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941.
Interactional competencies that develop in the first two years of life provide a foundation for all further social and communicative developments. Their normal acquisition, especially in the handicapped, can not be taken for granted. If delays in social-communicative development can be identified early in life and changes made in how the social environment interacts with the child, intervention may effectively facilitate social development. However, to accomplish this, both a model for describing and an instrument for assessing interactional competencies are needed. A recently developed set of scales, organized according to a cognitive-developmental framework and drawing upon recent research literature, is described in terms of its organization and content. Results that support the cognitive model underlying the set of scales are reported. The paper concludes with a consideration of potential criticisms that may apply to such a theoretically based instrument. 相似文献
942.
Fights were observed between young, unacquainted, domestic pigs. These fights were described in terms of the frequency of bites and the time spent in each of five spatial configurations of the animals. Depending on the rate that bites were given or received, each spatial configuration was characterized as resulting from offence or defence by one of the pigs. Bites were mainly directed at the head and ears, and defensive moves placed these areas out of reach. The most effective offensive move was an attack from the side. Pigs that lost fights tended to turn away from such attacks: winners were as likely to turn towards the attacker. Whether turning away is submission or simply defence is not clear. Factor analysis showed that fights could be described on three dimensions: offence by the loser along with mutual offence and mutual defence: offence by the winner and defence by the loser: and defence by the winner. Long fights involved much offence by the loser and defence by the winner: short fights involved much defence by the loser. When the pigs met again after 24 h, the fights were shorter and involved less offence and more defence by the loser. The transitions between the configurations reflect a balance of offence and defence by the pig responsible making for the transition. This balance is, in turn, affected by attacks from the opponent, fatigue, and the pig's assessment of its relative fighting ability. Retaliation against attacks is partly responsible for the persistence of fighting. 相似文献
943.
T. Berry Brazelton 《Infant mental health journal》1988,9(1):65-71
Rapid changes in family life have created enormous challenges and pressures on developing families - divorce, two working parents, disappearance of the extended family, unclear cultural values for our children's future, poorly defined support systems for stressed families, inadequate substitute care when both parents work-all contribute to an anxious atmosphere for young families. Parents who must return to work „too early”︁ (and we have no established standards yet for what this means to either child or adult development) seem to grieve about the loss of the relationship with the developing child. They may even set up defenses against making a strong and painful attachment. They may not become involved in the child's development in a way that will foster their own development as nurturing adults. The grieving and the necessary defenses against it are predictable and must be mitigated in order to foster nurturing adults within the family. Children must be provided with caring, intensely involved adults in order to assure their optimal future development. We must provide them and their parents with adequate substitute care. This paper suggests adjustments at the industrial level that must be made to foster parental involvement and to assure positive outcomes for future generations. 相似文献
944.
The marine mollusc Aplysia californica exhibits a wide range of nonassociative and associative forms of learning. Recently, we found that the learning repertoire of Aplysia includes operant conditioning (Cook & Carew, 1986, 1989b). The behavior we examined is a naturally occurring, side-to-side head-waving response used by Aplysia in seeking food, obtaining a foothold, and egg laying. Aplysia can be operantly conditioned to reduce head-waving to one side of their body if such a response results in exposure to bright uniform-field illumination, which the animals find aversive. An essential step toward achieving a mechanistic understanding of operant conditioning is to identify and characterize the reinforcement pathway used during the learning. Toward this end, we wished to determine which of the peripheral visual pathways in Aplysia are critical for performance of the operant task. Previous experiments indicated that photic input from the optic and rhinophore nerves functionally inhibited motor neurons that participate in the operant response (head-waving), while photic input from the oral veil nerves excited these same motor neurons (Cook & Carew, 1989c). These findings suggested the hypothesis that one or both of these pathways could play an important role in mediating reinforcement during training. To explore this possibility we operantly trained animals that had received chronic bilateral transections of either the optic and rhinophore nerves or the oral veil nerves C1-C3 (in conjunction with transection of the optic and rhinophore nerves). We found that operant conditioning was not disrupted by ablation of input from the eyes and rhinophores. By contrast, ablation of input from the oral veil (together with that from the eyes and rhinophores) abolished operant conditioning. Thus, the oral veil nerves play a critical modulatory role in operant conditioning of head-waving. This observation further suggested that photic input from the oral veil is conveyed to the CNS via the oral veil nerves. In a final experiment we confirmed that stimulation of the oral veil with light evokes increased afferent activity in the oral veil nerves C1-C2. These results support the idea that the oral veil nerves contain processes that are critical components of the reinforcement pathway for operant conditioning of head-waving. 相似文献
945.
