Salivary Testosterone Levels Research Articles

Menstrual Dysfunction, Hypoestrogenism, And Cardiac Parameters In Young Endurance Runners

PURPOSE: Menstrual dysfunction is common among endurance runners and may impact cardiovascular responses to exercise. The objective of this study was to examine the relationships among menstrual status, circulating levels of steroid hormones, cardiovascular function, and endurance performance in a group of female endurance athletes. METHODS: College-aged (18-22 yrs) female endurance distance runners reporting a history of eumenorrhea (EAs, n=11) or menstrual dysfunction (MDAs, n=9) performed a modified Bruce Protocol Treadmill Test. Salivary estradiol, testosterone, and cortisol levels, circulating lactic acid levels, and ECG data were collected pre- and post-run. Heart rate, VO2max, time to exhaustion, and rate of perceived exhaustion were measured pre-, during, and post-run. RESULTS: Athletes reporting menstrual dysfunction had significantly lower resting estradiol levels and higher testosterone levels than EAs, although these groups did not differ in training regimen, BMI, or body fat %. MDAs had significantly lower heart rates from prolonged ST intervals before, during and after the treadmill test. There were no differences in time to exhaustion, rate of perceived effort or VO2max between groups. CONCLUSION: Lower estradiol levels link neuroendocrine reproductive dysfunction with altered cardiovascular responses to training in female endurance athletes, though do not appear to influence submaximal performance. We propose that depressed heart rate and hypoestrogenism heart rates in young female athletes could aid in the early identification of the “athlete triad” and may indicated heightened risk for future cardiovascular disease.

Individual Differences in Women's Salivary Testosterone and Estradiol Following Sexual Activity in a Nonlaboratory Setting

ABSTRACTObjectives: The current study evaluated women's salivary testosterone and estradiol levels before and after exposure to sexual stimuli in a U.S. sex club. Methods: Behavioral data and salivary samples were collected from 19 women during semistructured interviews. Results: Findings demonstrate substantial individual differences in the magnitude and direction of women's hormonal changes following sexual activity. Conclusions: In an age of individualized medicine, these findings highlight the need to better understand factors shaping variation in physiological responses to sexual activity. Findings contribute to a relatively small and contradictory literature on women's hormonal responses to sexual stimuli.

Salivary Testosterone Is Consistently and Positively Associated with Extraversion: Results from The Netherlands Study of Depression and Anxiety

Background: Testosterone has been postulated as a ‘social' hormone, but the relationship between testosterone and personality traits linked with socially oriented behaviors such as extraversion remains unclear. The objective of our study was to investigate the association between baseline salivary testosterone levels and the Big Five personality traits. Methods: We studied the relationship between salivary testosterone (morning and evening) and NEO-FFI (Five-Factor Inventory) personality traits in 1,611 participants with lifetime or current depression and/or anxiety and 482 participants without depression/anxiety of the Netherlands Study of Depression and Anxiety (NESDA). Results: The personality domain of extraversion was independently associated with higher salivary testosterone, both in healthy subjects (β = 0.094; p = 0.04) and in subjects with lifetime or current depression and/or anxiety (β = 0.092; p < 0.001). In multivariable adjusted analyses, extraversion remained the only personality trait that was positively associated with salivary testosterone (β = 0.079; p = 0.006). Conclusion: We conclude that salivary testosterone is consistently and positively related to extraversion, supporting the notion of a hormonal basis of this personality trait, which may be linked to the tendency to strive for and maintain social status.

First pregnancy characteristics, postmenopausal breast density, and salivary sex hormone levels in a population at high risk for breast cancer

BackgroundIt remains unknown if later life breast cancer risk as determined by reproductive history is mediated by postmenopausal breast density and/or sex steroid levels. MethodsIncreased breast density is a strong surrogate for future breast cancer risk. A cross-sectional study with a longitudinal follow-up for breast health outcomes evaluated women without breast cancer (n=1023; 682=parous), drawn from a high risk postmenopausal population, with questionnaire- reported reproductive histories. The questionnaire was linked to prospective screening mammogram breast density measurements, and saliva biospecimens that were used to assess sex steroid hormone levels. ResultsExpected age- and postmenopause- related declines in salivary estradiol (E), progesterone (P), dehydroepiandrosterone (DHEA) and testosterone (T) levels were observed. This was most pronounced for DHEA and T, which were also the only postmenopausal hormone levels significantly associated with any reproductive characteristics: parity and breast feeding for DHEA, and age-at-first birth for T. Postmenopausal breast density was borderline significantly lower with parity and higher body mass index (BMI). After multivariate analysis, T was the only hormone level to retain any association (negative, p<0.05) with breast density. Conclusions and general significanceWhile reproductive characteristics, in particular parity, generally demonstrated independent associations with postmenopausal breast density and E, P and DHEA levels, T levels showed concordant inverse associations with age-at-first birth and breast density. These findings suggest that reproductive effects and later life salivary sex steroid hormone levels may have independent effects on later life breast density and cancer risk.

