and females have consistent active working memory networks composed of both middle frontal gyri, the left cingulate gyrus, the right precuneus, the left inferior and superior parietal lobes, the right claustrum, and the left middle temporal gyrus. although the same brain networks are used for working memory, specific regions are sex-specific. sex differences were evident in other networks, as women also tend to have higher activity in the prefrontal and limbic regions, such as the anterior cingulate, bilateral amygdala, and right hippocampus, while men tend to have a distributed network spread out among the cerebellum, portions of the superior parietal lobe, the left insula, and bilateral thalamus. a 2017 review from the perspective of large-scale brain networks hypothesized that women's higher susceptibility to stress-prone diseases such as posttraumatic stress disorder and major depressive disorder, in which the salience network is theorized to be overactive and to interfere with the executive control network, may be due in part, along with societal exposure to stressors and the coping strategies that are available to women, to underlying sex-based brain differences. neurochemical differences hormones gonadal hormones, or sex hormones, include androgens (such as testosterone) and estrogens (such as estradiol), which are steroid hormones synthesized primarily in the testes and ovaries, respectively. sex hormone production is regulated by the gonadotropic hormones luteinizing hormone (lh) and follicle-stimulating hormone (fsh), whose release from the anterior pituitary is stimulated by gonadotropin-releasing hormone (gnrh) from the hypothalamus. steroid hormones have several effects on brain development as well as maintenance of homeostasis throughout adulthood. estrogen receptors have been found in the hypothalamus, pituitary gland, hippocampus, and frontal cortex, indicating the estrogen plays a role in brain development. gonadal hormone receptors have also been found in the basal fore-brain nuclei. estrogen and the female brain estradiol influences cognitive function, specifically by enhancing learning and memory in a dose-sensitive manner. too much estrogen can have negative effects by weakening performance of learned tasks as well as hindering performance of memory tasks; this can result in females exhibiting poorer performance of such tasks when compared to males. ovariectomies, surgeries inducing menopause, or natural menopause cause fluctuating and decreased estrogen levels in women. this in turn can "attenuate the effects" of endogenous opioid peptides. opioid peptides are known to play a role in emotion and motivation. the content of β-endorphin (β-ep), an endogenous opioid peptide, has been found to decrease (in varying amounts/brain region) post ovariectomy in female rats within the hypothalamus, hippocampus, and pituitary gland. such a change in β-ep levels could be the cause of mood swings, behavioral disturbances, and hot flashes in post menopausal women. progesterone and the male and female brain progesterone is a steroid hormone synthesized in both male and female brains. it contains characteristics found in the chemical nucleus of both estrogen and androgen hormones. as a female sex hormone, progesterone is more significant in females than in males. during the menstrual cycle, progesterone increases just after the ovulatory phase to inhibit luteinizing hormones, such as oxytocin absorption. in men, increased progesterone has been linked to adolescents with suicidal ideation. testosterone and the male brain the gonadal hormone testosterone is an androgenic, or masculinizing, hormone that is synthesized in both the male testes and female ovaries, at a rate of about 14,000 μg/day and 600 μg/day, respectively. testosterone exerts organizational effects on the developing brain, many of which are mediated through estrogen receptors following its conversion to estrogen by the enzyme aromatase within the brain.