Ryoko TAKIKAWA, Ph.D.

1. Apr, 2025 - Present

Research fellow, Japan Advanced Institute of Science and Technology 

2. Apr, 2025 - Present

Invited Researcher, Research Institute for Letters, Arts and Sciences, Waseda University 

3. Apr, 2025 - Present

Lecturer (part-time), Waseda University 

4. Apr, 2024 - Mar, 2025

Assistant Professor, Faculty of Letters, Arts and Sciences, Waseda University 

5. Apr, 2024 - Mar, 2025

Lecturer (part-time), J. F. Oberlin University 

6. Apr, 2023 - Mar, 2025

Lecturer (part-time), Breau of Social Welfare and Public Health, Tokyo Metropolitan Government 

7. Apr, 2023 - Mar, 2024

Research Associate, Faculty of Letters, Arts and Sciences, Waseda University 

8. Apr, 2017 - Mar, 2020

JSPS Research Fellowship for Young Scientists, Japan Society for the Promotion of Science 

9. Apr, 2016 - Mar, 2018

Researcher of Long-term longitudinal health and longevity research (SONIC), Tokyo Metropolitan Institute for Geriatrics and Gerontology 

10. May, 2016 - May, 2016

Lecturer (part-time), Department of Rehabilitation, Tamagawa Hospital 

1. Apr, 2018 - Feb, 2024

Graduate School of Letters, Arts and Sciences, Waseda University 

1. Nov, 2025 - Present

Committee member, The Japanese Psychological Association Committee on International Affairs 

2. Nov, 2025 - Present

Committee member, The Japanese Psychological Association International Prize Selection Committee 

3. Mar, 2025 - Present

The 3rd "Survey on the Status of Gender Equality among Researchers in the Humanities and Social Sciences" Committee member, Gender Equality Association for Humanities and Social Sciences (GEAHSS) 

4. Mar, 2025 - Present

Delegate, Japanese Psychological Association 

5. Jun, 2022 - Present

 Manager, Japanese Psychological Association Early Career Psychologists Network 

6. Jun, 2024 - Nov, 2024

Manager, The 15th multisense research society 

7. Jun, 2022 - Jun, 2023

Manager, The workshop of the Japanese Psychological Association Early Career Psychologists Network 2023, The Japanese Psychological Association Early Career Psychologists Network 

1. Jun, 2022Jun, 2022

The 2022 HBES Best Poster award, Telomeres moderate the influence of testosterone on mating behavior of men, The 33rd annual conference of the Human Behavior and Evolution Society 

Ryoko Takikawa, Yasuyuki Fukukawa

2. Mar, 2017

Outstanding Master's Thesis, Waseda University Graduate School, Graduate School of Letters, Arts and Sciences, Waseda University 

Ryoko Takikawa

1. The influence of familial nudging on attitudes toward climate change and monetary contributions: An exploration of ease and difficulty with evidence from Japan, Canada, the USA, and Norway

Hidenori Komatsu, Hiromi Kubota, Kenji Asano, Yu Nagai, Catherine Salmon, David Widman, Elisabeth Oberzaucher, T. Joel Wade, Leif Edward Ottesen Kennair, Maryanne L. Fisher, Rebecca Burch, Ryoko Takikawa, Samara Rice

Sustainable Futures, 2025  Peer-reviewed 

2. Sex differences in birth weight depending on the mother's condition: Testing the Trivers-Willard hypothesis in Indian twins
   Ryoko Takikawa, Yasuyuki Fukukawa
   Evolution and Human Behavior, 45(1) 41-47, Feb, 2024  Peer-reviewed   Lead author   Corresponding author  

3. Testing gender differences: The dark triad and motives for deceptive impression management
   Ryoko Takikawa, Yasuyuki Fukukawa
   Social Behavior and Personality: an international journal, 51(6) 1-11, Jun 20, 2023  Peer-reviewed   Lead author   Corresponding author  

4. Fundamental study of movement sensation related to physical functions: Psychophysiological research using chaotic interactions of biosignals

Ryoko Takikawa

Waseda University Graduate School of Letters, Arts and Sciences Bulletin, 63(18) 61-65, Mar, 2018  Peer-reviewed   Lead author   Corresponding author  

