Faculty Profiles - YOKOYAMA Keiko

Papers - YOKOYAMA Keiko

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横山慶子

人工知能 Vol. 40 ( 1 ) page： 1020 - 1025 2025.1

Interpersonal strategy for controlling unpredictable opponents in soft tennis Reviewed

Yuji Yamamoto, Keiko Yokoyama, Akifumi Kijima, Motoki Okumura, and Hiroyuki Shima

Scientific Reports Vol. 14 page： 20546 2024.9

Interpersonal coordination analysis in bat-and-ball sports under a real game situation: Asymmetric interaction and delayed coupling Reviewed

R. Takamido, K. Yokoyama, H. Nakamoto, J. Ota, Y. Yamamoto

PLoS ONE Vol. 18 ( 11 ) page： e0290855 2023.11

自転車競技ポイントレース中の集団動態解析に向けた定量化 Reviewed

スポーツパフォーマンス研究 Vol. 15 page： 295 - 306 2023.7

An examination of the potential benefits of expert guided physical activity for supporting recovery from extreme social withdrawal: Two case reports focused on the treatment of Hikikomori Reviewed International coauthorship

Keiko Yokoyama, Tadaaki Furuhashi, Yuji Yamamoto, Maki Rooksby, Hamish J. McLeod

Frontiers in Psychiatry Vol. 14 ( 1084384 ) page： 1 - 14 2023.3

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

Extreme and long-term social withdrawal, first described in Japan as Hikikomori, has now become a globally recognized mental health problem. Intervention studies severely lag behind epidemiological and phenomenological research. We present two descriptive case reports of Japanese university students with Hikikomori who participated in an early phase test of a structured intervention involving physical activities that was developed and facilitated by clinicians and physical education specialists—Human Movement Consultation (HMC). The two male recipients (19 and 29-years old at the start of treatment) completed approximately 40 consultation sessions delivered over three years consisting of a combination of outdoor workouts (i.e. walking, running, and cycling) and interpersonal sports (e.g. table tennis, badminton, and tennis). Changes in social withdrawal behavior were independently rated from clinical health records using a structured scale (the Glasgow Hikikomori Scale; GHS). Behavioral observations and scale data for both cases indicated improvements from pre-treatment levels of social withdrawal. At the end of the intervention, both had returned to normative levels of functioning. Case A returned to university and Case B secured a new job and returned to the workforce. To help advance our understanding of treatment options, these case descriptions analyse potential change mechanisms in order to understand how HMC can support recovery from extreme social withdrawal. One key observation is that both outdoor workouts and interpersonal sports offer a non-threatening method of enabling Hikikomori to engage in interpersonal interactions. Such connections via structured activities may allow the reinstatement of social skills in a graded manner. In addition, an initial focus on physical experiences may help promote psychological and social connectedness without triggering the social fears and challenges that underlie the Hikikomori state. The findings from these two cases offer a framework to guide further research and the development of exercise-based interventions for this hidden and often neglected group.

DOI： https://doi.org/10.3389/fpsyt.2023.1084384

Descriptive Parameters and Its Hysteresis of the Group Separation and Recombination in Bicycle Points Races: Leader’s Velocity and Speed Difference between Leader and Main Group Reviewed

Fumihiro Okumura, Keiko Yokoyama, Yuji Yamamoto

Applied Sciences Vol. 13 ( 3 ) page： 1315 - 1315 2023.2

Language：English Publishing type：Research paper (scientific journal) Publisher：MDPI AG

This study examined the descriptive parameters for separation and recombination processes in a cycling points race. The candidate descriptive parameters were the speed of the leading cyclist and the main group and the difference between their time and speed. We focused on the transition between the four states of peloton configuration (dense state, stretched state, divided state, and escape and dense state) defined by previous studies that occur during the points race. As a result, it was found that the distribution of the leader’s velocity and the speed difference significantly differed when the groups were separated and recombined compared to when the state did not change. It was also examined whether the separation and recombination processes had a phenomenon such as a hysteresis depending on the present state. Regarding the leader velocity and the speed difference between the leader and the main group, the state of the group was not uniquely determined by the speed difference, and the influence of the speed difference for separation or recombination depended on the state; that is, there was asymmetry in separation and recombination in a points race. These suggest that the cyclists need the ability to choose an appropriate speed and distance from other cyclists depending on the situation.

