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981.
In rodents, fear conditioned responses are more pronounced toward olfactory stimulus, since olfaction is a dominant sense in these subjects. The present study was outlined to investigate if the association between coffee odor (CS1) and electrical footshock (US) would be an effective model for the study of fear-induced behavior and whether compounds used in humans for emotional-related disorders such as midazolam, propranolol, or scopolamine, applied during the different stages of fear conditioning (acquisition, consolidation and expression), affect the defensive responses to both, the olfactory CS1, and the context (CS2) where the CS1 had been presented (second order conditioning). The results revealed that five pairings between coffee odor (CS1) and electrical footshock (US) were able to elicit consistent defensive responses and a second order conditioning to the context (CS2). Midazolam (0.375–0.5 mg/kg; i.p.) treatment was able to interfere with the CS1–US association and with the consolidation of the aversive information. The propranolol (5–10 mg/kg; i.p.) treatment interfered with the CS1–US association, with the retention of fear memory and with the CS1–CS2 association. Propranolol also attenuated the expression of conditioned fear responses when applied before the CS1 test session. Scopolamine (0.6–1.2 mg/kg; i.p.) treatment impaired the acquisition of CS1–US and CS1–CS2 associations, and also disrupted the expression of conditioned fear responses when injected prior to the CS1 test session. These findings have pointed out the usefulness for the olfactory fear conditioning paradigm to investigate drug effects on the acquisition, consolidation and expression of fear conditioned responses.  相似文献   
982.
Ubiquitous Computing, Pervasive Computing, Physical Computing, Everyware, Tangible User Interface, and the Internet of Things all share the same viewpoint—a viewpoint that sees computers, phones, and game consoles as no longer being the only devices in our environment deemed worthy to embody computation and be connected. Each of these approaches focuses on slightly different aspects of the features and potentialities of the enabling technologies (i.e., Physical Computing focuses on the growing power of microcontrollers; IOT on the increasing influence of tagging systems; Everyware on the pervasiveness of the web through wired and wireless connections, etc.) We understand and place more emphasis on the similarities then the differences among these approaches, and at the same time, we try to address specific human activity issues by exploiting these new enabling technologies and visions. In the paper, we present a project, Wi-roni, that addresses two issues: in-person communication and the added value of being in a given location when accessing a given content. To this end, we considered in some detail the possibilities of three of these enabling technologies: ultrasound sensors, MEMS, and mash-up of Internet application. These technologies were chosen based on the nature of the human activity, and not vice versa. In Wi-roni, an Urban Architecture project located in the La Gora public park in Monteroni d'Arbia, a small village in the province of Siena (Italy), we developed two interconnect solutions: Wi-wave, a column for accessing web audio content in public spaces, and Wi-swing, a children’s swing that tells stories while swinging. These devices represent both the concrete grounds from which to begin to address the abovementioned human activity issues and the playground in which to explore the new, emerging interaction modalities that the enabling technologies could allow.  相似文献   
983.
We conducted preference assessments with 4 typically developing children to identify potential reinforcers and assessed the reinforcing efficacy of those stimuli. Next, we tested two predictions of economic theory: that overall consumption (reinforcers obtained) would decrease as the unit price (response requirement per reinforcer) increased and that the cost and benefit components that defined unit price would not influence overall consumption considerably when unit price values were equal. We tested these predictions by arranging unit price such that the denominator was one (e.g., two responses produced one reinforcer) or two (e.g., four responses produced two reinforcers). Results showed that consumption decreased as unit price increased and that unit price values with different components produced similar consumption.  相似文献   
984.
We examined the possibility that assessment regulatory mode orientation affects the tendency to exhibit transference effects in social perception. Based on a social cognitive methodological paradigm devised by Andersen and colleagues [e.g., Andersen, Glassman, Chen, & Cole, 1996], we find that the transference effect is more pronounced when individuals’ (chronic) assessment orientation is low (vs. high). These results suggest that transference is more likely to occur when less attention is directed towards the target of perception.  相似文献   
985.
Researchers hypothesize that a state of limited cognitive processing capacity increases aggression. In the context of the triggered displaced aggression (TDA) paradigm, a 2 (Salience of triggering event: high/low) × 2 (Cognitive load at trigger: yes/no) × 2 (Cognitive load at aggression: yes/no) between participants experiment tested this hypothesis. Results showed that inducing cognitive load in previously provoked participants while they received a triggering provocation augmented aggression toward the target when the latter was highly salient. Affective reactions to the trigger partially mediated this effect. In contrast to expectation, however, inducing cognitive load while participants aggressed against their target did not affect aggression levels. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
986.