5. Promoting bilateral symmetry in the body through an eastern medical approach examining the chaotic nature of pulse waves using a neck rotation task via Sotai therapy
   Ryoko Takikawa, Yasutomo Ishii
   International Journal of Electronics and Communication Engineering and Technology, 7(3) 130-141, 2016  Peer-reviewed   Lead author   Corresponding author  

6. The impact of trait anxiety under a painful stimulus on the chaotic synchronization of respiration and pulse waves
   Ryoko Takikawa, Yasutomo Ishii, Taira Suzuki, Mayumi Oyama-Higa
   Journal of Information and Communication Engineering, 1(1) 1-8, Nov, 2015  Peer-reviewed   Lead author   Corresponding author  

7. Chaotic synchronization of respiration and center of gravity sway
   Ryoko Takikawa, Yasutomo Ishii, Taira Suzuki, Mayumi Oyama-Higa
   Journal of Bioinformatics and Neuroscience, 1(1) 1-7, Nov, 2015  Peer-reviewed   Lead author   Corresponding author  

8. Chaotic synchronization of pulse waves and respiration
   Ryoko Takikawa, Yasutomo Ishii, Taira Suzuki, Mayumi Oyama-Higa
   Journal of Bioinformatics and Neuroscience, 1(1) 24-30, Nov, 2015  Peer-reviewed   Lead author   Corresponding author  

1. PSYCHOLOGY WORLD 111 

Ryoko Takikawa (Role: Contributor, Progress report of Mama Ph.D.)

The Japanese Psychological Association, Nov, 2025

2. Cognitive science of religion 

Ryoko Takikawa (Role: Contributor, Life History)

Shinyo-sya,Ltd., 2025

3. The book to read if you want to study psychology at university: An invitation to the science of the mind  
   (Role: Contributor, Strategic Mom: Evolutionary Psychology of Female)
   Seishin Shobo, Ltd., 2024

4. PSYCHOLOGY WORLD 101
   Ryoko Takikawa (Role: Contributor, Evolutionary psychology: Mating strategy)
   The Japanese Psychological Association, Apr, 2023

5. PSYCHOLOGY WORLD 100
   Ryoko Takikawa (Role: Contributor, Mama Ph.D.)
   The Japanese Psychological Association, Jan, 2023

1. The influence of mismatch between paternal telomere length and maternally derived mtDNA polymorphism on the relationship between testosterone and male mating behavior and sexual function 

Ryoko Takikawa, Yo Nakawake

The 18th annual conference of the Human Behavior and Evolution Society of Japan, Nov, 2025

2. An exploratory study of factors influencing attitudes toward wild animals: The psychological basis of urban bear protection and elimination 

Yoko Nagai, Ryoko Takikawa, Yo Nakawake

The 66th Annual Conference of the Japanese Society of Social Psychology, Sep, 2025

3. Encouraging International Collaborative Research: How to Get Started?
   Committee on International, Affairs JPA, Ryoko Takikawa, Momoka Sunohara, Yuka Ozaki, Mohsen Joshanloo, Igor de Almeida, Yuki Shimizu, Yuri Miyamoto, Saori Tsukamoto, Joonha Park
   The 89th annual convention of the Japanese Psychological Association, Sep, 2025

4. The roundtable for sharing worries of early career psychologists and networking in the field, The Annual Conference of the Japanese Psychological Association Symposium
   Sayaka Kawakami, Kazuya Inoue, Daisuke Kydo, Toshiko Sato, Ryoko Takikawa
   The 89th annual convention of the Japanese Psychological Association, Sep, 2025

5. One-shot presentation for early career psychologists, The Annual Conference of the Japanese Psychological Association Symposium
   Daisuke Kudo, Ryoko Takikawa, Sayaka Kawakami
   The 89th annual convention of the Japanese Psychological Association, Sep, 2025

6. Messenger profiles rooted in mating efforts supercharge nudging effects to promote environmental protection 

Hidenori Komatsu, Leif Edward Ottesen Kennair, Maryanne L.Fisher, Mackenzie Zinck, Nobuyuki Tanaka, Ryoko Takikawa

