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981.
Coard SI  Nitz K  Felice ME 《Adolescence》2000,35(137):193-200
First-time adolescent mothers are at high risk for a repeat pregnancy. The present investigation, part of an ongoing longitudinal study, examined sociodemographic, family, and health factors associated with repeat Pregnancy in a clinic sample of urban, first-time adolescent mothers (ages 13 to 17 years). They were predominantly African-American and from low-income households. Repeat pregnancy within one year and between one and two years postpartum was determined from medical records. Summary statistics, point biserial correlations, and chi-square statistics were used to analyze the data. Results indicated that postpartum contraceptive method was associated with repeat pregnancy at Year 1; contraceptive use, maternal age, history of miscarriages, and postpartum contraceptive method were associated with repeat pregnancy at Year 2. It was concluded that efforts to prevent repeat pregnancies among first-time adolescent mothers should include the continuous monitoring of contraceptive use, as well as the promotion of long-acting contraceptives (e.g., medroxyprogesterone or progesterone implants). Further, counseling should be offered to adolescent mothers with a history offered miscarriages.  相似文献   
982.
The interaction of strong aggressive and libidinal drives, various primitive intrapsychic fantasies linking somatic sensations, body parts, ego, object, and the effects of early environmental stress and trauma all produce a potential crisis in the paranoid-schizoid period of development. Certain innate methods of understanding somatic experiences as well as the interaction between internal and external reality lead to an unconscious triangulation of part objects. A frustrating, stimulating, or punitive "third" that blocks, nullifies, or overgratifies certain wishes then emerges as a pivotal object in the internal landscape. During the paranoid-schizoid, triadic process, there is a fluctuation between separation/individuation and de-differentiation/fusion. If the early triangulation process has been either exceedingly frustrating or overly stimulating in regards to "reaching the third" or "warding off the third," the infantile ego is fixed by aggressive and libidinal forces to de-differentiation experiences rather than to more separate and individuated ways of relating. Therefore, the later oedipal stage will be colored by excessive oral and anal conflicts and will be weighted on the side of primitive maneuvering based on splitting, projection, and introjection. When the child (and later the adult) becomes involved in oedipal situations marked by stimulation or frustration of triadic drives, there can be a regression to the earlier paranoid-schizoid triadic period. A case study was presented in which a patient struggled with a partial working through of these conditions in dreams and in the transference. This pulled her more in the direction of a differentiated Oedipal conflict and whole object functioning.  相似文献   
983.
From the perspective that disgust is a core feature of spider phobia, we investigated whether the treatment efficacy could be improved by adding a counterconditioning procedure. Women with a clinically diagnosed spider phobia (N = 34) were randomly assigned to the regular one-session exposure condition (EXP) or to the exposure with counterconditioning condition (CC). In the CC-condition tasty food-items were used during the regular exposure exercises and the participants' favourite music was played. Both treatment conditions appeared very effective in reducing avoidance behaviour and self-reported fear of spiders, strongly attenuated the disgusting properties of spiders and altered the affective evaluations in a positive direction. CC was not more effective in altering the affective valence of spiders than EXP and was not superior with respect to the long term treatment efficacy at 1 year follow up. Apparently, regular exposure treatment is already quite effective in altering the affective-evaluative component of spider phobia and it remains to be seen whether it is possible to further improve treatment outcome by means of procedures which are specifically designed to reduce the spiders' negative affective valence.  相似文献   
984.
Ridenour, Daley, and Reich conducted a series of factor analyses using the correlational matrix of the subscale scores of the Family Assessment Device (FAD), published in Family Process, December, 1999. They conclude that "the FAD subscales be reorganized from their current seven-subscale format" (p. 507). We propose that this suggestion for reorganization is premature and based on the inappropriate application of an "internal consistency" model of scale construction to the FAD. We further suggest that the most important criteria regarding an assessment instrument are those of reliability, validity, and clinical utility. In the absence of this kind of data regarding alternative organizations of the FAD, we believe that the original subscales remain the best choice.  相似文献   
985.
The effectiveness of a stimulus as a conditioned reinforcer depends on the temporal context of reinforcement, that is, the overall rate of reinforcement in the situation. The dominant view has been that context determines the learned value of a stimulus directly, according to delay-reduction theory. By contrast, the contextual choice model (CCM) maintains that value is independent of context and incorporates the effects of context on choice in the framework of the matching law. The authors report 2 experiments with pigeons as subjects that use transfer tests to assess the value of stimuli in the concurrent-chains procedure. Results strongly support the assumption of CCM that pigeons learn the temporal relations between events independently of context but that context modulates the expression of that learning as choice.  相似文献   
986.
