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991.
The purpose of this study was to investigate the effects of signaled transitions from relatively rich to lean conditions of food reinforcement on drinking concurrently available water or sucrose‐sweetened water in rats. Past research demonstrated that these negative incentive shifts produce behavioral disruption in the form of extended pausing on fixed‐ratio schedules. Four male Long‐Evans rats operated on a two‐component multiple fixed‐ratio fixed‐ratio schedule. In one manipulation, the ratio was held constant and the components arranged either a large six‐pellet reinforcer (rich) or small one‐pellet reinforcer (lean). In a second manipulation, the components both produced a one‐pellet reinforcer but differed in terms of the ratio requirement, with the rich and lean conditions corresponding to relatively small and large ratios. In both manipulations, components were pseudorandomly presented to arrange four transitions signaled by retractable levers: lean‐to‐lean, lean‐to‐rich, rich‐to‐rich, and rich‐to‐lean (the negative incentive shift). During experimental conditions, a bottle with lickometer was inserted in the chamber, providing concurrent access either to tap water or a 10% sucrose solution. The negative incentive shift produced considerably more drinking than the other transitions in all rats during both manipulations. The level of drinking was not polydipsic; rather, it appears that the negative incentive shift enhanced the value of concurrently available reinforcers relative to food reinforcement.  相似文献   
992.
Extended pausing during discriminable transitions from rich‐to‐lean conditions can be viewed as escape (i.e., rich‐to‐lean transitions function aversively). In the current experiments, pigeons’ key pecking was maintained by a multiple fixed‐ratio fixed‐ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition‐specific stimulus used in the multiple schedule to a mixed‐schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2). Overall, escape was under joint control of past and upcoming reinforcer magnitudes, such that responses on the escape key were most likely during rich‐to‐lean transitions, and second‐most likely during lean‐to‐lean transitions. Even though pigeons pecked the escape key, they paused before doing so, and the latency to begin the fixed ratio (i.e., the pause) remained extended during rich‐to‐lean transitions. These findings suggest that although the stimulus associated with rich‐to‐lean transitions functioned aversively, pausing is more than simply escape responding from the stimulus.  相似文献   
993.
Prolonged space flight, specifically microgravity, presents a problem for space exploration. Animal models with altered connections of the vestibular ear, and thus altered gravity sensation, would allow the examination of the effects of microgravity and how various countermeasures can establish normal function. We describe an experimental apparatus to monitor the effects of ear manipulations to generate asymmetric gravity input on the tadpole escape response. To perform the movement pattern analysis, an imaging apparatus was developed that uses a high‐speed camera to obtain time‐resolved, high‐resolution images of tadpole movements. Movements were recorded in a temperature‐controlled test chamber following mechanical stimulation with a solenoid actuator, to elicit a C‐start response. Temperature within the test cell was controlled with a recirculating water bath. Xenopus laevis embryos were obtained using a standard fertilization technique. Tadpole response to a controlled perturbation was recorded in unprecedented detail and the approach was validated by describing the distinct differences in response between normal and one‐eared tadpoles. The experimental apparatus and methods form an important element of a rigorous investigation into the response of the tadpole vestibular system to mechanical and biochemical manipulations, and can ultimately contribute to improved understanding of the effects of altered gravity perception on humans.  相似文献   
994.
The period during which grown children leave home and establish a new, self‐supporting family is called emerging adulthood. This paper uses psychoanalytic concepts and family‐life‐cycle theory to analyze the film Rebel without a Cause ( 1955 ) as a dramatic example of three families going through this phase. Freud's ( 1910 ) rescue‐motif of the child trying to save an endangered peer to repay his parents for having been nurtured is also characteristic of this period and is considered practice for parenting the next generation. Proximate conflict and support enable two of the film's families to continue the path to reproduce themselves.  相似文献   
995.
This paper addresses the radical departure of late Bion's and Winnicott's clinical ideas and practices from traditional psychoanalytic work, introducing a revolutionary change in clinical psychoanalysis. The profound significance and implications of their thinking are explored, and in particular Bion's conception of transformation in O and Winnicott's clinical‐technical revision of analytic work, with its emphasis on regression in the treatment of more disturbed patients. The author specifically connects the unknown and unknowable emotional reality‐O with unthinkable breakdown (Winnicott) and catastrophe (Bion). The author suggests that the revolutionary approach introduced by the clinical thinking of late Bion and Winnicott be termed quantum psychoanalysis. She thinks that this approach can coexist with classical psychoanalysis in the same way that classical physics coexists with quantum physics.  相似文献   
996.
Initial exertion of self‐control has been suggested to impair subsequent self‐regulatory performance. The specific cognitive processes that underlie this ego depletion effect have rarely been examined. Drawing on the dual‐process theory of executive control (Engle & Kane, 2004 ; Kane & Engle, 2003 ), the current meta‐analysis revealed that initial self‐control exertion impairs participants’ capacities of maintaining the task goal but its effect on capacities of resolving response competition is in need of further investigation. Our results are more consistent with recent theoretical views that consider ego depletion as a switch cost and a result arising from reduced motivation to engage in further self‐control.  相似文献   
997.