The 36th Annual Human Behavior & Evolution Society Conference, Jun, 2025

7. Andrology 2025 Testosterone and Genomic Medicine The effect of telomere length on the relationship between male mating behavior and testosterone: An evolutionary psychological study on the reproductive strategy of human males
   Ryoko Takikawa
   The 25th Annual Meeting of the Japanese Society of Anti-Aging Medicine, Jun, 2025  Invited 

8. Interaction effects of life history strategy and the cue for resources on the receptiveness of new technologies
   Ryoko Takikawa, Catherine Salmon, David Widman, Hidenori Komatsu, Leif Edwar, Ottesen Kennair, Maryanne L. Fisher, Mackenzie Zinck, Nobuyuki Tanaka, T. Joel Wade
   The 36th Annual Human Behavior and Evolution Society Conference, Jun, 2025

9. One-shot presentation for early career psychologists, The Annual Conference of the Japanese Psychological Association Symposium
   Daisuke Kudo, Tomoki Maezawa, Ryoko Takikawa, Sayaka Kawakami
   The 88th annual convention of the Japanese Psychological Association, Sep, 2024

10. Supporting the internationalization of students and young researchers: The current state and future of support measures in the Japanese Psychological Association
    Tsuneyuki Abe, Yuka Ozaki, Li Yan, Ryoko Takikawa, Yukiko Goda, Yuki Murai
    The 88th annual convention of the Japanese Psychological Association, Sep, 2024  Invited 

11. Stress sensitivity moderates the influence of birth weight on the timing of puberty
    Ryoko Takikawa
    33rd International Congress of Psychology, Jul, 2024

12. Stress sensitivity moderates the influence of birth weight on age at menarche: The examination of Japanese women's timing of puberty 

Ryoko Takikawa

The 35th annual conference of the Human Behavior and Evolution Society, May, 2024

13. The relationships of chronotype with BMI and cognitive performance among university students 

Yasuyuki Fukukawa, Ryoko Takikawa

16th European Public Health Conference 2023 Nov, 2023

14. Work-life balance for researchers
    Ryoko Takikawa, Kengo Yokomitsu, Daisuke Kudo, Tetsuo Sato, Tomoki Maezawa
    The workshop of the Japanese Psychological Association Early Career Psychologists Network 2023, Jun, 2023  Invited 

15. How to become JSPS Research Fellowship for Young Scientists

Ryoko Takikawa, Kenta Tomita, Tomoki Maezawa
The workshop of the Japanese Psychological Association Early Career Psychologists Network 2023, Jun, 2023  Invited   Invited

16. The effect of male telomere length on the relation between testosterone and mating behavior
    Ryoko Takikawa, Yasuyuki Fukukawa
    the IAGG Asia/Oceania Regional Congress 2023, Jun, 2023

17. Is the behavioral immune system human universal?: An international comparison between Malaysia and the Philippines
    Ryoko Takikawa, Yasuyuki Fukukawa, Guadalupe Salanga, M, Tan Soon-Aun
    The 34th annual conference of the Human Behavior and Evolution Society, Jun, 2023

18. The Relationship between conception risk across the menstrual cycle and altruistic behavior
    Ryoko Takikawa, Yasuyuki Fukukawa
    The 14th Asian Conference on the Social Sciences, May, 2023

19. Women's interpersonal attitudes depend on conception risk
    Ryoko Takikawa, Yasuyuki Fukukawa
    The 13th Asian Conference on Psychology & Behavioral Sciences, Apr, 2023

20. Updating academic conferences: A symposium by the Japanese Psychological Association (YouTube Live)
    Kosuke Sawa, Masataka Higuchi, Tsuneyuki Abe, Ryoko Takikawa, Shunsaku Nakayama, Shinichi Tagami, Ryo Karasawa

The Japanese Psychological Association, Mar, 2023  Invited 

21. Just world beliefs moderate the influence of autobiographical memory on anxiety
    Ryoko Takikawa, Yasuyuki Fukukawa
    The 2023 annual conference of the Society for Personality and Social Psychology Religion and Spirituality preconference, Feb, 2023

22. Are there cultural differences in the relationship between behavioral immunity and food preferences? 

Yasuyuki Fukukawa, Ryoko Takikawa, Salanga M. Guadalupe, Soon-Aun Tan

The 15th annual conference of the Human Behavior and Evolution Society of Japan, Dec, 2022

