study offers a tantalizing glimpse into the potential nexus between interoception by music and mental well-being, underscoring the importance of recognizing diverse forms of musical pleasure and their unique effects on our minds and bodies.

neuroscience↗

bioRxiv2023

Exploring Cognitive Individuality and the Underlying Creativity in Statistical Learning and Phase Entrainment

Statistical learning starts at an early age and is intimately linked to brain development and the emergence of individuality. Through such a long period of statistical learning, the brain updates and constructs statistical models, with the models individuality changing based on the type and degree of stimulation received. However, the detailed mechanisms underlying this process are unknown. This paper argues three main points of statistical learning, including 1) cognitive individuality based on "reliability" of prediction, 2) the construction of information "hierarchy" through chunking, and 3) the acquisition of "1-3Hz rhythm" that is essential for early language and music learning. We developed a Hierarchical Bayesian Statistical Learning (HBSL) model that takes into account both reliability and hierarchy, mimicking the statistical learning processes of the brain. Using this model, we conducted a simulation experiment to visualize the temporal dynamics of perception and production processes through statistical learning. By modulating the sensitivity to sound stimuli, we simulated three cognitive models with different reliability on bottom-up sensory stimuli relative to top-down prior prediction: hypo-sensitive, normal-sensitive, and hyper-sensitive models. We suggested that statistical learning plays a crucial role in the acquisition of 1-3 Hz rhythm. Moreover, a hyper-sensitive model quickly learned the sensory statistics but became fixated on their internal model, making it difficult to generate new information, whereas a hypo-sensitive model has lower learning efficiency but may be more likely to generate new information. Various individual characteristics may not necessarily confer an overall advantage over others, as there may be a trade-off between learning efficiency and the ease of generating new information. This study has the potential to shed light on the heterogeneous nature of statistical learning, as well as the paradoxical phenomenon in which individuals with certain cognitive traits that impede specific types of perceptual abilities exhibit superior performance in creative contexts.

neuroscience↗

bioRxiv2023

Culturally Universal Temporal Dynamics of Statistical Learning in Children's Song Contributes to Phase Entrainment and Production of Novel Information

Statistical learning is intimately linked to brain development. For example, statistical learning of language and music starts at an early age and is shown to play a significant role in acquiring the delta-band rhythm that is essential for language and music learning. However, it remains unclear how auditory cultural differences affect the statistical learning process and the resulting probabilistic and acoustic knowledge acquired through it. This study examined how childrens songs are acquired through statistical learning. This study used a Hierarchical Bayesian Statistical Learning (HBSL) model, mimicking the statistical learning processes of the brain. Using this model, we conducted a simulation experiment to visualize the temporal dynamics of perception and production processes through statistical learning among different cultures. The model learns the childrens songs (MIDI files) including English, German, Spanish, Japanese, and Korean songs as the training data. This study investigated how the model transforms the internal model over 15 trials of learning in each song. Furthermore, using the probability distribution of each model over 15 trials of learning each song, new songs were probabilistically generated. The results suggest that, in learning processes, chunking and hierarchical knowledge increased gradually through 15 rounds of statistical learning for each piece of childrens songs. In production processes, statistical learning leads to the gradual increase of delta-band rhythm (1-3 Hz). Furthermore, by combining the acquired chunks and hierarchy through statistical learning, new music can be generated gradually in comparison to the original songs (i.e., the training songs). These findings were observed consistently, irrespective of culture. The present study indicates that the innate statistical learning capacity of the brain, irrespective of cultural background, contributes to the acquisition and generation of delta-band rhythm, which is critical for acquiring language and music. It is suggested that cultural differences may not significantly modulate the statistical learning effects since statistical learning and slower rhythm processing is both essential functions in the human brain across cultures. Furthermore, statistical learning of childrens songs leads to the acquisition of hierarchical knowledge and the ability to generate novel music. This study provides a novel perspective on the developmental origins of creativity and the importance of statistical learning through early development.

neuroscience↗

bioRxiv2023

Body Maps of Sound Pitch and its individual differences in Alexithymia and Depression

Sound perception extends beyond the boundaries of auditory sensation, encompassing a profound engagement with the entire human body. This intricate interplay between sound and body sensation has long captivated the interest of researchers. In this study, we examined the relationship between our perception of sound pitch and our bodily position senses, while also exploring the role of emotions in shaping this intriguing cross-modal correspondence. We also compare the topography of pitch-triggered body sensations between depressive, alexithymia, and the control groups, and examine their associations with anxiety. Our findings reveal that individuals with depression and alexithymia experience diffuse and less localized body sensations in response to sound pitch, accompanied by heightened feelings of anxiety and negative emotions. These findings imply that diffuse bodily sensations in response to sound may trigger negative emotions such as anxiety and indicate that monitoring pitch-triggered body sensations could serve as a valuable biomarker for emotional disorders. Our study sheds light on the profound importance of body sense awareness in response to sounds, a phenomenon that may be mediated by interoception. This research enhances our understanding of the intricate relationship between sound, emotions, and the human body, offering insights for potential interventions in emotional disorders.

