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作业中断会对中断后行为绩效产生影响,探讨不同疲劳状态下中断对作业绩效影响的认知机制将有助于完善和发展中断的认知理论。本研究采用事件相关电位(ERP),通过在不同心理疲劳状态下执行数学题任务中断、暂停中断和不中断的空间2-back任务,结合行为数据和ERPs结果,分析作业中断对任务绩效的影响以及心理疲劳在其中的调节作用。实验结果发现,中断后诱发的P200和P300振幅显著提高,作业中断使得主任务的注意力资源下降,任务中断的无关信息干扰了主任务工作记忆,而疲劳状态则进一步加剧了中断对注意资源、工作记忆及行为绩效的负面效应。本研究在揭示作业中断认知过程及疲劳对其影响机理的同时,也支持了中断的目标记忆模型。  相似文献   
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基于ABR模型考察奖赏预期和奖赏结果对不同难度词对记忆与元记忆的影响。结果发现:(1)限时学习条件下,奖赏结果促进不同难度词对记忆成绩和学习判断,奖赏预期仅提高简单词对的记忆成绩。(2)自定步调学习条件下,定时学习判断时奖赏结果仅影响学习判断;奖赏预期促进高难度词对的学习时间分配,从而提高记忆成绩和学习判断。(3)在自定步调学习时,奖赏预期超越难度成为影响学习时间分配的因素。以上结果表明,个体会综合奖赏预期、奖赏结果和难度构建学习议程,足够大的奖赏预期会超越难度成为议程构建的主导因素。但奖赏预期和奖赏结果对记忆成绩、学习时间分配和学习判断的影响受学习条件调节。  相似文献   
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A systematic review of qualitative studies was conducted to explore how parents perceive sleep quality in their infants aged 0–24 months and the factors that influence these perceptions. A systematic search of the databases Scopus, Embase, Cinahl, PsycInfo and MEDLINE, was undertaken to identify eligible peer-reviewed studies published between 2006–2021. Ten papers met inclusion criteria and were subsequently included in the review. Evaluation of papers with the Critical Appraisal Skills Programme qualitative checklist classified papers as weak, moderate or strong, with half considered strong. Thematic synthesis identified one superordinate theme, culture, and five interrelated subordinate themes regarding how parents perceive their infant's sleep and the factors that may influence these perceptions. These themes were: (1) Infants physical and emotional comfort; (2) Beliefs regarding safety; (3) Parental and familial wellbeing; (4) Perceived degree of infant agency; (5) Influence of external beliefs and opinions. The findings from this review may assist practitioners in providing parents with personalized and culturally sensitive information regarding infant sleep and may also inform antenatal and early intervention practices, subsequently minimizing parental distress regarding infant sleep patterns.  相似文献   
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Episodic memory decline is the prominent neuropsychological feature of typical Alzheimer's Disease (AD), for which current treatments have a limited clinical response. Recently, gamma entrainment therapy has been used as a non-invasive treatment in AD, providing evidence that it may have the potential to alleviate brain pathology and improve cognitive function in AD patients. At the same time, the precuneus (PC) has been recognized as a key area involved in AD related memory deficits and as a key node of the Default Mode Network. This study aimed to investigate the effectiveness of a 40 Hz Transcranial Magnetic Stimulation (TMS) intervention, delivered bilaterally to the precuneus for 10 days, in improving the patients' episodic memory performance. Secondary outcome variables investigated included general cognitive function, semantic and spatial memory, as well as attention and executive function. A concurrent multiple baseline design across five cases was employed. Four patients completed the study. Visual analysis combined with effect size indices were used to evaluate changes across phases. An increase in the average level of immediate recalled words was observed in three out of four patients. Effect size indices indicated significant improvement of attention skills in two patients. No treatment effect was observed for semantic and visual memory, or for executive function. An immediate treatment effect was observed in all patients' general cognitive function as assessed with the Alzheimer's Disease Assessment Scale (mean reduction of 5 points), which was maintained and improved further three months post-treatment. The neuropsychological evaluations indicated improved performance three months post-treatment in immediate and delayed recall, attention, phonological verbal fluency, anxiety, and neuropsychiatric symptoms. This study provides preliminary evidence for the efficacy of a novel non-pharmacological treatment using gamma-band TMS in addressing cognitive dysfunction in AD.  相似文献   
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Previous studies of autobiographical memory (AM) in schizophrenia yielded a reduction of specificity, richness of details and conscious recollection, which indicate both, quantitative and qualitative AM changes. However, their associations with psychopathological symptoms and neuropsychological deficits were not resolved. Therefore, we sought to investigate AM with respect to psychopathology and neuropsychology in patients with chronic schizophrenia to rule out the influence of different courses of the disease. AM of four lifetime periods was examined in 75 patients and 50 healthy controls by using a semi-structured interview. The recalled episodes were rated for memory specificity. Subsequently, one single event of each period of life was rated for details and experiential aspects of reliving (originality, vividness/visual imagery, emotional re-experiencing and emotional valence). When contrasted with healthy controls, patients recalled a significantly reduced number of episodes and personal semantic facts; moreover, memory specificity of AM was significantly lower in patients than controls. While the richness of details calculated for single events showed only minor, non-significant group differences, vividness and emotional re-experiencing were significantly less pronounced in the patient group. Along with this, AM performance correlated significantly with negative symptoms including apathy as well as verbal memory and executive functions. Our results underline the significance of overgenerality as a key feature of AM in schizophrenia as well as a dissociation between intact number of details of single events and reduced vividness and emotional re-experiencing. The extent of negative symptoms including apathy and impairments of verbal memory/executive functions may explain AM deficits in chronic schizophrenia.  相似文献   
