RESUMO
Human body odour is important in modulating self-perception and interactions between individuals. Artificial fragrances have been used for thousands of years to manipulate personal odour, but the nature and extent of influences on person perception are relatively unexplored. Here we test the effects of a double-blind manipulation of personal odour on self-confidence and behaviour. We gave to male participants either an aerosol spray containing a formulation of fragrance and antimicrobial agents or an otherwise identical spray that lacked these active ingredients. Over several days, we found effects between treatment groups on psychometric self-confidence and self-perceived attractiveness. Furthermore, although there was no difference between groups in mean attractiveness ratings of men's photographs by a female panel, the same women judged men using the active spray as more attractive in video-clips, suggesting a behavioural difference between the groups. Attractiveness of an individual male's non-verbal behaviour, independent of structural facial features, was predicted by the men's self-reported proclivity towards the provided deodorant. Our results demonstrate the pervasive influence of personal odour on self-perception, and how this can extend to impressions on others even when these impressions are formed in the absence of odour cues.
Assuntos
Comportamento , Odorantes , Autoimagem , Desejabilidade Social , Adulto , Método Duplo-Cego , Feminino , Humanos , Estudos Longitudinais , Masculino , Inquéritos e Questionários , Adulto JovemRESUMO
Many studies have investigated the physical cues that influence face preferences. By contrast, relatively few studies have investigated the effects of facial cues to the direction and valence of others' social interest (i.e. gaze direction and facial expressions) on face preferences. Here we found that participants demonstrated stronger preferences for direct gaze when judging the attractiveness of happy faces than that of disgusted faces, and that this effect of expression on the strength of attraction to direct gaze was particularly pronounced for judgements of opposite-sex faces (study 1). By contrast, no such opposite-sex bias in preferences for direct gaze was observed when participants judged the same faces for likeability (study 2). Collectively, these findings for a context-sensitive opposite-sex bias in preferences for perceiver-directed smiles, but not perceiver-directed disgust, suggest gaze preference functions, at least in part, to facilitate efficient allocation of mating effort, and evince adaptive design in the perceptual mechanisms that underpin face preferences.
Assuntos
Adaptação Biológica/fisiologia , Atenção/fisiologia , Comportamento de Escolha/fisiologia , Expressão Facial , Percepção Visual/fisiologia , Análise de Variância , Beleza , Feminino , Humanos , Masculino , Estimulação Luminosa , Fatores SexuaisRESUMO
Many studies have used visual adaptation to investigate how recent experience with faces influences perception. While faces similar to those seen during adaptation phases are typically perceived as more 'normal' after adaptation, it is possible to induce aftereffects in one direction for one category (e.g. female) and simultaneously induce aftereffects in the opposite direction for another category (e.g. male). Such aftereffects could reflect 'category-contingent' adaptation of neurons selective for perceptual category (e.g. male or female) or 'structure-contingent' adaptation of lower-level neurons coding the physical characteristics of different face patterns. We compared these explanations by testing for simultaneous opposite after effects following adaptation to (a) two groups of faces from distinct sex categories (male and female) or (b) two groups of faces from the same sex category (female and hyper-female) where the structural differences between the female and hyper-female groups were mathematically identical to those between male and female groups. We were able to induce opposite aftereffects following adaptation between sex categories but not after adaptation within a sex category. These findings indicate the involvement of neurons coding perceptual category in sex-contingent face aftereffects and cannot be explained by neurons coding only the physical aspects of face patterns.
Assuntos
Cognição , Face , Percepção Visual , Feminino , Humanos , Masculino , Fatores SexuaisRESUMO
Previous studies have reported transient pupil constrictions to basic visual attributes (e.g., color and movement) that are processed along the ventral and the dorsal pathways. Specific cortical areas are activated more for faces than most other types of stimuli, raising the possibility that stimulus-specific transient pupil constrictions might also occur for faces. Such pupil responses may be sensitive to stimulus orientation and species since these parameters have been found to affect electrophysiological and behavioral responses to faces. Here we show transient pupil constrictions to upright human faces that are greater than those to scrambled versions, inverted versions, or macaque monkey faces. Similar to findings from electrophysiological studies, the inversion effect occurred for human faces but not macaque faces. Collectively, our findings show that transient pupil constrictions to faces are sensitive to the same parameters that have been found to influence electrophysiological and behavioral measures of face processing (i.e., orientation and species) and thus reveal a novel, objective, and non-invasive method for studying face perception.