23. Testing the Trivers-Willard hypothesis using birth weight ratios of opposite-sex twins 

Ryoko Takikawa, Yasuyuki Fukukawa

The 15th annual conference of the Human Behavior and Evolution Society of Japan, Dec, 2022

24. Just world beliefs moderate the influence of autobiographical memory on anxiety
    Ryoko Takikawa, Yasuyuki Fukukawa
    Sep, 2022

25. Telomeres moderate the influence of testosterone on mating behavior of men
    Ryoko Takikawa, Yasuyuki Fukukawa
    The 33rd annual conference of the Human Behavior and Evolution Society, Jun, 2022

26. The effect of birth weight on age at menarche: Considering stress responsiveness
    Ryoko Takikawa, Yasuyuki Fukukawa
    The 14th annual conference of the Human Behavior and Evolution Society of Japan, Dec, 2021

27. Sex differences in birth weight by maternal age: Testing the Trivers-Willard hypothesis in Indian twins
    Ryoko Takikawa, Yasuyuki Fukukawa
    The 85th annual convention of the Japanese Psychological Association, Sep 1, 2021

28. The effect of dark triad on acting in daily life and self-contradiction
    Ryoko Nojiri (Takikawa), Yasuyuki Fukukawa
    Association for Research in Personality 7th Biennial Conference, Jul, 2021

29. Promoting bilateral symmetry in the body through an eastern medical approach
    Ryoko Takikawa, Yasutomo Ishii

7th Society for Tokyo Young Psychologists, Mar, 2017

30. Promoting symmetry of the human body by Eastern medicinal approach: A psychophysical study using head-turning tasks
    Ryoko Takikawa, Yasutomo Ishii
    31st International Congress of Psychology (ICP2016), Jul, 2016

31. The impact of trait anxiety under a painful stimulus on the chaotic synchronization of respiration and pulse waves
    Ryoko Takikawa, Yasutomo Ishii, Taira Suzuki, Mayumi Oyama-Higa
    2015 International Conference on Intelligent Informatics and Biomedical Sciences (ICIIBMS), Nov, 2015

32. Chaotic synchronization of respiration and center of gravity sway
    Ryoko Takikawa, Yasutomo Ishii, Taira Suzuki, Mayumi Oyama-Higa
    2015 International Conference on Intelligent Informatics and Biomedical Sciences (ICIIBMS), Nov, 2015

33. Chaotic synchronization of pulse waves and respiration
    Ryoko Takikawa, Yasutomo Ishii, Taira Suzuki, Mayumi Oyama-Higa
    2015 International Conference on Intelligent Informatics and Biomedical Sciences (ICIIBMS), Nov, 2015

34. Chaotic synchronization of biological information: Coupling between respiration and pulse wave
    Ryoko Takikawa, Taira Suzuki, Yasutomo Ishii, Mayumi Oyama-Higa
    The 79th annual convention of the Japanese Psychological Association, Sep, 2015

35. Examination of the effect of family size on the frequency of three-character kanji compounds
    Rikuta Mizukoshi, Masahiro Yoshihara, Junyi Xue, Keisuke Ida, Yuma Matsuki, Ryoko Takikawa, Yasushi Hino
    The 18th annual meeting of Cognitive Neuropsychology Society, Aug, 2015

36. 26. Psychophysiological changes under painful stimulation: An experimental study using chaos analysis of fingertip pulse waves
    Ryoko Takikawa, Taira Suzuki

1. Apr, 2025 - Present

Practical psychology experiment 3AB  (Waseda University) 

2. Apr, 2025 - Present

Practical psychology experiment 1AB  (Waseda University) 

3. Sep, 2024 - Mar, 2025

Practical psychology experiment  (J. F. Oberlin University) 

4. Apr, 2024 - Mar, 2025

Psychology experiment  (J. F. Oberlin University) 

5. Apr, 2023 - Mar, 2025

Basic lecture 6  (Waseda University) 

6. Apr, 2023 - Mar, 2025

Basic lecture 5  (Waseda University) 

7. Apr, 2023 - Mar, 2025

Family sociology  (Breau of Social Welfare and Public Health, Tokyo Metropolitan Government) 

