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31.
We conducted this cross-sectional study among 392 Japanese and 294 Vietnamese mothers who attended routine child health visits in a Japanese city and at a tertiary hospital in Vietnam, in order to investigate the prevalence and associated sociodemographic, parenting, and psychological characteristics of low maternal confidence in child rearing among them. All data were collected from medical files in Japan, and from medical files and self-administered questionnaires in Vietnam. The proportion of mothers without secure feeling of confidence in the present study was 22% in Japan and 66% in Vietnam. Significant factors associated with a lack of confidence were first-time motherhood and unintended pregnancy in the Japanese dataset and younger age in the Vietnamese dataset. In both groups, a higher proportion of mothers who lacked confidence reported negative parenting outcomes than did confident mothers. Among the three psychological measurements (mood, self-efficacy and depression), higher self-efficacy was associated independently with a significantly reduced risk of not having confidence in child rearing. These results suggest the importance of developing parenting support programs to help Japanese and Vietnamese mothers, particularly those who are young, first-time mothers or who became pregnant unexpectedly, improve their self-efficacy.  相似文献   
32.
Two studies of ethnically diverse US college students from northern California examined whether ingroup bias and gender norm violations influence acquaintance rape attributions (Study 1, N?=?118; Study 2, N?=?140). Participants read vignettes depicting acquaintance rape and completed questionnaires. Victims were part of participants’ ingroup or outgroup. Study 1 manipulated the victim’s sexual history (chaste or promiscuous). Study 2 manipulated the victim’s alcohol use (sober or intoxicated). Ingroup victims were perceived more positively than outgroup victims if the victims were promiscuous or intoxicated. More guilt was attributed to rapists of ingroup victims than outgroup victims if the victims were promiscuous or intoxicated. Findings are examined in relation to ingroup bias and gender norm violations.  相似文献   
33.
Activation of β-adrenergic receptors (β-ARs) enhances hippocampal memory consolidation and long-term potentiation (LTP), a likely mechanism for memory storage. One signaling pathway linked to β-AR activation is the cAMP-PKA pathway. PKA is critical for the consolidation of hippocampal long-term memory and for the expression of some forms of long-lasting hippocampal LTP. How does β-AR activation affect the PKA-dependence, and persistence, of LTP elicited by distinct stimulation frequencies? Here, we use in vitro electrophysiology to show that patterns of stimulation determine the temporal phase of LTP affected by β-AR activation. In addition, only specific patterns of stimulation recruit PKA-dependent LTP following β-AR activation. Impairments of PKA-dependent LTP maintenance generated by pharmacologic or genetic deficiency of PKA activity are also abolished by concurrent activation of β-ARs. Taken together, our data show that, depending on patterns of synaptic stimulation, activation of β-ARs can gate the PKA-dependence and persistence of synaptic plasticity. We suggest that this may allow neuromodulatory receptors to fine-tune neural information processing to meet the demands imposed by numerous synaptic activity profiles. This is a form of “metaplasticity” that could control the efficacy of consolidation of hippocampal long-term memories.The hippocampus importantly contributes to memory function in the mammalian brain (Zola-Morgan et al. 1986; Eichenbaum et al. 1990; Otto and Eichenbaum 1992; Phillips and LeDoux 1992; Remondes and Schuman 2004). It has reciprocal connections with numerous cortical areas, including those responsible for high-level integration of spatial and contextual data from the external environment (Lavenex and Amaral 2000). As such, the hippocampus is well positioned to receive and survey a broad range of information and select behaviorally salient data for long-term storage. Activity-dependent enhancement of hippocampal synaptic strength can store information carried in patterns of afferent neural activity (Bliss and Collingridge 1993; Moser et al. 1998; Nathe and Frank 2003; Whitlock et al. 2006). Substantial evidence suggests that long-term potentiation (LTP) of synaptic strength plays important roles in the formation of long-term memory (LTM) (Doyere and Laroche 1992; Bourtchuladze et al. 1994; Abel and Lattal 2001; Genoux et al. 2002). As such, mechanistic studies of LTP have shed valuable light on how the mammalian brain stores new information.The hippocampus receives dense noradrenergic projections from the locus coeruleus, a brain structure that can influence many vital brain functions, including attention, sleep, arousal, mood regulation, learning, and memory (Berridge and Waterhouse 2003). Both α- and β-adrenergic receptor subtypes are present on hippocampal neurons (Morrison and Foote 1986; Berridge and Waterhouse 2003), and noradrenaline (NA) acts on hippocampal β-adrenergic receptors (β-ARs) to facilitate the retention and recall of memory (Izquierdo et al. 1998; Ji et al. 2003; Murchison et al. 2004). In humans, stimulation of the noradrenergic neuromodulatory system enhances memory for emotional stimuli, and inhibition of β-ARs prevents this memory enhancement (Cahill et al. 1994; van Stegeren et al. 1998; O’Carroll et al. 1999).Consistent with the notion that selective enhancement of LTM may occur following β-AR activation, stimulation of β-ARs can also facilitate the persistence of LTP. In areas CA3 and CA1, β-AR activation facilitates the induction of long-lasting LTP when paired with certain patterns of electrical stimulation (Huang and Kandel 1996; Gelinas and Nguyen 2005). However, the mechanisms by which different patterns of stimulation control synaptic responsiveness to β-AR activation are unclear.β-ARs couple to guanine-nucleotide-binding regulatory Gs proteins to stimulate adenylyl cyclase activity and increase intracellular cAMP (Seeds and Gilman 1971; Maguire et al. 1977). A main target of cAMP signaling is activation of cAMP-dependent protein kinase (PKA), a kinase that is required for some forms of long-lasting LTP and for consolidation of hippocampal LTM (Frey et al. 1993; Abel et al. 1997; Nguyen and Woo 2003). Interestingly, the PKA-dependence of hippocampal LTP displays plasticity: Specific temporal patterns of synaptic stimulation, such as repeated and temporally spaced 100-Hz stimulation, elicit LTP that requires PKA for its expression (Woo et al. 2003). Also, spatial “enrichment” can increase the PKA-dependence of LTP in mice, and this is correlated with improved hippocampal memory function (Duffy et al. 2001). However, it is unclear whether activation of β-ARs can critically gate the PKA-dependence of LTP. In this study, we examine the effects of β-AR activation on LTP generated by various patterns of afferent stimulation in area CA1 of the hippocampus, and we determine the role of PKA in these β-AR-modulated forms of LTP.  相似文献   
34.
