Itaguchi, Yoshihiro

写真a

Affiliation

Faculty of Letters, Department of Humanities and Social Science (Human Relations) ( Mita )

Position

Associate Professor
Scopus Paper Info  
Paper Count: 29 Citation Count: 204 h-index: 8

Click to view the Scopus page. The data was downloaded from Scopus API in March 29, 2026, via http://api.elsevier.com and http://www.scopus.com .

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Papers 【 Display / hide 】

  • Unconscious cultural cognitive biases in explicit processes of visuomotor adaptation

    Yamada C., Itaguchi Y., Rodríguez-Aranda C.

    Npj Science of Learning 10 ( 1 )  2025.12

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    Studies have shown that explicit strategies make a significant contribution to visuomotor adaptation. However, little attention has been given to potential unconscious cognitive biases in these strategies, despite that they involve a sequence of cognitive decision-making processes. To reveal the possible cultural biases involved in motor learning, we compared Norwegian and Japanese participants in a visuomotor adaptation task using a verbal report paradigm. The results showed that Japanese participants aimed at locations more deviant from the target to account for rotated visual feedback. Additionally, a greater proportion of Japanese participants changed their aiming direction more frequently than Norwegian participants, even after successfully hitting the target. However, both groups showed similar behavioral performance, with comparable reaching accuracy and aftereffect amplitudes. These results suggest that the explicit component, which is estimated based on verbal reports, includes cognitive biases. The present study challenges the assumption of universality of motor learning among cultures.

  • A Japanese LDA model for automatic clustering analysis of semantic verbal fluency tests

    Yoshihara M., Itaguchi Y.

    Behavior Research Methods 57 ( 8 )  2025.08

    ISSN  1554351X

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    In the semantic variant of verbal fluency tests (VFTs), clustering analysis has become popular for examining the semantic structure. While the computational psycholinguistics approach has recently drawn attention to increasing the reproducibility of clustering analysis, such an approach is not available in all languages. To make the computational approach available in the Japanese language, we constructed a Japanese latent Dirichlet allocation (LDA) model. Our LDA model enables researchers and clinicians to objectively quantify the associative relationships of words, thereby making it possible to automatically detect semantic clusters. We conducted the semantic VFT with healthy young Japanese adults to examine the validity of our LDA model. We performed clustering analyses using the computational approach with our LDA model and the conventional manual approach with human coders. The results showed that the LDA model identified semantic clusters, as did the human coders. In addition, we demonstrated for the first time that response intervals within a cluster were significantly shorter than those outside of clusters, regardless of the clustering approaches. This indicates that both approaches reflect a broadly accepted assumption that closer semantic relations require less processing time. However, LDA-based clustering produced, on average, larger clusters than human-based clustering did, indicating that the LDA model captured semantic relationships between words that human coders would not recognize. Taken together, the present results demonstrated the validity of our LDA model. We hope that our LDA model fosters the use of the computational linguistic approach in semantic VFTs with Japanese participants.

  • Understanding the semantic organization of animal fluency in mild Alzheimer's disease through time-course analysis and LDA topic modelling

    Itaguchi Y., Waterloo K., Johnsen S.H., Rodríguez-Aranda C.

    Neuropsychologia 211 2025.05

    ISSN  00283932

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    Deterioration of semantic memory represents an important feature of Alzheimer's disease (AD), which has been widely addressed in neuropsychological research. A way to understand semantic integrity in AD patients is through a detailed analysis of verbal fluency (VF) performance. In the present study, we used an innovative methodology that combines measures of between-words latencies together with automatized identification of semantic clusters via Latent Dirichlet Analysis (LDA) to acquire a more precise understanding of the dynamics and semantic organization of VF in patients at early stages of AD. Importantly, and diverging from customary procedures, we included VF errors (i.e., repetitions and intrusions) across analyses. For comparison, a group of healthy older adults and young individuals were also examined. Standard parameters including total correct answers, number of clusters, mean cluster size (MCS), cluster duration, and within and out-of-cluster intervals were calculated. These parameters were expressed as mean values in 1-min VF trials and by calculating mean values in four 15-s time windows. Results for the 1-min trial demonstrated significantly larger mean cluster sizes (MCS) and fewer generated answers in AD patients compared to the healthy groups. No additional group differences were found neither on time intervals (both within and out-of-clusters), nor on the 15-s time windows analyses. These data suggest that the clustering ability of mild AD patients might be affected by executive impairments promoting larger MCS. At the same time, we found similar semantic processes and timings in patients and healthy participants. The main difference resides in the structure of the patients' clusters, which encompassed erroneous answers. We advance the idea that production of errors might not only be a consequence of executive dysfunction or working memory deterioration, but also a sign that associative semantic mechanisms are still active early in the disease, despite an evident loss of information.

