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151.
The positive effect of postlearning sleep on memory consolidation as well as the relationship between sleep-related memory processes and the hippocampal formation are increasingly clarified topics in neurobiology. However, the possibility of a stable relationship between waking mnemonic performance and sleep-dependent hippocampal electric activity is unexplored. Here we report a correlative analysis between sleep-dependent parahippocampal-hippocampal (pHip-Hip) electric activity recorded by foramen ovale (FO) electrodes and different types of memory performances in epileptic patients. Psychological testing was performed days or weeks before electrophysiological recordings. The relative spectral power of the slow activity (below 1.25 Hz) during deep non-REM (NREM) sleep at the right pHip-Hip region correlated positively with the visual memory performance according to Rey-Osterrieth Complex Figure Test (ROCFT). Along the posterior-anterior direction of the hippocampal formation a linear increasing of correlations was observed. The relative power of the activity below 1.25 Hz at the left pHip-Hip during phasic REM sleep correlated positively with verbal learning performance and mnemonic retention values according to ROCFT. It is concluded that the pHip-Hip structures' capacity of producing high amplitude and synchronized slow (< 1 Hz) oscillation during deep NREM sleep is related to the functional power of these structures. We hypothesize that the asymmetric (side-specific) propagation of ponto-geniculo-occipital (PGO) activity to the pHip-Hip region is related to the memory correlates of phasic REM sleep. 相似文献
152.
153.
15名被试在摄人酒精BAL≤0.5‰前后的四个时段内接受一套简单的运算操作任务,近2/3被试的认知一操作能力显示受酒精影响发生变异:酒后30分钟操作时间延滞,至60分钟更具显著性;同时,操作错误亦大幅上升,但变化趋势不同于操作时间。酒精干扰呈现认知“近视”与“远视”的迹象。 相似文献
154.
Two studies are reported which aimed to examine the relationship between phonological sensitivity and the acquisition of new words that systematically differed in the familiarity of their sound structures. In the first study measures of phonological sensitivity, phonological short-term memory, vocabulary, and nonverbal ability were administered to forty-one 5-year-old children. Phonological sensitivity was related to the paired-associate learning of phonologically unfamiliar words, but not to the learning of familiar words. In the second study a group of 14 nonreading 5-year-old children received phonological sensitivity training. A control group was trained in semantic categorization. After the training, the phonological sensitivity group did perform better on measures of letter knowledge and phonological sensitivity (rhyme and first-sound categorization) and appeared to learn phonologically unfamiliar words more easily. The findings of both studies suggest that phonological sensitivity can support the acquisition of novel words. 相似文献
155.
de Azevedo AM 《The Journal of analytical psychology》2000,45(1):75-91
The author first provides her readers with a brief summary of some of Freud's ideas, as found throughout his work, on the notion of 'unconscious'. The notion of unconscious as noun is contrasted to the idea of unconscious as adjective, this latter being proposed as a quality, or a state, ever temporary, dynamic, and subject to the constant changes going on in the individual's internal psychic world, as well as to external conditions. After presenting some considerations, the author then contrasts the Kleinian model of the mind to the Freudian, and Wilfred Bion's contribution is discussed at some length. Within Bion's conception of psychic functioning, the model of 'dream' is highlighted and, in this regard, clarifications are sought regarding Bion's view of the unconscious. To conclude, a brief and superficial approximation to the work of Carl Jung is touched upon, although the author admits to knowing little of Jung's positions. 相似文献
156.
157.
Combinatory logic is known to be related to substructural logics. Algebraic considerations of the latter, in particular, algebraic considerations of two distinct implications (, ), led to the introduction of dual combinators in Dunn & Meyer 1997. Dual combinators are "mirror images" of the usual combinators and as such do not constitute an interesting subject of investigation by themselves. However, when combined with the usual combinators (e.g., in order to recover associativity in a sequent calculus), the whole system exhibits new features. A dual combinatory system with weak equality typically lacks the Church-Rosser property, and in general it is inconsistent. In many subsystems terms "unexpectedly" turn out to be weakly equivalent. The paper is a preliminary attempt to investigate some of these issues, as well as, briefly compare function application in symmetric -calculus (cf. Barbanera & Berardi 1996) and dual combinatory logic. 相似文献
158.
Neuropsychological tests known to reveal abnormalities in patients with frontal lobe damage were used to explore cognitive function in 20 chronic schizophrenic patients. Eleven control subjects, matched on age and NLV-IQ (NLV is the Dutch version of the NART) were also tested. No impairments of planning ability were found on either the Action Program test or the Zoomap test, both subtests from the BADS (Behavioural Assessment of the Dysexecutive Syndrome). No abnormalities were apparent on tests of reactive flexibility, measured by task-switching and by the Rule Shift Cards test, also a subtest of the BADS. Patients with schizophrenia, however, had significantly greater difficulty in inhibiting irrelevant information and in generating words in a verbal fluency task, a measure of spontaneous flexibility. 相似文献
159.
Frontal-Lobe Involvement in Spatial Memory: Evidence from PET,fMRI, and Lesion Studies 总被引:2,自引:0,他引:2
Many studies have identified the prefrontal cortex as the brain area that is critical for spatial memory, both in humans and in other primates. Other studies, however, have failed to establish this relation. Therefore, the aim of this paper was to review the literature regarding the role of the human prefrontal lobe in spatial memory. This was done by examining the evidence obtained from neuropsychological patients and from studies using brain-imaging techniques (PET and fMRI). Evidence supporting the notion that the prefrontal cortex is extensively involved in spatial working memory was found. The majority of these studies, however, suggests that frontal-lobe involvement is not related to the type of material that is being processed (e.g., spatial vs. nonspatial), but to process-specific functions, such as encoding and retrieval. Theoretically, these functions could be linked to the central executive within Baddeley's working-memory model, or to recent theories that emphasize the various processes that play a role in working memory. Also, methodological issues were discussed. Further research is needed to enhance our understanding of the precise interaction of domain-specific and general processes. 相似文献
160.
Because icons, signs, and symbols are now widely used to communicate information, it is essential for system designers to know what makes them easy to use and interpret. The authors report a series of studies that examine characteristics considered central to icon usability. After quantifying the properties of icon concreteness, complexity, and discriminability, the authors assessed each property's effects on user performance when user experience, task demands, and presentation context were systematically varied. Findings indicated that the effects of icon concreteness were primarily associated with the initial grasp of meaning, whereas complexity effects were found to persist longer and to be associated with search efficacy. The effects of icon distinctiveness were complex, but distinctiveness was enhanced by using both semantic and visual contrasts. The implications of these findings for interface design are discussed. 相似文献