Resting States Are Resting Traits – An fMRI Study of Sex Differences and Menstrual Cycle Effects in Resting State Cognitive Control Networks

Abstract

To what degree resting state fMRI is stable or susceptible to internal mind states of the individual is currently an issue of debate. To address this issue, the present study focuses on sex differences and investigates whether resting state fMRI is stable in men and women or changes within relative short-term periods (i.e., across the menstrual cycle). Due to the fact that we recently reported menstrual cycle effects on cognitive control based on data collected during the same sessions, the current study is particularly interested in fronto-parietal resting state networks. Resting state fMRI was measured in sixteen women during three different cycle phases (menstrual, follicular, and luteal). Fifteen men underwent three sessions in corresponding time intervals. We used independent component analysis to identify four fronto-parietal networks. The results showed sex differences in two of these networks with women exhibiting higher functional connectivity in general, including the prefrontal cortex. Menstrual cycle effects on resting states were non-existent. It is concluded that sex differences in resting state fMRI might reflect sexual dimorphisms in the brain rather than transitory activating effects of sex hormones on the functional connectivity in the resting brain.

Sex differences in associations of arginine vasopressin and oxytocin with resting‐state functional brain connectivity

“…Fourth, while we did not control for parity, menopausal stage, endogenous hormone cycling (menstrual cycle) or exogenous hormone administration (e.g., oral contraceptive pills). Some (Petersen et al 2014), but not all studies (Hjelmervik et al 2014), demonstrate the effects of sex steroid hormones on brain connectivity. However, there was only a small proportion of women in the present study on oral contraceptives.…”

“…OT and AVP may have sex-dependent associations with cognitive and emotional brain networks, particularly in ones showing sex differences (Hjelmervik et al 2014; Sacher et al 2013). To our knowledge, no study has examined associations between these peripheral hormones and functional brain connectivity.…”

Predicting personality from network-based resting-state functional connectivity

“…We additionally used a network with whole-brain coverage consisting of 264 nodes (we here refer to it as Connectome ; Power et al 2011) to predict the five personality traits to test if personality can be better predicted by specific functional networks or a rather unspecific whole-brain network. In addition, in light of the previous findings of sexual dimorphism in the relationships between brain structure and personality traits (Nostro et al 2016) as well as gender differences in RSFC (Allen et al 2011; Filippi et al 2013; Hjelmervik et al 2014; Weis et al 2017) and personality (Yang et al 2015), these analyses were performed in a gender-mixed sample as well as separately in male and female subsamples.…”

Hippocampal fractional amplitude of low‐frequency fluctuation and functional connectivity changes in premenstrual syndrome

“…In addition, a functional connectivity (FC) method is used to describe the relationships between the neuronal activation patterns of anatomically distinct brain regions, revealing the level of functional communication between them . Two recent studies of resting state connectivity in females have demonstrated that the FC method shows sensitivity to investigate resting state connectivity data across the menstrual cycle . Thus, combining fALFF and FC may provide new insight into the complex role of the HIPP in the neural mechanisms of PMS.…”