Turning Bias in Humans Is Influenced by Phase of the Menstrual Cycle

• Published in: Hormones and behavior Vol. 31; no. 1; pp. 65 - 74
• Main Authors: Mead, Larissa A., Hampson, Elizabeth
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.02.1997; Elsevier
• Subjects: Adult; Behavior - physiology; Behavioral psychophysiology; Biological and medical sciences; Estradiol - metabolism; Female; Fundamental and applied biological sciences. Psychology; Hormones and behavior; Humans; Menstrual Cycle - physiology; Progesterone - metabolism; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rotation; Human; Menstrual cycle; Estrogen; Goal directed movement; Estradiol; Rotation; Ovarian hormone; Body movement; Female; Progesterone; Sex steroid hormone; Laterality; Motricity
• ISSN: 0018-506X; 1095-6867
• DOI: 10.1006/hbeh.1997.1363

Previous studies have provided evidence that humans demonstrate subtle, but measurable, turning biases when tested in the absence of environmental constraints. Preferences for leftward or rightward rotation have been repeatedly demonstrated in rodents and appear to be modulated to a significant degree by ovarian hormones, particularly estrogen. In the present study, we examined the turning biases of adult women at the midluteal and menstrual phases of the menstrual cycle, associated with high and low levels of estradiol and progesterone, respectively. Saliva samples were collected during each test session, and salivary concentrations of estradiol and progesterone were measured using radioimmunoassays. Overall, a rightward-turning bias was evident; however, a minority of the women displayed consistent leftward biases. Among right-turning subjects, turning biases were significantly weaker at the midluteal phase than at the menstrual phase. These results suggest that the mechanisms underlying human turning biases are subject to modulation by ovarian hormones.