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141.
This research examined the association of having a tattoo and engaging in premarital sexual intercourse. Data gathered from a convenience sample of 450 college students indicated that tattooed respondents were substantively and significantly more likely to be sexually active than nontattooed college students. Tattooed men became sexually active at a significantly earlier age than nontattooed men but no such difference was found between tattooed and nontattooed college women.  相似文献   
142.
A matching-to-position (MTP) paradigm was altered to influence the type of associations a rat would use to solve the task. Our main behavioral manipulation was the application of the differential outcomes procedure (DOP). The DOP involves correlating each to-be-remembered event with a distinct reward condition. This procedure results in the development of unique reward expectancies that enhance and guide choice behavior. Such distinct reward expectancies are not formed when either a common or random assignment of reward is used (a non-differential outcomes procedure [NOP]). Intracerebroventricular infusions of the amnestic agent muscimol (GABA(A) agonist) or aCSF were delivered to male rats trained on a delayed MTP task that implemented either the DOP or the NOP. Muscimol impaired performance in a dose dependent fashion in both groups--but the nature of the deficit differed as a function of reinforcement contingencies. Rats trained with the DOP displayed a non-mnemonic delay-independent impairment: performance at all delay intervals was disrupted. In contrast, NOP-trained rats displayed a delay-dependent impairment demonstrating that muscimol can also have memory-disrupting effects. The difference in pattern of impairment appears to be a function of the associations formed during training and the type of cognitive strategies involved in maintaining behavior on a conditional delayed discrimination task when reinforcement contingencies are varied. Thus, these results demonstrate that increasing GABA(A) receptor activation impairs a range of associative and memory functions.  相似文献   
143.
OBJECTIVE: To develop a predictive model of the lift-off event during chair rise in healthy subjects, using foot-floor reaction forces. BACKGROUND: An important event during chair rise is lift-off from the seat: the transition from the inherently stable three-point contact to the unstable two-point contact. There is no consistent or generally agreed upon method for estimating the time of lift-off when an instrumented seat is unavailable. METHODS: Twenty healthy volunteers were divided into a testing set and training set. Each subject performed repeated chair rise trials at different speeds. Seat-floor and foot-floor forces, recorded with two force platforms, were used to develop a model of the lift-off event. RESULTS: The magnitude of the vertical foot-floor reaction at lift-off (F0VF) was linearly related (R2 = 0.71, P < 0.001) to the peak vertical foot-floor reaction force (FMVF). A linear model was developed for the training group, which enabled prediction of lift-off time for the testing group with an absolute average error of 6 ms (about 1 data frame at 150 Hz). The linear model derived for the entire sample was: F0VF = 28.14 + FMVF * (0.6434). CONCLUSIONS: The lift-off event for healthy subjects performing chair rise can be accurately predicted from foot-floor reaction forces, without requiring an instrumented seat.  相似文献   
144.
A growing body of literature suggests that individuals who face life-threatening situations turn to religion to help them cope. Religion has been cited as the most frequently used resource to cope with stressful events (K. I. Pargament, 1997). The present study was the first to investigate the religious coping methods of patients with lung disease who are awaiting transplant and to identify which coping methods are associated with distress and disability. The study was an exploratory, cross-sectional analysis of 90 patients with end-stage pulmonary disease who were being evaluated for transplant. Results indicated that religiosity was highly prevalent. Patients employed a combination of religious coping efforts, but mostly used coping methods considered positive. Patients with late-onset pulmonary diseases used religious coping strategies more frequently than patients with cystic fibrosis. Hierarchical regression analyses identified a subset of religious coping strategies that predicted 27%, 14%, and 34% of the unique variance in depression, overall disability, and psychosocial disability, respectively.  相似文献   
145.
