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981.
982.
983.
Family Re-Union is an ongoing conference series and family policy initiative launched in 1992 by Al and Tipper Gore. It has been the springboard for a new wave of family-centered community building efforts, including the development of an educational program to prepare a new generation of community builders. We summarize the history of this family-centered community building movement and discuss how it builds upon and differs from earlier approaches to community development. We describe Family Re-Union and some of the ongoing work it has fueled. And we suggest ways family professionals can take part in this work. 相似文献
984.
The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational variables. A functional relation between environmental arrangement and reusable product selection was demonstrated in a reversal design. However, the largest effect occurred as function of a multicomponent intervention involving environmental arrangement, employee involvement, and personal spoken prompts with motivational signs. The results support the use of informant assessments when designing community interventions. 相似文献
985.
Two experiments with pigeons investigated the effects of contingencies between interresponse times (IRTs) and the transitions between the components of 2- and 4-component chained schedules (Experiments 1 and 2, respectively). The probability of component transitions varied directly with the most recent (Lag 0) IRT in some experimental conditions and with the 4th (Lag 4) IRT preceding the most recent one in others. Mean component durations were constant across conditions, so the reinforcing effect of stimulus change was dissociated from that of delay to food. IRTs were longer in the Lag-0 than in the Lag-4 conditions of both experiments, thus demonstrating that stimulus change functioned as a reinforcer. In the Lag-0 conditions of Experiment 2, the Component-1 IRTs increased more than the Component-2 IRTs, which in turn increased more than the Component-3 IRTs. This finding runs counter to the conditioned-positive-reinforcement account of chained-schedule responding, which holds that the reinforcing effect of stimulus change should vary in strength as an inverse function of the delay to the unconditioned reinforcer at the end of the chain because conditioned reinforcement is due to first- or higher-order classical conditioning. Therefore, we present other possible explanations for this effect. 相似文献
986.
The effect of force requirements on response effort was examined using outbred (CD-1) mice trained to press a disk with their snout. Lateral peak forces greater than 2 g were defined as threshold responses (i.e., all measured responses). Different force requirements were used to define criterion responses (a subclass of threshold responses) that exceeded the requirement. The reinforcer was sweetened, condensed milk, and it was delivered upon response termination. All mice were exposed to two ascending series of criterion force requirements (2, 4, 8, 16, and 32 g). Increasing the force requirement decreased criterion response rates, but increased threshold response rates. The time-integral of force (area under the force-time curve for individual responses, which is proportional to energy expenditure for each response) increased with the increase in the force requirement. These results conflict with the hypothesis that higher force requirements have aversive qualities and suggest that increased force requirements are more analogous to intermittent schedules of reinforcement. These data suggest that estimations of effort or energy expenditure should be measured independently of the force requirement. Individual differences in responding were found for the CD-1 outbred stock. 相似文献
987.
Forensic evaluations of offender populations often consider psychopathy as an integral component of these consultations. Vexing issues remain of whether psychopathic traits should be evaluated consistently irrespective of demographic characteristics (e.g. gender), comorbidity (e.g. other Axis II pathology), or setting (e.g. jail or community). The current study examined gender differences for psychopathy and Axis II traits in a nonreferred jail sample of predominantly nonviolent offenders. Participants with moderate to high levels of psychopathy evidenced substantial comorbidity, especially with Cluster B personality disorders. Facets of psychopathy and Axis II traits varied substantially across both genders. In addition, the research evaluated Lynam's Hyperactivity, Impulsivity, and Attention difficulties (HIA) model of psychopathy. These initial data found little support for the HIA model in this jail sample. In testing competing hypotheses, the HIA model was substantially better at predicting Cluster B traits than psychopathy per se. 相似文献
988.
Farinelli M Deschaux O Hugues S Thevenet A Garcia R 《Learning & memory (Cold Spring Harbor, N.Y.)》2006,13(3):329-334
It has been shown that long-term potentiation (LTP) develops in the connection between the mediodorsal thalamus (MD) and the medial prefrontal cortex (mPFC) and between the hippocampus (HPC) and the mPFC following fear extinction, and correlates with extinction retention. However, recent lesion studies have shown that combined lesions of the MD and mPFC do not interfere with extinction learning and retention, while inactivation of the dorsal HPC disrupts fear extinction memory. Here we found in rats that immediate post-training HPC low-frequency stimulation (LFS) suppressed extinction-related LTP in the HPC-mPFC pathway and induced difficulties in extinction recall. HPC tetanus, applied several hours later, failed to re-establish mPFC LTP but facilitated recall of extinction. Delayed post-training HPC LFS also provoked mPFC depotentiation and difficulties with extinction recall. HPC tetanus abolished these two effects. We also found that damage to the mPFC induced fear return only in rats that received HPC LFS following extinction training. HPC tetanus also reversed this behavioral effect of HPC LFS in lesioned rats. These data suggest that the HPC interacts with the mPFC during fear extinction, but can modulate fear extinction independently of this interaction. 相似文献
989.
Palchykova S Winsky-Sommerer R Meerlo P Dürr R Tobler I 《Neurobiology of learning and memory》2006,85(3):263-271
Many studies in animals and humans suggest that sleep facilitates learning, memory consolidation, and retrieval. Moreover, sleep deprivation (SD) incurred after learning, impaired memory in humans, mice, rats, and hamsters. We investigated the importance of sleep and its timing in an object recognition task in OF1 mice subjected to 6h SD either immediately after the acquisition phase (0-6 SD) or 6h later (7-12 SD), and in corresponding undisturbed controls. Motor activity was continuously recorded with infrared sensors. All groups explored two familiar, previously encountered objects to a similar extent, both at the end of the acquisition phase and 24h later during the test phase, indicating intact familiarity detection. During the test phase 0-6 SD mice failed to discriminate between the single novel and the two familiar objects. In contrast, the 7-12 SD group and the two control groups explored the novel object significantly longer than the two familiar objects. Plasma corticosterone levels determined after SD did not differ from time-matched undisturbed controls, but were significantly below the level measured after learning alone. ACTH did not differ between the groups. Therefore, it is unlikely that stress contributed to the memory impairment. We conclude that the loss of sleep and the activities the mice engaged in during the SD, impaired recognition memory retrieval, when they occurred immediately after acquisition. The delayed SD enabled memory consolidation during the 6h when the mice were allowed to sleep, and had no detrimental effect on memory. Neither SD schedule impaired object familiarity processing, suggesting that only specific cognitive abilities were sensitive to the intervention. Sleep may either actively promote memory formation, or alternatively, sleep may provide optimal conditions of non-interference for consolidation. 相似文献
990.
Confidence intervals (CIs) give information about replication, but many researchers have misconceptions about this information. One problem is that the percentage of future replication means captured by a particular CI varies markedly, depending on where in relation to the population mean that CI falls. The authors investigated the distribution of this percentage for varsigma known and unknown, for various sample sizes, and for robust CIs. The distribution has strong negative skew: Most 95% CIs will capture around 90% or more of replication means, but some will capture a much lower proportion. On average, a 95% CI will include just 83.4% of future replication means. The authors present figures designed to assist understanding of what CIs say about replication, and they also extend the discussion to explain how p values give information about replication. 相似文献