Menstrual cycle phases and female receptivity to a courtship solicitation: an evaluation in a nightclub

Previous research has demonstrated that female behaviors toward men or sexual interest are different across the menstrual cycle. However, women's receptivity to an explicit courtship solicitation still remained in question. In a field experiment, 20-year-old women were approached by 20-year-old male confederates in nightclubs and solicited to dance during the period when slow songs were played. A survey was administered to the women in order to obtain information about the number of days since the onset of previous menses. It was found that women in their fertile phase agreed more favorably to the dance request than women in their luteal phase or in their menstrual phase.     

Hormones and social monitoring: Menstrual cycle shifts in progesterone underlie women's sensitivity to social information

During the luteal phase of the menstrual cycle, women's bodies prepare themselves for possible pregnancy and this preparation includes a dramatic increase in progesterone. This increase in progesterone may underlie a variety of functionally relevant psychological changes designed to help women overcome challenges historically encountered during pregnancy (e.g., warding off social threats and recruiting allies). This paper reports data supporting the hypothesis that increases in progesterone during the luteal phase underlie heightened levels of social monitoring—that is, heightened sensitivity to social cues indicating the presence of social opportunity or threat. Increases in progesterone during the luteal phase were associated with increased accuracy in decoding facial expressions (Study 1) and increased attention to social stimuli (Study 2). Findings suggest that increases in progesterone during the luteal phase may be linked functionally with low-level perceptual attunements that help women effectively navigate their social world.     

Adaptive attentional attunement: evidence for mating-related perceptual bias

Substantial evidence suggests that physical attractiveness plays an important role in shaping overt mating preferences, judgments, and choices. Relatively few studies, however, have investigated the hypothesis that perceivers are attuned to signs of attractiveness at early, lower-order stages of social perception. In the current research, a visual cueing task was used to assess biases in attentional disengagement—the extent to which people's attention becomes “stuck” on particular social stimuli. Findings indicate that, consistent with some evolutionary theories, perceivers of both sexes exhibited attentional attunement to attractive women, but not attractive men. Additional findings suggest that this bias was pronounced in sexually unrestricted men and in women who felt insecure about a current romantic relationship. This research provides novel evidence for adaptive, lower-order perceptual attunements in the domain of human mating.     

Menstrual cycle: Effect on sweetness preferences in women

Variations in how pleasant sugar solutions are, as rated by women, occur at different stages of the menstrual cycle. Following a glucose meal sweet solutions become less pleasant, but this shift is slower at the time of ovulation. The significance of these changes is discussed.     

Menstrual cycle characteristics of seasonally breeding rhesus monkeys

Rhesus monkeys in seminatural environments exhibit a distinct seasonal mating cycle with conceptions restricted to the fall and winter months. In the present study, the characteristics of menstrual cycles were examined during a 1-year period in twelve rhesus monkeys in whom pregnancy was prevented. Menses occurred throughout the year, but ovulations were observed only in the fall and winter months. Menses in the spring and summer months occurred irregularly and were associated exclusively with anovulatory cycles. The total number of ovulations exhibited by these females during the breeding season ranged from two to six and was positively related to body weight, mean luteal phase progesterone (P) levels of normal cycles and social dominance rank. Ovulations with a short luteal phase were exhibited by four females (seven cycles), with the likelihood of occurrence increasing as the breeding season progressed. The incidence of abnormal cycles was predicted from the linear combination of parity, body weight and luteal phase P of normal ovulatory cycles. These results suggest that during the seasonally delimited period of ovulation, females exhibit a range in the quality and quantity of ovulations which may be predicted by certain idiosyncratic physical and behavioral traits.     

Menstrual cycle phase affects discrimination of infant cuteness

Recent studies have shown that women are more sensitive than men to subtle cuteness differences in infant faces. It has been suggested that raised levels in estradiol and progesterone may be responsible for this advantage. We compared young women's sensitivity to computer-manipulated baby faces varying in cuteness. Thirty-six women were tested once during ovulation and once during the luteal phase of their menstrual cycle. In a two alternative forced-choice experiment, participants chose the baby which they thought was cuter (Task 1), younger (Task 2), or the baby that they would prefer to babysit (Task 3). Saliva samples to assess levels of estradiol, progesterone and testosterone were collected at each test session. During ovulation, women were more likely to choose the cuter baby than during the luteal phase, in all three tasks. These results suggest that cuteness discrimination may be driven by cyclic hormonal shifts. However none of the measured hormones were related to increased cuteness sensitivity. We speculate that other hormones than the ones measured here might be responsible for the increased sensitivity to subtle cuteness differences during ovulation.     