Richard A. Winett Eileen S. Anderson Laurie L. Desiderato Laura J. Solomon Melissa Perry Jeffrey A. Kelly Kathleen J. Sikkema Roger A. Roffman Ann D. Norman David N. Lombard Tamara N. Lombard 《Applied and Preventive Psychology》1995,4(4):233-245
Social diffusion theory has recently been recognized as a promising approach for large-scale disease prevention and health promotion efforts. This paper describes how principles and tactics from social cognitive theory, operant psychology, social psychology, social marketing, and the overarching stages of change model can be used to further develop the conceptual and strategic (technological) bases of social diffusion theory. Within an integrative framework, we discuss in detail more effective ways to train peer mediators of behavior change as one example of how social diffusion theory can benefit from this conceptual and strategic reformulation. We then further illustrate the use of peer mediators of change in human immunodeficiency virus (HIV) and cancer prevention intervention studies with both interventions training peer mediators to diffuse information, norms, and risk reduction strategies. Although the results of these studies showed reductions in high-risk behaviors across population segments, more closely following the framework discussed in this article should further increase the behavior change potential of future interventions based on social diffusion theory. 相似文献
946.
M Peder T Porkka-Heiskanen A Alila M L Laakso G Johansson 《Behavioral and neural biology》1989,51(2):237-246
Recently nighttime melatonin levels have been shown to be attenuated in depressive patients or patients with dementia of the Alzheimer type. On the other hand, depression can be transiently relieved by deprivation of rapid eye movement sleep. Since exogenous melatonin administration increases rapid eye movement sleep and slow wave sleep in the rat, could rapid eye movement sleep deprivation then inversely influence endogenous melatonin production? We found indices that in castrated Wistar rats 4 days of rapid eye movement sleep deprivation by the cuff pedestal method elevates the pineal content of melatonin by a factor of two at 1 to 2 h after light onset. Rapid eye movement sleep is thus suggested to influence pineal activity. This mechanism might be involved in the human depression-alleviating effect of rapid eye movement sleep deprivation. 相似文献
947.
A recent study of the development of nonassociative learning in the siphon withdrawal reflex of Aplysia showed that dishabituation (facilitation of an habituated response) and sensitization (facilitation of a nonhabituated response) emerge according to different developmental timetables: dishabituation precedes sensitization by approximately 60 days (Rankin & Carew, 1988). Both forms of facilitation of the reflex were observed within 90 s of an electrical shock to the tail. However, more recent work by Marcus and colleagues (1988) in adult animals revealed that sensitization can have a delayed onset of 20-30 min after a strong tail shock. Since the developmental study of Rankin and Carew (1988) only tested the reflex for 10 min after tail shock, it is possible that sensitization was in fact present at earlier developmental stages, but was undetected. To examine this question, in the present study we utilized a longer (40-50 min) post-shock observation period to determine whether delayed-onset sensitization is exhibited in juvenile Aplysia, and if so, when it is expressed during development. In our first experiment, we found that Early Stage 12 juveniles (80-95 days after metamorphosis) showed significant delayed-onset sensitization 30-50 min after a strong tail shock. In a second experiment, we found that delayed-onset sensitization was absent in Stage 11 animals (20-70 days after metamorphosis). Thus delayed-onset sensitization emerges in Early Stage 12. The fact that the birthdate of delayed-onset sensitization is at least 30 days after that of dishabituation (Rankin & Carew, 1987, 1988) supports the hypothesis that these two forms of nonassociative learning may have at least partly different underlying mechanisms. 相似文献
948.
Male Sprague-Dawley rats, trained to perform a delayed-non-match-to-sample eight-arm radial maze task, were implanted with a single cannula aimed at the medial septal nucleus. A within-subjects design was utilized to examine the effects of intraseptal administration of bicuculline (0.5 micrograms) on performance of this task with 1- and 4-h delay intervals imposed between choices four and five. Administration of bicuculline immediately following the first four choices produced an impairment in maze performance at both a 1- and a 4-h delay interval. This treatment also produced an increase in latency per choice. Bicuculline-induced impairments were not observed when administered 2 h following the predelay session (2 h prior to testing). These data support previous observations that pharmacological manipulation of GABAergic activity within the septum modifies working memory processes. 相似文献
949.
C A Netto J T Valente J B Borges-Sobrinho J Lasevitz C A Tomaz 《Behavioral and neural biology》1991,55(1):114-122
Rats were exposed to an open field with flashing light (OFL; 60-W lamp, 30 Hz, for 7 min) 2 h after training and/or 2 h before testing in a two-way active avoidance task (30 trials, 0.5-mA footshock). Post-training OFL presentation caused retroactive interference, i.e., a retrieval impairment/amnesia for the avoidance task. Pretest OFL exposure reversed the post-training OFL-induced retrieval deficit. Diazepam (2.0 mg/kg), atropine (2.0 mg/kg), and methylatropine (0.1 mg/kg) administered before post-training OFL presentation blocked the OFL amnesic effect. However, these drugs did not counteract the pretest OFL-induced recovery of retrieval. Atropine and methylatropine administered 2 h before testing to rats receiving only post-training OFL presentation canceled the OFL-interfering effect. These results suggest: (1) that the amnesic effect of post-training OFL is due to failure of retrieval of the avoidance task, (2) that the reversal of this retrieval impairment by pretest OFL exposure may involve either priming or state-dependent mechanisms, and (3) that there are different modulatory mechanisms involved in post-training and pretest OFL effects. 相似文献
950.
Sex Roles - Essentialism, or the belief that certain categories have fundamental, intrinsic, and stable essences, pervasively influences social judgments. Among the many groupings that describe... 相似文献