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101.
This paper presents a new knowledge-acquisition system—the Case Experience Combination System (CECoS). With CECoS, two information or knowledge sources are jointly analyzed. Previously recorded problem solutions (individual cases) are combined with an expert’s high-level understanding of the global structure of a task domain. By combining the detailed case information with an expert’s general insights, CECoS provides the domain knowledge with which skeletal plans can be automatically constructed. 相似文献
102.
Pregnancy, while often marked by joy, may pose considerable risk for depression among parents. Against a backdrop of adverse life events, expectant parents may be even more vulnerable to developing symptoms of depression during the prenatal period. Thus, it is critical to identify sources of resilience that might facilitate a successful transition to parenthood among couples who have a history of adversity. Prior work suggests that interpersonal and intrapersonal factors associated with resilience, such as intimate relationship satisfaction and self-compassion (i.e., self-kindness, common humanity, and mindfulness), have the potential to attenuate prenatal depression among couples with a history of stressful life experiences. We tested this possibility in a sample of 159 couples navigating pregnancy. As predicted, a greater number of prior stressful life experiences was associated with increased depression symptom severity for both mothers and fathers. However, moderation analyses revealed the positive link between cumulative stressful life experiences and depression symptom severity was attenuated among mothers who reported greater self-compassion in the form of feelings of common humanity, and fathers who reported higher levels of intimate relationship satisfaction and self-compassion in the form of mindfulness. Findings suggest enhancing intimate relationship satisfaction and self-compassion among expectant couples may be valuable in attenuating prenatal depression among those with a greater history of adversity. 相似文献
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Hecht K Cornélissen G Fietze I Katinas G Herold M Halberg F 《Perceptual and motor skills》2002,95(1):258-266
This study aimed to describe quantitatively some changes in sleep behavior. During 70 consecutive nights, 28 women and 3 men, 30 to 40 years of age and presumably clinically healthy, recorded the time of each awakening. Time of falling asleep were estimated from markings at 10-min. intervals from the times of lying down to sleep as an indication that the subject had not yet fallen asleep. Sleep duration and an index of effective sleep derived therefrom were analyzed by rhythmometric methods. On a group basis, anticipated components with periods of 1 and 0.5 wk., synchronized with the social schedule, were detected with statistical significance. Until long-term polysomnographic monitoring can readily cover the week automatically rather than only one or a few daily sleep spans, the self-monitoring of sleep behavior, yielding the circaseptan endpoints derived herein, may serve as a cost-effective tool in sleep research. By virtue of their relative simplicity, they could be part of a protocol designed to assess pharmacologic or nonpharmacologic interventions of sleep disturbance aimed at restoring undisturbed sleep. 相似文献
107.
When the left and right hands produce 2 different rhythms simultaneously, coordination of the hands is difficult unless the rhythms can be integrated into a unified temporal pattern. In the present study, the authors investigated whether a similar account can be applied to the spatial domain. Participants (N = 8) produced a movement trajectory of semicircular form in single-limb and bimanual conditions. In the bimanual tasks, 1 limb moved above the other in the frontal plane. Bimanual unified tasks were constructed so that the spatial paths to be produced by the 2 limbs could be easily conceptualized as parts of a unified circle pattern. Bimanual distinct tasks availed a less obvious spatial pattern that would unify the 2 tasks, despite similar demands placed on the coordination dynamics in the 2 cases (e.g., the phase relations). The authors conclude that a dual task becomes a single task, and interlimb interference is reduced, when the spatial patterns produced by the 2 hands form a geometric arrangement that can be conceptualized as a unified representation. 相似文献
108.
Withdrawal from cocaine self-administration produces long-lasting deficits in orbitofrontal-dependent reversal learning in rats 下载免费PDF全文
Calu DJ Stalnaker TA Franz TM Singh T Shaham Y Schoenbaum G 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(5):325-328
Drug addicts make poor decisions. These decision-making deficits have been modeled in addicts and laboratory animals using reversal-learning tasks. However, persistent reversal-learning impairments have been shown in rats and monkeys only after noncontingent cocaine injections. Current thinking holds that to represent the human condition effectively, animal models of addiction must utilize self-administration procedures in which drug is earned contingently; thus, it remains unclear whether reversal-learning deficits caused by noncontingent cocaine exposure are relevant to addiction. To test whether reversal learning deficits are caused by contingent cocaine exposure, we trained rats to self-administer cocaine, assessed cue-induced cocaine seeking in extinction tests after 1 and 30 d of withdrawal, and then tested for reversal learning more than a month later. We found robust time-dependent increases in cue-induced cocaine seeking in the two extinction tests (incubation of craving) and severe reversal-learning impairments. 相似文献
109.
Engaging in musical training has been shown to result in long-term cognitive benefits. The authors examined whether basic cognitive-motor processes differ in people with extensive musical training and in nonmusicians. Musicians (n = 20) and nonmusicians (n = 20) performed a simple reaction time (RT) task under unimanual and bimanual conditions. Musicians' RTs were faster overall than were those of nonmusicians, and those who began their musical training at an earlier age (around age 7-8 years, on average) exhibited a larger bimanual cost than did those who began later (around 12 years, on average). The authors conclude that experience-dependent changes associated with musical training can result in greater efficacy of interhemispheric connections if those changes occur during certain critical periods of brain development. 相似文献
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