Relationship between salivary and serum testosterone levels in response to different exercise intensities.

The anabolic hormone testosterone (T) continues to be researched extensively in exercise studies, with blood serum or plasma samples collected routinely. This method is considered both valid and reliable; however, the collection process can be invasive and difficult during exercise. For this reason, non-invasive sampling, such as saliva collections, is increasing in popularity. To investigate the association between salivary and serum T before and after various intensities of exercise to assess the validity of saliva collection for T measurement. 12 endurance-trained males (Mean ± SD; VOVO2max 58.2 ± 6.4 ml/kg/min, 22 ± 4.6 years, BMI 21.6 ± 1.9) completed three 30-minute exercise (cycling) sessions at 40% (Low), 60% (Moderate), and 80% (High) of VO2max as well as a 30-minute resting Control session on four separate days. Salivary (s) and serum (S) samples were assessed for T prior to (Pre), immediately post (Post), and 30 minutes post (30 Min Post) each session. Low exercise caused a significant (p<0.05) increase in ST, but not sT, while Moderate and High exercise caused an increase (p<0.01) in both ST and sT. A strong positive correlation (Spearman [rs]) existed between sT and ST in the Moderate (rs = 0.912 [p<0.001; n=36; 12 subjects x 3 measurement times-samples]), and High (rs = 0.898 [p<0.001]) sessions, but not as strong for the Low (rs = 0.517 [p=0.001]) session. These results suggest that sT and ST levels are strongly associated to exercise. However, the exercise-related sT and ST responses-changes were more closely aligned at Moderate and High intensities, suggesting a greater validity between the saliva and serum responses to higher intensity exercise.

The reward value of infant facial cuteness tracks within-subject changes in women's salivary testosterone

“Baby schema” refers to infant characteristics, such as facial cues, that positively influence cuteness perceptions and trigger caregiving and protective behaviors in adults. Current models of hormonal regulation of parenting behaviors address how hormones may modulate protective behaviors and nurturance, but not how hormones may modulate responses to infant cuteness. To explore this issue, we investigated possible relationships between the reward value of infant facial cuteness and within-woman changes in testosterone, estradiol, and progesterone levels. Multilevel modeling of these data showed that infant cuteness was more rewarding when women's salivary testosterone levels were high. Moreover, this within-woman effect of testosterone was independent of the possible effects of estradiol and progesterone and was not simply a consequence of changes in women's cuteness perceptions. These results suggest that testosterone may modulate differential responses to infant facial cuteness, potentially revealing a new route through which testosterone shapes selective allocation of parental resources.

Differences in salivary testosterone, digit ratio and empathy between intellectually gifted and control boys

Testosterone was shown to organize brain structure and modulate cognitive functions. Higher prenatal testosterone exposure has been proposed to increase systemizing and to decrease empathizing. Whether intellectually gifted (IQ>130) individuals differ in these aspects is largely unexplored. The aim of this paper is to compare the prenatal testosterone exposure (reflected by 2D:4D), the actual testosterone levels, and the ability of empathizing and systemizing in gifted boys (N=66) and control boys of same age (N=80). The comparison revealed significantly lower salivary testosterone levels (d=−3.35, t=2.46, p=0.02) in gifted group compared to controls. Although the effect size was quite robust, this result did not remain significant after the correcting for multiple testing (new p value calculated after Bonferroni correction was 0.006). Lower left 2D:4D (standing for higher prenatal testosterone level; d=−1.33, t=4.96, p<0.0001) was observed in intellectually gifted boys compared to control boys surviving the correction for multiple testing. No significant difference between groups was found in the number of CAG repeats in gene encoding the androgen receptor (d=−0.06, t=0.38, p=ns). Intellectually gifted boys achieved significantly lower score in reading mind in the eye test (d=−0.75, t=3.38, p=0.003) that remained significant after correcting for multiple comparisons. It can be speculated that higher prenatal testosterone reflected by lower 2D:4D organizes the brain of gifted boys in a different way in comparison with controls. Consequences include differences in cognitive functions such as lower ability to mentalize—to understand the mental state of others. The physiological mechanisms of testosterone in intellectually gifted boys, especially at the molecular level remain to be elucidated.

