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221.
Selective breeding of wild rats over many generations on the basis of low or high defensive threat and attack to human approach and contact has produced highly polarized “domesticated” and “wild-type” animals. Because the selection procedure selectively involves these two defense patterns, and these clearly differ in the two groups, it is of interest to determine if other, nonselected, defensive behaviors to threat stimuli also change. “Domesticated” and “wild-type” rats of the thirty-fifth generation were run in a fear defense test battery (F/DTB) to systematically evaluate defensive behaviors to a variety of present threat stimuli. “Domesticated” rats showed reduced avoidance and slower flight speed to an approaching experimenter, reduced jump/startle response to handelap and dorsal contact, less vocalization and boxing to vibrissae stimulation or to an anesthetized conspecific, and reduced defensiveness to an attempted pickup by the experimenter. These results indicate that selective bi-directional breeding for defensive threat and attack to human approach and contact produces group differences in a variety of defensive behaviors, and in defensiveness to stimuli other than those on which the selection was based. © 1994 Wiley-Liss, Inc.  相似文献   
222.
Immature rats are able to give maternal care to pups and may increase their inclusive fitness by helping newborn siblings. Immature males are generally reported to be more maternal than females. In this research we studied sex differences and the extent to which they may be due to a different emotional response to novelty. We studied maternal response in two groups of immature rats of both sexes: in the naive group, juveniles aged from 18 to 30 days were given one test and showed clear-cut sex differences. The experience group was submitted to repeated tests from 18 to 30 days of age, thus eliminating the effects of novelty: as a result, all differences between sexes disappeared. A second experiment was designed in 24-day-old females to differentiate the effects of repeated handling and exposure to the test situation from that of repeated exposure to pups; moreover, the effects of an anxiety-reducing drug (diazepam) were studied. Exposure to pups is particularly efficient in facilitating maternal response. Diazepam injection was also effective, but its control showed that the injection per se was responsible for the effect. In conclusion, our results stress the importance of response to novelty and suggest that sex differences in maternal behavior of immature rats may be modulated by different emotional responses by males and females. In fact, emotionality competes with, and may exert an inhibitory effect on, the expression of a vast array of behaviors. © 1994 Wiley-Liss, Inc.  相似文献   
223.
Male mice of the C57BL/6 strain show a significant increase in aggression toward a nonaggressive male conspecific following 72 hr of individual housing. However, this increase was no longer evident following 2 weeks of individual housing. When housed with a female, C57BL/6 mice show significantly more aggression than singly housed mice of the same strain after 72 hr as well as 2, 4, 8 weeks of differential housing. Male C57BL/6 mice housed with a female also show significantly higher levels of aggression than DBA/2 mice living in the same housing condition after 4 or 8 weeks of differential housing. Finally, male DBA/2 mice individually housed for 8 weeks are significantly more aggressive than mice of the same strain housed with a female for the same time. These results indicate that the increase in aggressive behavior observed following isolation and cohabitation with a female in the mouse is not the same phenomenon. © 1994 Wiley-Liss, Inc.  相似文献   
224.
This study assessed whether two types of non-aggressive “standard opponents” (“intact” and “anosmic” group-housed males) produced similar behavioral changes in isolated OF1 male mice given several experiences of victory. Experimental groups confronted either intact or anosmic opponents every two days until they had completed four encounters. The behavioral changes were recorded using a detailed ethologically inspired analysis. These changes were clearly different depending on the opponent type. When intact opponents were used, experimental subjects increased the time spent in digging, non-social exploration, explore from a distance, and attack over encounters, but showed decreased time spent in threat and a decreased latency to the first attack. In encounters with anosmic opponents, only declines in the latencies to threat and attack were noted. Moreover, the experimental groups differed in their behaviors over encounters. Those confronting intact opponents spent less time in social investigation, more time in explore from a distance and threat, and showed a shorter latencies to threat and attack than counterparts confronting anosmics. These results suggest that, although both types of “standard opponents” are similar in their non-aggressiveness, they elicit rather different behavioral responses in their adversaries. These findings provide additional support for the view that the type of opponent used in studies on intermale aggression is of paramount importance. Indeed, the use of different types of “standardized non-aggressive opponents” appears to be an important source of variability between studies. © 1994 Wiley-Liss, Inc.  相似文献   
225.