  • Effects of within-day intervals on adaptation to visually induced motion sickness in a virtual-reality motorcycling simulator

    Kasegawa C., Itaguchi Y., Yamawaki Y., Miki M., Hayashi M., Miyazaki M.

    Scientific Reports 14 ( 1 )  2024.12

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    This study investigated the effects of the time interval between virtual reality (VR) sessions on visually induced motion sickness (VIMS) reduction to better understand adaptation to and recovery from a nauseating VR experience. The participants experienced two 6-min VR sessions of a first-person motorcycle ride through a head-mounted display with (1) a 6-min interval, (2) an interval until the VIMS score reached zero, and (3) a 60-min interval. The results showed that for each condition, VIMS in the second session was aggravated, unchanged, or attenuated, respectively, indicating that additional resting time was necessary for VIMS adaptation. This study suggests that a certain type of multisensory learning attenuates VIMS symptoms within a relatively short time, requiring at least 20 min of additional resting time after subjective recovery from VIMS symptoms. This finding has important implications for reducing the time interval between repeated challenges when adapting to nauseating stimuli during VR experiences.

  • Breathing signatures of semantic and phonemic verbal fluency and their impact on test performance in a sample of young Norwegian adults

    Gullsvåg M., Itaguchi Y., Rodríguez-Aranda C.

    Plos One 19 ( 12 December )  2024.12

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    Verbal fluency (VF) represents an important aspect of intelligence, in which oral word generation is demanded following semantic or phonemic cues. Two reliable phenomena of VF execution have been reported: A decay in performance across 1-minute trial and a discrepancy score between the semantic and phonemic VF tests (VFTs). Although, these characteristics have been explained from various cognitive standpoints, the fundamental role of speech breathing has not yet been considered. Therefore, the present study aims to evaluate the role of respiratory function for word generation in VFTs in healthy individuals. Thirty healthy young adults performed VFTs during definite periods of 1 minute while wearing a pneumotachograph mask. Duration, peak and volume of airflow were acquired during inspirations and expirations. Also, respiratory rate and acoustic data of verbal responses were registered, and accuracy scores were calculated. Each 1-minute trial was divided into four intervals of 15-seconds where parameters were calculated. Repeated measures ANOVAs and repeated measures correlations were used in the statistical analyses. Data revealed that respiratory function was significantly coupled to VF performance mostly during inhalations. Small but constant increments of inhale airflow occurred in phonemic VFT as well as higher peak airflow in both tasks, being higher for semantic VFT. High respiratory rate characterized performance of both VFTs across intervals. Airflow adjustments corresponded to better VF accuracy, while increments in respiratory rate did not. The present study shows a complex interplay of breathing needs during VF performance that varies along the performance period and that notably connects to inspirations.

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Papers, etc., Registered in KOARA 【 Display / hide 】

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

  • The continuum of body, tools, and pathological states: "self" system based on perception and movement

    2024.04
    -
    2028.03

    基盤研究(B), Principal investigator

  • 脳損傷と加齢が潜在意味構造に与える影響の解明：自然言語処理に基づいたアプローチ

    2020.07
    -
    2023.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Challenging Research (Exploratory), Principal investigator

  • ヒト身体における仮想的運動神経支配入れ替えが引き起こす適応的可塑性の解明

    2020.04
    -
    2024.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Principal investigator

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Courses Taught 【 Display / hide 】

  • SEMINAR IN COGNITIVE PSYCHOLOGY 4

    2025

  • SEMINAR IN COGNITIVE PSYCHOLOGY 3

    2025

  • RESEARCH METHODS OF PSYCHOLOGY

    2025

  • PSYCHOLOGY 2

    2025

  • PSYCHOLOGY 1

    2025

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