Assuntos
Expressão Facial , Percepção de Forma/fisiologia , Orientação/fisiologia , Pupila/fisiologia , Acuidade Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação LuminosaRESUMO
Dual oxidase 1 (DUOX1) is an oxidant-generating enzyme within the airway epithelium that participates in innate airway host defense and epithelial homeostasis. Recent studies indicate that DUOX1 is suppressed in lung cancers by epigenetic silencing, although the importance of DUOX1 silencing in lung cancer development or progression is unknown. Here we show that loss of DUOX1 expression in a panel of lung cancer cell lines is strongly associated with loss of the epithelial marker E-cadherin. Moreover, RNAi-mediated DUOX1 silencing in lung epithelial cells and the cancer cell line NCI-H292 was found to result in loss of epithelial characteristics/molecular features (altered morphology, reduced barrier function and loss of E-cadherin) and increased mesenchymal features (increased migration, anchorage-independent growth and gain of vimentin/collagen), suggesting a direct contribution of DUOX1 silencing to epithelial-to-mesenchymal transition (EMT), an important feature of metastatic cancer. Conversely, overexpression of DUOX1 in A549 cells was capable of reversing EMT features. DUOX1 silencing in H292 cells also led to enhanced resistance to epidermal growth factor receptor tyrosine kinase inhibitors such as erlotinib, and enhanced levels of cancer stem cell (CSC) markers CD133 and ALDH1. Furthermore, acquired resistance of H292 cells to erlotinib resulted in enhanced EMT and CSC features, as well as loss of DUOX1. Finally, compared with control H292 cells, H292-shDUOX1 cells displayed enhanced invasive features in vitro and in vivo. Collectively, our findings indicate that DUOX1 silencing in lung epithelial cancer cells promotes features of EMT, and may be strongly associated with invasive and metastatic lung cancer.
RESUMO
Previous studies demonstrating changes in women's face preferences have emphasized increased attraction to cues to possible indirect benefits (e.g. heritable immunity to infection) that coincides with periods of high fertility (e.g. the late follicular phase of the menstrual cycle). By contrast, here we show that when choosing between composite faces with raised or lowered apparent health, women's preferences for faces that are perceived as healthy are (i) stronger during the luteal phase of the menstrual cycle than during the late follicular, fertile phase, (ii) stronger in pregnant women than in non-pregnant women and (iii) stronger in women using oral contraceptives than in women with natural menstrual cycles. Change in preference for male faces was greater for short- than long-term relationships. These findings indicate raised progesterone level is associated with increased attraction to facial cues associated with possible direct benefits (e.g. low risk of infection) and suggest that women's face preferences are influenced by adaptations that compensate for weakened immune system responses during pregnancy and reduce the risk of infection disrupting foetal development.
Assuntos
Beleza , Comportamento de Escolha/fisiologia , Anticoncepcionais Orais/farmacologia , Face , Ciclo Menstrual/fisiologia , Análise de Variância , Comportamento de Escolha/efeitos dos fármacos , Feminino , Nível de Saúde , Humanos , Ciclo Menstrual/psicologia , Gravidez , Psicofisiologia , Reino UnidoRESUMO
Exaggerated sexual dimorphism and symmetry in human faces have both been linked to potential 'good-gene' benefits and have also been found to influence the attractiveness of male faces. The current study explores how female self-rated attractiveness influences male face preference in females using faces manipulated with computer graphics. The study demonstrates that there is a relatively increased preference for masculinity and an increased preference for symmetry for women who regard themselves as attractive. This finding may reflect a condition-dependent mating strategy analogous to behaviours found in other species. The absence of a preference for proposed markers of good genes may be adaptive in women of low mate value to avoid the costs of decreased parental investment from the owners of such characteristics.
