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1.
Compromised retrieval of autobiographical memory (ABM) is well established in neurodegenerative disorders. The recounting of autobiographical events is inextricably linked to linguistic knowledge, yet no study to date has investigated whether tense use during autobiographical narration is disrupted in dementia syndromes. This study investigated the incidence of correct past tense use during ABM narration in patients with Alzheimer's disease (AD,= 10) and semantic dementia (SD, n = 10) in comparison with healthy older Controls (n = 10). Autobiographical narratives were analysed for episodic content (internal/external) and classified according to tense use (past/present). Across both patient groups, use of the past tense was significantly compromised relative to Controls, with increased levels of off‐target present tense verbs observed. Voxel‐based morphometry analyses based on structural MRI revealed differential associations between past tense use and regions of grey matter intensity in the brain. Bilateral temporal cortices were implicated in the SD group, whereas frontal, lateral, and medial temporal regions including the right hippocampus emerged in AD. This preliminary study provides the first demonstration of the disruption of specific linguistic constructs during autobiographical narration in AD and SD. Future studies are warranted to clarify at what point in the disease trajectory such deficits in tense use emerge, and whether these deficits are a product or contributing factor in memory disruption in these syndromes.  相似文献   

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The amygdala is critically involved in discriminative avoidance learning. Large lesions of the amygdala block discriminative avoidance learning and abolish cingulothalamic training-induced neuronal activity. These results indicated that amygdalar processing is critical for cingulothalamic plasticity. The larger lesions did not allow differentiation of the specific functioning of various amygdalar nuclei. Anatomical analysis showed that damage in the central (CE) nucleus of the amygdala was correlated with the severity of the behavioral deficit. The present study was carried out to determine whether smaller lesions, centered in the CE nucleus, would impair discriminative avoidance learning and block cingulothalamic plasticity. In addition, the possible role of the CE nucleus in appetitively motivated discriminative approach learning was examined for the first time. New Zealand White rabbits with CE nuclear lesions were first trained in the discriminative approach task. After attaining asymptotic performance, discriminative avoidance training sessions were alternated with continuing approach training sessions, one session each day. The rabbits with lesions were severely impaired in avoidance learning but showed no impairment of approach learning. Surprisingly, the attenuating effects of the lesions on cingulothalamic training-induced neuronal activity were more prevalent during approach learning than during avoidance learning. These results indicated that avoidance learning can be impaired by lesions centered in the CE nucleus that leave cingulothalamic plasticity largely intact and that the CE nucleus is involved in extra-cingulothalamic learning processes.  相似文献   

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The voice onset time (VOT) of two groups of treated stutterers and a normal-speaking group was assessed by spectrographic analysis. Both groups of stutterers had significantly slower VOT than the normal speakers. The experimental group of stutterers was given 8 wk of “fluency” training designed to remediate characteristics of speech identified as related to “tenuous” fluency. The control group of stutterers received ongoing maintenance therapy. Posttreatment VOT was assessed. The experimental stuttering group had significantly decreased their VOT in the direction of the normal-speaking group, whereas the control group of stutterers had a greater VOT between pre- and posttreatment. The implication of these results for the maintenance of fluency are discussed.  相似文献   

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There is currently an increasing amount of theoretical and empirical work arguing that stereotyped sex role behavior is maladaptive in our culture and that “androgyny” or “sex role transcendence” is a preferred mode of being. The latter, however, seems to require individual inconsistency and self-contradiction in behaviors and attitudes (since the individual is both active and passive, both independent and dependent, etc.). Theories of cognitive consistency maintain that individuals avoid self-contradiction and inconsistency, and therefore that androgyny runs counter to important motivational principles. This article examines this issue in some detail, and concludes that theories of cognitive dissonance and consistency reflect particular socio-cultural conditions rather than universal motivation principles. There is nothing inherently uncomfortable or “inconsistent” about androgyny and sex role transcendence.  相似文献   

