The cerebello-hypothalamic tract: The relationship between estradiol, neuroticism, and cerebellar white matter

Abstract

Many reproductive aged women experience symptoms of Premenstrual Syndrome and Premenstrual Dysphoric Disorder. Nonetheless, research on the mechanisms behind these symptoms is limited. In the current paper, it is proposed that the steroid hormone estradiol is associated with these emotional symptoms, using neuroticism scores. In addition, it is expected that estradiol is related to cerebellar white matter volume, and the cerebello-hypothalamic tract (CHT). The CHT is a white matter projection, directly connecting the cerebellum with the hypothalamus. Data from a longitudinal cohort study at Leiden University Medical Centre, the “Braintime” project was used to examine the associations. MRI examinations were performed in twenty subjects, using a 3-tesla 3T unit, and the CHT was exposed using Diffusion Tensor Imaging. The CHT was found unilaterally in 11 cases (nleft = 9 and nright = 2), and bilaterally in 7 cases. However, no significant relations were found between estradiol and neuroticism, estradiol and cerebellar white matter volumes, and cerebellar white matter volumes and neuroticism. Nevertheless, a significant negative correlation was found between the CHT fiber count and white matter volume in cerebellar lobule IV. Furthermore, results showed that participants in which the CHT was found bilaterally scored significantly higher on the NEO-PI-R Depression scale. Hence, further research could examine whether there are significant associations between estradiol, white matter volume, and the CHT, taken age and individual ovulatory phases into account in data collection.