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981.
982.
983.
Three experiments are reported that collectively show that listeners perceive speech sounds as contrasting auditorily with neighboring sounds. Experiment 1 replicates the well-established finding that listeners categorize more of a [d–g] continuum as [g] after [l] than after [r]. Experiments 2 and 3 show that listeners discriminate stimuli in which the energy concentrations differ in frequency between the spectra of neighboring sounds better than those in which they do not differ. In Experiment 2, [alga–arda] pairs, in which the energy concentrations in the liquid-stop sequences are H(igh) L(ow)–LH, were more discriminable than [alda–arga] pairs, in which they are HH–LL. In Experiment 3, [da] and [ga] syllables were more easily discriminated when they were preceded by lower and higher pure tones, respectively—that is, tones that differed from the stops’ higher and lower F3 onset frequencies—than when they were preceded by H and L pure tones with similar frequencies. These discrimination results show that contrast with the target’s context exaggerates its perceived value when energy concentrations differ in frequency between the target’s spectrum and its context’s spectrum. Because contrast with its context does more that merely shift the criterion for categorizing the target, it cannot be produced by neural adaptation. The finding that nonspeech contexts exaggerate the perceived values of speech targets also rules out compensation for coarticulation by showing that their values depend on the proximal auditory qualities evoked by the stimuli’s acoustic properties, rather than the distal articulatory gestures.  相似文献   
984.
Perceptual hysteresis can be defined as the enduring influence of the recent past on current perception. Here, hysteresis was investigated in a basic auditory task: pitch comparisons between successive tones. On each trial, listeners were presented with pairs of tones and asked to report the direction of subjective pitch shift, as either “up” or “down.” All tones were complexes known as Shepard tones (Shepard, 1964), which comprise several frequency components at octave multiples of a base frequency. The results showed that perceptual judgments were determined both by stimulus-related factors (the interval ratio between the base frequencies within a pair) and by recent context (the intervals in the two previous trials). When tones were presented in ordered sequences, for which the frequency interval between tones was varied in a progressive manner, strong hysteresis was found. In particular, ambiguous stimuli that led to equal probabilities of “up” and “down” responses within a randomized context were almost fully determined within an ordered context. Moreover, hysteresis did not act on the direction of the reported pitch shift, but rather on the perceptual representation of each tone. Thus, hysteresis could be observed within sequences in which listeners varied between “up” and “down” responses, enabling us to largely rule out confounds related to response bias. The strength of the perceptual hysteresis observed suggests that the ongoing context may have a substantial influence on fundamental aspects of auditory perception, such as how we perceive the changes in pitch between successive sounds.  相似文献   
985.
986.
South Africa has one of the highest HIV infection rates in the world, with young people particularly affected. Condoms are an effective preventative method against HIV among sexually active adults. This study assessed the level of condom usage among university students in South Africa and their attitudes towards condom usage, negotiation efficacy and confidence in condom usage. It was a cross-sectional study conducted amongst South African university students living at the university residences. Students were randomly selected and required to complete a self-administered questionnaire. The mean age of participants (n?=?441) was 22.7?±?4.3 years. The mean age of sexual debut was 17.7?±?3.0 years with 1.4?±?1.47 (range 0–13) current partners. Less than half of the students used a condom at sexual debut and only 28.5% used condoms during recent sexual activity. Those students who used a condom at first sexual intercourse had marginally more positive attitudes about condom usage than those who did not do so (p?=?0.056). Students with a single current partner had more positive attitudes about condom usage than those with multiple current partners (p?=?0.021). Only 32.5% (n?=?127) of the students were very confident in using condoms. Similarly, only 33.0% (n?=?130) of the participants felt that they could definitely negotiate condom use with their partners. We conclude that condom use among South African students is low and that they lack the confidence to use condoms. We recommend that programmes to step up condom use must also incorporate educational interventions on usage.  相似文献   
987.
This study is based on exploring the trust between peers and the individual characteristics related to homophobic bullying in adolescence. Participants were 334 adolescents (141 boys and 193 girls) aged from 15 to 20 years. Participants completed the homophobic bullying scale, to investigate bullying actions towards sexual minorities, the personal attributes questionnaire, for personal characteristics, and the inventory of parent and peer attachment, to the trust between peers. The results demonstrated how female participants manifested a higher level of interpersonal traits and trust among peers than boys. Results showed how a lack of trust between peers predicts homophobic bullying. Nevertheless, we found that the lack of interpersonal characteristics represents a variable that likely mediates the relationship between lack of trust in peers and homophobic bullying. Theoretical and practical implications are discussed.  相似文献   
988.
Sexual and gender identity development theories in psychology and sociology exert considerable influence over discourse on gender and sexuality, shaping key domains such as counseling, education, and social work, as well as public policy and advocacy. While a robust body of literature has developed in critique of such theories and models, they continue to be applied in the Global South without much thought for their relevance to various non-Western cultural contexts. The current study explores the fit of these identity development theories to the experiences of 15 non-heterosexual and transgender individuals in Sri Lanka, gathered through a qualitative study of the question in 2016. These participants articulated gender and sexual self-conceptions that were incongruent with major identity development theories in significant ways. A broad majority failed to endorse central or salient sexual identities, while demonstrating a fluidity in object choice, sex roles, and sex acts, thus rupturing the theoretical notion of stable and coherent identities. Transgender participants did not demonstrate identity synthesis or pride and complicated theoretical understandings of sexual intimacy. These findings highlight the necessity of considering individual differences and cultural contexts when studying gender and sexuality and the dangers of universalizing theories across cultural differences.  相似文献   
989.
This article deals with relationships and marriages of the Tlingit with immigrants from the Russian Empire as well as with representatives of other European and non-European peoples during the period when Alaska belonged to the Russian Empire. Matrimonial relations existed in two variants: legal, sanctified by the church, and in the form of permanent extramarital cohabitation or casual relationships. The latter variant absolutely predominated. With this, there was a sharply reflected gender imbalance, since men absolutely predominated among the immigrants, and therefore Tlingit women emerged in the role of marriage partners in the overwhelming majority of cases. A directly opposite pattern was observed in Tlingit contacts with the Athapaskans and to some extent with the Eyak. Matrimonial connections exerted influence on the workings of the Russian colonization, stimulated growth in mixed populations, and facilitated gradual acculturation of the Tlingit, along with contributing to the expansion of their ethnic territory.  相似文献   
990.
The objective of this study was to identify the perception of body image by Tunisian women and their spouses and to examine its impact on female sexuality. Our study involved 300 Tunisian women who had been married for at least 1 year and consulted in primary care medicine during the months of June and July 2016. Each participant completed a questionnaire covering four areas: women’s perception of their body, the perception of the spouses of the latter as it was reported by the participants, sexual activity, and the impact of body perception on sexual activity. The participants were satisfied with their bodies in 51% of cases. This satisfaction was associated with perceiving the body as physically attractive (p?=?0.007), young (p?=?0.047) and as a source of confidence (p?<?0.001). Compared to women dissatisfied with their bodies, those satisfied declared satisfaction of sexual desire (p?=?0.005), reaching orgasm (p?=?0.001), taking the initiative in sexual activity (p?=?0.003) and preparation for sex (p?=?0.006). Perceived satisfaction of the partner with the female body was related to a more positive sexuality in women, specifically to women’s sexual satisfaction (p?=?0.018), women taking sexual initiative (p?=?0.014) and preparation for sex (p?=?0.001). Our study indicates the important impact of a positive perception of the body image of Tunisian women by themselves and by their spouses on their sexuality. It would be interesting to consider these aspects in the management of female sexual disorders.  相似文献   
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