8. May, 2016 - May, 2016

Research and Statistics Method  (Tamagawa Hospital) 

1. Jun, 2025 - Present

The Japanese Society of Social Psychology 

2. Jun, 2025 - Present

Japanese Society of Anti-Aging Medicine 

3. Dec, 2022 - Present

The Society for Personality and Social Psychology 

4. Jun, 2022 - Present

The Human Behavior and Evolution Society 

5. Nov, 2021 - Present

The Human Behavior and Evolution Society of Japan 

6. Apr, 2014 - Present

The Japanese Psychological Association 

1. Elucidating the evolutionary origins and psychophysiological responses of prejudice
   Grant-in-Aid for Early-Career Scientists, Japan Society for the Promotion of Science, Apr, 2025 - Mar, 2028
   Ryoko Takikawa

2. Lifestyle measures that simultaneously promote low-carbon society and an increase in the number of births
   Carbon Recycling Fund Research Grant, Carbon Recycling Fund Institute, Apr, 2024 - Mar, 2026
   Hidenori Komatsu, Nobuyuki Tanaka, Ryoko Takikawa, Maryanne L. Fisher, Leif Edward, Ottesen Kennair, Elisabeth Oberzaucher, Ben Dickins, Tom Dickins

3. The effect of telomeres on relationship between testosterone and mating behavior of men
   Grant-in-Aid for Research Activity Start-up, Japan Society for the Promotion of Science, Apr, 2023 - Mar, 2025
   Ryoko Takikawa

4. The effect of telomeres on relationship between testosterone and mating behavior of men
   Waseda University Grants for Special Research Projects, Apr, 2023 - Mar, 2024
   Ryoko Takikawa

5. Birth weight and age at menarche: Influence of the prenatal environment and biological stress sensitivity on the timing of puberty
   Japan Foundation for Pediatric Research, Mar, 2022 - Apr, 2023
   Ryoko Takikawa

6. Maternal and child health from an evolutionary perspective: The relationship among maternal age, birth weight, and age at menarche
   Waseda University Grant for Psychological Research, Waseda University, Apr, 2021 - Mar, 2022
   Ryoko Takikawa

7. Basic and applied research on the pain-relieving effect of motion sensation
   Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Grant-in-Aid for JSPS Fellows, Japan Society for the Promotion of Science, Apr, 2017 - Mar, 2020
   Ryoko Takikawa

1. Social Sciences and Humanities Open
   Peer review
   Elsevier, Inc., Sep, 2025 - Present

2. Evolutionary Psychology
   Peer review
   SAGE Publications Ltd., Aug, 2025 - Present

3. Social Behavior and Personality: an international journal
   Peer review
   Scientific Journal Publishers Ltd., 2023 - Present

4. Career counseling session for Early Career Researcher, The Annual Conference of the Japanese Psychological Association Symposium
   Panel moderator, session chair, etc.
   The Japanese Psychological Association Early Career Psychologists Network, Sep, 2022 - Present

5. One-shot presentation for early career psychologists, The Annual Conference of the Japanese Psychological Association Symposium
   Review, evaluation
   The Japanese Psychological Association Early Career Psychologists Network, Sep, 2022 - Present

6. Participation fee support system for presenters, The Annual Conference of the Japanese Psychological Association
   Review, evaluation
   Japanese Psychological Association Early Career Psychologists Network, Jun, 2022 - Present

7. The development and evaluation of continuous fall prevention programs and monitoring fall-prevent methods to detect falls and support for elderly people at home
   Planning/Implementing academic research
   The Jikei University School of Medicine, Apr, 2018

1. Oriental medical approach to chronic musculoskeletal pain
   Lecturer, Planner, Investigator
   Hashimoto Clinic, Apr, 2017 - Mar, 2018

2. Clinical application of nonlinearity in biological signals (electroencephalogram, center of gravity sway, pulse wave)
   Planner, Investigator
   TAOS Co., Ltd., Apr, 2016 - Mar, 2018

1. Japan Student Services Organization. Exemption from repayment due to particularly outstanding performance
   Mar, 2023

2. 早稲田大学大学院博士後期課程若手研究者養成奨学金 採用
   Apr, 2018

3. Certified Psychologist 

2015