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841.
Using a speeded retrieval procedure, we investigated time-of-day effects in automatic and controlled retrieval. Morning-type
adults were tested at either peak (early morning) or off-peak (late afternoon) times on a speeded implicit (Experiment 1)
or explicit (Experiment 2) stem completion task. In Experiment 1, retrieval strategies were identified by changes in response
speed between a practice phase with rapid retrieval and an implicit memory test phase. Performance based on controlled retrieval
(shown by slowdown participants) showed more priming at peak than at off-peak times of day, a finding confirmed in Experiment
2, in which the participants were given intentional retrieval instructions when the materials switched. In contrast, performance
based on automatic retrieval (shown by nonslowdown participants) did not differ across peak and off-peak times. The finding
suggests a robust synchrony effect in controlled retrieval, but not in automatic retrieval, which does not appear to vary
across the day. 相似文献
842.
Leading members of the Slavophile circle shared a commonWeltanschauung, fostered by a complex reaction to thesocial and political changes taking place in mid-nineteenth-centuryRussia. There was, however, considerable diversity in their views aboutthe character and value of the Russian state apparatus. While theyall criticised the bureaucratic ethos of the tsarist state,a number of them recognised that it played a critical role in stabilising deep-seated social tensions in Russian society. Inthe late 1850s, some members of the Slavophile circle also cameto recognise that the state apparatus could play a positiverole in eliminating serfdom. Nevertheless, in the wake ofthe Emancipation Edict of 1861, conflict over the roleof the Russian state became the most divisive issuefor surviving members of the Slavophile circle. 相似文献
843.
Michael Rönnlund Lars Nyberg Lars Bäckman Lars-Göran Nilsson 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(3):182-201
Motor activity during encoding of verbal information has been suggested to reduce age differences in episodic memory. Here we examined memory for sentences encoded with enactment (SPTs, subject-performed tasks) or without enactment (VTs, verbal tasks) in a population-based sample consisting of 10 groups ranging in age from 35 to 80 years (N = 1000). Memory performance was assessed by immediate free- and category-cued recall. Degree of clustering was measured by the adjusted ratio of clustering score. Recall of cognitive activities served as a complementary measure of memory for performed tasks. Sentence recall showed a gradual decline across age, of about the same magnitude for SPTs and VTs, in both free and cued recall. Clustering in free recall was higher for SPTs than for VTs, but there were no age differences in clustering. A pattern of gradual decline from age 35 was observed also in activity recall, regardless of whether the activities involved motor activity or not. Across the memory measures, differences in education accounted for all of the age-related variance in performance among the younger (35-55 years) but not the older groups (60-80 years), suggesting that genuine aging effects in these measures are more prominent in old age. Together, the results indicate that age differences in episodic memory, in line with most, if not all, types of encoding support, generalize across the performed/non-performed distinction. 相似文献
844.
Behavioural flexibility allows animals to adjust their behaviours according to changing environmental demands. Such flexibility is frequently assessed by the discrimination–reversal learning task. We examined grey squirrels’ behavioural flexibility, using a simultaneous colour discrimination–reversal learning task on a touch screen. Squirrels were trained to select their non-preferred colour in the discrimination phase, and their preferred colour was rewarded in a subsequent reversal phase. We used error rates to divide learning in each phase into three stages (perseveration, chance level and ‘learned’) and examined response inhibition and head-switching during each stage. We found consistent behavioural patterns were associated with each learning stage: in the perseveration stage, at the beginning of each training phase, squirrels showed comparable response latencies to correct and incorrect stimuli, along with a low level of head-switching. They quickly overcame perseveration, typically in one to three training blocks. In the chance-level stage, response latencies to both stimuli were low, but during initial discrimination squirrels showed more head-switches than in the previous stage. This suggests that squirrels were learning the current reward contingency by responding rapidly to a stimulus, but with increased attention to both stimuli. In the learned stage, response latencies to the correct stimulus and the number of head-switches were at their highest, whereas incorrect response latencies were at their lowest, and differed significantly from correct response latencies. These results suggest increased response inhibition and attention allowed the squirrels to minimise errors. They also suggest that errors in the ‘learned’ stage were related to impulsive emission of the pre-potent or previously learned responses. 相似文献
845.
Emotion influences memory in many ways. For example, when a mood-dependent processing shift is operative, happy moods promote
global processing and sad moods direct attention to local features of complex visual stimuli. We hypothesized that an emotional
context associated with to-be-learned facial stimuli could preferentially promote global or local processing. At learning,
faces with neutral expressions were paired with a narrative providing either a happy or a sad context. At test, faces were
presented in an upright or inverted orientation, emphasizing configural or analytical processing, respectively. A recognition
advantage was found for upright faces learned in happy contexts relative to those in sad contexts, whereas recognition was
better for inverted faces learned in sad contexts than for those in happy contexts. We thus infer that a positive emotional
context prompted more effective storage of holistic, configural, or global facial information, whereas a negative emotional
context prompted relatively more effective storage of local or feature-based facial information 相似文献
846.
Jerzy Gołosz 《Axiomathes》2018,28(4):395-417
The aim of this paper is to make presentism a dynamic view of reality by basing it on a notion of dynamic existence, that is, on a notion of existence which has a dynamic character. The paper shows that both of the notions of existence which are used in metaphysical theories of time (in presentism and eternalism) have a static character and, while such a notion is useful for eternalists, it is useless for presentists if they want to make their view able to remain in agreement with our everyday experience and self-consistent. It is demonstrated that both empirical and theoretical arguments indicate that the presentist should replace the notion of this static existence with the notion of a dynamic existence and that this maneuver allows the presentist to treat his/her existential thesis as equivalent to the thesis that time flows. Not only does this strategy allow us to express presentism in a simple, homogenous way which remains in agreement with our experience, but also permits us to solve some of the difficult problems which presentism faces, such as, for example, the objection of triviality and the question about the rate of time passage. Moreover, such an approach to presentism allows us to solve fundamental metaphysical problems concerning time such as the problem of the openness of the future and the fixity of the past, direction of causation, and relations between presentism and persistence through time by endurance. 相似文献
847.
848.
849.
850.
David Shaffer Prudence Fisher R. H. Hicks Michael Parides Madelyn Gould 《Suicide & life-threatening behavior》1995,25(Z1):64-71
It has been suggested that there is a strong relationship between suicidal behavior and homosexuality in adolescence. It has been further suggested that it is due to the stigmatization and feelings of isolation that are experienced by many gay adolescents. Much of the literature that has given support to these hypotheses has been conducted on uncontrolled nonrepresentative samples and its generalizability is open to question. An opportunity to examine the relationship in an unselected sample arose in a case control, psychological autopsy study of 120 of 170 consecutive suicides under age 20 and 147 community age, sex, and ethnic matched controls living in the Greater New York City area. Homosexuality was defined as having had homosexual experiences or having declared a homosexual orientation. Three teenagers and no controls met these criteria. The difference was not significant. The circumstances of death were examined and are described. In no instance did suicide directly follow an episode of stigmatization. All three suicides had evidence of significant psychiatric disorder before death. In spite of opportunities for biased reporting, it is concluded that this study finds no evidence that suicide is a common characteristic of gay youth, or that when suicide does occur among gay teenagers, that it is a direct consequence of stigmatization or lack of support. 相似文献