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811.
The role of noradrenaline in learned behaviors: studies using DSP4   总被引:1,自引:0,他引:1  
DSP4 (N-2-chloroethyl-N-ethyl-2-bromobenzylamine) is a novel noradrenaline (NA) neurotoxin sufficiently selective, following systemic administration, to be a pharmacological tool of much potential; this possibility has warranted the extensive use of DSP4 to study the role of noradrenaline in learned behaviors. Thus, after DSP4 treatment (50 mg/kg) a very robust two-way active avoidance impairment is incurred and this deficit remained over a wide range of stimulus conditions and parameters. On the other hand, the acquisition of relatively simple tasks such as one-way active avoidance, fear conditioning, step-down passive avoidance and taste-aversion conditioning, was only slightly affected or not affected at all. DSP4 administration caused a retardation of the rate of acquisition of a "right-turn" running response for food reward in a modified T-maze, and an attenuation of the exteroceptive context effect in taste-aversion conditioning and extinction. In spite of a few similar results, NA-depletions following DSP4 generally do not produce the same behavioral effects as the 6-Hydroxydopamine lesions but are more akin to the locus coeruleus lesion. An hypothesis of the role of central NA, based mainly upon the shuttle box procedure, incorporates a function in establishing the Signal-Response association, in adapting to situations that require a correct response to stress and in maintaining an adequate span of attention to the range of environmental events presented in any given learning situation.  相似文献   
812.
Two experiments examined the relations among self-esteem, perceived competency to cope, and actual coping behaviors following a threat communication. Leventhal's “parallel response model” (in Advances in experimental social psychology, L. Berkowitz (Ed.), New York: Academic Press, 1970, Vol. 5) predicts that low-esteem subjects will show deficits in both competency and coping behaviors. Experiment 1 manipulated threat level of a tetanus communication. Low-esteem subjects showed coping deficits on measures of free associations, free recall, fatalism, and coping. Threat groups differed only on fear and danger measures. Experiment 2 manipulated the fear level of an antismoking film and used false feedback to alter perceived competency. Positive feedback increased perceived competency to quit smoking among low-esteem subjects only. Without feedback, low-esteem subjects reduced smoking less than high-esteem subjects; positive feedback reversed the pattern. The discussion argued that, consistent with Leventhal's model, the low-esteem coping deficit has two independent causes: (1) excessive concern with fear, and (2) inadequate perceived competency.  相似文献   
813.
Two experiments examined alternative explanations for the Scheier and Carver(1977) results linking self-focused attention to increased responsivity to emotional stimuli. In both studies autonomic, expressive, and self-report measures of emotional arousal failed to confirm the earlier findings. An individual difference measure reported by others to parallel the effects of situationally manipulated self-attention also failed to confirm the previously reported findings. Though in direct contradiction to Scheier and Carver's results, the results are consistent with a facial feedback hypothesis and with previous findings on the effects of expressive inhibition on self-reports of emotional arousal.This research was supported in part by NSF grant 77-08926 to the first author and by NIMH grant MH 29446 to the third author, as well as by funds from the Lincoln Filene Endowment to Dartmouth College.  相似文献   
814.
815.
816.
What career decision-making procedures enable people to make decisions that yield consequences congruent with their own values? The 40 “best” (most congruent) and 40 “worst” decision makers on the Career Decision Simulation were compared in a sample of 148 community college students. No significant differences appeared in the amount of double checking, number of occupations and information sources checked, amount of information collected, decision time required, and the proportion of information sought about high values. The “best” decision makers, however, were significantly more persistent in immediately seeking more information about an occupation that seemed to match one of their most important personal work values. Following a values-guided search appears more effective than simply searching exhaustively.  相似文献   
817.
The major components of Dry-Bed Training (DBT) (Azrin et al., 1974), in addition to the urine-alarm device, were identified as; (i) the waking schedule; (ii) retention control training; and (iii) positive practice and cleanliness training. Combinations of these components yielded six treatment groups. Together with an alarm-only group and a DBT group from a previous study (Bollard and Nettelbeck, 1981) these groups were compared for effectiveness in arresting bedwetting. Bedwetting frequency was reduced slightly below levels achieved with alarm-only treatment, by the addition of either retention control training, or positive practice and cleanliness training. A more substantial decrease in bedwetting resulted from the addition of the waking schedule, although none of the effects of the single components was statistically significant. The effects of the three components were cumulative, so that the more components added to the alarm-only procedure, the better the therapeutic response. Thus, the combination of waking, positive practice and cleanliness training with the alarm and the combination of all three components with the alarm (i.e. the complete DBT programme) did result in a significant reduction in bedwetting frequency compared with the alarm-only procedure. The practical and theoretical implications of these results are discussed.  相似文献   
818.
Twenty hospitalized alcoholics served as their own controls in a study which sought to compare psychophysiological and cognitive factors as mediating influences on the priming effect of alcohol. Ten subjects were independently assessed by a psychiatrist as being severely dependent on alcohol and ten as mildly or moderately alcohol dependent. Physiological, behavioural and subjective indices of the motivation to drink alcohol were employed 15 and 60 min after subjects had consumed beverages on four separate occasions corresponding to four priming conditions. These priming drinks contained either 60 ml vodka in heavy dilution or just tonic water, and in each of these conditions subjects were either led to believe that the beverages contained alcohol or they had no alcohol. The severely-dependent group displayed a degree of concordance between the indices of motivation to drink, and the levels of these tended to be significantly higher than in the less-dependent subjects. The results suggest that severely alcohol-dependent subjects were more disposed to drink 60 min after consuming alcoholic drinks than after soft drinks, regardless of whether they believed that the priming drinks had contained alcohol. Cognitive factors assumed greater importance for the drinking behaviour of less-dependent subjects, although there was evidence of discordance across behavioural, physiological and subjective measures for this group.  相似文献   
819.
820.
Two studies were conducted in all-electric townhouses and apartments in the winter (N = 83) and summer (N = 54) to ascertain how energy conservation strategies focusing on thermostat change and set-backs and other low-cost/no-cost approaches would affect overall electricity use and electricity used for heating and cooling, the home thermal environment, the perceived comfort of participants, and clothing that was worn. The studies assessed the effectiveness of videotape modeling programs that demonstrated these conservation strategies when used alone or combined with daily feedback on electricity use. In the winter, the results indicated that videotape modeling and/or feedback were effective relative to baseline and to a control group in reducing overall electricity use by about 15% and electricity used for heating by about 25%. Hygrothermographs, which accurately and continuously recorded temperature and humidity in the homes, indicated that participants were able to live with no reported loss in comfort and no change in attire at a mean temperature of about 62 degrees F when home and about 59 degrees F when asleep. The results were highly discrepant with prior laboratory studies indicating comfort at 75 degrees F with the insulation value of the clothing worn by participants in this study. In the summer, a combination of strategies designed to keep a home cool with minimal or no air conditioning, in conjunction with videotape modeling and/or daily feedback, resulted in overall electricity reductions of about 15% with reductions on electricity for cooling of about 34%, but with feedback, and feedback and modeling more effective than modeling alone. Despite these electricity savings, hygrothermograph recordings indicated minimal temperature change in the homes, with no change in perceived comfort or clothing worn. The results are discussed in terms of discrepancies with laboratory studies, optimal combinations of video-media and personal contact to promote behavior change, and energy policies that may be mislabeled as sacrificial and underestimate the effectiveness of conservation strategies such as those investigated in these studies.  相似文献   
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