Assuntos
Beleza , Comportamento de Escolha/fisiologia , Face , Autoimagem , Caracteres Sexuais , Adolescente , Adulto , Gráficos por Computador , Corte , Assimetria Facial , Feminino , Humanos , Masculino , FenótipoRESUMO
Secondary sexual characteristics may indicate quality of the immune system and therefore a preference for masculinity may confer genetic benefits to offspring; however, high masculinity may be associated with costs of decreased paternal investment. The current study examined women's preferences for masculinity in male faces by using computer graphics to allow transformation between feminine and masculine versions of individual male faces. We found that preferences for masculinity are increased when women either have a partner or are considering a short-term relationship. Such preferences are potentially adaptive, serving to: (i) maximize parental investment and cooperation in long-term relationships by biasing choices towards feminine faced males, and (ii) maximize possible good-gene benefits of short-term or extra-pair partners by biasing choices towards masculine faced males. We also found that individuals using oral contraception do not show the above effects, indicating that such hormonal intervention potentially disrupts women's choices for evolutionarily relevant benefits from males.
Assuntos
Comportamento de Escolha/fisiologia , Face/fisiologia , Caracteres Sexuais , Adolescente , Adulto , Gráficos por Computador , Anticoncepcionais Orais Hormonais , Características da Família , Feminino , Humanos , Masculino , Fatores de TempoRESUMO
Facial symmetry has been proposed as a marker of developmental stability that may be important in human mate choice. Several studies have demonstrated positive relationships between facial symmetry and attractiveness. It was recently proposed that symmetry is not a primary cue to facial attractiveness, as symmetrical faces remain attractive even when presented as half faces (with no cues to symmetry). Facial sexual dimorphisms ('masculinity') have been suggested as a possible cue that may covary with symmetry in men following data on trait size/symmetry relationships in other species. Here, we use real and computer graphic male faces in order to demonstrate that (i) symmetric faces are more attractive, but not reliably more masculine than less symmetric faces and (ii) that symmetric faces possess characteristics that are attractive independent of symmetry, but that these characteristics remain at present undefined.
Assuntos
Face/fisiologia , Caracteres Sexuais , Assimetria Facial , Humanos , MasculinoRESUMO
Dietary sodium restriction is increasingly regarded as important in the prevention and treatment of essential hypertension. However, low-sodium diets are frequently considered unpalatable and therefore unfeasible. The objectives of this study were to determine (a) whether hypertensives, treated and untreated, differ in saltiness taste perception from age-matched normotensive controls and (b) whether sodium reduction can be accomplished by substituting another taste stimulus without reducing apparent saltiness and palatability. Subjects included 72 hypertensives, 44 to 69 years old, divided among three treatment groups; 25 age-matched normotensive controls; and an additional 21 normotensives, 20 to 43 years old, to provide an age continuum for evaluating age effects. Taste responses were measured in terms of saltiness intensity and preference using tomato juice varying systematically in sodium chloride and citric acid content. No significant differences were found between normotensives and hypertensives. No significant effects were associated with blood pressure status, therapeutic regimen, age, sex, race, or anthropometric measurements. Both sodium chloride and citric acid were main effects for saltiness, allowing a trade-off between salt and acid. Addition of citric acid permitted 50% reduction of sodium content in tomato juice without disturbing palatability criteria. Results provide a model for modifying other processed foods.