Gender difference of unconscious attentional bias in high trait anxiety individuals

By combining binocular suppression technique and a probe detection paradigm, we investigated attentional bias to invisible stimuli and its gender difference in both high trait anxiety (HTA) and low trait anxiety (LTA) individuals. As an attentional cue, happy or fearful face pictures were presented to HTAs and LTAs for 800 ms either consciously or unconsciously (through binocular suppression). Participants were asked to judge the orientation of a gabor patch following the face pictures. Their performance was used to measure attentional effect induced by the cue. We found gender differences of attentional effect only in the unconscious condition with HTAs. Female HTAs exhibited difficulty in disengaging attention from the location where fearful faces were presented, while male HTAs showed attentional avoidance of it. Our results suggested that the failure to find attentional avoidance of threatening stimuli in many previous studies might be attributed to consciously presented stimuli and data analysis regardless of participants' gender. These findings also contributed to our understanding of gender difference in anxiety disorder.     

Menstrual cycle variation in women's preferences for the scent of symmetrical men.

Evidence suggests that female sexual preferences change across the menstrual cycle. Women''s extra-pair copulations tend to occur in their most fertile period, whereas their intra-pair copulations tend to be more evenly spread out across the cycle. This pattern is consistent with women preferentially seeking men who evidence phenotypic markers of genetic benefits just before and during ovulation. This study examined whether women''s olfactory preferences for men''s scent would tend to favour the scent of more symmetrical men, most notably during the women''s fertile period. College women sniffed and rated the attractiveness of the scent of 41 T-shirts worn over a period of two nights by different men. Results indicated that normally cycling (non-pill using) women near the peak fertility of their cycle tended to prefer the scent of shirts worn by symmetrical men. Normally ovulating women at low fertility within their cycle, and women using a contraceptive pill, showed no significant preference for either symmetrical or asymmetrical men''s scent. A separate analysis revealed that, within the set of normally cycling women, individual women''s preference for symmetry correlated with their probability of conception, given the actuarial value associated with the day of the cycle they reported at the time they smelled the shirts. Potential sexual selection processes and proximate mechanisms accounting for these findings are discussed.     

Menstrual cycle patterns of hormones and sexual behavior in gorillas

Oppositely sexed pairs of gorillas were tested behaviorally during the menstrual cycle to determine the relationship between hormone concentrations of the female and the frequency of sexual activity by the pair. Five females were tested individually during two cycles with each of two males, but serum samples for hormone assay were obtained from each female only during the first cycle of testing. There was no clear relationship between hormones and behavior for the single cycle in which the serum samples were obtained, with the exception that no copulations occurred after the early luteal phase, when progesterone was greater than 5 ng/ml. Normalized behavioral data from all four test cycles for all pairs suggested that female-solicited copulations were restricted primarily to the periovulatory period. Male sexual initiative (by one of the males) accounted for most copulations temporally dissociated from the periovulatory period. Normalized hormone data for all of the females suggested that (1) attractivity was associated with estradiol concentrations during the follicular phase, (2) proceptivity with estradiol and testosterone at midcycle, whereas (3) receptivity was not associated with hormone patterns or cycle phase. The data suggest that hormones are one of several variables that contribute to the regulation of sexual behavior in gorillas.     

Menstrual cycle effects on performance of mental arithmetic task

The purpose of this research was to identify the relationship between task performance and menstrual cycle. The difference of performance on menstrual cycle phase was investigated. The task was the mental arithmetic task which involved the non-sequential and higher order cognitive processes. The duration of the experiment was twenty minutes. Two-way analysis of variance by repeated-measures design was used to examine the differences in task performance between phases and temporal variations. Results showed that there was a significant difference in correct input time during temporal variations though there was no significant difference between phases. Moreover, the relationships between phases and intra-individual variations in task performance were examined using coefficient of variance (CV). CVs were plotted in three dimensions to examine the relationships between intra-individual variations and phases. Based on CVs, the subjects who showed differences were classified into two groups: those with a small difference in three phases and those with a difference every phase. The phase which indicated large CV changed with individuals.     

Menstrual cycle exhibits no effect on postprandial lipemia.

Menstrual cycle effects on postprandial lipemia were investigated in 13 healthy women. They were monitored (dietary intake, basal body temperature) for a period of one cycle. Statistically significant follicular-luteal differences were neither observed between fasting triglyceride serum levels nor between areas under triglyceride response curves after a standardized oral fat load.     

Menstrual cycle phase alters women's sexual preferences for composers of more complex music

Over 140 years ago Charles Darwin first argued that birdsong and human music, having no clear survival benefit, were obvious candidates for sexual selection. Whereas the first contention is now universally accepted, his theory that music is a product of sexual selection through mate choice has largely been neglected. Here, I provide the first, to my knowledge, empirical support for the sexual selection hypothesis of music evolution by showing that women have sexual preferences during peak conception times for men that are able to create more complex music. Two-alternative forced-choice experiments revealed that woman only preferred composers of more complex music as short-term sexual partners when conception risk was highest. No preferences were displayed when women chose which composer they would prefer as a long-term partner in a committed relationship, and control experiments failed to reveal an effect of conception risk on women''s preferences for visual artists. These results suggest that women may acquire genetic benefits for offspring by selecting musicians able to create more complex music as sexual partners, and provide compelling support for Darwin''s assertion ‘that musical notes and rhythm were first acquired by the male or female progenitors of mankind for the sake of charming the opposite sex’.     