The reaction time has been described as a measure of perception, decision making, and other cognitive processes. The aim of this work is to examine age‐related changes in executive functions in terms of demand load under varying presentation times. Two tasks were employed where a signal detection and a discrimination task were performed by young and older university students. Furthermore, a characterization of the response time distribution by an ex‐Gaussian fit was carried out. The results indicated that the older participants were slower than the younger ones in signal detection and discrimination. Moreover, the differences between both processes for the older participants were higher, and they also showed a higher distribution average except for the lower and higher presentation time. The results suggest a general slowdown in both tasks for age under different presentation times, except for the cases where presentation times were lower and higher. Moreover, if these parameters are understood to be a reflection of executive functions, these findings are consistent with the common view that age‐related cognitive deficits show a decline in this function.  相似文献   
998.
Few group psychotherapy studies focus on therapists' interventions, and instruments that can measure group psychotherapy treatment fidelity are scarce. The aim of the present study was to evaluate the reliability of the Mentalization‐based Group Therapy Adherence and Quality Scale (MBT‐G‐AQS), which is a 19‐item scale developed to measure adherence and quality in mentalization‐based group therapy (MBT‐G). Eight MBT groups and eight psychodynamic groups (a total of 16 videotaped therapy sessions) were rated independently by five raters. All groups were long‐term, outpatient psychotherapy groups with 1.5 hours weekly sessions. Data were analysed by a Generalizability Study (G‐study and D‐study). The generalizability models included analyses of reliability for different numbers of raters. The global (overall) ratings for adherence and quality showed high to excellent reliability for all numbers of raters (the reliability by use of five raters was 0.97 for adherence and 0.96 for quality). The mean reliability for all 19 items for a single rater was 0.57 (item range 0.26–0.86) for adherence, and 0.62 (item range 0.26–0.83) for quality. The reliability for two raters obtained mean absolute G‐coefficients on 0.71 (item range 0.41–0.92 for the different items) for adherence and 0.76 (item range 0.42–0.91) for quality. With all five raters the mean absolute G‐coefficient for adherence was 0.86 (item range 0.63–0.97) and 0.88 for quality (item range 0.64–0.96). The study demonstrates high reliability of ratings of MBT‐G‐AQS. In models differentiating between different numbers of raters, reliability was particularly high when including several raters, but was also acceptable for two raters. For practical purposes, the MBT‐G‐AQS can be used for training, supervision and psychotherapy research.  相似文献   
999.
Using a non‐alphabetic language (e.g., Chinese), the present study tested a novel view that semantic information at the sublexical level should be activated during handwriting production. Over 80% of Chinese characters are phonograms, in which semantic radicals represent category information (e.g., 椅 ‘chair,’ 桃 ‘peach,’ 橙 ‘orange’ are related to plants) while phonetic radicals represent phonetic information (e.g., 狼 ‘wolf,’ 朗 ‘brightness,’ 郎 ‘male,’ are all pronounced /lang/). Under different semantic category conditions at the lexical level (semantically related in Experiment 1; semantically unrelated in Experiment 2), the orthographic relatedness and semantic relatedness of semantic radicals in the picture name and its distractor were manipulated under different SOAs (i.e., stimulus onset asynchrony, the interval between the onset of the picture and the onset of the interference word). Two questions were addressed: (1) Is it possible that semantic information could be activated in the sublexical level conditions? (2) How are semantic and orthographic information dynamically accessed in word production? Results showed that both orthographic and semantic information were activated under the present picture‐word interference paradigm, dynamically under different SOAs, which supported our view that discussions on semantic processes in the writing modality should be extended to the sublexical level. The current findings provide possibility for building new orthography‐phonology‐semantics models in writing.  相似文献   
1000.
In this study the levels of experienced burnout of Finnish and Chinese university students are compared using School Burnout Inventory (SBI). This study is motivated by earlier studies, which suggest that the level of student burnout is different in the culturally distinct Finnish and Chinese university systems, but which are based on different research instruments for the two groups. The sample studied consisted of 3,035 Finnish students and 2,309 Chinese students. Because of the cross‐cultural nature of this study the level of structural equivalence of SBI between the cultural groups was examined and the effect of different response styles on the results was taken into account. Both standard and robust statistical methods were used for the analyses. The results showed that SBI with two extracted components is suitable for cross‐cultural analysis between Finnish and Chinese university students. Virtually no difference was found in experienced overall burnout between the Finnish and Chinese students, which means that both university systems contain factors causing similar levels of student burnout. This study also verified that controlling for the response styles is important in cross‐cultural studies as it was found to have a distinct effect on the results obtained from mean‐level comparisons.  相似文献   
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