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101.
Although smoking-cessation rates have continued to increase, the vast majority of smokers who quit eventually relapse. Between 1974 and 1985, over 1.3 million smokers quit during each of those years. However, 75% to 80% of those individuals resumed smoking within six months. This article describes the dynamic phenomenon of smoking relapse within the context of cyclical episodes of smoking and quitting during an individual's lifetime. Theories of the determinants of smoking relapse are reviewed and methods designed to prevent relapse are described. Smoking relapse is discussed in terms of three aspects of tobacco addiction: (1) biological-addiction mechanisms, (2) conditioning processes, and (3) cognitive-social learning factors. The major determinants of smoking relapse are reviewed, including nicotine withdrawal, stress, weight gain, social influences, conditioning factors, causal attributions, and environmental variables. A trans-theoretical-developmental model is explored in the longitudinal investigation of the natural history of slips (lapses) and relapse episodes. Relapse prevention interventions are described that emphasize self-awareness, self-regulation, self-efficacy, affect regulation, social support, and lifestyle balance. Recent developments in pharmacological adjuncts to treatment are also examined. It is concluded that innovative relapse prevention methods need to be designed for hard-core smokers with histories of cessation failures, substance abuse and/or psychiatric impairment. These and other recommendations for future research on smoking relapse and relapse prevention are discussed.  相似文献   
102.
Rasmussen and Milner [N.Y. Acad. Sci. Vol. 299, pp. 355–379, 1977] published data on late-lesioned (after age 6) epileptic patients who had suffered left hemisphere lesions. They estimated that left hemisphere dominance occurred in 96% of dextrals and 70% of sinistrals. These figures have been regarded as valid estimates for normal dextrals and sinistrals. We administered the Bilateral Object Naming Latency Task, a verbal tachistoscopic task with very good psychometric properties, to 188 dextral and 72 sinistral normals. Results showed that 93.6% of the dextrals and 80.3% of the sinistrals were left hemisphere dominant. A consideration of results from a number of carefully conducted dichotic listening studies suggests, as do present results, that the 70% left-dominance estimate of Rasmussen and Milner for normal sinistrals may be too low by about 10%. It is suggested that ‘bilateral dominance’, present in 15% of the epileptic sinistrals of Rasmussen and Milner, may be much less common in normal sinistrals.  相似文献   
103.
Reflections and Perspectives on Pediatric Psychology: Editor's Vale Dictum   总被引:4,自引:3,他引:1  
Reviews major activities of the Editor and changes in the Journalof Pediatric Psychology (JPP) for issues published in 1993 through1997. Significant trends and accomplishments are reviewed, includingthe increased use of Special Issues and Special Sections tohighlight current pediatric psychological research. Articlespublished during the term are analyzed interms of article typeand population type Comarisons are made to earlier trends inJPP publication as reported by Roberts (1 992).  相似文献   
104.
The A-wave of the human electroretinogram and rod receptor function   总被引:6,自引:0,他引:6  
The amplitude of the leading edge of the a-wave of the human electroretinogram (ERG) was compared with predictions from a computational model of the light-induced responses of rod mammalian receptors. According to this model, a linear process describes the amplitude and time course of the response to relatively low flash intensities and at brief times after the onset of the flash. At higher flash intensities, a nonlinear process, described by the Naka-Rushton function or a saturating exponential, is involved. The primary focus here is on intensity-response data recorded with a clinical ganzfeld apparatus. The leading edge of the rod a-wave recorded from normal observers and patients with congenital stationary night blindness (CSNB) was described by a linear process for flash intensities up to the maximum available flash intensity, 2.0 log scot td-sec. This finding is consistent with the model of the rod's response. It suggests, however, that when ERGs are recorded with clinical systems limited to 2.0 log scot td-sec, these data cannot be used to distinguish between changes in the parameters (eg, semisaturation intensity versus maximum response) of the human rod receptors. Responses to flash intensities up to 3.4 log scot td-sec were recorded using a custom, high-intensity ganzfeld system. Both the linear and nonlinear components of the model were needed to fit the ERGs recorded with this system. This suggests that changes in different receptor parameters can be distinguished with higher intensity flashes.  相似文献   
105.
