Functional Brain Asymmetry, Handedness and Age Characteristics of Climacterium In Women

Abstract

A total of 1985 women aged between 55 and 65 were distributed into two groups (145 left-handers and 1840 right-handers). They were asked to complete a questionnaire on the appearance of menopause, duration of menopausal transition and age of menopause. In left-handed women a significantly earlier appearance of premenopause was established together with a shorter menopause transition and an earlier occurrence of menopause. These results give grounds for a correlation between handedness, functional brain asymmetry, respectively and the genetically determined fading away of ovary steroidogenesis associated with the appearance and progression of the climacterium. In light of the available literature we assume that progressive reduction in ovarian function during climacterium is coupled with possible specific functioning of the hypothalamo-pituitary-gonadal axis, dependent on the type of hemispheric asymmetry.

Brain asymmetry, immunity, handedness

“…There are two supporting facts in this context: (a) it is known that interleukin-1β (IL-1β) can stimulate the HPA axis to increase the plasma levels of corticosterone, and (b) the cortical regulation of cortisol secretion is under the primary control of the right hemisphere [5,15]. Our previous investigations (although on different physiological functions) also provided evidence that hypothalamic-pituitary-glandular axes operate in a dependent relationship with individual differences in brain asymmetry [23,24]. Hori et al [25] focused their attention on the roles and mechanisms of neural communication between the brain and the immune system, and summarized: (a) primary and secondary lymphoid organs are sympathetically innervated; (b) different types of immunocompetent cells possess alpha-and beta-adrenergic receptors; (c) the exposure of lymphocytes and macrophages to adrenergic agonists in vitro modulates their functions; (d) a surgical or chemical sympathectomy alters the immune responses in rodents; (e) the altered activities of the splenic sympathetic nerves is causally related to the alteration in immunological responses (for instance NK cytotoxicity).…”

Asymmetry of the Neuroendocrine System

“…Furthermore, polycystic ovarian syndrome is predominantly associated with left-sided epileptiform discharges, whereas hypothalamic amenorrhea is related predominantly to right-sided discharges (8). A possible relationship between handedness and female reproductive functions is suggested by the earlier appearance of both menarche and menopause in left-handed women (12).…”

Lateralization of Squamous Cell Carcinomas in the Head-Neck Region

“…Sandson, Wen, and LeMay (1992) reported reversed cerebral asymmetry for both frontal and occipital widths in women with breast cancer. Left-handed women were reported to have an earlier age at menopause than right-handed women (Leidy, 1990;Nikolova, Negrev, & Stoyanov, 1996;Dane, Reis, & Pasinlioglu, 1999;Dane, Kumtepe, Pasinlioglu, & Aksoy, 2004).…”