Environmental and genetic contributors to salivary testosterone levels in infants.

Transient activation of the hypothalamic–pituitary–gonadal axis in early infancy plays an important role in male genital development and sexual differentiation of the brain, but factors contributing to individual variation in testosterone levels during this period are poorly understood. We measured salivary testosterone levels in 222 infants (119 males, 103 females, 108 singletons, 114 twins) between 2.70 and 4.80 months of age. We tested 16 major demographic and medical history variables for effects on inter-individual variation in salivary testosterone. Using the subset of twins, we estimated genetic and environmental contributions to salivary testosterone levels. Finally, we tested single nucleotide polymorphisms (SNPs) within ±5 kb of genes involved in testosterone synthesis, transport, signaling, and metabolism for associations with salivary testosterone using univariate tests and random forest (RF) analysis. We report an association between 5 min APGAR scores and salivary testosterone levels in males. Twin modeling indicated that individual variability in testosterone levels was primarily explained by environmental factors. Regarding genetic variation, univariate tests did not reveal any variants significantly associated with salivary testosterone after adjusting for false discovery rate. The top hit in males was rs10923844, an SNP of unknown function located downstream of HSD3B1 and HSD3B2. The top hits in females were two SNPs located upstream of ESR1 (rs3407085 and rs2295190). RF analysis, which reflects joint and conditional effects of multiple variants, indicated that genes involved in regulation of reproductive function, particularly LHCGR, are related to salivary testosterone levels in male infants, as are genes involved in cholesterol production, transport, and removal, while genes involved in estrogen signaling are related to salivary testosterone levels in female infants.

What makes a voice masculine: Physiological and acoustical correlates of women's ratings of men's vocal masculinity

Men's voices contain acoustic cues to body size and hormonal status, which have been found to affect women's ratings of speaker size, masculinity and attractiveness. However, the extent to which these voice parameters mediate the relationship between speakers' fitness-related features and listener's judgments of their masculinity has not yet been investigated.We audio-recorded 37 adult heterosexual males performing a range of speech tasks and asked 20 adult heterosexual female listeners to rate speakers' masculinity on the basis of their voices only. We then used a two-level (speaker within listener) path analysis to examine the relationships between the physiological (testosterone, height), acoustic (fundamental frequency or F0, and resonances or ΔF) and perceptual dimensions (listeners' ratings) of speakers' masculinity. Overall, results revealed that male speakers who were taller and had higher salivary testosterone levels also had lower F0 and ΔF, and were in turn rated as more masculine. The relationship between testosterone and perceived masculinity was essentially mediated by F0, while that of height and perceived masculinity was partially mediated by both F0 and ΔF.These observations confirm that women listeners attend to sexually dimorphic voice cues to assess the masculinity of unseen male speakers. In turn, variation in these voice features correlate with speakers' variation in stature and hormonal status, highlighting the interdependence of these physiological, acoustic and perceptual dimensions.

Associations between Salivary Testosterone Levels, Androgen-Related Genetic Polymorphisms, and Self-Estimated Ejaculation Latency Time.

IntroductionRecently, testosterone (T) has been shown to be associated with premature ejaculation (PE) symptoms in the literature. Furthermore, studies suggest that the etiology of PE is partly under genetic control.AimThe aim of this study was to reassess findings suggesting an association between testosterone (T) and a key symptom of PE, ejaculation latency time (ELT), as well as exploratively investigating associations between six androgen-related genetic polymorphisms and ELT.Materials and MethodsStatistical analyses were performed on a population-based sample of 1,429 Finnish men aged 18–45 years (M = 26.9, SD = 4.7). Genotype information was available for 1,345–1,429 of these (depending on the polymorphism), and salivary T samples were available from 384 men. Two androgen receptor gene-linked, two 5-alpha-reductase type 2-gene-linked, and two sex hormone-binding globuline gene-linked polymorphisms were genotyped.Main Outcome MeasuresEjaculatory function was assessed using self-reported ELT.ResultsWe found no association between salivary T levels and ELT. We found a nominally significant association between a 5-alpha-reductase type 2-gene-linked polymorphism (rs2208532) and ELT, but this association did not remain significant after correction for multiple testing. One single nucleotide polymorphism in the sex hormone-binding globulin gene (rs1799941) moderated (significantly after correction for multiple testing) the association between salivary T and ELT, so that A:A genotype carriers had significantly lower salivary T levels as a function of increasing ELT compared with other genotype groups.ConclusionsWe were unable to find support for the hypothesis suggesting an association between T levels and ELT, possibly because of the low number of phenotypically extreme cases (the sample used in the present study was population based). Our results concerning genetic associations should be interpreted with caution until replication studies have been conducted. Jern P, Westberg L, Ankarberg-Lindgren C, Johansson A, Gunst A, Sandnabba NK, and Santtila P. Associations between salivary testosterone levels, androgen-related genetic polymorphisms, and self-estimated ejaculation latency time. Sex Med 2014;2:107–114.

