Human (Homo sapiens) responses to the pig (Sus scrofa) sex pheromone 5 alpha-androst-16-en-3-one

Previous studies have suggested that the pig sex pheromone 5 alpha-androst-16-en-3-one may function as a human sex pheromone. Two hundred male and female college students were assigned to one of four odor conditions (androstenone, methyl anthranilate, skatole, and a no-odor control) and were asked to rate photographs of a male stimulus and to rate their own mood in the presence of each odorant. There was a significant overall sex by treatment condition interaction. Men in the androstenone condition rated the stimulus male as more passive, and women in the androstenone condition rated themselves as less sexy; these effects were specific to the androstenone condition.     

Scent marking by male dwarf hamsters (Phodopus sungorus campbelli) in response to conspecific odors

Male hamsters (Phodopus sungorus campbelli) scent marked at greater frequencies in the presence of conspecific odor, either male or female, than in clean areas. Marking rates were not different between male and female odor conditions. In contrast, the pattern of investigation in response to conspecific odor did differ between the male and the female odor conditions. When male odors were used as stimuli, investigative sniffing increased at the scent marking sites but when female odors were used as stimuli investigative sniffing increased throughout the arena. Thus, male dwarf hamsters direct their scent marks at both male and female conspecifics, discriminate between male and female odor, and investigate in a different manner areas scent marked by males and females.     

Odor cue determinants of urine marking in male rats (Rattus norvegicus)

This study examined the spatial distribution of urine marking by sexually inexperienced male rats under six odor conditions: minimum odor (baseline), conspecific male urine, conspecific female urine, an animal's own urine, male gerbil urine, and amyl acetate. The gerbil urine and amyl acetate conditions were included to test the theory that marking, rather than being elicited by and directed as a display to appropriate conspecifics, occurred to the introduction of any novel or disruptive odor. The subject's own urine was used to test the theory that the animal marked to maintain an optimum level of its own odor in the environment. The results showed that marking was directed predominantly at objects in the environment over which the animal could readily pass. All odor conditions except "own odor" sharply increased marking over baseline levels. Marking decreased with repeated exposure to particular stimuli. The results strongly supported the theory that urine marking, at least in sexually inexperienced male rats, is produced by novel odor stimuli introduced into a familiar environment.     

Sex Differences on the Revised Beck Depression Inventory for Outpatients With Affective Disorders

The revised Beck Depression Inventory (BDI) was administered to 174 male and 276 female psychiatric outpatients diagnosed with affective disorders. The mean BDI scores, mean number of symptoms claimed, and corrected item-total correlations were comparable for both sexes, and the coefficients alpha for each sex was .88. Principal components analyses found four dimensions of depression underlying both sexes' BDI item-intercorrelation matrices. Although men and women had comparable dimensions with respect to weight loss, self-blame, and somatic-performance symptoms, men had affective and performance symptoms loading on the same factor, whereas women had affective and cognitive symptoms loading on the same dimension.     

Sex differences on the revised Beck Depression Inventory for outpatients with affective disorders

The revised Beck Depression Inventory (BDI) was administered to 174 male and 276 female psychiatric outpatients diagnosed with affective disorders. The mean BDI scores, mean number of symptoms claimed, and corrected item-total correlations were comparable for both sexes, and the coefficient alpha for each sex was .88. Principal components analyses found four dimensions of depression underlying both sexes' BDI item-intercorrelation matrices. Although men and women had comparable dimensions with respect to weight loss, self-blame, and somatic-performance symptoms, men had affective and performance symptoms loading on the same factor, whereas women had affective and cognitive symptoms loading on the same dimension.     

