小鼠对不同拓扑性质图形的识别

视觉感知的一系列研究都支持大范围拓扑感知的理论．拓扑性质作为整体性质,是视觉感知的基础．视觉对图形拓扑特征差异的感知要优先于对局部特征差异的感知．采用Y迷宫研究了小鼠对不同拓扑性质图形的识别．训练小鼠学习识别圆环和实心矩形这一对拓扑性质不同的图形,之后用拓扑特征相同或不同的其他图形测试小鼠,这些图形包括空心矩形、实心圆、缺口的圆环、缺口的空心矩形．实验结果表明,学会识别圆环(奖励)和实心矩形(无奖励)的小鼠无法区分实心圆和实心矩形以及圆环和空心矩形,但是能够分别从缺口圆环、缺口的空心矩形、实心圆与空心矩形组成的图形对中识别出空心矩形．因此证实了小鼠的视觉系统能够感知拓扑特征的差异并且具有对拓扑性质的概括能力．结果为拓扑知觉对视觉系统来说是基本的这一假设提供了证据．     

Raised salivary testosterone in women is associated with increased attraction to masculine faces

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.     

Artificial neural networks and the study of evolution of prey coloration

In this paper, I investigate the use of artificial neural networks in the study of prey coloration. I briefly review the anti-predator functions of prey coloration and describe both in general terms and with help of two studies as specific examples the use of neural network models in the research on prey coloration. The first example investigates the effect of visual complexity of background on evolution of camouflage. The second example deals with the evolutionary choice of defence strategy, crypsis or aposematism. I conclude that visual information processing by predators is central in evolution of prey coloration. Therefore, the capability to process patterns as well as to imitate aspects of predator's information processing and responses to visual information makes neural networks a well-suited modelling approach for the study of prey coloration. In addition, their suitability for evolutionary simulations is an advantage when complex or dynamic interactions are modelled. Since not all behaviours of neural network models are necessarily biologically relevant, it is important to validate a neural network model with empirical data. Bringing together knowledge about neural networks with knowledge about topics of prey coloration would provide a potential way to deepen our understanding of the specific appearances of prey coloration.     

Levels of processing during non-conscious perception: a critical review of visual masking

Understanding the extent and limits of non-conscious processing is an important step on the road to a thorough understanding of the cognitive and cerebral correlates of conscious perception. In this article, we present a critical review of research on subliminal perception during masking and other related experimental conditions. Although initially controversial, the possibility that a broad variety of processes can be activated by a non-reportable stimulus is now well established. Behavioural findings of subliminal priming indicate that a masked word or digit can have an influence on perceptual, lexical and semantic levels, while neuroimaging directly visualizes the brain activation that it evokes in several cortical areas. This activation is often attenuated under subliminal presentation conditions compared to consciously reportable conditions, but there are sufficiently many exceptions, in paradigms such as the attentional blink, to indicate that high activation, per se, is not a sufficient condition for conscious access to occur. We conclude by arguing that for a stimulus to reach consciousness, two factors are jointly needed: (i) the input stimulus must have enough strength (which can be prevented by masking) and (ii) it must receive top-down attention (which can be prevented by drawing attention to another stimulus or task). This view leads to a distinction between two types of non-conscious processes, which we call subliminal and preconscious. According to us, maintaining this distinction is essential in order to make sense of the growing neuroimaging data on the neural correlates of consciousness.     

The role of temporal generalization in a temporal discrimination task

Two experiments trained rats to discriminate two or three stimulus durations using a temporal discrimination task. A standard peak shift effect was observed when training was administered with short versus long signals in Experiment 1. Both discrimination accuracy scores and the generalization gradients revealed that shorter intervals were discriminated more accurately, which may be due to the scalar property of timing. In Experiment 2, three signals (short, medium, and long) were associated with three different responses, or two of the intervals were associated with one response (short and long or short and medium) and the other interval with a different response. Here, the short/medium versus long discrimination was learned most readily of the three tasks. The results of both experiments indicated a strong contribution of learning of individual durations combined with scalar generalization gradients, but Experiment 2 indicated that categorical encoding of durations may have also been operating.     

Positive implicit attitudes toward odor words

Associations between certain odors and for instance health effects may lead to positive or negative attitudes toward these odors. However, in experiments we conducted using the Implicit Association Test (IAT), we encountered attitudes even to odor "words." The IAT is based on the principle that reaction times measuring the association between words from a target dimension (in this case, odor vs. a neutral reference category) and an attribute dimension (i.e., positive or negative words) reflect the attitude to the target, where attitude-congruent associations between target and attribute are reflected by shorter reaction times. In a first experiment, we found distinctly positive attitudes to the concept odor in a student sample, which was replicated in a second experiment. In the main experiment, subjects in the aromatherapy group, who prefer using scented consumer products for relaxation purposes, showed a significantly more positive attitude toward odor words in the IAT than a control group, who did not have such a preference. The fact that results from the implicit test were not always associated with explicitly stated attitudes toward the odor words attests to the fact that the IAT measures the attitude of interest in a different way. As such, the IAT has added value in circumstances where explicit tests can be biased.     

Culpa por percibirse como una carga. Una variable relevante asociada al malestar psicológico de las personas mayores

AimsTo analyze the relationship between guilt for perceiving oneself as a burden and negative self-perceptions of aging, perceived control and anxious and depressive symptomatology in older people without cognitive or functional limitations.MethodsParticipants were 351 community-dwelling people over 60 years without explicit cognitive or functional limitation. Indirect effet analysis were conducted that examined the indirect effect of negative self-perceptions of aging through 1) perceived control and anxious symptomatology and 2) perceived control and depressive symptomatology in guilt for perceiving oneself as a burden.ResultsBoth models showed an indirect relationship between negative self-perceptions of aging and guilt for perceiving oneself as a burden through 1) perceived control and anxious symptomatology and 2) perceived control and depressive symptomatology, explaining 26.37% of anxious symptomatology, 48.51% of depressive symptomatology and 13.73% and 14.44% of guilt for perceiving oneself as a burden, respectively.DiscussionThe results obtained suggest that higher negative self-perceptions of aging is associated with a lower perception of control and greater psychological distress (anxiety and depression), and this process increases the feeling of guilt for perceiving oneself as burden to family members in older people without functional or cognitive limitations.     

Freedom of religion,women's agency and banning the face veil: the role of feminist beliefs in shaping women's opinion

Several countries have imposed bans on the wearing of face veils, a controversial option considered in Bill 94 by the province of Quebec in 2010. This paper examines non-Muslim women's support for the acceptability of the niqab in public spaces. Analysing the 2010 Quebec Women's Political Participation Survey, we find that key feminist arguments – that wearing the niqab is a woman's free choice, a matter of freedom of religion and a visible symbol of women's oppression – are important drivers of opinion. Their role in shaping opinion, however, is complex and mirrors divisions among feminist groups in the province. Additional attitudinal drivers include generation, exposure to the practice and openness to immigration. Equally important, our findings suggest that being a member of a racial minority, feelings of cultural insecurity and religiosity are of little consequence for thinking on the issue.