Sex, menstrual cycle, and hormonal contraceptives influences on
global–local processing
In this research, the global-local paradigm was used to study the global advantage (GA) effect in men (with high testosterone levels), women in the mid-luteal phase (with high estradiol and progesterone levels), in the ovulatory phase (with high estradiol but low progesterone levels); and in the early follicular phase or hormonal contraceptive (HC) users (with low sex hormone levels). Processing level (global-local), congruency (congruent vs. incongruent), and attentional demand (divided vs. selective) were manipulated.
The divided-incongruent condition was sensitive to high estradiol and progesterone levels and, thus, women in the mid-luteal phase performed more locally while men performed more globally. The selective-incongruent condition was sensitive to high testosterone level and, thus, men were faster. Hormones also appeared to modulate congruency effects. Thus, low estradiol and progesterone levels in men promoted this congruency effect in the divided condition while low testosterone levels modulated the effect in the selective condition. Interestingly, HC users with reduced levels of all three hormones showed the congruency effect in both conditions. Finally, the GA reaction times of the ovulatory group differed from the early follicular and mid-luteal groups only in the congruent-selective condition, although performance did not correlate with sex hormone levels. This result is consistent with some brain effects of estradiol observed in the absence but not in the presence of progesterone.
Thus, sex, menstrual cycle and HC seem to modulate performance in the global-local task, possibly because of the influence of sex hormones on brain structures relevant to the task, such as the prefrontal cortex, anterior cingulate and basal ganglia. These factors represent an important source of variability in studies focused on the processing of hierarchical stimuli and allow apparently contradictory data to be explained.
Influence of estradiol and progesterone on spatial and verbal processing during three phases of the menstrual cycle: Modulating factors.
Several traditional studies have suggested that women's spatial ability improves during the early follicular phase of the menstrual cycle, characterized by the presence of reduced levels of estradiol and progesterone, and that verbal ability improves during the mid-luteal phase, with elevated levels of both hormones and/or the ovulatory phase, with high levels of estradiol alone. Recently, however, two reviews have questioned this possibility.
In the present work, we examined the differences between the studies that observed the expected effects and those that did not observe significant differences. This analysis has showed the existence of variables that seem to modulate the appearance or not of differences in spatial and verbal ability during the menstrual cycle. Thus, the use of more or less complex experimental tasks and the practice with them, genotype, age and sample size, constitute variables that modulate the neurocognitive effects of ovarian hormones and make their scientific study difficult. We stress the need to include not only the early follicular and mid-luteal phases of the menstrual cycle, as many studies do, but also the ovulatory phase, because sometimes, progesterone reverses the effects of estradiol, resulting in similar behavior during the early follicular and mid-luteal phases.
Taking these factors into account, we conclude that the most robust results are related to an improvement in mental rotation capacity during the early follicular phase when difficult tasks are used. There are also differences between the brain regions that are activated, in each phase, during performance of both spatial and verbal tasks, even though no behavioral differences are observed.
Contact:
- Antonio Bernal Benítez: antoniobernal@ugr.es
- María Alejandra Marful Quiroga: marful@ugr.es
- Daniela Paolieri: dpaolieri@ugr.es
Full References:
Marful, D. Paolieri, A. Bernal, Sex, menstrual cycle, and hormonal contraceptives influences on global–local processing, Psychoneuroendocrinology, Volume 134, 2021, 105430, ISSN 0306-4530, https://doi.org/10.1016/j.psyneuen.2021.105430.
Bernal, D. Paolieri, The influence of estradiol and progesterone on neurocognition during three phases of the menstrual cycle: modulating factors, Behavioural Brain Research, Volume 417, 2022, 113593, https://doi.org/10.1016/j.bbr.2021.113593.