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201.
The effects of flavor preexposure and test interval on conditioned taste aversions were examined in four experiments. In the first three experiments, prior experience with a flavor different from that used as a conditioned-stimulus (CS) produced attenuated aversions when testing occurred after a 1-day interval but not after a 21-day interval. Preexposure to the same stimulus used as a CS produced attenuated aversions at both 1- and 21-day intervals. In Experiment 4, a delay interval between flavor preexposure and conditioning eliminated the attenuating effect of preexposure, but only when different stimuli were used for preexposure and conditioning. These data could not be easily accounted for by contemporary interpretations of preexposure as an event that interferes with subsequent acquisition of a conditioned aversion. An alternative retrieval interference hypothesis was outlined. 相似文献
202.
In two experiments, we assessed the ability of a feedback stimulus during helplessness training to reduce the performance deficits common to inescapable shock. In each experiment, four groups of rats were exposed to either escapable shock (E), inescapable shock with a feedback stimulus following shock termination (Y-FS), inescapable shock with no feedback stimulus (Y-NFS), or no shock (N). The feedback stimulus eliminated the interference effects of inescapable shock when tested with an FR-3 lever press escape task (Experiment 1) or on an FR-1 task with a 3-s delay between the response and shock termination (Experiment 2). These results suggest that stress-induced biochemical changes may mediate the interference effects seen in inescapably shocked rats. 相似文献
203.
Three experiments investigating the effects of arousal on the T-maze choice behavior of inbred mouse strains are reported. In Experiment 1, CBA and NZB mice were administered unrewarded free choice alternation tests on 10 consecutive days under either No Shock, Shock Start (shocked in the start box), or Shock Choice (shocked at the choice point) treatment conditions. Both strain and treatment effects were observed: In the No-Shock condition, the nonreactive CBA strain alternated, but the reactive NZB strain did not. In the Shock Start condition the CBA strain showed only a suppressed alternation, while the NZB strain administered the same treatment perseverated. Both strains perseverated in the Shock Choice condition. In Experiment 2, NZB mice administered identical shocks in the start box and goal arms on both trials of five consecutive tests conducted once a day perseverated to the same goal arm in which they had been shocked on the first trial. In Experiment 3, NZB mice punished for perseverating (with shock continuation) and simultaneously reinforced for alternating (with shock termination) showed a “punishment paradox”; they perseverated despite the reinforcement contingencies. These results, which are congruent with the optimal arousal theory and several characteristics the theory shares with the emergent neophobia construct, support the contention that arousal mediates a symmetrical relationship between approach and avoidance along a novelty-familiarity continuum. 相似文献
204.
Edward J Callen Wallace R McAllister Dorothy E McAllister 《Learning and motivation》1984,15(3):302-320
In two experiments, fear was conditioned to the situational cues in one compartment of a hurdle-jumping apparatus and was then extinguished. Subsequently, either one shock (Experiment 1) or three or nine shocks (Experiment 2) were given in a situation distinctively different from that in which conditioning and extinction had taken place. Although some associative strength between the situational cues and fear was shown to have remained after extinction, in neither experiment did the postextinction-shock treatment increase the fear elicited by these cues: Escape-from-fear performance was no better in the shocked groups than in control groups given no additional shock. Thus, the nonassociative hypothesis which postulates that inflating the value of the representation of the UCS with shock-alone presentations can reinstate the extinguished fear of a stimulus was not supported. Rather, the results showed that, after extinction, an increase in fear of a simulus depended on further conditioning to that stimulus. The data also indicated that the nonvisual components of the situational cues predominated over the visual component. 相似文献
205.