Odor recognition and identification: effect of labels over time

The effect of labels on recognition and identification of odors over time was assessed. 30 men and 30 women were presented 20 odors; half of the participants were also told a name for the odor as a label. Five min. and 60 min. later, all participants were given 20 odors (10 from the original set, 10 new) and asked whether each odor was new or old (odor recognition). The group given labels was also asked to recall the label provided (odor identification). Analysis indicated a significant effect of time on recognition. Significantly more odors were recognized at 5 min. than 60 min. The effect of label was also significant, with recognition being better for the Label condition than the No-Label condition. As for odor identification, women identified more labels than did men. Overall, odor recognition was better with labels soon after exposure, and the women were better at remembering the labels than the men.     

Noradrenergic control of odor recognition in a nonassociative olfactory learning task in the mouse

The present study examined the influence of pharmacological modulations of the locus coeruleus noradrenergic system on odor recognition in the mouse. Mice exposed to a nonrewarded olfactory stimulation (training) were able to memorize this odor and to discriminate it from a new odor in a recall test performed 15 min later. At longer delays (30 or 60 min), the familiar odor was no longer retained, and both stimuli were perceived as new ones. Following a post-training injection of the alpha(2)-adrenoceptor antagonist dexefaroxan, the familiar odor was still remembered 30 min after training. In contrast, both the alpha(2)-adrenoceptor agonist UK 14304 and the noradrenergic neurotoxin DSP-4 prevented the recognition of the familiar odor 15 min after the first exposure. Noradrenaline release in the olfactory bulb, assessed by measurement of the extracellular noradrenaline metabolite normetanephrine, was increased by 62% following dexefaroxan injection, and was decreased by 38%-44% after treatment with UK 14304 and DSP-4. Performance of mice in the recall test was reduced by a post-training injection of the beta-adrenoceptor antagonist propranolol or the alpha(1)-antagonist prazosin, thus implicating a role for beta- and alpha(1)-adrenoceptors in the facilitating effects of noradrenaline on short-term olfactory recognition in this model.     

Interspecies transmission of emotional information via chemosignals: from humans to dogs (<Emphasis Type="Italic">Canis lupus familiaris</Emphasis>)

We report a study examining interspecies emotion transfer via body odors (chemosignals). Do human body odors (chemosignals) produced under emotional conditions of happiness and fear provide information that is detectable by pet dogs (Labrador and Golden retrievers)? The odor samples were collected from the axilla of male donors not involved in the main experiment. The experimental setup involved the co-presence of the dog’s owner, a stranger and the odor dispenser in a space where the dogs could move freely. There were three odor conditions [fear, happiness, and control (no sweat)] to which the dogs were assigned randomly. The dependent variables were the relevant behaviors of the dogs (e.g., approaching, interacting and gazing) directed to the three targets (owner, stranger, sweat dispenser) aside from the dogs’ stress and heart rate indicators. The results indicated with high accuracy that the dogs manifested the predicted behaviors in the three conditions. There were fewer and shorter owner directed behaviors and more stranger directed behaviors when they were in the “happy odor condition” compared to the fear odor and control conditions. In the fear odor condition, they displayed more stressful behaviors. The heart rate data in the control and happy conditions were significantly lower than in the fear condition. Our findings suggest that interspecies emotional communication is facilitated by chemosignals.     

The Relationships between Ambivalent Sexism and Religiosity among Turkish University Students

This study explored the relationships among hostile sexism (HS), benevolent sexism (BS), and religiosity for men and women in Turkey, where Islam is the predominant religion. 73 male and 93 female university students completed measures of ambivalent sexism and religiosity. Replicating previous work with Christians, religiosity was a significant correlate of BS when HS was controlled, for both men and women. As predicted, and in contrast to previous research with Christians, partial correlations indicated that Muslim religiosity was a significant correlate of HS for men, when BS was controlled, but not for women. Women but not men showed a significant difference between religiosity’s partial correlations with HS and BS. The results were discussed in the light of relevant literature.     