Sanders et al.'s proposal for a management framework for conflicting interests among program developers is very welcome. The underlying principles of such a framework must nevertheless prioritise the need for researchers and commissioners of services to make objective assessments of the impact of interventions reported in journal articles. This is particularly important in the field of randomised trials which may influence public sector expenditure. Using a strict definition derived from known financial conflict of interest, we have demonstrated that child-based effect sizes are much lower for independent studies than for studies with developer involvement. On this basis, we propose that journals publishing evaluations of psychosocial interventions should agree a standardised format for declarations of conflicts of interest based on that recommended by the International Committee of Medical Journal Editors.  相似文献   
226.
Differential reinforcement is a common treatment for escape-maintained problem behavior in which compliance is reinforced on a fixed-ratio (FR) 1 schedule with brief access to positive and/or negative reinforcement. Recent research suggests some individuals prefer to complete longer work requirements culminating in prolonged (i.e. accumulated) reinforcement periods relative to brief (i.e. distributed) periods, but prolonged work exposure may evoke problem behavior and prevent compliance from contacting reinforcement when treating escape-maintained problem behavior. We exposed 3 children with escape-maintained problem behavior to both distributed (FR 1 resulting in 30 s of reinforcement) and accumulated (FR 15 resulting in 7.5 min of reinforcement) arrangements to compare their efficacy in maintaining low levels of problem behavior. We then assessed participants' preferences for these conditions in a concurrent-chains arrangement. Accumulated-reinforcement arrangements did not occasion additional problem behavior, but rather resulted in consistently lower levels of problem behavior for 2 of 3 participants. Participants demonstrated idiosyncratic preferences.  相似文献   
227.
Positive Behavior Supports for Adults with Disabilities in Employment, Community, and Residential Settings by Keith Storey and Michal Post (2019) presents valuable information for support providers and clinicians working with adults in inclusive settings who display challenging behavior. Numerous examples of challenging behavior encountered in such settings are provided along with a multitude of interventions for addressing the behavior in ways that comport with the values of positive behavior support (PBS). This review highlights contributions of the Storey and Post book and considers the content in regard to the controversial relationship between PBS and applied behavior analysis (ABA). The authors specify ABA as the foundation of PBS, but questions linger about the exact PBS–ABA relationship that will likely affect the book's ultimate contribution. Concern over the relationship is illustrated in regard to qualifications of behavioral professionals whom the authors often refer to as being necessary to help support providers develop and implement PBS interventions.  相似文献   
228.
Children diagnosed with autism spectrum disorder (ASD) often exhibit stereotypy, which can be socially stigmatizing, interfere with daily living skills, and affect skill acquisition. We compared differential reinforcement of alternative behavior (DRA) and differential reinforcement of other behavior (DRO) when neither procedure included response blocking or interruption for (a) reducing stereotypy, (b) increasing task engagement, and (c) increasing task completion. DRA contingencies yielded superior outcomes across each measure when evaluated with 3 individuals with autism spectrum disorder.  相似文献   
229.
A recent intervention, the Step it UP! game (Galbraith & Normand, 2017), consists of an interdependent group contingency to increase student physical activity. In addition, previous research demonstrated that adult interaction may reinforce physical activity (Larson et al., 2014). We extended research on the Step it UP! game by comparing the effects of no game, Step it UP! game, and Step it UP! game plus adult interaction on the number of steps taken by participants in a third-grade classroom during recess. Overall, 19 of the 25 participants took more steps during the Step it UP! game plus adult interaction compared to the Step it UP! game and no-game recesses. Furthermore, 20 participants preferred the Step it UP! game plus adult interaction. Results suggest that adult interaction can enhance the effects of the Step it UP! game to increase physical activity.  相似文献   
230.
Recently, researchers have compared the utility of isolated versus synthesized contingencies in functional analysis (FA) methodology (e.g., Fisher et al., 2016; Slaton et al., 2017). A limitation of these studies is that there were other differences across FA methodologies (e.g., design, contingency) that did not allow for isolation of the influence of isolated versus synthesized contingencies. Therefore, the current study compared outcomes of FAs that involved isolated versus synthesized contingencies for problem behavior of 5 children while controlling for these other differences across FAs (Experiment 1). Next, the current study compared the effects of interventions based on the functions identified in the isolated and synthesized contingencies for each participant (Experiment 2). Results indicated isolated contingency FAs produced differentiated responding for 1 or both functions for all 5 participants, and there were little to no differences between treatments informed by isolated and synthesized contingency FAs.  相似文献   
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