To evaluate a contingency interpretation of conditioned inhibition (CI), rats were given “explicity unpaired” training in which the locus and duration of a CS within the inter-US (shock) interval were systematically manipulated for different groups. Summation and retardation tests in Experiment 1 indicated that stronger CI resulted from both a backward and a trace CS than from a midlocus CS of equal or greater duration. Complementing these findings, the same tests in Experiment 2 showed that, by comparison with novel-stimulus controls, CI developed to a trace CS but not to a mid-locus CS, nor to a trace CS that was accompanied by an immediate signal for the US. These findings argue against a contingency interpretation of CI and favor a contiguity interpretation stressing the short-term rehearsal of stimulus events. Such rehearsal of the US allows a backward CS, but not a mid-locus CS with an extended US-CS interval, to be discriminated as a signal for nonreinforcement, and thus to develop as a conditioned inhibitor. Similarly, excitatory conditioning to the memory trace of a CS allows the nominal trace CS to develop as a signal for nonreinforcement, and thus as a conditioned inhibitor, but not when its memory trace is overshadowed by another CS that immediately precedes the US. In short, the development of CI is facilitated when excitation is mediated by the memorial processing of either the US or a discrete CS for the US rather than by contextual cues. 相似文献
206.
Emily J. Charvat Chelsea L. Garneau-Rosner James Kale Monk Colleen W. Colaner 《Family process》2023,62(1):423-441
This study extends prior research on the intergenerational transmission of relationship instability by examining parents' history of on-off relationships as a predictor of emerging adults' own cycling (i.e., breaking up and renewing with the same romantic partner). Data were collected at a large mid-western university from 702 emerging adults (18–25 years old). Multinomial logistic regression was used to predict the likelihood that participants had cycled in a past or current relationship. Results show that parental cycling increased the likelihood of offspring cycling in a past or current relationship relative to never cycling, and greater uncertainty about the future of the relationship was a mechanism through which such transmission occurred. Findings from this study demonstrate that parental relationship instability can even be consequential for the transient relationships within emerging adulthood, making family history a productive area to explore for practitioners working with cyclical partners and/or emerging adults. 相似文献
207.
Philip Nielsen Henk Rigter Niels Weber Nicolas Favez Howard A. Liddle 《Family process》2023,62(1):108-123
For some adolescent gamers, playing online games may become problematic, impairing functioning in personal, family, and other life domains. Parental and family factors are known to influence the odds that adolescents may develop problematic gaming (PG), negative parenting and conflictual family dynamics increasing the risk, whereas positive parenting and developmentally supportive family dynamics protecting against PG. This suggests that a treatment for adolescent PG should not only address the gaming behaviors and personal characteristics of the youth, but also the parental and family domains. An established research-supported treatment meeting these requirements is multidimensional family therapy (MDFT), which we adapted for use as adolescent PG treatment. We report here on one adaptation, applying in-session gaming. In-session demonstration of the “problem behavior” is feasible and informative in PG. In the opening stage of therapy, we use in-session gaming to establish an alliance between the therapist and the youth. By inviting them to play games, the therapist demonstrates that they are taken seriously, thus boosting treatment motivation. Later in treatment, gaming is introduced in family sessions, offering useful opportunities to intervene in family members' perspectives and interactional patterns revealed in vivo as the youth plays the game. These sessions can trigger strong emotions and reactions from the parents and youth and give rise to maladaptive transactions between the family members, thus offering ways to facilitate new discussions and experiences of each other. The insights gained from the game demonstration sessions aid the therapeutic process, more so than mere discussion about gaming. 相似文献
208.
Dietrich Werner 《The Ecumenical review》2023,75(1):16-32
This article offers an overview of the 11th Assembly of the World Council of Churches, which met in Karlsruhe, Germany, in August–September 2022. It sets out the context in which the assembly took place, the main issues discussed, and perspectives for the future. The article argues that the assembly in Karlsruhe demonstrated that the ecumenical movement still is alive and can offer enormous potential in a world at the brink of a new East–West divide, facing a significant weakening of multilateral structures of cooperation, and even the threat of nuclear war. Moreover, the Karlsruhe assembly demonstrated that on subjects such as the Middle East, peace ethics, and nationalism, and in the deep commitment and spiritual life of its participants, the ecumenical movement is vital and vibrant and represents a countercultural force against rigid nationalisms. 相似文献
209.
Pope Francis 《The Ecumenical review》2023,75(1):69-70
This is the text of the message of greetings of His Holiness Pope Francis to the 11th Assembly of the World Council of Churches, meeting in Karlsruhe, Germany, from 21 August to 8 September 2022. 相似文献
210.
Ann Jacob 《The Ecumenical review》2023,75(1):82-83
This is the text of the youth testimony at the opening prayer of the 11th Assembly of the World Council of Churches on 31 August 2022. 相似文献