Laterality and imbalance of muscle stiffness relate to personality

Naoki Nakaya, Hiroaki Kumano, Keiji Minoda, Motoyori Kanazawa, Shin Fukudo

Research output: Contribution to journalArticle

3 Citations (Scopus)


The authors' purpose in this study was to test the hypothesis that laterality and imbalance of muscle stiffness relate to personality. The authors selected 23 healthy volunteers and divided them into two groups based on the predominance of muscle stiffness on the left or right side. Imbalance of muscle stiffness was calculated as the absolute value of the difference of muscle stiffness between the right and left sides. The authors evaluated personality with the Japanese version of the Eysenck Personality Questionnaire. Subjects with left predominant muscle stiffness of the rectal abdominis had significantly higher neuroticism score than those with right predominant muscle stiffness. Subjects with more imbalance of muscle stiffness in the latissimus dorsi and in the trapezius had significantly higher neuroticism and psychoticism scores than those with less imbalance. The findings suggest that laterality and imbalance of muscle stiffness relate to personality.

Original languageEnglish
Pages (from-to)5-9
Number of pages5
JournalBehavioral Medicine
Issue number1
Publication statusPublished - 2004 Mar
Externally publishedYes



  • Eysenck Personality Questionnaire
  • Imbalance
  • Laterality
  • Muscle stiffness
  • Neuroticsm
  • Psychoticism

ASJC Scopus subject areas

  • Psychiatry and Mental health

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