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111.
That similar words can prime one another is not news. However, this phenomenon can be exploited to make inferences about the organization of conceptual representations. What types of similarity matter? Although there is evidence that similarity of function, shape, and even manner of manipulation is reflected in semantic memory, evidence for organization on the basis of color similarity is sparse. This lack of evidence is surprising: Intuition suggests that color is a prominent feature of many object concepts. The research reported here clarifies this puzzle and illustrates the dynamic nature of conceptual representations. Our research demonstrates color-based priming (e.g., "emerald" primes "cucumber") in participants who completed a Stroop color-naming task before a priming task. Notably, the size of the Stroop effect predicted the size of the priming effect. When the order of tasks was reversed, priming effects were eliminated. By demonstrating that both extrinsic and intrinsic factors can influence conceptual activation, our findings have implications for theories of semantic memory.  相似文献   
112.
Prenatal exposure to alcohol may lead to a range of neurobehavioral effects, including impaired learning and memory. Although children with fetal alcohol spectrum disorders (FASD) exhibit both verbal and nonverbal memory impairments, their memory for faces has not been as thoroughly investigated and the extent literature provides inconsistent results. The aim of the current study was to determine whether difficulties in face memory exist in children with FASD and whether the difficulties are mediated by task demands. To address this, we used two measures of immediate and delayed facial recognition memory, the Children's Memory Scale (CMS) and Test of Memory and Learning (TOMAL). Compared to typically developing controls, children with FASD showed memory deficits on all tests and were more likely to perform in a clinically significant range. As well, children performed more poorly on the CMS compared to TOMAL, a finding consistent with the greater difficulty of the CMS task. Our results are consistent with our hypothesis that children with FASD show impairment in facial memory, particularly on demanding memory tasks.  相似文献   
113.
In the present study we examined, first, whether voluntary and involuntary attention manifest differently in people who differ in impulsivity (measured with the Barratt Impulsivity Scale). For Experiment 1, we used the spatial cueing task with informative and noninformative spatial cues to probe voluntary and involuntary attention, respectively. We found that participants with high impulsivity scores exhibited larger involuntary attention effects, whereas participants with low impulsivity scores exhibited larger voluntary attention effects. For Experiment 2, we used the correlated-flanker task to determine whether the differences between groups in Experiment 1 were due to high-impulsive participants being less sensitive to the display contingencies or to high-impulsive participants having a greater spread of spatial attention. Surprisingly, high-impulsive participants showed a greater sensitivity to contingencies in the environment (correlated-flanker effect). Our results illustrate one situation in which involuntary attention associated with high impulsivity can play a useful role.  相似文献   
114.
Concomitant deficits in working memory and behavioral inhibition in several psychiatric disorders like attention-deficit/hyperactivity disorder, addiction or mania, suggest that common brain mechanisms may underlie their etiologies. Based on the theoretical assumption that a continuum exists between health and mental disorders, we explored the relationship between working memory and inhibition in healthy individuals, through spontaneous inter individual differences in behavior, and tested the hypothesis of a functional link through the fronto-striatal dopaminergic system. Rats were classified into three groups, showing good, intermediate and poor working memory and were compared for their inhibitory abilities. These two functions were simultaneously modulated by a dose-effect of d-amphetamine and in situ hybridization was used to quantify dopaminergic receptor (RD1) mRNAs in prefrontal cortex and striatal areas. A functional relationship between working memory and inhibition abilities was revealed. Both functions were similarly modulated by d-amphetamine according to an inverted-U shaped relationship and depending on initial individual performances. D-amphetamine selectively improved working memory and inhibition of poor and intermediate performers at low doses whereas it impaired both processes in good performers at a higher dose. D1 receptors were less expressed in prelimbic, infralimbic and anterior cingulate cortices of good compared to intermediate and poor performers, whereas no difference was observed between groups in striatal areas. The synergy of working memory and inhibitory abilities, observed in both healthy and psychiatric populations, may originate from endogenous variability in dopaminergic prefrontal cortex activity. Such findings confirm the validity of a dimensional approach, based on the concept of continuity between health and mental disorders for identifying endophenotypes of mental disorders.  相似文献   
115.