physiology↗

bioRxiv2022

AVP neurons act as the primary circadian pacesetter cells in vivo

The central circadian clock of the suprachiasmatic nucleus (SCN) is a network consisting of various neurons and glia. Individual cells have the autonomous molecular machinery of a cellular clock, but their intrinsic periods are considerably variable. Here, we show that arginine vasopressin (AVP) neurons set the ensemble period of the SCN network to control circadian behavior rhythm. Artificial lengthening of cellular periods by deleting casein kinase 1 delta (CK1{delta}) in the whole SCN lengthened the free-running period of behavior rhythm to an extent similar to CK1{delta} deletion specific to AVP neurons. In SCN slices, PER2::LUC reporter rhythms of these mice did not recapitulate the period lengthening. However, in vivo calcium rhythms of both AVP and vasoactive intestinal peptide (VIP) neurons demonstrated lengthened periods similar to the behavioral rhythm upon AVP neuron-specific CK1{delta} deletion. These results indicate that AVP neurons act as the primary determinant of the SCN ensemble period.

neuroscience↗

bioRxiv2022

Neural Correlates of Statistical Learning in Developmental Dyslexia: An Electroencephalography Study

The human brain extracts statistical regularities from the surrounding environment in a process referred to as statistical learning. Recent behavioural evidence suggests that developmental dyslexia affects statistical learning. However, surprisingly few neurophysiological studies have assessed how developmental dyslexia affects the neural processing underlying statistical learning. In this study, we used electroencephalography to explore the neural correlates of an important aspect of statistical learning - sensitivity to transitional probabilities - in individuals with developmental dyslexia. Adults diagnosed with developmental dyslexia (n = 17) and controls (n = 19) were exposed to a continuous stream of sound triplets in which a few triplet endings were location deviants (i.e., were presented from an unexpected speaker direction) or statistical deviants (i.e., had a low transitional probability given the triplets first two sounds). Location deviants elicited a large location mismatch negativity (MMN), which was larger in controls than dyslexics. Statistical deviants elicited a small, yet significant statistical MMN (sMMN) in controls, whereas the dyslexic individuals did not exhibit a statistical MMN. These results suggest that the neural mechanisms underlying statistical learning are impaired in developmental dyslexia. Significance statementWe assessed the neural correlates of statistical learning in individuals with developmental dyslexia. Statistical deviants, namely word endings with a low transitional probability (as compared to high probability transitions) elicited a small, yet significant statistical MMN in controls, whereas the dyslexic individuals did not exhibit a statistical MMN. Location deviants elicited a MMN, which was larger in controls than dyslexics. These results suggest that the neural mechanisms underlying statistical learning are impaired in developmental dyslexia.

neuroscience↗

bioRxiv2020

The Hierarchical Structure of Temporal Modulations in Music is Universal across Genres and matches Infant-Directed Speech.

Statistical learning by the human brain plays a core role in the development of cognitive systems like language and music. Both music and speech have structured inherent rhythms, however the acoustic sources of these rhythms are debated. Theoretically, rhythm structures in both systems may be related to a novel set of acoustic statistics embedded in the amplitude envelope, statistics originally revealed by modelling childrens nursery rhymes. Here we apply similar modelling to explore whether the amplitude modulation (AM) timescales underlying rhythm in music match those in child-directed speech (CDS). Utilising AM-driven phase hierarchy modelling previously applied to infant-directed speech (IDS), adult-directed speech (ADS) and CDS, we test whether the physical stimulus characteristics that yield speech rhythm in IDS and CDS describe rhythm in music. Two models were applied. One utilized a low-dimensional representation of the auditory signal adjusted for known mechanisms of the human cochlear, and the second utilized probabilistic amplitude demodulation, estimating the modulator (envelope) and carriers using Bayesian inference. Both models revealed a similar hierarchically-nested temporal modulation structure across Western musical genres and instruments. Core bands of AM and spectral patterning matched prior analyses of IDS and CDS, and music showed strong phase dependence between slower bands of AMs, again matching IDS and CDS. This phase dependence is critical to the perception of rhythm. Control analyses modelling other natural sounds (wind, rain, storms, rivers) did not show similar temporal modulation structures and phase dependencies. We conclude that acoustic rhythm in language and music has a shared statistical basis.

developmental biology↗