DOI： 10.3390/app13031315

Web of Science

The Influence of Shared Intentions With Others in Physical and Cognitive Tasks That Require Collaborative Solving in Elementary School Reviewed

Takahiro Kano, Keiko Yokoyama, Yuji Yamamoto

Frontiers in Education Vol. 7 2022.6

Language：English Publishing type：Research paper (scientific journal) Publisher：Frontiers Media SA

Developing the competence to share intentions with others is an important role of elementary schools for the children’s future well-being. We analyzed and clarified the relationship between physical and cognitive tasks that require collaborative solving to cultivate the skill of sharing intentions with others through human movement. As a physical task, we designed a tag game in which two defenders prevented three attackers from passing through to reach the goal line. We focused on the defenders’ movement in the game and analyzed the efficiency of each defender’s movement as an individual behavior and the interpersonal distance between these two defenders as a pair behavior. As a cognitive task, we examined pair activities when understanding concepts in math classes. We observed talking and listening behaviors during the pair activities and analyzed the responsive behavior as an individual behavior, which comprised responsive utterances and active listening from the listener’s gaze direction. Role change during pair activities in math lessons was analyzed as a pair behavior. We then analyzed the relationship between behaviors in both tasks. The hypotheses were as follows: (1) task constraints lead to an interaction between individual and pair behaviors in both tasks and (2) individual and pair behaviors in the two tasks have similar characteristics. The results from both tasks support the first hypothesis that the efficiencies of individual movement and interpersonal distance in the tag game and the frequencies of responsive behavior and role changes in the pair activities in math classes are positively correlated. The results also support the second hypothesis that the individual and pair behaviors in the two tasks are significantly correlated. These results suggest that the competence to share intention with others is fundamental regardless of the task nature: physical or cognitive. The findings suggest that the task constraints of joint action in physical education lead to an understanding of the task goals and to exploring the solution for winning. These experiences might be generalized to all cognitive tasks for cultivating the competence to share intentions with others.

DOI： 10.3389/feduc.2022.863267

Web of Science

Hitting movement patterns organized by different pitching movement speeds as advanced kinematic information Reviewed

Ryota Takamido, Keiko Yokoyama, Yuji Yamamoto

Human Movement Science Vol. 81 2022.2

Effect of Manipulating Advanced Kinematic Information on Hitting Movement Prediction, Perception, and Action. Reviewed International journal

Ryota Takamido, Keiko Yokoyama, Yuji Yamamoto

Research quarterly for exercise and sport Vol. 92 ( 4 ) page： 747 - 759 2021.10

Language：English Publishing type：Research paper (scientific journal)

Purpose: This study examined the effect of manipulating advanced kinematic information about opponents' pitching movement on ball speed prediction, ball speed perception, and impact timing errors under strict temporal constraints (i.e., a softball game). Method: Three experiments were conducted using visual stimuli consisting of varied kinematic information-different pitching movements with the same ball trajectory. In Experiment 1, participants observed the pitching movement of the visual stimuli and predicted pitched ball speed as a two-interval forced choice discrimination task (2IFC). In Experiment 2, participants observed both the pitching movement and ball trajectory, and evaluated the pitched ball speed as a 2IFC. In Experiments 3a and 3b, they tried to swing against the pitched ball presented on the screen as accurately as possible with regard to timing. Results: Batters tended to predict the ball was moving faster when the pitching movement was faster (Experiment 1). Incorrectly predicting the ball speed due to the difference in advanced kinematic information also biased batters' perception of the speed (Experiment 2), and this biased prediction yielded congruent impact timing (Experiment 3a). The impact timing error of naive participants also was affected by kinematic information (Experiment 3b). Conclusion: Limitations of this study (representative task design, sample size, and experimental procedures) notwithstanding, results indicate that, under strict temporal constraints, batters' perceptions and actions are sensitive to advanced kinematic information, which could lead to biased perceptions and actions.