Changes in salivary estradiol predict changes in women's preferences for vocal masculinity

Although many studies have reported that women's preferences for masculine physical characteristics in men change systematically during the menstrual cycle, the hormonal mechanisms underpinning these changes are currently poorly understood. Previous studies investigating the relationships between measured hormone levels and women's masculinity preferences tested only judgments of men's facial attractiveness. Results of these studies suggested that preferences for masculine characteristics in men's faces were related to either women's estradiol or testosterone levels. To investigate the hormonal correlates of within-woman variation in masculinity preferences further, here we measured 62 women's salivary estradiol, progesterone, and testosterone levels and their preferences for masculine characteristics in men's voices in five weekly test sessions. Multilevel modeling of these data showed that changes in salivary estradiol were the best predictor of changes in women's preferences for vocal masculinity. These results complement other recent research implicating estradiol in women's mate preferences, attention to courtship signals, sexual motivation, and sexual strategies, and are the first to link women's voice preferences directly to measured hormone levels.

Effects of Estradiol, Progesterone and Testosterone on Oral Health Status and Gender Identification of Fetus in Women During Pregnancy

Background: The metabolism and immunology of the body are modified by hormones like progesterone, estrogen and testosterone as well as other local factors as dental plaque and calculus. The hormonal changes occurring during pregnancy may be associated with pregnancy gingivitis, gingival bleeding, and pregnancy tumor in the presence of local factors that may accentuate the gingival response. Aims of the study: 1.Find out the association between the oral health status and endogenous sex steroid salivary hormones level. 2.The assessment of fetus gender and compare the clinical and biochemical variables of pregnant with gingivitis who are carrying male fetuses and with those who are carrying female fetuses. Patients and methods: This study was done in Obstetrics and Gynecology Department at Al-Yarmouk Teaching Hospital, from February 2013 to July 2013. Clinical examination had been done for (53) study pregnant women with gingivitis and/or pregnancy tumor at the gestational age range (20-33) and (25) pregnant women with healthy gingiva at gestational age range (22-31), age matched control subjects for check number of gestational age and fetus gender with the consultation of specialist by sonography and confirm the gender in postpartum follow up visits. Oral clinical examination including an assessment of gingival inflammation (GI), plaque amount (PLI), gingival bleeding by (GBI), presence of pregnancy tumor, dental status (DMFT), and salivary flow rate (SFR) had also been done. Samples of whole unstimulated (resting) saliva were collected from all participants then investigated for sex steroids salivary hormonal levels of Estradiol, Progesterone and Testosterone. Results: Gingivitis pregnant and pregnant controls were matched in age. Oral health measurements including: GI, PI and GBI were significantly higher in study compared to controls, while SFR were less in study compared to controls and DMFT showed no significant difference between study and controls. Sex steroids salivary hormonal levels of Estradiol, Progesterone and Testosterone in study pregnant women were higher than that of controls. Prevalence of gingivitis among samples population of present study is 67.9% and the percentage of the presence of pregnancy tumor is 3.8%. PLI significantly correlated with elevated salivary hormones level of Testosterone and Estradiol and non-significantly correlated with salivary hormone level of progesterone.GI significantly correlated with elevated salivary hormones level of Estradiol, Progesterone and Testosterone. GBI significantly correlated with elevated salivary Estradiol hormone level and non-significantly correlated with salivary hormones level of Testosterone and Progesterone. Pregnancy tumor significantly correlated with elevated salivary hormones level of Estradiol, Progesterone and Testosterone. Pregnant women with gingivitis who were carrying females’ fetuses showed significant elevated salivary hormone level of Estradiol and significant elevated GI, PLI and GBI than pregnant women with gingivitis who are carrying males’ fetuses and show non-significant differences in salivary hormones level of Progesterone and Testosterone and non-significant differences in SFR and DMFT.