6.
Experimentally naive rats can learn rapidly to discriminate among three odors to obtain food reinforcement. After three massed trials, they show almost errorless performance. This task has proved to be useful in studying time-dependent postacquisition intracellular processes necessary for long-term memory. The present experiments evaluated the temporal dynamics of the role of β-noradrenergic receptors in long-term consolidation. Rats were implanted with intracerebroventricular cannulae and trained in a single session to find reinforcement in a hole in a sponge impregnated with a particular odor. Injections of the β-receptor antagonist timolol were made at 5 min, 1, 2, or 5 hr after training. Memory and relearning ability were evaluated 48 hr later. Rats treated with timolol 2 hr after training showed a memory deficit at the retention test, but were able to relearn the task normally. Injections at the earlier or later time points were ineffective. The results reinforce previous observations with systemic injections that β-noradrenergic receptors are involved in the late phase of memory consolidation and suggest a critical time window during which they are necessary. The time window is compatible with the current view that long-term memory depends on late involvement of the cAMP cascade leading to new protein synthesis necessary for synaptic reorganization.  相似文献   

7.
This paper examines the relationship between span memory [e.g., immediate memory, short-term memory (STM), simple span] and general ability (g) though a reanalysis of two data sets [Christal, R. E. (1959). Factor analytic study of visual memory. Psychological Monographs: General and Applied, 72 (13, Whole No. 466); Kelley, H.P. (1964). Memory abilities: A factor analysis. Psychometric Monographs, No. 11]. Because of their large sample sizes and the multiple measures used to identify each construct, the Christal and Kelley studies were examined within a “best evidence synthesis” framework. Modern structural equation modeling (SEM) techniques were used to examine the relationship between immediate memory and g. Results indicated that in both studies, the relationship between immediate memory and g was quite substantial (.71 and .83), and that this relationship was essentially reduced by half when the common content variance of the tests was accounted for (e.g., verbal, spatial, numerical). Results are discussed within the context of recent research examining the relationship between working memory (WM) and g.  相似文献   

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Basal ganglia (BG) lesions cause impairments of different mammalian’s movement and cognition behaviors. Motor circuit impairment has a dominant role in the movement disorders. An inhibitory factor in BG is GABA neurotransmitter, which is released from striatum. Lesions in GABAergic neurons could trigger movement and cognition disorders. Previous evidence showed that GABAB receptor agonist (Baclofen) administration in human improves movement disorders and exercise can improve neurodegenerative and cognitive decline; however, the effects of both Baclofen and mild forced treadmill exercise on movement disorders are not well known. The main objective of this study is to investigate the combined effects of mild forced treadmill exercise and microinjection of Baclofen in the internal Globus Pallidus on striatum lesion-induced impairments of spatial learning and motor activity. We used Morris water maze and open filed tests for studying spatial learning, and motor activity, respectively. Results showed that mild exercise and Baclofen microinjection could not lonely affect the spatial learning, and motor activity impairments while the combination of them could alleviate spatial learning, and motor activity impairments in striatum-lesion animals. Our results suggest that striatum lesion-induced memory and motor activity impairments can improve with combination interaction of GABAB receptor agonist and exercise training.  相似文献   

10.
“Stress” induced by swimming, immobilization, and fighting in male albino mice results in a significant increase of creatine kinase (CK) activity in blood obtained by decapitation. The increase partially depends on motor activity as shown in fighting animals. Males show higher CK values than females. Isolation and even immobilization also lead to higher CK activity, the latter to a similar extent as swimming and fighting. We believe that CK activity is regulated by processes additional to motor activity.  相似文献   