DOI： 10.1080/02701367.2020.1773375

Web of Science

PubMed

State transitions among groups of cyclists in cycling points races Reviewed

Fumihiro Okumura and Keiko Yokoyama and Yuji Yamamoto

Vol. Published online 2021.3

How Training Tools Physically Linking Soccer Players Improve Interpersonal Coordination Reviewed International coauthorship International journal

Keiko Yokoyama, Noriyuki Tabuchi, Duarte Araujo, Yuji Yamamoto

JOURNAL OF SPORTS SCIENCE AND MEDICINE Vol. 19 ( 2 ) page： 245 - 255 2020.6

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：JOURNAL SPORTS SCIENCE & MEDICINE

Interpersonal coordination is an important skill for promoting collective behavior in team sports. This study tested the impact of two types of tools in facilitating triadic coordination. 16 males aged under 12 years were divided into four groups with similar skill levels and average ages. Each group performed a three-versus-one ball passing task under three conditions: a one-elasticband tool linking the three players, a three-elastic-bands tool linking the three players, and without a tool linking the three players. The dependent variables were ball passing frequency, frequency and amplitude of inner angles of the triangle formed by the players, and duration of the synchronized patterns of the inner angles. The results show that neither tool increased ball-passing frequency or the duration of synchronized patterns. However, both tools increased the frequency of inner angles, and the three-elastic-bands tool decreased the amplitude of inner angles. From these results, we conclude that elastic-band tools affect spatial and temporal triadic formation by means of haptic and visual information. Specifically, compared with the one-elastic-band tool, the three-elastic-bands tool stabilizes the triadic spatial formation. We also explore the implications for how these tools can be used in practice.

Web of Science

連携技能に関わる練習道具のトレーニング効果を検証する Reviewed

横山慶子, 田渕規之，山本裕二

スポーツパフォーマンス研究 Vol. 12 page： 193 - 208 2020.4

集団運動における協調スキルを評価する Invited

体育の科学 Vol. 70 ( 3 ) page： 203-207 2020.3

Task constraints and stepping movement of fast-pitch softball hitting Reviewed

Ryota Takamido, Keiko Yokoyama, Yuji Yamamoto

PLoS ONE Vol. 14 ( 2 ) page： e0212997 2019.2

Language：English Publishing type：Research paper (scientific journal)

This study aims to clarify the relationship between task constraints and the preparatory movement of fast-pitch softball batters in Japan for three different competition categories, namely high school, college, and league. As task constraints, we focused on the temporal and tool constraints and evaluated preparatory movements using initiation time and step duration of the stepping movement in a striking action. First, we confirmed the temporal constraints in each category and then examined the relationship between the temporal constraints and the stepping movements. The results demonstrated that the temporal constraints affected both initiation time and step duration of the stepping movements. Hierarchical cluster analysis was applied to the two variables. Consequently, the stepping movement of the softball players was classified into three types: “late initiation–short duration” (LS), “early initiation–short duration” (ES), and “early initiation–long duration” (EL) corresponding to the task constraints. Finally, the relationship between the task constraints of each category and the stepping movements was examined. The results revealed that high school players exhibited mostly the LS- or EL-type stepping movement; college players exhibited mostly the EL-type stepping movement; and league players exhibited all types. These results depict that the players in each category with each temporal and tool constraint exhibited particular types of stepping movements as a preparatory movement corresponding to each task constraint, thereby arguing that players use a not-to-lose strategy exploiting the redundancy in solutions under various task constraints.

DOI： 10.1371/journal.pone.0212997

Web of Science

Scopus

PubMed

A Switching Hybrid Dynamical System: Toward Understanding Complex Interpersonal Behavior Reviewed

Yamamoto. Y, Kijima., A, Okumura., M, Yokoyama., K, Gohara., K

Appl. Sci. Vol. 9 ( 1 ) page： 1 - 15 2019.1

Motor control of practice and actual strokes by professional and amateur golfers differ but feature a distance-dependent control strategy. Reviewed International journal

Yumiko Hasegawa, Keisuke Fujii, Akito Miura, Keiko Yokoyama, Yuji Yamamoto

European journal of sport science Vol. 19 ( 9 ) page： 1204 - 1213 2019

Language：Japanese Publishing type：Research paper (scientific journal)