The Impact of Salivary Testosterone Levels on the Quality of Life of a Community-Based Population in Japan

Background: The Japanese population is aging extremely rapidly. Healthy longevity and quality of life (QOL) for the elderly depend on physical and mental well-being, which stem from physical activity of moderate frequency and intensity, and a balanced diet. A biological marker that is associated with healthy longevity and QOL is needed for the organization of a regional health policy. This study examined the relationships between salivary testosterone and QOL of the elderly inhabitants of Miyakojima, an island in Okinawa Prefecture. Methods: This community-based study included 193 elderly people (96 men and 97 women), aged 50 years or older, living in Miyakojima. The participants were randomly assigned from the database of Miyakojima inhabitants. QOL of the subjects was evaluated by questionnaires. Salivary testosterone was measured by enzyme immunoassay. We constructed a structural equation model (SEM) to analyze the relationships between saliva testosterone levels and lifestyle and the index of quality of life. Results: Salivary testosterone was available in 50 of 96 males and 29 of 97 females. The mean age of participants was 65.4±11.1 years (64.2±10.4 in males, 66.6±11.7 in females). The mean testosterone level was 53.8±51.5 pg/mL in males and 23.5±28.6 pg/mL in females. In SEM, the influence indices from the constructive concepts to observe variables showed relatively high path coefficients. Testosterone levels have positive effects on functional capacity, vitality, and QOL in men over 65. Conclusions: Salivary testosterone levels correlated with functional capacity, vitality, and QOL in men over 65. Salivary testosterone also correlated with women's QOL. For the assessment of functional capacity, vitality, and QOL in the local elderly population, salivary testosterone can be a good surrogate biological marker.

Digit ratio (2D:4D) as an indicator of body size, testosterone concentration and number of children in human males

Objectives: The 2nd to 4th digit ratio (2D:4D) is thought to reflect exposure to androgens during foetal development. This study examined the relationship between low (more masculine) and high (more feminine) 2D:4D and body size at different stages of the life course, adult testosterone levels and number of children among males.Methods: Five hundred and fifty-eight men from rural Poland at the Mogielica Human Ecology Study Site participated in this study. Life history data and anthropometric measurements were collected. Salivary morning and evening testosterone levels among 110 men from the same population were measured.Results: Low 2D:4D was related to higher birth weight (p = 0.04), higher birth length (p = 0.01), higher body mass during childhood and adolescence (p = 0.01), higher BMI (borderline significance, p = 0.06), higher number of children among fathers (p = 0.04) and higher testosterone levels during adulthood (p = 0.04).Conclusions: This study shows, for the first time in a single population, that digit ratio is related to sub-adult body size at different stages of the life course, adult testosterone levels and number of children. The observed results suggest that digit ratio might be a valuable predictor of male body size and reproductive characteristics.

Salivary testosterone measurements in growing pigs: validation of an automated chemiluminescent immunoassay and its possible use as an acute stress marker

This study aimed to validate the use of an automated chemiluminescent immunoassay analyser for salivary testosterone measurements in growing pigs and study how circadian pattern during daytime and stress can influence its values. The test method had intra- and inter-assay coefficient of variation lower than 10%. The method showed good linearity and recovery, and detection limits were low enough to detect salivary testosterone levels. No significant differences were observed in testosterone concentrations at different sampling time, and age and gender did not influence circadian pattern. In addition, this assay was used to quantify testosterone in two models of acute stress and, in both cases, significant increases (P < 0.01) in salivary testosterone were detected. Therefore, the automated assay system tested for porcine testosterone determinations would be suitable for its use in saliva samples and, furthermore, salivary testosterone levels could be used as a possible marker of acute stress in pigs.

Salivary testosterone and immunoglobulin A were increased by resistance training in adults with Down syndrome

This study was designed to assess the influence of resistance training on salivary immunoglobulin A (IgA) levels and hormone profile in sedentary adults with Down syndrome (DS). A total of 40 male adults with DS were recruited for the trial through different community support groups for people with intellectual disabilities. All participants had medical approval for participation in physical activity. Twenty-four adults were randomly assigned to perform resistance training in a circuit with six stations, 3 days per week for 12 weeks. Training intensity was based on functioning in the eight-repetition maximum (8RM) test for each exercise. The control group included 16 age-, gender-, and BMI-matched adults with DS. Salivary IgA, testosterone, and cortisol levels were measured by ELISA. Work task performance was assessed using the repetitive weighted-box-stacking test. Resistance training significantly increased salivary IgA concentration (P=0.0120; d=0.94) and testosterone levels (P=0.0088; d=1.57) in the exercising group. Furthermore, it also improved work task performance. No changes were seen in the controls who had not exercised. In conclusion, a short-term resistance training protocol improved mucosal immunity response as well as salivary testosterone levels in sedentary adults with DS.