Dimensions of the Male Gender Role: A Confirmatory Analysis in Men and Women

As researchers become more interested instudying the influences of the male gender role onpeople's physical and psychological well-being, measuresof several male role domains have been created,including psychological agency, traditional attitudestowards men, and masculine gender role stress (MGRS).These measures of the male gender role, however,typically have been constructed and validated using only samples of men. This restriction introducesquestions about the reliability and validity of theseinstruments in samples of women, leading to problemswhen generalizing findings to this group. The present study addressed these issues by examining thefactor structure, factor correlations, and latent meansof these three male role measures for a sample of mostlyCaucasian men and women, using multiple group confirmatory factor analytic techniques.Results showed only the dimensionality of the agenticpersonality traits differed significantly for men andwomen. The interrelationships among and latent means of agency, attitudes, and MGRS differed by sex.These findings demonstrate the utility of the currentconceptualization of sex and gender; in other words,that gender is not totally determined by sexand that men and women internalize many of the samegender cues, but differentially endorse them to varyingdegrees.     

Responsivity to two odorants, androstenone and amyl acetate, and the affective impact of odors on interpersonal relationships

Substantial variation exists in the importance of olfaction in influencing individuals' preferences, yet the sources of this variation remain elusive. The authors explored responsivity to 2 odorants as 1 potential source. Participants (N = 258) completed the Affective Impact of Odor Scale and were assessed for responsivity to the putative human pheromone androstenone and amyl acetate. Results showed a significant relationship between odorant responsivity and self-reports of the influence of odors. People able to smell androstenone more commonly reported odors as having a negative effect on interpersonal relationships than did people anosmic to androstenone, whereas responsivity to amyl acetate was associated with positive effects of odors on relationships. Responsivity to certain odorants may be an important factor affecting human social interactions.     

Intensity of odor and sensory irritation as a function of hexanal concentration and interpresentation intervals: an exploratory study

Hexanal is a suspected irritant in indoor air. Free-number magnitude estimation was used to measure intensity of odor and sensory irritation of two test concentrations (64 or 178 ppb) as a function of five concentrations and four interpresentation intervals. 9 of 12 participants (6 men, 6 women, ages 20-30 years) were able to detect the odor and report sensory irritation. The method of constant stimuli was applied to calculate the absolute thresholds of hexanal, which were 25 ppb for odor and 281 ppb for sensory irritation. Well-fitting power functions had a higher exponent for sensory-irritation intensity than for odor intensity (0.71 vs 0.66). A statistically significant effect on odor intensity was found for the concentration of presentations preceding the test stimuli and an interaction between concentrations and interpresentation intervals; however, sensory irritation was experienced to last longer than the odor of the same concentration.     

Similarity in the qualities of individual odors among kin and species in Turkish (Mesocricetus brandti) and golden (Mesocricetus auratus) hamsters.

In this investigation, the authors used habituation techniques to explore similarities and differences in the qualities of individual odors from hamsters. In Experiment 1, male Turkish hamsters (Mesocricetus brandti) treated flank-gland odors of 2 males from 1 litter as similar compared with the odor of a male from another litter, whether the odor donors were familiar or unfamiliar. At the same time, the Turkish hamsters discriminated between the subtle differences in the individual odors of their familiar brothers. In Experiment 2, male Turkish and golden hamsters (Mesocricetus auratus) treated the flank-gland odors of 2 unfamiliar, unrelated conspecifics as similar compared with the flank odor of a heterospecific individual. The results suggest that similarities in individual odors are related to genetic similarity of the odor donors. These similarities could provide a basis for different types of social recognition, including kin and species recognition.     