We give complete sequent-like tableau systems for the modal logics KB, KDB, K5, and KD5. Analytic cut rules are used to obtain the completeness. Our systems have the analytic superformula property and can thus give a decision procedure. Using the systems, we prove the Craig interpolation lemma for the mentioned logics.  相似文献   
35.
36.
Classical conditioning of the rabbit nictitating membrane (NM) response was adapted as a model system for simultaneous measurement of behavioral and neural responses in auditory signal detection. Animals were trained to a 36-dB spectral-level white-noise CS paired with a corneal airpuff US. The CS intensity was then reduced to threshold, using a modified staircase procedure, and responses on detect and nondetect trials were compared for the same stimulus intensities. At threshold, the behavioral NM response was dichotomous, being present on detect trials and completely absent on nondetect trials. In marked contrast, evoked neural unit activity to the CS recorded from the anteroventral cochlear nucleus was clearly present and identical on both detect and nondetect trials, suggesting that the detection “decision” is made more centrally than the cochlear nucleus.  相似文献   
37.
Many studies have used "reverse" genetics to produce "knock-out" and transgenic mice to explore the roles of various molecules in long-term potentiation (LTP) and spatial memory. The existence of a variety of inbred strains of mice provides an additional way of exploring the genetic bases of learning and memory. We examined behavioral memory and LTP expression in area CA1 of hippocampal slices prepared from four different inbred strains of mice: C57BL/6J, CBA/J, DBA/2J, and 129/SvEms-+(Ter?)/J. We found that LTP induced by four 100-Hz trains of stimulation was robust and long-lasting in C57BL/6J and DBA/2J mice but decayed in CBA/J and 129/SvEms-+(Ter?)/J mice. LTP induced by one 100-Hz train was significantly smaller after 1 hr in the 129/SvEms-+(Ter?)/J mice than in the other three strains. Theta-burst LTP was shorter lasting in CBA/J, DBA/2J, and 129/SvEms-+(Ter?)/J mice than in C57BL/6J mice. We also observed specific memory deficits, among particular mouse strains, in spatial and nonspatial tests of hippocampus-dependent memory. CBA/J mice showed defective learning in the Morris water maze, and both DBA/2J and CBA/J strains displayed deficient long-term memory in contextual and cued fear conditioning tests. Our findings provide strong support for a genetic basis for some forms of synaptic plasticity that are linked to behavioral long-term memory and suggest that genetic background can influence the electrophysiological and behavioral phenotypes observed in genetically modified mice generated for elucidating the molecular bases of learning, memory, and LTP.  相似文献   
38.
Developmental psychologists have describedimitation as a process that suggests perspective-taking abilities. However, imitative behavior has been found in animals, which are generally not considered capable of taking the perspective of another. Previous studies with birds have demonstrated the imitation of a single response (sometimes referred to asaction-level imitation). In the present experiment, we examined the extent to which pigeons would imitate an unfamiliar sequence of two behaviors (sometimes referred to asprogram-level imitation). Our results indicate that, although there are individual differences, pigeons show a significant tendency to match a demonstrated sequence of behavior involving, first, a response to a treadle (pecking at it or stepping on it) and, second, pushing aside a screen that blocks access to food (a left-vs.-right push).  相似文献   
39.
Discourse about discourse or a subject's comments about his/her performance during a discourse task can be defined as modalizing discourse (discours modalisateur; [Nespoulous, 1980]; [Nespoulous et al., 1998]). Since it does not convey the expected content of the discourse task (referential discourse), modalizing discourse has often been considered non-informative, and as such, has received little interest. The present study investigated the modalizing aspect of discourse production and its evolution in Alzheimer's disease (AD). Five AD patients produced a picture-induced narrative across five consecutive assessments. Two measures were derived: the modalizing/referential ratio (M/R ratio) and the percentage of repeated ideas. Results revealed that, compared to a group of 27 normal controls matched for age and education, AD patients: (1) obtained higher M/R ratios that tended to diminish as the number of assessments increased, and (2) produced higher percentages of repeated ideas throughout all assessments. These results suggest that modalizing discourse makes up a large proportion of AD patients' discourse and should be included in further studies to accurately describe their discourse behavior. The implications of modalizing discourse on preserved pragmatic abilities and its inclusion in comprehensive management programs of AD patients are discussed.  相似文献   
40.
Responses of 289 university students to Belicki's Nightmare Distress Questionnaire and the Stress-related Health Problems Scale were used to test the hypothesis that persons who score high on nightmare distress are more likely to report psychological problems. Since relative to the Low Nightmare Distress group, the High Nightmare Distress group scored significantly higher on all seven of the sets of symptoms that are measured by the Stress-related Health Problems Scale, this hypothesis was supported.  相似文献   
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