Ontogeny of sex differences in defensive burying behavior in rats: effect of social isolation

The aim of the present experiments was to clarify sex differences in socio-developmental factors that affected defense behavior in rats. Sex differences in the defensive burying behavior of rats, and related social factors, were explored in three developmental stages: juvenile, puberty, and adult; 30, 50, and 80 days of age, respectively. The duration of burying, digging into bedding material, stretch-attend postures, and crouch/freezing were measured in a shock-prod test. For males, the duration of burying was longer in the juvenile and pubertal stages than in adulthood. For females, no age differences in the duration of burying were found. Males showed longer burying durations than females in both the juvenile and pubertal stages. For both sexes, the highest duration of digging was found in the juvenile stage, and females showed longer durations of digging than males. Both male and female rats isolated during the juvenile stage, from 26 to 40 days of age, showed smaller durations of burying behavior compared to pair-reared rats. This effect of juvenile isolation was maintained among both adult males and females even when they were returned to pair rearing after isolation. Isolation during adulthood, from 66 to 80 days of age, increased burying behavior in males, but decreased it in females. The durations of digging, stretch-attend postures, and crouch/freezing were not affected by isolation. The decrease in defensive burying and its increase resulting from isolation in adult male rats, suggest that the emergence of adult-like social relationships in males suppressed the duration of burying. Male and female rats isolated during the juvenile stage maintained lower levels of burying, suggesting that social experience as juveniles is important for the emergence of defensive burying behavior.     

损毁大鼠双侧内嗅皮质对束缚应激反应的影响

采用大鼠急性束缚应激动物模型,用鹅羔氨酸损毁大鼠双侧内嗅皮质来建立内嗅皮质损伤模型,观察束缚应激1小时后下丘脑室旁核快反应基因c-Fos表达情况以及应激后血浆促肾上腺皮质激素含量的动态变化,并与对照组相比较,探讨内嗅皮质与束缚应激反应的关系。结果表明,损毁内嗅皮质,明显抑制了应激诱导的下丘脑室旁核c-Fos的表达和血浆促肾上腺皮质激素含量的上升。结果提示,内嗅皮质参与调节束缚应激反应时HPA轴功能。     

The perception of an opening from expanding motion

The ability of humans to detect an opening’s 3-D structure from expanding motion was tested. Computer simulations of dotted tunnels were used to generate optical flows typically encountered when one moves through an opening. Experiment 1 qualitatively tested the ability to detect the shape of a tunnel’s vertical section. The observers could choose the correct shape for each of seven simulated shapes. The percentages of correct responses were much higher than those under static conditions. Experiment 2 tested whether or not one could quantitatively detect the vertical-horizontal proportion of the elliptic tunnels. The result shows quite high correlations (r = .93≈.97) between perceived proportions and simulated ones. The slopes of the regression lines were around 1.0. Experiment 3 investigated the necessary stimulus duration for detecting an opening’s shape. Relative size (width and height) was significantly detected under four-frame (72.7-msec) conditions by 3 out of 4 subjects. The other subject performed well under eight-frame conditions. These results indicate that the human visual system can instantly detect the 3-D structure of an opening surrounded by objects from expanding optical flows while one is in forward motion.     

The effect of odors on human newborn infants under stress

Five-day-old human infants' responses to heelstick stress were assessed with behavioral and physiological indices. The subjects were divided randomly into three groups: the LAV group, who were presented with artificial odor of lavender during the heelstick; the MILK group, who were presented with artificial odor of milk during the heelstick; and the CONT group, who were presented with no special odors. The CONT group showed more adrenocortisol release in saliva than the other groups, but there were no differences between the two odors.     

Intuitive control of mobile robots: an architecture for autonomous adaptive dynamic behaviour integration

In this paper, we present a novel approach to human–robot control. Taking inspiration from behaviour-based robotics and self-organisation principles, we present an interfacing mechanism, with the ability to adapt both towards the user and the robotic morphology. The aim is for a transparent mechanism connecting user and robot, allowing for a seamless integration of control signals and robot behaviours. Instead of the user adapting to the interface and control paradigm, the proposed architecture allows the user to shape the control motifs in their way of preference, moving away from the case where the user has to read and understand an operation manual, or it has to learn to operate a specific device. Starting from a tabula rasa basis, the architecture is able to identify control patterns (behaviours) for the given robotic morphology and successfully merge them with control signals from the user, regardless of the input device used. The structural components of the interface are presented and assessed both individually and as a whole. Inherent properties of the architecture are presented and explained. At the same time, emergent properties are presented and investigated. As a whole, this paradigm of control is found to highlight the potential for a change in the paradigm of robotic control, and a new level in the taxonomy of human in the loop systems.     

The neural correlates of driving performance identified using positron emission tomography

Driving is a complex behavior involving multiple cognitive domains. To identify neural correlates of driving performance, [15O]H2O positron emission tomography was performed using a simulated driving task. Compared with the resting condition, simulated driving increased regional cerebral blood flow (rCBF) in the cerebellum, occipital, and parietal cortices. Correlations between rCBF and measurements of driving performance were evaluated during simulated driving. Interestingly, rCBF in the thalamus, midbrain, and cerebellum were positively correlated with time required to complete the course and rCBF in the posterior cingulate gyrus was positively correlated with number of crashes during the task. These brain regions may thus play roles in the maintenance of driving performance.     

Prospective cohort study of stress, life satisfaction, self-rated health, insomnia, and suicide death in Japan

The association between many psychosocial factors and risk of suicide was examined. A cohort was conducted over 14 years of follow up among the general population (15,597 people) in Japan. A baseline survey of psychosocial characteristics was conducted by self-administrated questionnaire. The relative risks of occasional emotional stress, difficulty maintaining sleep, and reporting unhealthy as their self-rated health are 3.2 (95% CI: 1.3, 7.6), 2.4 (95% CI: 1.3, 4.3) and 2.6 (95% CI: 1.1, 6.2), respectively. The importance of these observations lie in its potential for improving physician and public awareness of psychosocial factors as an early indication of mental health morbidity.     

Rapid image-segmentation and perceptual transparency share a process which utilises X-junctions generated by temporal integration in the visual system

Perceptual transparency requires local same-polarity X-junctions, which can also be generated by temporal integration under natural dynamic conditions. In this study, segmentation performance and target appearance were measured for a uniform gray target embedded in a random-dot frame presented with a temporally adjacent mask. Although static cues for both segmentation and transparency were unavailable, transparency was observed only when collinear same-polarity edges reduced backward masking, in both the fovea and the perifovea. These results suggest that the visual system has a common underlying mechanism for rapid segmentation and transparency, which utilises same-polarity X-junctions generated by temporal integration.     

Demonstrating a wordlikeness effect on nonword repetition performance in a conduction aphasic patient

The purpose of this study was to identify the nature of the deficit for a conduction aphasic patient in order to evaluate two different theories of conduction aphasia. First, a conduction aphasic patient FS was tested on auditory word-pair discrimination, word-repetition, and picture-naming. The results of these tasks indicated that her deficit was likely to be post-lexical rather than perceptual or lexical. Next, we examined her repetition performance for two types of nonwords (high-wordlike and low-wordlike nonwords) to distinguish the two theories. FS exhibited a wordlikeness effect: she produced more correct moras and more correct combinations of moras for high-wordlike nonwords than low-wordlike nonwords. We conclude that she had difficulty in maintaining stable phonological representations of verbal materials in the output buffer.