Olfactory self-recognition in a cichlid fish

Animal self-cognizance might be of importance in different contexts like territoriality, self-referent mate-choice or kin recognition. We investigated whether the cichlid fish Pelvicachromis taeniatus is able to recognize own olfactory cues. P. taeniatus is a cave breeding fish with pronounced brood care and social behavior. In the experiments we gave male cave owners the choice between two caves in which we introduced scented water. In a first experiment males preferred caves with their own odor over caves with the odor of an unfamiliar, unrelated male. To examine whether self-recognition is based rather on individual or on family cues we conducted two further experiments in which males could choose between their own odor and the odor of a familiar brother and between the odor of a familiar brother and an unfamiliar, unrelated male, respectively. Males preferred their own odor over that of a familiar brother suggesting individual self-referencing. Interestingly, males (at least outbred ones) preferred the odor of an unfamiliar, unrelated male over that of a familiar brother, maybe to avoid competition with kin. We discuss the results in the context of animal self-cognizance. All experiments were conducted with in- and outbred fish. Inbreeding did not negatively affect self-recognition.     

Imagery and olfactory stimulation

The purpose of the present study was to investigate a possible odor-emotion interaction by determining whether humans could differentially detect other humans' odor collected under varying emotional conditions. Odorants were collected from the axillary apocrine glands of four female donors, each of whom underwent different imagery induction procedures of anxiety, relaxation, and sexual arousal. The odorants were chemically preserved and later evaluated by 16 naive white male judges as to the presence of discriminatory odor cues. Judges' imagery was differentially related to the anxiety imagery-produced odorants but only for those produced by the most imaginative donors. The relaxation odorants of all donors were correlated. The judges were unable to detect the sexual imagery arousal odorants.     

The mind's nose: Effects of odor and visual imagery on odor detection

Abstract— We examined odor imagery by looking for its effects on detection of weak odors. Seventy-two healthy subjects performed a forced-choice odor detection task in one of three conditions: after being told to imagine an odor (odor imagery), after being told to imagine an object (visual imagery), or without having received imagery instructions (no-imagery control). For the two imagery conditions, the presented and imagined stimuli were either the same (matched) or different (mismatched). There was a significant difference between detection in the matched and mismatched conditions for odor imagery, but not for visual imagery. We conclude that our paradigm does measure odor imagery and that the effect of imagery on detection is both content- and modality-specific. Further, the difference between conditions was due to lower detection with mismatched odor imagery than without imagery, indicating that interference underlies the effect.     

Beta1-adrenoceptor or alpha1-adrenoceptor activation initiates early odor preference learning in rat pups: support for the mitral cell/cAMP model of odor preference learning

We proposed that mitral cell beta1-adrenoceptor activation mediates rat pup odor preference learning. Here we evaluate beta1-, beta2-, alpha1-, and alpha2-adrenoceptor agonists in such learning. The beta1-adrenoceptor agonist, dobutamine, and the alpha1-adrenoceptor agonist, phenylephrine, induced learning, and both exhibited an inverted U-curve dose-response relationship to odor preference learning. Phenylephrine-induced learning occurred in the presence of propranolol to prevent indirect activation of beta-adrenoceptors. Alpha1-adrenoceptor mediation may represent a novel mechanism inducing learning or may increase cAMP in mitral cells via indirect activation of GABA(B) receptors. Neither the beta2-adrenoceptor agonist, salbutamol, nor the alpha2-adrenoceptor agonist, clonidine, induced learning.     

An evaluation of the Italian version of the Fagerström Test for Nicotine Dependence

This study examined the psychometric properties of an Italian version of the Fagerstr?m Test for Nicotine Dependence in a sample of 593 smokers who were enrolled in a randomized Phase IV clinical trial to compare bupropion to placebo. This version was administered at baseline, and from each participant an expired air carbon monoxide (CO) measure was taken. Spearman correlations between the Total score and CO concentration were .27 in the combined sample and .27 and .25 among men and women. With respect to the internal consistency reliability, the coefficient alpha was low (alpha= .55) in the combined sample and among men (.59) and women (.50). While the Total score predicted abstinence at 7 wk., it was not significantly related to continuous abstinence at 12 mo. postrandomization. The properties of the Italian version of the Fagerstr?m Test for Nicotine Dependence appear to be consistent with other versions described in the literature.