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961.
The effect of task difficulty on inter-task transfer is a classic issue in motor learning. We examined the relation between self-efficacy and transfer of learning after practicing different versions of a stick balancing task. Practicing the same task or an easier version led to significant pre- to post-test transfer of learning, whereas practicing a more difficult version did not. Self-efficacy increased modestly from pre- to post-test with easy practice, but decreased significantly with difficult practice. In addition, self-efficacy immediately prior to the post-test was significantly lower after difficult practice than easy or intermediate practice. Self-efficacy immediately prior to the post-test, performance at the end of practice, and pre-test performance explained 75% of the variance in post-test performance. The mediating role of self-efficacy on transfer of learning offers an alternative explanation for recent findings on the superiority of easy-to-difficult transfer and may help clarify inconsistencies in earlier research.  相似文献   
962.
Kv4.2 channels contribute to the transient, outward K(+) current (A-type current) in hippocampal dendrites, and modulation of this current substantially alters dendritic excitability. Using Kv4.2 knockout (KO) mice, we examined the role of Kv4.2 in hippocampal-dependent learning and memory. We found that Kv4.2 KO mice showed a deficit in the learning phase of the Morris water maze (MWM) and significant impairment in the probe trial compared with wild type (WT). Kv4.2 KO mice also demonstrated a specific deficit in contextual learning in the fear-conditioning test, without impairment in the conditioned stimulus or new context condition. Kv4.2 KO mice had normal activity, anxiety levels, and prepulse inhibition compared with WT mice. A compensatory increase in tonic inhibition has been previously described in hippocampal slice recordings from Kv4.2 KO mice. In an attempt to decipher whether increased tonic inhibition contributed to the learning and memory deficits in Kv4.2 KO mice, we administered picrotoxin to block GABA(A) receptors (GABA(A)R), and thereby tonic inhibition. This manipulation had no effect on behavior in the WT or KO mice. Furthermore, total protein levels of the α5 or δ GABA(A)R subunits, which contribute to tonic inhibition, were unchanged in hippocampus. Overall, our findings add to the growing body of evidence, suggesting an important role for Kv4.2 channels in hippocampal-dependent learning and memory.  相似文献   
963.
Although self-report measures of dispositional mindfulness have good psychometric properties, a few studies have shown unexpected positive correlations between substance use and mindfulness scales measuring observation of present-moment experience. The current study tested the hypothesis that the relationship between present-moment observation and substance use is moderated by the tendency to be nonjudgmental and nonreactive toward the observed stimuli. Two hundred and ninety-six undergraduates completed the five-facet mindfulness questionnaire (FFMQ), a calendar measuring periods of substance use, and a measure of the five-factor model of personality. Controlling for FFMQ and personality subscales, significant interactions between the observing and nonreactivity subscales indicated that the observing subscale was negatively associated with substance use at higher levels of nonreactivity but positively associated with periods of substance use at lower levels of nonreactivity. Results support the use of statistical interactions among FFMQ subscales to test for the presence of interactive effects of different aspects of mindfulness.  相似文献   
964.
Researchers have argued that the investigation of causal interrelationships between symptoms may help explain the high comorbidity rate between certain psychiatric disorders. Clients' own attributions concerning the causal interrelationships linking the co-occurrence of their symptoms represent data that may inform their clinical case conceptualization, treatment, and psychological theory regarding the etiology of comorbid disorders. The present study developed and evaluated a novel psychological assessment methodology for measuring Perceived Causal Relations (PCR) and examined its psychometric properties as applied to the question of whether posttraumatic stress and anxiety symptoms represent causal risk factors for depressive symptoms in 225 undergraduates. Participants attributed their symptoms of anxiety and posttraumatic reexperiencing as significant causes of their depressive symptoms. Exploratory analyses identified a listing of symptoms reliably attributed as significant causes of other symptoms and functional impairment, as well as a listing of symptoms reliably attributed as significant effects (outcomes) of other symptoms and functional impairment. The PCR method has promise as an idiographic approach to assessing the causes and consequences of comorbid psychiatric symptoms and associated functional impairment. Research is required to assess the relevance and replicate these findings in distinct psychiatric groups experiencing various symptomatic presentations. Future research may also examine PCR ratings associating other individual differences, for example, between measures of history (e.g., life events), life choices, and personality.  相似文献   
965.