Brain-derived neurotrophic factor (BDNF) plays a regulatory role in neuronal differentiation and synaptic plasticity and has been linked to glucose regulation and cognition. Associations among plasma BDNF, cognition, and insulin function were explored. Forty-one participants with impaired insulin function (IIF), ranging from insulin resistance to type 2 diabetes mellitus (T2DM), were matched with 41 healthy controls on gender, age, education, and IQ. Participants received complete medical, neurological, psychiatric, and neuropsychological evaluations. IIF individuals had significantly lower plasma BDNF levels than controls, particularly females, and higher BDNF levels were associated with poorer explicit memory in IIF females, suggesting that higher levels within this group may reflect the body’s efforts to respond to damage. After accounting for age, education, and HbA1c, BDNF significantly predicted 13.1–23.5% of the variance in explicit memory in IIF women. These findings suggest that BDNF elevations within diseased groups may not always be a marker of health.  相似文献   
987.
Extraversion and Neuroticism are two fundamental dimensions of human personality that influence cognitive functioning in healthy subjects. Little is known about personality changes that may occur in patients with multiple sclerosis (MS) nor about, in particular, their neurofunctional basis. The aim of this study is to determine the impact of personality characteristics on brain activity in patients with MS. Eighteen patients with clinically definite relapsing-remitting MS without any evidence of psychiatric or cognitive disorders and thirteen healthy controls matched for age, gender and education were investigated using functional magnetic resonance imaging (fMRI) during the execution of an “n-back” task. No differences were detected on the behavioral tests between the two groups, although the MS patients had lower total IQ and showed a trend towards higher Extraversion and Neuroticism scores than did the controls. fMRI analyses demonstrated that Extraversion scores were positively associated with brain activity in the fronto-parietal network including the superior parietal lobule and dorsolateral prefrontal cortex in both groups during the high load condition of the n-back task. Given the overlapping neural systems found in the two groups, we suggest that the neural activity associated with specific personality dimension is a neurophysiological characteristic preserved in patients with MS at an early stage in the course of their disease.  相似文献   
988.
For over four decades the Wisconsin Card Sorting Test (WCST) has been one of the most distinctive tests of prefrontal function. Clinical research and recent brain imaging have brought into question the validity and specificity of this test as a marker of frontal dysfunction. Clinical studies with neurological patients have confirmed that, in its traditional form, the WCST fails to discriminate between frontal and non-frontal lesions. In addition, functional brain imaging studies show rapid and widespread activation across frontal and non-frontal brain regions during WCST performance. These studies suggest that the concept of an anatomically pure test of prefrontal function is not only empirically unattainable, but also theoretically inaccurate. The aim of the present review is to examine the causes of these criticisms and to resolve them by incorporating new methodological and conceptual advances in order to improve the construct validity of WCST scores and their relationship to prefrontal executive functions. We conclude that these objectives can be achieved by drawing on theory-guided experimental design, and on precise spatial and temporal sampling of brain activity, and then exemplify this using an integrative model of prefrontal function [i.e., Miller, E. K. (2000). The prefrontal cortex and cognitive control. Nature Reviews Neuroscience, 1, 59–65.] combined with the formal information theoretical approach to cognitive control [Koechlin, E., & Summerfield, C. (2007). An information theoretical approach to prefrontal executive function. Trends in Cognitive Sciences, 11, 229–235.].  相似文献   
989.
Within mainstream social psychology, consumer behavior has been explained mainly in terms of the theory of planned behavior (TPB). Recently, some authors suggested that self‐identity dimensions can explain different types of intentions. To compare the predictive power of a tentative new model of self‐expressive consumer behavior with that of the TPB, three studies were conducted in which, besides the classical variables of the model of TPB, variables concerning self‐identity were also taken into account. Three independent samples (N1= 257, N2= 214, N3= 298) were recruited to study the intention to buy fashionable watches, trendy backpacks, and cellular telephones in relation to the aforementioned variables derived from TPB and from identity theory. Data analyses, based on structural equation modeling, show that identity variables contribute significantly to the explanation of purchase intention.  相似文献   
990.
The effects of benzodiazepines on various types of aggression have been extensively studied. These substances produce their pharmacological effects by allosterically modulating the action of GABA via specific recognition sites on the GABAA receptor called omega 1 and omega 2. The antiaggressive profile of non‐benzodiazepine compounds that also act at omega sites, such as zopiclone (a non‐selective omega 1 and 2 ligand) and zolpidem (a selective omega 1 ligand) has been scarcely explored. In this study, we examined the action of zolpidem (0.75‐3 mg/kg, intraperitoneally) and zopiclone (1.5‐6 mg/kg), administered acutely or subchronically for 10 days, on agonistic behavior elicited by isolation in male mice. Individually housed mice were exposed to anosmic “standard opponents” 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. Acute treatment with zopiclone produced a marked antiaggressive effect, reducing offensive behaviors (threat and attack) at all doses used (1.5, 3, and 6 mg/kg) without affecting immobility. Likewise, the intermediate dose of zolpidem (1.5 mg/kg) significantly decreased aggression in a specific manner, without altering immobility, whereas the highest dose (3 mg/kg) provoked a reduction of aggression accompanied by a weak (but significant) increase of immobility. With repeated treatment, no tolerance to the antiaggressive effects of zopiclone and zolpidem was developed. It is concluded that omega sites at the GABAA receptor could be involved in the control of aggression. Aggr. Behav. 28:416–425, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
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