Menstrual cycle phase dissociation of blood glucose homeostasis during exercise

The purpose of this investigation was to evaluate the effects of 24-h carbohydrate-poor diet on metabolic and hormonal responses induced by prolonged exercise in both follicular (FP) and luteal (LP) phases of the menstrual cycle. At mid-FP and at mid-LP, seven eumenorrheic young women [means +/- SE; chronological age, 21.1 +/- 0.6 yr; O2 uptake (VO2) peak, 43.7 +/- 2.0 ml X kg-1 X min-1; body fat, 19.2 +/- 2.0%] were subjected to a 90-min bicycle exercise period at an intensity representing 63% of their measured VO2 peak. Venous blood samples obtained before and during exercise were analyzed for levels of substrates (glucose, lactate, free fatty acids, glycerol) and hormones (luteinizing hormone, progesterone, estradiol, insulin, glucagon, cortisol, catecholamines). Contrary to FP, a significant (P less than 0.01) decrease in blood glucose concentration was observed after 70 and 90 min of exercise during LP. Significant phase differences were also observed for blood lactate (highest in FP), cortisol (highest in LP), and progesterone (highest in LP). Although not significantly different, tendencies for menstrual phase dissociations were noticed for some of the other measured variables. Hence, a menstrual phase dissociation in circulating glucose level, unmasked by a prolonged exercise performed after a 24-h carbohydrate-poor diet, suggests to the authors a specific metabolic involvement for gonadotrophic and/or gonadal hormones.     

Menstrual cycle phase affects temperature regulation during endurance exercise.

We investigated whether menstrual cycle phase would affect temperature regulation during an endurance exercise bout performed at room temperature (Ta) of 22 degrees C and 60% relative humidity. Nine eumenorrheic women [age 27.2 +/- 3.7 yr, peak O2 uptake (VO2) 2.52 +/- 0.35 l/min] performed 60 min of cycle exercise at 65% of peak VO2. Subjects were tested in both midfollicular (F) and midluteal (L) phases, although one woman did not show a rise in serum progesterone (P4) that is typically evident 1 wk after ovulation. VO2, rectal (Tre) and skin (Tsk) temperatures, heart rates (HR), and ratings of perceived exertion (RPE) were measured throughout exercise. Sweat loss (SL) was estimated from pre- and postexercise body weight differences. VO2, SL, and Tsk were not affected by menstrual cycle phase. Preexercise Tre was 0.3 degrees C higher during L than during F conditions, and this difference increased to 0.6 degrees C by the end of exercise (P less than 0.01). Compared with F, HRs during L were approximately 10 beats/min greater (P less than 0.001) at all times, whereas RPE responses were significantly greater (P less than 0.01) by 50 min of cycling. No differences in any measured values were found in the subject whose P4 was low in both test conditions. Results indicate that thermoregulation (specifically, regulation of Tre), as well as cardiovascular strain and perception of exercise, was adversely affected during the L phase.     

Menstrual cycle variation in spatial ability: relation to salivary cortisol levels

This study examined whether menstrual cycle phase was associated with performance on the Primary Mental Abilities Test of Spatial Relations, a test of mental rotation, in undergraduate students (N = 82). As cortisol levels also vary across the menstrual cycle under conditions of stress and influence cognitive performance, saliva samples were obtained before and after the test session to examine whether cortisol levels were related to between- and within-group differences in spatial performance. Men scored higher on the spatial test than all the groups of women, although the difference between men and women in the menstrual phase was not significant. Women in the luteal phase scored lower than the menstrual, follicular, and oral contraceptive user groups of women. There were no sex or menstrual cycle differences in cortisol levels, and no association between cortisol levels and spatial performance. The poorer performance of women in the luteal phase was not related to differences in ratings of perceived stress, perceived success on the test, or mood. Although menstrual cycle phase accounted for a significant proportion of the variance (15%) in performance on the spatial test, this does not explain why men outperformed women regardless of the phase of the cycle. Thus, there are clearly several other variables, sociocultural and physiological, involved in mediating individual differences in spatial performance.     

Food catches the eye but not for everyone: a BMI-contingent attentional bias in rapid detection of nutriments

An organism's survival depends crucially on its ability to detect and acquire nutriment. Attention circuits interact with cognitive and motivational systems to facilitate detection of salient sensory events in the environment. Here we show that the human attentional system is tuned to detect food targets among nonfood items. In two visual search experiments participants searched for discrepant food targets embedded in an array of nonfood distracters or vice versa. Detection times were faster when targets were food rather than nonfood items, and the detection advantage for food items showed a significant negative correlation with Body Mass Index (BMI). Also, eye tracking during searching within arrays of visually homogenous food and nonfood targets demonstrated that the BMI-contingent attentional bias was due to rapid capturing of the eyes by food items in individuals with low BMI. However, BMI was not associated with decision times after the discrepant food item was fixated. The results suggest that visual attention is biased towards foods, and that individual differences in energy consumption--as indexed by BMI--are associated with differential attentional effects related to foods. We speculate that such differences may constitute an important risk factor for gaining weight.