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81.
Generalization gradients have been investigated widely in animal conditioning experiments, but much less so in human predictive learning tasks. Here, we apply the experimental design of a recent study on conditioned fear generalization in humans (Lissek et al., 2008) to a predictive learning task, and examine the effects of a number of relevant procedural parameters drawn from the generalization literature in animal conditioning. Experiment 1 shows that prior discrimination learning and steady-state testing procedures sharpen the gradient; Experiment 2 shows that within-subjects testing of the range of generalization stimuli also sharpens the gradient. In addition, Experiment 2 shows that, in case of very flat initial generalization, an orderly gradient can reveal itself through differential rates of extinction learning. Finally, Experiment 2 also evidenced an orderly gradient of generalization-of-extinction. These results suggest that discrimination processes have an important effect on the generalization of predictive learning in humans, and highlight behavioral analogies between animal conditioning and human predictive learning.  相似文献   
82.
In this paper we study some questions concerning ?ukasiewicz implication algebras. In particular, we show that every subquasivariety of ?ukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite ?ukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains.  相似文献   
83.
84.
The results of this study are part of an investigation to determine whether the cognitive-emotional process of emotional recognition is deficient as a function of the clinical condition and alexithymia in subjects with somatization. This investigation applied the self-assessment of emotion and used a procedure that minimizes the use of verbal skills and verbal comprehension. The specific goal of this study was to verify whether there were differences in the covariation between alexithymia and self-evaluation of the emotional reaction in clinical and nonclinical subjects. The results of this study highlight the significant differences between clinical and control subjects. There were inverse significant correlations with the affective valence in clinical subjects, whereas in the ratings of the TAS-20 in control subjects, there were direct correlations with activation. In the conclusions, we discuss whether the variability of the results of previous research of the relationship between alexithymia and emotional recognition is a characteristic feature of this relationship or an effect of the different sampling and procedures utilized.  相似文献   
85.
Although homework completion is said to be rather important to achievement, nowadays there is a growing concern of educators about the increasing number of students who do not engage properly on doing the homework tasks and the subsequent impact on school failure rates. Focusing on English as a Foreign Language (EFL) and using a sample of 591 Portuguese fifth and sixth graders, the present study analyses the role played by a number of homework variables on students' achievement (proximal and distal), and their mediating role on the use of self-regulated learning strategies and perceived self-efficacy in the domain. Data confirm the indirect effect of homework on school achievement, by means of the referred cognitive and motivational variables (use of self-regulated learning strategies and self-efficacy). These findings are further discussed in order to highlight the significant role homework completion can play on fighting school failure.  相似文献   
86.
This paper tests the efficacy of an intervention program in virtual format intended to train studying and self-regulation strategies in university students. The aim of this intervention is to promote a series of strategies which allow students to manage their learning processes in a more proficient and autonomous way. The program has been developed in Moodle format and hosted by the Virtual Campus of the University of Oviedo. The present study had a semi-experimental design, included an experimental group (n=167) and a control one (n=206), and used pretest and posttest measures (self-regulated learning strategies' declarative knowledge, self-regulated learning macro-strategy planning-execution-assessment, self-regulated learning strategies on text, surface and deep learning approaches, and academic achievement). Data suggest that the students enrolled in the training program, comparing with students in the control group, showed a significant improvement in their declarative knowledge, general and on text use of learning strategies, increased their deep approach to learning, decreased their use of a surface approach and, in what concerns to academic achievement, statistically significant differences have been found in favour of the experimental group.  相似文献   
87.
The purpose of this work was to determine the epidemiological evolution of the Oppositional Defiant Disorder (ODD) in adolescents, using a sample of Secondary School students of the region of Campo de Gibraltar (Cadiz). The students' age ranged from 12 to 16 years old. Two evaluations were completed, the first one during the school year 2001-2002 and the second one in the school year 2006-2007. The sample comprised 2310 students in the first study and 2351 students in the second one. We used a comparative-selective approach. The results of the comparison revealed a prevalence ranging from 3.77% to 3.83% of students with this disorder, maintaining the main symptoms and with some changes in its distribution as a function of the school grade. Indeed, the data showed more cases in the final courses (1st study) in contrast with a higher concentration of cases in the initial courses (2nd study). With regard to the frequency of ODD by sex, we found that whereas in the earlier study (2001-2002), the relationship between boys and girls was 3.5:1, in the school year 2006/2007, the number of boys with ODD quadrupled the number of girls.  相似文献   
88.
Psychological interventions in cocaine dependent patients have demonstrated efficacy. Remarkable approaches are Contingency Management (CM) and Cognitive Behavioral Therapy (CBT). Lack of treatment adherence is the most important limitation. Motivational Interview (MI) has been shown to be an adherence enhancer. The objective of this study is to evaluate retention and abstinence in a combined CM and CBT group treatment in patients who have reached maintenance stage according to Prochaska and DiClemente's transtheoretical model (1982). Therefore, a longitudinal study was carried out with cocaine dependent patients with or without concomitant mental health disease. A 12-session open group was conducted weekly. Nineteen patients were included (78.9% men, mean age 36.6 years), 95% consumed intranasally and 47% had another psychiatric comorbidity. Treatment retention was 84%. During treatment and the first month of follow-up, all patients remained abstinent whereas at three months, 3 patients relapsed. These data confirm that using combined CM and CBT group therapy in cocaine dependents undergoing maintenance treatment enhances adherence and is effective to achieve abstinence.  相似文献   
89.
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH+, and 10 without, WMH) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH+ and WMH - in right parietal and bilateral temporal areas. Both WMH and WMH+ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH+ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood.  相似文献   
90.
Relational processing involves learning about the relationship between or among stimuli, transcending the individual stimuli, so that abstract knowledge generalizable to novel situations is acquired. Relational processing has been studied in animals as well as in humans, but little attention has been paid to the contribution of specific items to relational thinking or to the factors that may affect that contribution. This study assessed the intertwined effects of item and relational processing in nonhuman primates. Using a procedure that entailed both expanding and contracting sets of pictorial items, we trained 13 baboons on a two-alternative forced-choice task, in which they had to distinguish horizontal from vertical relational patterns. In Experiment 1, monkeys engaged in item-based processing with a small training set size, and they progressively engaged in relation-based processing as training set size was increased. However, in Experiment 2, overtraining with a small stimulus set promoted the processing of item-based information. These findings underscore similarities in how humans and nonhuman primates process higher-order stimulus relations.  相似文献   
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