Stress modulation over the day in cigarette smokers   总被引:3,自引:0,他引:3  
This review summarizes the findings from a series of four published studies into the relationship between cigarette smoking and stress. In each study, feelings of anxiety/stress were significantly lower post-smoking than pre-smoking (p < 0.001). However, while moods improved immediately after smoking, mood impairments occurred between cigarettes. This repetitive cycle of mood reversals provides a clear rationale for repetitive/addictive cigarette use. The degree of stress modulation was significantly related to the sedative subscale of the Smoking Motivation Questionnaire (p < 0.01). However, high SMQ sedative subjects reported above-average stress prior to smoking, rather than below-average stress after smoking. Thus stress modulation represented mainly the relief of adverse moods, rather than the attainment of beneficial moods. Deprived smokers reported a diurnal pattern of increasing stress, confirming the deleterious effects of nicotine deprivation. These studies demonstrated the importance of mood control as a motive for smoking. They indicate that smokers gain little real advantage from cigarettes, but smoke mainly to for stall nicotine depletion. The deleterious mood effects of acute nicotine withdrawal oho helps explain why, when smokers quit smoking, they experience reduced levels of daily stress.  相似文献   
106.
Charles Ksir 《Psychopharmacology》1994,115(1-2):105-109
Nicotine has been reported to increase or decrease measures of activity in rats, including locomotor activity and rearing. Nicotine dose and repeated exposure to nicotine are known to be important factors in determining the effects on locomotor behavior. Less information has been gathered on rearing and other measures of activity. Rats were tested repeatedly, once per day, in Digiscan automated activity analyzers that reported 19 measures of activity. Each rat was given the same drug and dose each day, either saline or 0.1, 0.2, or 0.4 mg/kg nicotine. The 19 measures were combined or modified to produce 14 measures that were examined using factor analysis to help select the most independent measures. Four measures were selected to describe the effects of dose and to compare day 1 results with day 5 results. Total distance moved was increased in a dose-related fashion and was greater on day 5 than on day 1. Rearing was increased at low doses and decreased at high doses on both days. Stereotypy was increased approximately the same amount by all three doses, and was greater on day 5 than on day 1. Center time was increased by the highest dose on both days. These results once again point out the influences of repeated testing and repeated nicotine exposure on behavior. They may also help to clarify why some studies have reported that both ambulation and rearing are increased after nicotine whereas others find opposite effects.  相似文献   
107.
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools.  相似文献   
108.
The metabolic costs of rough-and-tumble play behavior were studied in juvenile rats. Using indirect calorimetry, it was determined that energy expenditure during play is increased by 66-104% over the resting metabolic rate, indicating that play accounts for between 2% and 3% of the total daily energy budget of the rat. In a subsequent experiment, food intake and body weight were monitored for 3 weeks in rats allowed to play for 1 hr/day and in rats not allowed to play. While the body weights of the two groups did not differ significantly from each other, those rats allowed to play ate 7% more over the 3-week period than did those rats not given an opportunity to play. These data are consistent with previous reports describing the energetic costs of mammalian play, with play accounting for less than 10% of the daily energy budget in three species tested so far. These data are also consistent with viewing play as a type of exercise and may lead to a better understanding of putative benefits of this behavior.  相似文献   
109.
Studies relating neuropsychology and structural neuroimaging after closed head injury are reviewed. Particular attention is given to the question of the relative contribution of focal and diffuse damage to neuropsychological impairment. The evidence currently available emphasizes the importance of diffuse damage in closed head injury. Diffuse damage is not equally distributed in the brain, and the review suggests three axes that are relevant for neuropsychological function: (1) damage may be unilateral or bilateral, (2) damage is characteristically greater in anterior regions than posterior regions, and (3) damage shows a centripetal gradient. A large gap remains between the emergent generalizations concerning head injury and reliable neuropsychological interpretation of scans from individual patients.  相似文献   
110.
The present study investigated the perception of sweetness of aspartame in comparison to various concentrations of sucrose. Twenty-seven subjects were randomly assigned to taste a chilled or room temperature Kool-Aid beverage sweetened with either aspartame or five different concentrations of sucrose. Subjects assessed the perceived similarity in sweetness of an aspartame-aspartame pair and five different aspartame-sucrose pairings and rated each beverage on five bipolar adjectives. Analysis of the similarity ratings revealed that subjects did not perceive the pairs of beverages to differ in perceived sweetness. Analysis of the adjective ratings revealed that aspartame and the lower sucrose concentrations were perceived as being less sweet and more sour than the higher sucrose concentrations.  相似文献   
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