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121.
Two experiments examined whether postsample signals of reinforcer probability or magnitude affected the accuracy of delayed matching to sample in pigeons. On each trial, red or green choice responses that matched red or green stimuli seen shortly before a variable retention interval were reinforced with wheat access. In Experiment 1, the reinforcer probability was either 0.2 or 1.0 for both red and green responses. Reinforcer probability was signaled by line or cross symbols that appeared after the sample had been presented. In Experiment 2, all correct responses were reinforced, and the signaled reinforcer durations were 1.0 s and 4.5 s. Matching was more accurate when larger or more probable reinforcers were signaled, independently of retention interval duration. Because signals were presented postsample, the effects were not the result of differential attention to the sample. 相似文献
122.
Encoding action phrases by enacting leads normally to better memory performance than verbal encoding. In order to gain additional insight into the representational basis of the enactment effect, neurological patients are contrasted with healthy participants. Persons suffering from Parkinson's disease, which primarily impairs the motor system, and patients suffering from Frontal Lobe Syndrome, which primarily affects action-related planning processes, were involved. We investigated whether the enactment effect would be differentially affected by these disorders. In addition, the characteristics of information processing after encoding by enacting was analyzed by varying memory material (unrelated versus clusterable actions) and by adding an encoding condition that included obligatory action planning (director condition). The findings indicate that the impact of motor information for the enactment effect is not dominant compared to the role of action-related cognitive and motivational processes, in particular planning processes. The findings of the two experiments are explained within traditional conceptual memory theories. 相似文献
123.
The purpose of this paper is to examine the effectiveness of Reconnecting Youth, a prevention program for at-risk high school youth. Data are from a large, independently evaluated effectiveness trial in two diverse urban school districts. A total of 1,218 students participated; 50% were male; average age was 15. We tested whether positive efficacy trial effects could be replicated, and whether any negative behavioral effects occur when clustering high-risk youth. Although mixed program effects were observed at immediate post-intervention, only negative effects were found at 6-month follow-up. These effects included less optimal scores on measures of GPA, Anger, School Connectedness, Conventional Peer Bonding, and Peer High-Risk Behaviors. Overall, we found little support for the use of this social-influence—model intervention aimed at increasing school connectedness for high-risk youth. Further, this study provides evidence that clustering high-risk youth in preventive interventions has the potential for iatrogenic effects. 相似文献
124.
Confirmatory factor analysis (CFA) was used to model a multitrait by multisource matrix to determine the convergent and discriminant validity of measures of attention-deficit hyperactivity disorder (ADHD)-inattention (IN), ADHD-hyperactivity/impulsivity (HI), and oppositional defiant disorder (ODD) in 917 Malaysian elementary school children. The three trait factors were ADHD-IN, ADHD-HI, and ODD. The two source factors were parents and teachers. Similar to earlier studies with Australian and Brazilian children, the parent and teacher measures failed to show convergent and discriminant validity with Malaysian children. The study outlines the implications of such strong source effects in ADHD-IN, ADHD-HI, and ODD measures for the use of such parent and teacher scales to study the symptom dimensions. 相似文献
125.
The aim of this study was to examine the masculinity and femininity scales of Bem Sex Role Inventory (BSRI) among Turkish university students. Five hundred thirty-six students (280 men and 256 women) volunteered to complete the short-form of the BSRI and answer demographic questions. In factor analyses, the original factor structure (Bem, 1981) was found both in the mens and womens data. Comparisons of the factor structures with target rotation (Procrustes rotation) and comparison indexes showed no difference between the factor structures found among men and women. The internal consistency of the masculinity and femininity scales was acceptable, and t-tests showed that women scored higher on the femininity scale, and men scored higher on the masculinity scale. There were significant differences between men and women only on two masculinity items, but significant differences were found in 8 (of 10) femininity items. 相似文献
126.
The new correlated 8-factor measurement structure of the Child Behavior Checklist for ages 6-18 (CBCL/6-18; T. M. Achenbach & L. A. Rescorla, 2001) derived from an American sample was used as a benchmark to evaluate its generalizability to Turkish general population (N = 5,195) and clinical (N = 963) samples. Item-level confirmatory factor analysis (CFA) was used to evaluate the adequacy of the correlated 8-factor model across 3 sample conditions (general population, clinical, and combined sample whose Total Problems scores were above the Turkish national median). The results supported the generalizability of the overall measurement structure of the CBCL to the Turkish population. 相似文献
127.
McIntyre A 《Theoretical medicine and bioethics》2004,25(1):61-74
The U.S. Supreme Court's majorityopinion in Vacco v. Quill assumes thatthe principle of double effect explains thepermissibility of hastening death in thecontext of ordinary palliative care and inextraordinary cases in which painkilling drugshave failed to relieve especially intractablesuffering and terminal sedation has beenadopted as a last resort. The traditionaldoctrine of double effect, understood asproviding a prohibition on instrumental harmingas opposed to incidental harming or harming asa side effect, must be distinguished from otherways in which the claim that a result is notintended might be offered as part of ajustification for it. Although double effectmight appropriately be invoked as a constrainton ordinary palliative care, it is not clearthat it can be coherently extended to justifysuch practices as terminal sedation. A betterapproach would reconsider double effect'straditional prohibition on hastening death as ameans to relieve suffering in the context ofacute palliative care. 相似文献
128.
Marshall MF 《Science and engineering ethics》2004,10(1):37-42
This paper gives an overview of the placebo effect in popular culture, especially as it pertains to the work of authors Patrick
O’Brian and Sinclair Lewis. The beloved physician as placebo, and the clinician scientist as villain are themes that respectively
inform the novels, The Hundred Days and Arrowsmith. Excerpts from the novels, and from film show how the placebo effect, and the randomized clinical trial, have emerged into
popular culture, and evolved over time.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
129.
Szawarski Z 《Science and engineering ethics》2004,10(1):57-64
This paper attempts to define the concept of placebo as it is used in the clinical context The author claims that X is a placebo
if and only if X has such a property dp, that whenever in a therapeutic situation T a stimulus S appears, then in attending conditions A, it will cause a beneficial
reaction R in the patient. Formally, the same structure may be used to define any pharmacologically active drug. The main
difference between the drug and a placebo is in the range of possible substitutions for X and the property d. For the active
drug there is only one possible substitution for X and property d and it can be scientifically explained why, and how the
drug works. In the case of a placebo a set of possible substitutions for X and d is open, and so far it is impossible to offer
any scientifically valid explanation of the action mechanism of placebo. 相似文献
130.
Rambo (1993) theorized that religious conversion consists of a process involving seven dimensions, labeled context, crisis, quest, encounter, interaction, commitment, and consequences. To test the Rambo model, a new measure, the 97-item Adult Religious Conversion Experiences Questionnaire (ARCEQ), was developed, revised on the basis of feedback from a focus group, and administered by mail to 110 adult volunteers who self-identified as having experienced conversion. Reliability analysis of the subscales of the ARCEQ resulted in five (crisis, quest, encounter, commitment, and consequences) meeting the criterion ( > .80). A sixth (interaction) achieved a reliability of .76 and was retained, but the seventh (context) was dropped. Principal components factor analysis with Varimax rotation produced factors labeled Redemptive Love, Zealous Dedication, Dysphoric Need, Openness to Uncertainty, Extrinsic Crisis, and Experiential Learning, which could readily be interpreted in relation to Rambo's model. Subsidiary analyses showed a number of significant correlations between demographic characteristics of the sample and differences in religious conversion experience. 相似文献