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The policies related to COVID-19 pandemic such as stay at home orders and social distancing increased daily stress and associated impairments in mental health. This study examines the association between COVID-related stress and cognitive functioning by examining two different types of daily memory lapses, those related to prospective memory (i.e., memory for future plans) and retrospective memory (i.e., memory for past information) as well as the perceived emotional and functional consequences of daily memory problems. As part of a larger study, 58 adults (18 men; 22 ± 3 years) completed a web-based version of the daily inventory of stressful events including stress related to COVID-19 and positive/negative affect for eight consecutive days between 8 September 2020 and 11 November 2020. Findings showed that prospective lapses were positively correlated with COVID-19 stressors (r = 0.41, p = 0.002). At the within-person level, daily COVID-19 stressors were significantly associated with the number of prospective lapses (b = 0.088, SE = 0.040). COVID-19-related stressors were not significantly related to retrospective lapses (all ps > 0.05). Our findings suggested that more daily COVID-19 stressors were related to greater numbers of prospective lapses in daily life even among healthy younger adults. Thus, future research should address long term relations of COVID-19 stress and cognitive functioning in addition to the specific cognitive impairments related to COVID-19 infection.  相似文献   
19.
Stroke is the main cause of acquired disability in adults, and specific deficits in working memory (WM) are among the most common cognitive consequences. In neuropsychological routine, WM is most of the time investigated in the framework of the multicomponent model (Baddeley & Hitch, 1974, The psychology of learning and motivation, 47). Using a more recent theoretical WM model, the time-based resource-sharing (TBRS) model (Barrouillet et al., 2011, Psychol. Rev., 118, 175), the aim of the present study was to investigate in young post-stroke patients to which extent attentional maintenance is impaired in WM. To address this question, we discarded other factors known to directly influence WM performance, that is processing speed and short-term memory span. We proposed to 53 post-stroke patients and to 63 healthy controls a complex span paradigm in which participants were asked to alternate between the memorization of a series of images and a concurrent parity judgement task of a series of digits. To investigate the attentional maintenance processes, we manipulated the cognitive load (CL) of the concurrent task. CL effect is typically interpreted as the involvement of attentional maintenance processes. The task was adapted to each participant according to their processing speed and memory span. As expected, the results showed higher recall performance in healthy controls compared with post-stroke patients. Consistent with the literature, we also observed higher performance when the CL was low compared with high. However, the improvement in recall at low CL was smaller for post-stroke patients compared with controls, suggesting that post-stroke WM deficit could be in part due to a deficit of the attentional maintenance processes.  相似文献   
20.
Sudden infant death syndrome (SIDS) is defined as the sudden and unexpected death of an apparently healthy infant under 1 year of age. Routine autopsies often provide few clues as to the cause of death and rarely include a biochemical evaluation. Genetic counseling for SIDS can be difficult as recurrence risks vary depending on the age at death and the number of deaths which have occurred in the family. Biochemical disorders may account for up to 5% of SIDS. Of the metabolic disorders known to be involved in SIDS, the most commonly found is medium-chain acyl CoA dehydrogenase deficiency (MCAD). MCAD is an autosomal recessive disorder of fatty acid oxidation which accounts for up to 1% of SIDS. For some families, the addition of a postmortem biochemical investigation can identify an unsuspected metabolic disorder as the cause of death. Once the diagnosis is established, accurate genetic counseling can then be provided. Metabolic testing of the surviving siblings of victims of sudden death, and the subsequent identification of those due to MCAD can prevent the tragedy of recurrent SIDS in some families. In addition, screening the survivors of an acute life threatening event (ALTE) may also prevent a recurrence.  相似文献   
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