Strength-training and biological rhythm of male sex hormone among judoists

Testosterone is a steroid hormone that is secreted by the testes with a diurnal rhythm and has a strong anti-catabolic (anabolic) effect on muscles. There is a strong relationship (r > 0.9) between concentrations of testosterone in the saliva and blood. The main purpose of the current study is to investigate the effect of strength-training on levels of salivary testosterone in male judoists. In a cross-sectional investigation, a population of 18 fit young male judoists (aged 17.0 ± 1.2 year, body mass 72 ± 3 kg, height 175 ± 3 cm, means ± SD), with at least 1.5 years of experience in judo classes was examined in Isfahan, Iran, in December, 2012. The period of testing consisted of two days of “rest” and two days of “exercise”. Subjects were randomly divided into two conditions that performed either the “rest” or “exercise” days during the first week, with the opposite type of day in the second week. The training regimen consisted of three repetitions of nine tasks, with 1 min of rest between each of the three sets, performed on alternate days for 8 weeks. Unstimulated saliva was collected (1–2 ml) every 2 h from 06:00 till 22:00 h. ANOVA with repeated measures was used to assess differences between the rest and exercise days. Strength-training sessions caused a significant decrease in testosterone levels immediately after exercise (p < 0.001), but there was no significant difference between the daily profiles of testosterone during the rest or exercise days (p > 0.05). It is concluded that strength-training does not significantly affect the normal biological rhythm of salivary testosterone during the waking period in male judoists.

Association between Digital Finger Ratio (2D:4D) and Salivary Testosterone level in Combative Sports and Non-Sportsmen

The second to fourth-digit-ratio (2D:4D), a putative marker of prenatal androgen action and a sexually dimorphic trait, has been suggested to be related with fitness and sports performance. But there very few studies which has evaluated the association between 2D:4D and the circulating levels of testosterone hormone. The objectives of the study were to examine the difference between 2d:4d and salivary testosterone hormone in 107 male combative sportsmen (42 = boxers, 37 = wrestlers & 28 = judokas) and 150 non-sportsmen (NSM) Length of index finger and ring finger of both left and right hand was measured with the help of digital vernier caliper. We found a significant difference in the digital finger ratio 2d:4d between the combative sportsmen and non sportsmen (Boxers v/s NSM t value -7.73, P < 0.01, Wrestlers v/s NSM t value – 5.60, P < 0.01 & Judokas t value – 4.75, P < 0.01). Further significant difference (Boxers v/s NSM t value -17.59, P < 0.01, Wrestlers v/s NSM t value – 18.03, P < 0.01 & Judokas t value – 13.75, P < 0.01) in the level of salivary testosterone hormone (pg/ml) between the combative sportsmen and non sportsmen was found. We suggest that low right-left 2D:4D is a predictive marker of testosterone receptiveness in men trained for the combative sports and this association is programmed by the action of prenatal testosterone.

Spatial abilities are not related to testosterone levels and variation in the androgen receptor in healthy young men

Androgens modulate brain functions such as cognition, emotions and ability. Several studies have shown a correlation between testosterone levels and mental rotation. The aim of the present study was to confirm the influence of salivary testosterone levels, 2D/4D ratio (such as a putative marker of prenatal testosterone), and sensitivity of androgen receptor on the mental rotation in healthy young men. Seventy-five healthy young men (age, 21.86 year) volunteered in this study. Mental rotation scores of our subjects were assessed using the Vandenberg and Kuse Mental Rotation Test. The 2D/4D finger length ratio as an indicator of prenatal testosterone was used as an average measurement of both hands. Correlation analysis revealed no correlation between salivary testosterone levels and mental rotation. However, we have observed a trend towards a negative correlation. There were no statistically significant results between 2D/4D ratio and mental rotation or between polymorphic three-nucleotide (CAG) repeats and mental rotation tests. Future studies should focus on other genetic determinants of spatial abilities, potentially genes involved in testosterone metabolism.

Intercollegiate Cross Country Competition: Effects of Warm-up and Racing on Salivary Levels of Cortisol and Testosterone

Intercollegiate Cross Country Competition: Effects of Warm-up and Racing on Salivary Levels of Cortisol and Testosterone