Epigenetic regulation of chromatin structure is an essential molecular mechanism that contributes to the formation of synaptic plasticity and long-term memory (LTM). An important regulatory process of chromatin structure is acetylation and deacetylation of histone proteins. Inhibition of histone deacetylase (HDAC) increases acetylation of histone proteins and facilitate learning and memory. Nitric oxide (NO) signaling pathway has a role in synaptic plasticity, LTM and regulation of histone acetylation. We have previously shown that NO signaling pathway is required for contextual fear conditioning. The present study investigated the effects of systemic administration of the HDAC inhibitor sodium butyrate (NaB) on fear conditioning in neuronal nitric oxide synthase (nNOS) knockout (KO) and wild type (WT) mice. The effect of single administration of NaB on total H3 and H4 histone acetylation in hippocampus and amygdala was also investigated. A single administration of NaB prior to fear conditioning (a) rescued contextual fear conditioning of nNOS KO mice and (b) had long-term (weeks) facilitatory effect on the extinction of cued fear memory of WT mice. The facilitatory effect of NaB on extinction of cued fear memory of WT mice was confirmed in a study whereupon NaB was administered during extinction. Results suggest that (a) the rescue of contextual fear conditioning in nNOS KO mice is associated with NaB-induced increase in H3 histone acetylation and (b) the accelerated extinction of cued fear memory in WT mice is associated with NaB-induced increase in H4 histone acetylation. Hence, a single administration of HDAC inhibitor may rescue NO-dependent cognitive deficits and afford a long-term accelerating effect on extinction of fear memory of WT mice.  相似文献   
966.
Psychopaths commit a disproportionate amount of violent crime, and this places a substantial economic and emotional burden on society. Elucidation of the neural correlates of psychopathy may lead to improved management and treatment of the condition. Although some methodological issues remain, the neuroimaging literature is generally converging on a set of brain regions and circuits that are consistently implicated in the condition: the orbitofrontal cortex, amygdala, and the anterior and posterior cingulate and adjacent (para)limbic structures. We discuss these findings in the context of extant theories of psychopathy and highlight the potential legal and policy implications of this body of work.  相似文献   
967.
The affective biasing of attention is not typically considered to be a form of emotion regulation. In this article, we argue that 'affect-biased attention' - the predisposition to attend to certain categories of affectively salient stimuli over others - provides an important component of emotion regulation. Affect-biased attention regulates subsequent emotional responses by tuning one's filters for initial attention and subsequent processing. By reviewing parallel research in the fields of emotion regulation and affect-biased attention, as well as clinical and developmental research on individual differences in attentional biases, we provide convergent evidence that habitual affective filtering processes, tuned and re-tuned over development and situation, modulate emotional responses to the world. Moreover, they do so in a manner that is proactive rather than reactive.  相似文献   
968.
The present study was an examination of how exposure to print affects sentence processing and memory in older readers. A sample of older adults (N = 139; Mean age = 72) completed a battery of cognitive and linguistic tests and read a series of sentences for recall. Word-by-word reading times were recorded and generalized linear mixed effects models were used to estimate components representing attentional allocation to word-level and textbase-level processes. Older adults with higher levels of print exposure showed greater efficiency in word-level processing and in the immediate instantiation of new concepts, but allocated more time to semantic integration at clause boundaries. While lower levels of working memory were associated with smaller wrap-up effects, individuals with higher levels of print exposure showed a reduced effect of working memory on sentence wrap-up. Importantly, print exposure was not only positively associated with sentence memory, but was also found to buffer the effects of working memory on sentence recall. These findings suggest that the increased efficiency of component reading processes that come with life-long habits of literacy buffer the effects of working memory decline on comprehension and contribute to maintaining skilled reading among older adults.  相似文献   
969.
When we behave according to rules and instructions, our brains interpret abstract representations of what to do and transform them into actual behavior. In order to investigate the neural mechanisms behind this process, we devised an fMRI experiment that explicitly isolated rule interpretation from rule encoding and execution. Our results showed that a specific network of regions (including the left rostral prefrontal cortex, the caudate nucleus, and the bilateral posterior parietal cortices) is responsible for translating rules into executable form. An analysis of activation patterns across conditions revealed that the posterior parietal cortices represent a mental template for the task to perform, that the inferior parietal gyrus and the caudate nucleus are responsible for instantiating the template in the proper context, and that the left rostral prefrontal cortex integrates information across complex relationships.  相似文献   
970.
Though people in positions of power have many advantages that sustain their power, stories abound of individuals who fall from their lofty perch. How does this happen? The current research examined the role of illusions of alliance, which we define as overestimating the strength of one’s alliances with others. We tested whether powerholders lose power when they possess overly positive perceptions of their relationships with others, which in turn leads to the weakening of those relationships. Studies 1 and 2 found that powerful individuals were more likely to hold illusions of alliance. Using laboratory as well as field contexts, Studies 3, 4, and 5 found that individuals with power who held illusions of alliance obtained fewer resources, were excluded more frequently from alliances, and lost their power. These findings suggest that power sometimes leads to its own demise because powerful individuals erroneously assume that others feel allied to them.  相似文献   
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