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861.
The present study examines long-term correlated change in personality traits in old age across a time period of 12 years. Data from the Interdisciplinary Study on Adult Development were used to investigate different aspects of personality change and stability. The sample consisted of 300 adults ranging from 60 to 64 years of age at Time 1. Personality was measured with the NEO Five-Factor Inventory. Longitudinal structural stability, differential stability, change in interindividual differences, mean-level change, and correlated change of the 5 personality traits were examined utilizing structural equation modeling. After having established strict measurement invariance, factor variances in Openness to Experience and Conscientiousness were found to be different across testing occasions, implying variant covariation patterns over time. Stability coefficients were around .70, indicating high but not perfect differential stability. The amount of interindividual differences increased with respect to Openness to Experience and Conscientiousness. Both mean-level change and stability in personality were observed. Eventually, except for Neuroticism, a number of medium effect-sized correlations among changes in personality traits emerged, implying that personality changes share a substantial amount of commonality.  相似文献   
862.
Recent large-scale longitudinal aging studies question earlier claims that higher education protects against cognitive decline in older age. In the present study, the authors addressed this issue by determining whether educational level had an attenuating effect on the rate of cognitive change assessed with a broad range of neuropsychological tests in a community sample of 872 healthy individuals aged 49 to 81 years at baseline. The participants were followed for 6 years and were tested 3 times (at baseline and at 3 and 6 years after baseline). Results of linear mixed-model analyses showed that education had no significant effect on cognitive change over time. These results are discussed in terms of the age range of the sample, definition and range of education, cognitive measures used, length of the study and number of consecutive assessments, and confounding effect of health. The findings question the extent of the presumed protective effects of higher education on cognitive decline during normal aging.  相似文献   
863.
We investigated the development of code specific representations of different kinds of information in long term memory. Forty second graders, 40 sixth graders and 40 adults learned the associations between 12 pictures and one position each in a 4 × 3 grid of squares, 12 pictures and 1 of 12 monosyllabic words each or 12 pictures and 1 of 12 faces. After a 3 min distractor task, a picture was presented in the retrieval phase, and the associated position, word or face had to be selected. Performance in the verbal condition improved as a function of age, while performance in the spatial condition turned out to be independent of age, and the performance in the facial condition showed a difference between both child groups and the adults. The results revealed a developmental difference of code specific representation of different kinds of information.  相似文献   
864.
In this study, the authors examined the Substance Abuse Subtle Screening Inventory‐3 Correctional scale's sensitivity and specificity at detecting college students' illegal behaviors. Sensitivity was strong, but specificity was weak. Implications for counseling and suggestions for future research are included.  相似文献   
865.
Psychosocial factors have been shown to play an important role in the aetiology of coronary heart disease (CHD). A strong association between CHD and socioeconomic status (lower-level education, poor financial situation) has also been well established. Socioeconomic differences may thus also have an effect on psychosocial risk factors associated with CHD, and socioeconomic disadvantage may negatively affect the later prognosis and quality of life of cardiac patients. The aim of this study was to review the available evidence on socioeconomic differences in psychosocial factors which specifically contribute to CHD. A computer-aided search of the Medline and PsycINFO databases resulted in 301 articles in English published between 1994 and 2007. A comprehensive screening process identified 12 empirical studies which described the socioeconomic differences in CHD risk factors. A review of these studies showed that socioeconomic status (educational grade, occupation or income) was adversely associated with psychosocial factors linked to CHD. This association was evident in the case of hostility and depression. Available studies also showed a similar trend with respect to social support, perception of health and lack of optimism. Less consistent were the results related to anger and perceived stress levels. Socioeconomic disadvantage seems to be an important element influencing the psychosocial factors related to CHD, thus, a more comprehensive clarification of associations between these factors might be useful. More studies are needed, focused not only on well-known risk factors such as depression and hostility, but also on some lesser known psychosocial factors such as Type D and vital exhaustion and their role in CHD.  相似文献   
866.
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   
867.
Sellbom M  Bagby RM 《Assessment》2008,15(2):165-176
Schinka, Kinder, and Kremer developed "validity" scales for the Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae) to detect underreporting-the Positive Presentation Management (PPM) Scale and overreporting-the Negative Presentation Management (NPM) Scale. In this investigation, the clinical utility of these scales was examined using the established validity scales from the Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher et al.) as the referent. The sample was composed of 370 psychiatric patients who completed the NEO PI-R and the MMPI-2 as part of a routine evaluation. Results indicated that response distortion compromised the utility of the NEO PI-R domain scales. Moreover, the PPM and NPM scales and an NPM-PPM index significantly differentiated invalid under-and overreporting groups from a valid responding group. The PPM and NPM-PPM index were adequate in classifying under- and overreporters, respectively.  相似文献   
868.
Methylphenidate treatment is used for Attention Deficit Hyperactivity Disorder and can improve learning and memory. Previously, improvements were considered a by-product of increased attention; however, we hypothesize that methylphenidate directly alters mechanisms underlying learning and memory, and therefore examined its effects on hippocampal long-term potentiation and long-term depression. Methylphenidate enhanced both mechanisms in the absence of presynaptic changes and in a noradrenalin beta-receptor-dependent manner. These findings can explain both the improved learning and memory and decreased learning selectivity found with methylphenidate treatment and constitute the first demonstration of direct actions of methylphenidate on mechanisms implicated in cognition.  相似文献   
869.
Research of the Gujarati Hindu communities of the United Kingdom and New Zealand has uncovered an extraordinary diversity of belief concerning the miraculous consumption of devotional food offerings by murtis. Devotees of certain traditions have experienced these events first-hand, but many Hindus believe the process is more subtle. Others suggest that such claims are attempts to gain spiritual authority among Hindus in the diaspora, some dismiss them as simply fraudulent. This article examines the appetite of the divine and how it is understood and contested by various Gujarati Hindu traditions in the United Kingdom and in New Zealand. It will assess the significance of food miracles and how they strengthen ideas of religious identity and spiritual validity as well as their role creating a palpable tension between traditions as to who authoritatively represents Hinduism in the diaspora.  相似文献   
870.
Decision making, impulsivity and time perception   总被引:4,自引:0,他引:4  
Time is an important dimension when individuals make decisions. Specifically, the time until a beneficial outcome can be received is viewed as a cost and is weighed against the benefits of the outcome. We propose that impulsive individuals experience time differently, that is with a higher cost. Impulsive subjects, therefore, overestimate the duration of time intervals and, as a consequence, discount the value of delayed rewards more strongly than do self-controlled individuals. The literature on time perception and impulsivity, however, is not clear cut and needs a better theoretical foundation. Here, we develop the theoretical background on concepts of time perception, which could lead to an empirically based notion of the association between an altered sense of time and impulsivity.  相似文献   
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