In 4 experiments, relational structures were independently varied in stimulus and response sequences in a serial reaction time task. Moreover, the use of spatial and symbolic stimuli and responses was varied between experiments. In Experiment 1, spatial stimuli (asterisk locations) triggered spatial responses (keystrokes); in Experiment 2, spatial stimuli triggered symbolic responses (verbal digit naming); in Experiment 3, symbolic stimuli (digits) triggered keystrokes; and in Experiment 4, digits triggered verbal responses. The results showed that there is a remarkably stronger effect of relational structures in spatial sequences than in symbolic sequences, irrespective of whether stimulus or response sequences are concerned. This suggests that learning is particularly effective for sequences of spatial locations. It is argued that spatial learning is a critical determinant for the debate on perceptual and motor learning.  相似文献   
987.
Electroencephalograms were recorded in 22 men while solving tasks of visual-pattern completion and during mental relaxation. They were primed (by foregoing trials) to solve these tasks either in a predicative or functional mode of thinking. Predicative thinking required that in order to complete the pattern the subject had to get involved with the logic of the static structure of the pattern and therefore had to recognize the recurrence of certain features of the elements (e.g., shape, color, and size). Functional thinking required involvement in a dynamic reading of the logic of the pattern and therefore to search for operations and actions to be performed on the pattern elements (e.g., pushing, mirroring, and rotating). The EEG complexity during predicative thinking decreased in comparison to functional thinking and mental relaxation, with this reduction being most pronounced over the right parietal cortex. A reduction in dimensional complexity during functional thinking as compared to mental relaxation, which was concentrated over the left central cortex, although significant, was less clear. The reduced EEG complexity during predicative thought, dominant over the right hemisphere, could reflect increased competitive inhibition among respective cortical neuron assemblies in association with the visual analysis of static element features, converging upon those predicates relevant for the solution.  相似文献   
988.
For two-choice tasks in which stimulus and response locations vary along horizontal and vertical dimensions, the spatial compatibility effect is often stronger on the horizontal than vertical dimension. Umiltà and Nicoletti [(1990) Spatial stimulus-response compatibility (pp. 89–116). Amsterdam: North-Holland] attributed this right-left prevalence effect to an inability to code vertical location when horizontal codes are present simultaneously. Hommel [(1996) Perception & Psychophysics, 43, 102–110] suggested instead that it reflects a voluntary strategy. This study reports four experiments that examine this issue. Experiment 1 was a conceptual replication of Hommel's Experiment 1, with responses made on a numeric keypad and subjects instructed in terms of the vertical or horizontal dimension. The results replicated Hommel's findings that showed a right-left advantage with horizontal instructions; however, with vertical instructions, we found a benefit of vertical compatibility alone that he did not. This benefit for vertical compatibility alone was eliminated in Experiment 2 using a varied practice schedule similar to that used by Hommel. Experiment 3 showed right-left prevalence and a benefit of vertical compatibility alone, even with varied practice and vertical instructions, when subjects responded on perpendicularly arranged handgrips. These benefits were eliminated in Experiment 4 using Hommel's method of urging subjects to respond only in terms of the instructed dimension. With bimanual responses, right-left prevalence is a robust phenomenon that is evident when comparing across vertical and horizontal instructions and, when the right-left distinction is relatively salient, within the vertical instructions condition alone. Received: 4 February 2000 / Accepted: 5 May 2000  相似文献   
989.
Natural images     
Moorhead I  Trościanko T 《Perception》2000,29(9):1013-1015
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990.
Research on the hopelessness and self-esteem theories of depression (Abramson, Metalsky, & Alloy, 1989; Metalsky, Joiner, Hardin, & Abramson, 1993) suggests that HIV-infected persons with depressotypic attributional style (AS) and low self-esteem (SE) may be at risk for onset of a syndrome referred to as hopelessness depression (HD). In a prospective study conducted to test these theories, measures of anxiety and depression, AS, and SE were administered to 85 HIV+ and 43 HIV– men; symptoms were reassessed 6 months later. Results indicated that: (1) The interaction of AS, SE, and HIV status predicted change in HD symptoms, but not overall depression or anxiety symptoms; (2) HIV+ men with depressotypic AS and high SE had increased HD symptom levels while other men with high SE had decreased HD symptom levels; (3) HD symptoms remained stable over the 6-month interval among men with low SE; and (4) High SE predicted decreases in anxiety symptoms among HIV– men, but not among HIV+ men. Contrary to the study hypothesis, these findings suggest that among individuals with life-threatening illnesses such as HIV infection, those with depressotypic AS and high SE may be at highest risk for onset of HD.  相似文献   
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