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941.
Children with autism spectrum disorder (ASD) who have limited speech are often taught to communicate using a speech-generating device (SGD). We evaluated procedures for teaching a mand for information (i.e., Where is [item]?) using an interrupted behavior chain procedure. In Experiment 1, all participants (3 children with ASD who communicated using an SGD) acquired the target mand but transfer to a novel stimulus did not occur. In the second experiment, 2 participants were taught to approach alternative communication partners when the first partner did not provide the information. The second experiment also included procedures to test whether the responses were under the control of appropriate motivating operations (MOs). Generalization across communication partners occurred with both participants, but transfer across behavior chains with only 1 participant. The results of both experiments suggest that teaching multiple behavior chains and evaluating MO control may be necessary to establish generalized manding for information.  相似文献   
942.
Children diagnosed with autism spectrum disorder are often more selective in their food preferences than their typically developing peers. Additionally, many preferred food selections have minimal nutritional value. We evaluated the preference for, and reinforcing efficacy of, fruits and vegetables compared with salty and sweet foods, which are often used as edible reinforcers. Multiple-stimulus preference assessments were conducted to identify preferred foods, and reinforcer assessments were conducted to determine the reinforcing efficacy of more preferred foods. Fruits and vegetables were sometimes preferred over salty or sweet foods and often functioned as reinforcers. Future research should incorporate fruits and vegetables into preference assessments when identifying putative reinforcers.  相似文献   
943.
Habit reversal training (HRT) has been a mainstay of behavior analysts' repertoire for nearly the last 50 years. HRT has been effective in treating a host of repetitive behavior problems. In the face of the current coronavirus pandemic, HRT has practical public health importance as a possible intervention for reducing hand-to-head behaviors that increase the risk of viral infection. The current paper provides a brief review of HRT for hand-to-head habits that is designed for a broad audience and concludes with practical suggestions, based on HRT, for reducing face-touching behaviors.  相似文献   
944.
Lee  Sangil  Glaze  Chris M.  Bradlow  Eric T.  Kable  Joseph W. 《Psychometrika》2020,85(3):716-737
Psychometrika - In intertemporal and risky choice decisions, parametric utility models are widely used for predicting choice and measuring individuals’ impulsivity and risk aversion. However,...  相似文献   
945.
Five male/two female rat colonies were established in visible burrow systems, with males selected for pregrouping attack scores and also evaluated in open field and cat odor tests. Dominant-subordinate pregrouping attack differences suggested that the males becoming dominant are those showing more persistent and higher level attack. For six colonies showing dominant-subordinate behavioral differences, pregrouping defense tests failed to predict subordinate status. However, pregrouping defense scores were reliably correlated with subordinate pre-postgrouping change scores for voluntary ethanol consumption. Subordinates showed higher ranked ethanol consumption than dominants, but these groups were not different on pregrouping ethanol consumption. Subordinate postgrouping ethanol consumption was positively correlated with pregrouping attack toward an adult intruder, consonant with previous findings that highly aggressive subordinates are the targets of more intense attack by dominants. These results provide further support for a view that subordination stress increases voluntary ethanol consumption in male rats and suggest some additional individual differences factors that may be involved in increased ethanol consumption for male subordinates. © 1992 Wiley-Liss, Inc.  相似文献   
946.
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   
947.
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   
948.
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   
949.
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   
950.
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   
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