Rodents solve dual-solution tasks that require navigation to a goal by adopting either a hippocampus-dependent place strategy or a striatum-dependent stimulus-response strategy. A variety of factors, including biological sex and emotional status, influence the choice of learning strategy. In these experiments, we investigated the relationship between learning strategy and anxiety level in male and female rats prior to the onset of puberty, before the activational effects of gonadal hormones influence these processes. In the first experiment, prepubertal male rats categorized as high in trait anxiety at 26days of age exhibited a bias toward stimulus-response strategy at 28days of age, whereas age-matched females exhibited no preference in strategy regardless of anxiety level. In the second experiment, male and female rats were separated from their dams for either 15 or 180min per day during the first 2weeks of life and tested on a battery of anxiety and cognitive tasks between 25 and 29days of age. Prolonged maternal separations for 180min were associated with impaired spatial memory on a Y-maze task in both prepubertal males and females. Furthermore, prolonged maternal separations were linked to elevated anxiety and a bias for stimulus-response strategy in prepubertal males but not females. Alternatively, brief separations from dams for 15min were associated with intact spatial memory, lower levels of anxiety, and no preference for either learning strategy in both sexes. These results provide evidence of sex-specific effects of trait anxiety and early maternal separation on the choice of learning strategy used by prepubertal rodents.  相似文献   
116.
117.
What factors determine whether mixed-race individuals claim a biracial identity or a monoracial identity? Two studies examine how two status-related factors-race and social class-influence identity choice. While a majority of mixed-race participants identified as biracial in both studies, those who were members of groups with higher status in American society were more likely than those who were members of groups with lower status to claim a biracial identity. Specifically, (a) Asian/White individuals were more likely than Black/White or Latino/White individuals to identify as biracial and (b) mixed-race people from middle-class backgrounds were more likely than those from working-class backgrounds to identify as biracial. These results suggest that claiming a biracial identity is a choice that is more available to those with higher status.  相似文献   
118.
The social brain undergoes developmental change during adolescence, and pubertal hormones are hypothesized to contribute to this development. We used fMRI to explore how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to brain activity during a social emotion task. Forty‐two females aged 11.1 to 13.7 years underwent fMRI scanning while reading scenarios pertaining either to social emotions, which require the representation of another person’s mental states, or to basic emotions, which do not. Pubertal stage and menarcheal status were used to assign girls to early or late puberty groups. Across the entire sample, the contrast between social versus basic emotion resulted in activity within the social brain network, including dorsomedial prefrontal cortex (DMPFC), the posterior superior temporal sulcus, and the anterior temporal cortex (ATC) in both hemispheres. Increased hormone levels (independent of age) were associated with higher left ATC activity during social emotion processing. More advanced age (independent of hormone levels) was associated with lower DMPFC activity during social emotion processing. Our results suggest functionally dissociable effects of pubertal hormones and age on the adolescent social brain.  相似文献   
119.
Frequently studies of learning and memory measure a single focal behaviour; however it is likely that any learning paradigm will alter multiple behavioural traits in the same animal. We used video footage of the great pond snail (Lymnaea stagnalis), collected immediately prior to both training and testing for memory in response to operant conditioning to reduce aerial respiration, to measure two additional alternate behavioural traits: reducing the size of the pneumostome (breathing orifice) opening and shell tilt to cover the pneumostome. Typically, the training regime used here results in memory to reduce the number of breathing attempts lasting 24?h but not 72?h. However, memory duration when measured using the two additional behavioural traits differed significantly; shell tilt was short-lived lasting less than 1?h following training, whereas the reduction in pneumostome size was still apparent 72?h following training. Therefore, conclusions about the ability of L. stagnalis to retain memory in response to a single type of training regime will differ significantly depending on the focal behavioural trait measured. A significant correlation between the reduction in opening attempts and visible pneumostome area indicated that these behavioural traits are co-specialised, whereas pneumostome opening and shell tilt behaviour varied independently.  相似文献   
120.
Over the past decade, increasing attention has been paid to gender‐related consumption behaviour. However, a relative gap in our knowledge still exists when it comes to understanding the changes that occur as a result of motherhood and how this may influence their interactions in the retail environment. The purpose of this article is to explore stay‐at‐home mothers’ experiences in the servicescape to gain a better understanding of how they associate with servicescapes during this transitional period, how they use retail space to suit their needs, and how they use retail space to negotiate their role as a stay‐at‐home mother. Five stay‐at‐home mothers with children younger than 5 years were provided with disposable cameras and asked to photograph servicescapes that they visited regularly. Over a 1‐year period, they were interviewed several times, and photo‐elicitation techniques were used throughout the interviewing process. The results of this study suggest that when consumers undergo role or identity changes, certain places can be used to smooth this process. Not only can the retail environment be used as a coping mechanism for stay‐at‐home mothers, it can also be viewed as a “second place” as opposed to a “third place”, thus enabling isolated consumers to feel connected with the outside world. Last, this study highlights the temporal dimensions of place. Throughout one's lifetime, one will form attachments to and patronise different places, which will evolve and change as individuals, accordingly, take on different roles and identities. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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