Assuntos
Dieta Hipossódica , Preferências Alimentares , Hipertensão/dietoterapia , Cloreto de Sódio , Paladar , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Fatores Etários , Idoso , Antropometria , Pressão Sanguínea , Citratos , Ácido Cítrico , Diuréticos/farmacologia , Diuréticos/uso terapêutico , Estudos de Avaliação como Assunto , Feminino , Humanos , Concentração de Íons de Hidrogênio , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Paladar/efeitos dos fármacos , VerdurasRESUMO
Responses to changes in salt and acid concentration in experimentally prepared tomato juice samples were examined in young and aging adults. Results indicated that perceived saltiness intensity and taste preference ratings were strongly affected by both salt and acid concentration. Addition of acid increased the salt intensity ratings at all salt levels, including the unsalted samples, indicating that the apparent saltiness of the tomato juice was increased by the addition of acid alone. The highest taste preference rating occurred near the 0.6% salt level, with no added acid (equivalent to commercial tomato juice); however, the taste preference rating for the 0.3% salt, 0.3% citric acid sample was not significantly different from that of the higher salt, no added acid sample. Saltiness intensity was similar for the two samples. This offers compelling evidence that a trade-off can be accomplished by substituting acid for some of the salt in tomato juice without affecting its palatability or apparent saltiness, thus providing an acceptable solution for those desiring to limit salt intake. While marked lessening of ability to make discriminations occurred only in the oldest subjects, they showed no evidence of distortion in preference but tended to accept those samples most preferred by the younger subjects.
Assuntos
Bebidas , Cloreto de Sódio , Paladar , Verduras , Adulto , Fatores Etários , Idoso , Citratos , Ácido Cítrico , Feminino , Aditivos Alimentares , Preferências Alimentares , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Fatores SexuaisRESUMO
In some species, female condition correlates positively with preferences for male secondary sexual traits. Women's preferences for sexually dimorphic characteristics in male faces (facial masculinity) have recently been reported to covary with self-reported attractiveness. As women's attractiveness has been proposed to signal reproductive condition, the findings in human (Homo sapiens) and other species may reflect similar processes. The current study investigated whether the covariation between condition and preferences for masculinity would generalize to 2 further measures of female attractiveness: other-rated facial attractiveness and waist-to-hip ratio (WHR). Women with high (unattractive) WHR and/or relatively low other-rated facial attractiveness preferred more "feminine" male faces when choosing faces for a long-term relationship than when choosing for a short-term relationship, possibly reflecting diverse tactics in female mate choice.
Assuntos
Comportamento de Escolha , Expressão Facial , Percepção de Forma , Identidade de Gênero , Caracteres Sexuais , Adulto , Beleza , Constituição Corporal , Feminino , Humanos , Masculino , Casamento , Autoavaliação (Psicologia) , Comportamento SexualRESUMO
The purpose of this study is to investigate an earlier finding wherein more than 100 subjects in four age groups responded systematically but differently to Munsell hues. According to the theoretical construction of the Munsell Color System, the spacing of the 10 hues is in perceptually equal intervals; the error responses to all hues at constant chroma should therefore be equal. The mean error rates were compared with Munsell hue distribution on seven linear and non-linear transformations of the International Commission on Illumination chromaticity diagram to uniform chromaticity systems. Hue intervals are not equal: red and green have the smallest intervals and largest error, and yellow and yellow-red the largest intervals and smallest error rate. These observations were substantiated by results from multidimensional scaling experiments reported elsewhere.
Assuntos
Percepção de Cores , Cor , Discriminação Psicológica , Criança , Testes de Percepção de Cores , Humanos , Modelos PsicológicosRESUMO
Acute alcohol consumption increases ratings of attractiveness to faces. This may help to explain increased frequencies of sexual encounters during periods of alcohol intoxication. At least in part, such increased attraction may be the result of alcohol consumption decreasing ability to detect bilateral asymmetry, presumably because of the reductions in the levels of visual function. We tested the hypotheses that acute alcohol consumption decreases ability to detect asymmetry in faces and reduces preference for symmetrical faces over asymmetrical faces. Twenty images of a pair of faces and then 20 images of a single face were displayed on a computer, one at a time. Participants were instructed to state which face of each of the face pairs displayed was most attractive and then whether the single face being displayed was symmetrical or not. Data were collected near campus bars at Roehampton University. Sixty-four self-selecting students who undertook the study were classified as either sober (control) or intoxicated with alcohol. For each face pair or single face displayed, participant response was recorded and details of the alcohol consumption of participants that day were also obtained. Sober participants had a greater preference for symmetrical faces and were better at detecting whether a face was symmetrical or otherwise, supporting the hypotheses. A further, unexpected finding was that males made fewer mistakes than did females when determining whether individual faces were asymmetrical. The reduced ability of inebriated people to perceive asymmetry may be an important mechanism underlying the higher ratings of facial attractiveness they give for members of the opposite sex and hence their increased frequency of mate choice.
Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Intoxicação Alcoólica/psicologia , Beleza , Assimetria Facial/psicologia , Percepção Visual , Adolescente , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Comportamento Sexual/psicologia , Adulto JovemAssuntos
Cor , Corantes , Aditivos Alimentares , Carotenoides , Clorofila , Alcatrão , Heme , Legislação de Medicamentos , Magnésio , Pirróis , Estados UnidosRESUMO
Women's preferences for masculinity in men's faces, voices and behavioral displays change during the menstrual cycle and are strongest around ovulation. While previous findings suggest that change in progesterone level is an important hormonal mechanism for such variation, it is likely that changes in the levels of other hormones will also contribute to cyclic variation in masculinity preferences. Here we compared women's preferences for masculine faces at two points in the menstrual cycle where women differed in salivary testosterone, but not in salivary progesterone or estrogen. Preferences for masculinity were strongest when women's testosterone levels were relatively high. Our findings complement those from previous studies that show systematic variation in masculinity preferences during the menstrual cycle and suggest that change in testosterone level may play an important role in cyclic shifts in women's preferences for masculine traits.
Assuntos
Beleza , Face , Saliva/química , Comportamento Sexual/fisiologia , Testosterona/metabolismo , Adolescente , Adulto , Feminino , Humanos , Masculino , Projetos Piloto , Desejabilidade SocialRESUMO
Previous studies of changes in women's behavior during the menstrual cycle have offered insight into the motivations underpinning women's preferences for social cues associated with possible direct benefits (e.g., investment, low risk of infection) and indirect benefits (e.g., offspring viability). Here we sought to extend this work by testing for systematic variation in women's preferences for male and female faces and in their attitudes to their romantic relationship during the menstrual cycle. In Study 1, we found partnered women's reported commitment to their romantic relationship and preferences for femininity in male and female faces were strongest on days of the menstrual cycle when progesterone levels are increased (and fertility is low). Happiness in relationships did not change across the cycle. In Study 2, we found that the effect of cycle phase on women's preference for feminine faces was independent of increased attraction to apparent health in faces during the luteal phase. Collectively, these findings are further evidence that women's preferences for social cues associated with possible direct benefits and commitment to relationships are strongest during conditions characterized by raised progesterone level, while attraction to men displaying cues associated with possible indirect benefits is strongest when women are most fertile.
Assuntos
Beleza , Identidade de Gênero , Ciclo Menstrual/sangue , Ciclo Menstrual/psicologia , Progesterona/sangue , Comportamento Sexual/psicologia , Adulto , Afeto/fisiologia , Análise de Variância , Comportamento de Escolha/fisiologia , Face , Feminino , Nível de Saúde , Humanos , Masculino , Reconhecimento Visual de Modelos/fisiologia , Fatores Sexuais , Comportamento Sexual/fisiologiaRESUMO
Based on Farnsworth's theories of color confusion and discrimination, "rose-colored" or "pink" filters such as the X-Chrom material of 0.16 mm in thickness or the Kodak Wratten no. 30 filter act as monocular chromatic enhancers for red/green color deficients by virtue of colorimetrically lengthening color space in a direction perpendicular to the dichromatic axis of color confusion. Using derived formulas for dichromat colorimetry, a set of representative isoluminant-isochroma spectral hues, and interactive computer graphic colorimetric tools, it is possible to determine an optimum spectrophotometric filter curve. Such a filter has minimal middle wavelength transmission and is optimal in terms of providing maximal monocular chromatic clues for discriminative tasks involving confused colors.