The hippocampus appears to be critical for the formation of certain types of memories. Hippocampal-lesioned animals fail to exhibit some spatial, contextual, and relational associations. After aspiration lesions of the hippocampus and/or cortex, male rats were allowed to recover for three weeks before being trained on a matching-to-position task. The matching-to-position task was altered to influence the type of cognitive strategies a subject would use to solve the task. The main behavioral manipulation was the reinforcement contingency assignment: Use of a differential outcomes procedure (DOP) or a nondifferential outcomes procedure (NOP). The DOP involves correlating each to-be-remembered event with a distinct reward condition via Pavlovian trace conditioning, whereas the NOP results in random reward contingency. We found that hippocampal lesions did retard learning the matching rule, regardless of the reinforcement contingency assignment. However, when delay intervals were added to the task memory performance of subjects with hippocampal lesions was dramatically impaired--if subjects were not trained with the DOP. When subjects were trained with the DOP, the hippocampal lesion had a marginal effect on delayed memory performance. These findings demonstrate two important points regarding lesions of the hippocampus: (1) hippocampal lesions have a minimal effect on the on the ability of rats to use reward information to solve a delayed discrimination task; (2) rats with hippocampal lesions have the ability to learn about reward information using Pavlovian trace conditioning procedures.  相似文献   
146.
147.
Results obtained with functional magnetic resonance imaging show that both feeling a moderately painful pinprick stimulus to the fingertips and witnessing another person’s hand undergo similar stimulation are associated with common activity in a pain-related area in the right dorsal anterior cingulate cortex (ACC). Common activity in response to noxious tactile and visual stimulation was restricted to the right inferior Brodmann’s area 24b. These results suggest a shared neural substrate for felt and seen pain for aversive ecological events happening to strangers and in the absence of overt symbolic cues. In contrast to ACC 24b, the primary somatosensory cortex showed significant activations in response to both noxious and innocuous tactile, but not visual, stimuli. The different response patterns in the two areas are consistent with the ACC’s role in coding the motivational-affective dimension of pain, which is associated with the preparation of behavioral responses to aversive events.  相似文献   
148.
This study examined diagnostic predictors of prospectively observed suicide attempts in a personality disorder (PD) sample. During 2 years of follow-up, 58 participants (9%) reported at least 1 definitive suicide attempt. Predictors that were examined include 4 PD diagnoses and selected Axis I diagnoses (baseline and course). Multivariate logistic regression analyses indicated that baseline borderline personality disorder (BPD) and drug use disorders significantly predicted prospective suicide attempts. Controlling for baseline BPD diagnosis, proportional hazards analyses showed that worsening in the course of major depressive disorder (MDD) and of substance use disorders in the month preceding the attempt were also significant predictors. Therefore, among individuals diagnosed with PDs. exacerbation of Axis I conditions, particularly MDD and substance use, heightens risk for a suicide attempt.  相似文献   
149.
This study examined the effects of the Bayley Scales of Infant Development (BSID) version on developmental outcomes among drug-exposed children, some of whom received an intervention. Developmental outcome was evaluated with the BSID at 12 and 18 months and with the BSID-II at 24 and 30 months. In the repeated measures analyses, children scored higher on the BSID Mental Developmental Index (MDI; p < .01) and Psychomotor Developmental Index (PDI; p < .01) than on the BSID-II MDI and PDI. Version x Time (p < .01) and Version x Group (p < .01) interactions were also found for the MDI but not the PDI. PDI scores decreased on both the BSID and the BSID-II (p < .01). Over the first 2 years postpartum, mean MDI and PDI scores decreased among these high-risk, drug-exposed children.  相似文献   
150.
Two studies are presented that investigated the constraints underlying working memory performance in children and adults. In each case, independent measures of processing efficiency and storage capacity are assessed to determine their relative importance in predicting performance on complex span tasks,which measure working memory capacity. Results show that complex span performance was independently constrained by individual differences in domain-general processing efficiency and domain-specific storage capacity. Residual variance, which may reflect the ability to coordinate storage and processing, also predicted academic achievement. These results challenge the view that complex span taps a limited-capacity resource pool shared between processing and storage operations. Rather, they are consistent with a multiple-component model in which separate resource pools support the processing and storage functions of working memory.  相似文献   
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