We explored how practice and actual putting strokes differed between professionals and high-level golf amateurs, and how practice strokes reflected subtle differences in putting distances. We analysed swing amplitude, impact velocity, and acceleration profile of the club-head. The acceleration profiles showed that the motor control pattern of the practice stroke differed from that of the actual stroke. To clarify the effects of different putting distances on the practice stroke and to analyse how much the actual stroke could be explained by the practice stroke, we conducted individual regression analyses. The practice strokes of all participants could be divided into three strategies and five types by the coefficient of determination and the slope. This implies that the purpose of the practice stroke varied among golfers. Most golfers used the individual velocity criteria in their practice strokes, which resulted in different putting distances based on their criteria. Unexpectedly, we found no significant difference in skill level between professionals and high-level amateurs. The results of this study imply that the practice stroke does not duplicate the actual stroke, even for professional golfers with excellent skills. However, most high-level golfers adopted distance-dependent control strategies for slightly different putting distances.

DOI： 10.1080/17461391.2019.1595159

Web of Science

PubMed

Social forces for team coordination in ball possession game Reviewed

Keiko Yokoyama, Hiroyuki Shima, Keisuke Fujii, Noriyuki Tabuchi, Yuji Yamamoto

Physical Review E Vol. 97 ( 2 ) 2018.2

Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：American Physical Society

Team coordination is a basic human behavioral trait observed in many real-life communities. To promote teamwork, it is important to cultivate social skills that elicit team coordination. In the present work, we consider which social skills are indispensable for individuals performing a ball possession game in soccer. We develop a simple social force model that describes the synchronized motion of offensive players. Comparing the simulation results with experimental observations, we uncovered that the cooperative social force, a measure of perception skill, has the most important role in reproducing the harmonized collective motion of experienced players in the task. We further developed an experimental tool that facilitates real players' perceptions of interpersonal distance, revealing that the tool improves novice players' motions as if the cooperative social force were imposed.

DOI： 10.1103/PhysRevE.97.022410

Web of Science

Scopus

集団スポーツにおける協調と共感（Coordination and sympathy in collective sports）

横山慶子

日本体育学会大会予稿集 Vol. 69 ( 0 ) page： 37_1 - 37_1 2018

Language：Japanese Publisher：一般社団法人日本体育学会

<p>　集団スポーツでは、チーム内のプレイヤー間の協調した動きが必要とされる。協調が上手く機能すれば、個人の能力の総和以上の結果が、チームとして発揮される場合があるが、上手く機能しなければその逆も有り得る。プレイヤーは、複数の他者のコート上での位置や動きを敏感に察知して他者の意図に共感し、状況に応じて最適な動きを実行しなければならない。熟練したチームの華麗なパスワークなどをみると、まるで彼らは見えない糸で繋がったひとつの生命体のようである。我々は、こうした洗練されたチームの協調を実現するためには、個人のプレイヤーがどのような情報を察知して動く必要があるのかを検証するために、社会行動の数理モデル（Social force model）に注目した。このモデルは、混雑した人混みにおいて、歩行者が他者や障害物との衝突を回避する際に働く「見えない力」を定式化したもので、群集の避難行動のシミュレーションなどに応用されている。本シンポジウムでは、この数理モデルを援用して、サッカーの3対1課題を行う3者の協調した動きを3種類の「見えない力」で再現した結果を紹介し、集団スポーツにおける協調と共感について考えてみたい。</p>

DOI： 10.20693/jspehss.69.37_1

CiNii Research

身体運動相談：ひきこもり学生支援の新たな試み

横山慶子・古橋忠晃・山本裕二

名古屋大学学生相談総合センター紀要 Vol. 17 page： 36-41 2017

Resilient help to switch and overlap hierarchical subsystems in a small human group Reviewed

K. Fujii, K. Yokoyama, T. Koyama, A. Rikukawa, H. Yamada, Y. Yamamoto.

Scientific Reports Vol. 6 page： 23991 2016.4

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Papers - YOKOYAMA Keiko