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Oxytocin (OT, 0.10 microg/kg, sc) impaired retention of a one-trial step-through inhibitory avoidance task when injected into male Swiss mice 10 min after training, as indicated by retention performance 48 h later. In contrast, the immediate post-training administration of the putative oxytocin receptor antagonist d(CH(2))(5)[Tyr(Me)(2), Thr(4), Thy-NH(9)(2)] OVT (AOT, 0.30 microg/kg, sc) significantly enhanced retention performance. Neither OT nor AOT affected response latencies in mice not given footshock on the training trial, and neither the impairing effects of OT nor the enhancing effects of AOT were seen when the training-treatment interval was 180 min, suggesting that both treatments influenced memory storage. The effects of OT (0.10 microg/kg, sc) on retention were prevented by AOT (0.03 microg/kg, sc) given immediately after training, but 10 min prior to OT treatment. The central acting anticholinesterase physostigmine (35, 70, or 150 microg/kg, i.p.), but not its quaternary analogue neostigmine (150 microg/kg, i.p.), reversed the impairment of retention performance induced by OT, whereas low subeffective doses of the centrally active muscarinic cholinergic antagonist atropine (0.5 mg/kg, i.p.) or the central acting nicotinic cholinergic antagonist mecamylamine (5 mg/kg, i.p.), but not methylatropine (0.5 mg/kg, i.p.) or hexamethonium (5 mg/kg, i.p.) prevented the enhancement of retention performance caused by AOT. We suggest that oxytocin negatively modulates the activity of central cholinergic mechanisms during the posttraining period that follows an aversively motivated learning experience, leading to an impairment of retention performance of the inhibitory avoidance response.  相似文献   

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Rule‐guided behavior depends on the ability to strategically update and act on content held in working memory. Proactive and reactive control strategies were contrasted across two experiments using an adapted input/output gating paradigm (Neuron, 81, 2014 and 930). Behavioral accuracies of 3‐, 5‐, and 7‐year‐olds were higher when a contextual cue appeared at the beginning of the task (input gating) rather than at the end (output gating). This finding supports prior work in older children, suggesting that children are better when input gating but rely on the more effortful output gating strategy for goal‐oriented action selection (Cognition, 155, 2016 and 8). A manipulation was added to investigate whether children's use of working memory strategies becomes more flexible when task goals are specified internally rather than externally provided by the experimenter. A shift toward more proactive control was observed when children chose the task goal among two alternatives. Scan path analyses of saccadic eye movement indicated that giving children agency and choice over the task goal resulted in less use of a reactive strategy than when the goal was determined by the experimenter.  相似文献   

15.
内隐学习潜在机制研究的某些新进展   总被引:1,自引:0,他引:1  
内隐学习需要一定的注意和工作记忆参与,但关于它们影响内隐学习过程的潜在机制尚存在争议;随着内隐序列学习研究的深入,研究们开始关注序列知识的表征问题,这为揭示内隐知识的潜在表征机制开辟了新的途径;有关内隐学习神经机制的研究表明,基底神经节、联合区、额叶在内隐学习中起重要作用。  相似文献   

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There is an ongoing debate whether anti‐Muslim prejudice in Western countries is more widespread than prejudice towards other ethno‐cultural groups or general ethnic prejudice. Previous research used different methodologies and yielded contradictory results. In this article, we combine a population‐based split‐sample survey experiment (N = 1,323), where half of the respondents judged items about Muslims and the other half statements about strangers, with an open question probing which groups respondents thought of when thinking about “strangers.” We furthermore extend previous research by not only focusing on general ethnic prejudice, but to differentiate between perceived trustworthiness, economic, cultural, and security threat. Our results strongly support the idea that the difference between the “chronic” and “contextual” salience of the target of prejudice should be taken into account.  相似文献   

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The challenge of climate change for the South Pacific Island of Kiribati demands a 21st‐century missional vision to help respond effectively to the hopes and fears of islanders. This article employs a “coconut theology” embedded within an Indigenous knowledge thought‐system and the daily cultural experiences of the Kiribati people. Using coconut theology as a qualitative method, this study views climate songs as a source of primary data. The songs are collected and analyzed through a thematic approach. The findings demonstrate that songs play a critical role in the Kiribati people’s culture, keeping their voice alive and helping them make sense of their experiences of climate change. Based on the findings, the article argues that climate change songs embody critical theologies that could help the church embrace Indigenous imagination in its search for contextual relevance and effective response to climate change.  相似文献   

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