It is established that stress impairs spatial learning and memory via the hypothalamus-pituitary-adrenal axis response. Dopamine D1 receptors were also shown to be responsible for a stress-induced deficit of working memory. However, whether stress affects the subsequent emotional learning and memory is not elucidated yet. Here, we employed the well-established one-trial step-through task to study the effect of an acute psychological stress (induced by tail hanging for 5, 10, or 20?min) on emotional learning and memory, and the possible mechanisms as well. We demonstrated that tail hanging induced an obvious stress response. Either an acute tail-hanging stress or a single dose of intraperitoneally injected dopamine D1 receptor antagonist (SCH23390) significantly decreased the step-through latency in the one-trial step-through task. However, SCH23390 prevented the acute tail-hanging stress-induced decrease in the step-through latency. In addition, the effects of tail-hanging stress and/or SCH23390 on the changes in step-through latency were not through non-memory factors such as nociceptive perception and motor function. Our data indicate that the hyperactivation of dopamine D1 receptors mediated the stress-induced deficit of emotional learning and memory. This study may have clinical significance given that psychological stress is considered to play a role in susceptibility to some mental diseases such as depression and post-traumatic stress disorder. 相似文献
Bilingual speakers generally manifest slower word recognition than monolinguals. We investigated the consequences of the word processing speed on semantic access in bilinguals. The paradigm involved a stream of English words and pseudowords presented in succession at a constant rate. English-Welsh bilinguals and English monolinguals were asked to count the number of letters in pseudowords and actively disregard words. They were not explicitly told that pairs of words in immediate succession were embedded and could either be semantically related or not. We expected that slower word processing in bilinguals would result in semantic access indexed by semantic priming. As expected, bilinguals showed significant semantic priming, indexed by an N400 modulation, whilst monolinguals did not. Moreover, bilinguals were slower in performing the task. The results suggest that bilinguals cannot discriminate between pseudowords and words without accessing semantic information whereas monolinguals can dismiss English words on the basis of subsemantic information. 相似文献
In this research we examine the effect of adding a food topping to the base food on consumers' calorie estimation and consumption of the augmented food (base food plus topping). We show that consumers underestimate the calorie content of augmented food with an unhealthy base, especially when the topping is healthy. However, consumers are less likely to underestimate the calorie content of augmented food with a healthy base, regardless of whether the topping is healthy or unhealthy. Further, we show that adding a healthy topping to an unhealthy base makes consumers not only underestimate the calorie content but also eat more of the augmented food. 相似文献
In previous studies, a physical response-distance effect was found in the two-choice Stroop color-identification task, with the Stroop effect being larger when the two response keys were physically close together than when they were far apart. In the present study, we found a conceptual response-distance effect, with the Stroop effect being larger when the response keys were conceptually close (labeled as “5” and “6”) than when they were conceptually far (labeled as “1” and “9”). Moreover, a response-distance effect due to pure physical distance was not evident; rather, the effect was found only when additional keys were placed between the two far response keys. These results are in agreement with a view that response keys are coded as action goals, with farther conceptual distance and additional keys helping distinguish the action goals. The results are difficult to reconcile with accounts that place emphasis on the physical separation of the effectors or their inanimate extensions. 相似文献
It has become increasingly common for young children to be taken care of by multiple caregivers in China after the socio-economic reforms. Complex migration patterns and high female labour force participation have led to children receiving care from various individuals in different contexts. However, little is known about how childcare arrangements are associated with child health well-being. This study examines various early childhood caregivers and their influences on children’s physical health in China. Using data from the China Health and Nutrition Survey (CHNS 1991–2011) with 3,470 children aged 2 to 6, we first identified different types of childcare arrangements in and outside of the household based on who provides the care, where they provide the care, and the intensity of the care. Then we examined the relationship between various childcare arrangements and health outcomes for children. Overall, household members undertook early childhood care tasks in China, with an increase in grandparents as primary caregivers between 1991 and 2011. The proportion of children receiving formal childcare fluctuated around 20% during this period. The findings suggest that: 1) primary caregiver in the household other than parents is not associated with undesirable physical health outcomes; 2) formal childcare outside the household is associated with higher height and lower BMI scores; 3) primary caregivers in the household, particular grandparents, moderate the association between childcare arrangements outside the household and children’s health outcomes. It yields an implication that early childhood care policies incorporating multiple caregivers would benefit children’s well-being in China.