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151.
Intrinsic sensitization is a form of behavioral facilitation that is distinct from the extrinsic sensitization normally studied. To examine whether intrinsic and extrinsic sensitization are mediated by different physiological processes, the effects of 5,7-dihydroxytryptamine-induced serotonin (5-HT) depletion on intrinsic sensitization of the leech whole-body shortening response were observed. Previous experiments have shown that 5-HT depletion disrupts dishabituation and extrinsic sensitization of this behavior in the leech. Intrinsic sensitization was observed in preparations from both control and 5-HT-depleted animals, indicating that this form of behavioral facilitation was not affected by 5-HT depletion. The differences in the effects of 5-HT depletion on intrinsic versus extrinsic sensitization suggest that there are distinct neurophysiological processes mediating these two forms of behavioral facilitation. In addition, 5-HT depletion appeared to disrupt a putative extrinsic form of habituation of the shortening reflex. These data support the hypothesis that both intrinsic and extrinsic processes of neuromodulation mediate habituation and sensitization. 相似文献
152.
Anxiety Symptomatology in Mexican-American Adolescents 总被引:3,自引:0,他引:3
Saundra H. Glover Andres J. Pumariega Charles E. Holzer III Brian K. Wise Moises Rodriguez 《Journal of child and family studies》1999,8(1):47-57
Mexican-American adults and adolescents in general have been reported to have high levels of anxiety symptomatology. In our study of a tri-ethnic sample of 2528 junior and senior high school students, the Youth Self Report (YSR) version of the Child Behavior Checklist (CBCL) and a sociodemographic questionnaire was used to assess the anxiety symptoms of Hispanic youth. We compared the ratings on anxiety symptoms, using Achenbach's anxiety subscale on the YSR, between two populations. The anxiety levels of youth in coastal southeast Texas (Galveston County) were compared to the anxiety levels of youth in the lower Rio Grande Valley. We found that Mexican-Americans of the Lower Rio Grande Valley scored higher on anxiety symptoms than the tri-ethnic population of Galveston County. Other factors associated with higher anxiety scores for Mexican-American youths included being born outside the US, linguistic fluency, father absent from the home, mother's education, and household size. Multiple regression analyses showed that socio-economic status (SES), family composition, and linguistic fluency had a greater relative impact on anxiety symptomatology than all other factors, both for the total sample as well as for the Mexican-American sample. These results parallel previous findings, with Mexican-American adults, which suggest either higher risk for anxiety symptomatology or a culturally related bias in the reporting of such symptoms. 相似文献
153.
One of the main functions of categories is to allow inferences about new objects. However, most objects are cross-classified, and it is not known whether and how people combine information from these different categories in making inferences. In six experiments, food categories, which are strongly crossclassified (e.g., a bagel is both a bread and a breakfast food), were studied. For each food, the subjects were told fictitious facts (e.g., 75% of breads are subject to spoilage from Aspergillus molds) about two of the categories to which it belonged and then were asked to make an inference about the food (e.g., how likely is a bagel to be subject to spoilage from Aspergillus molds?). We found no more use of multiple categories in these cases of cross-classification than in ambiguous classification, in which it is uncertain to which category an item belongs. However, some procedural manipulations did markedly increase the use of both categories in inferences, primarily those that focused the subjects’ attention on the critical feature in both categories. 相似文献
154.
Steve Sussman Thomas R. Simon Alan W. Stacy Clyde W. Dent Anamara Ritt Michele D. Kipke Susanne B. Montgomery Dee Burton Brian R. Flay 《Journal of applied social psychology》1999,29(8):1555-1581
This study provides a cross-sectional analysis of the relations between group self-identification and adolescent drug use in 3 samples of youth: comprehensive high-school, continuation high-school, and runaway/street youth. Youth identified with discrete groups in all 3 samples, and similar general groups were formed. In most comparisons, a high-risk group showed greater levels of drug use than did other groups. This is the first study to demonstrate that group self-identification (a) is a generalizable construct across different types of adolescent samples, (b) is related to use of drugs other than tobacco, and (c) remains a significant correlate of drug use controlling for its relations with demographic variables and several other psychosocial variables. 相似文献
155.
Omega (n)-3 and n-6 fatty acids are important membrane components of neurons and immune cells, and related to psychiatric and inflammatory diseases. Increased ratio of n-6/n-3 in the blood has been reported in depressed patients and in students following stress exposure. The n-3 fatty acid, eicosapentaenoic acid (ethyl-EPA) suppresses inflammation and has antidepressant properties. Interleukin (IL)-1beta can stimulate corticosterone secretion, induce anxiety and stress-like behavior and inflammatory responses. This study was to evaluate the effect of diets enriched with coconut oil, ethyl-EPA and soybean oil on central IL-1beta induced stress and anxiety-like behavior, induced changes in the concentration of prostaglandin (PG) E2 and corticosterone and the release of IL-10. Groups of rats were fed with either 5% coconut oil (as control diet), 0.2% EPA with 4.8% coconut oil or 1% EPA with 4% coconut oil and 5% soybean oil for 7 weeks. The central administration of IL-1beta induced sickness, stress and anxiety-like behavior as indicated by a reduction in body weight, decreased time spent, and the number of entries, into the open arms of the elevated plus maze and decreased exploration and entry into the central zone of the "open field" apparatus. IL-1beta also increased PGE2 and corticosterone concentrations and decreased the release of IL-10 from leucocytes. Food enriched with ethyl-EPA but not soybean oil, significantly attenuated most of these changes. These results demonstrate that ethyl-EPA has anti-inflammatory, anti-stress and anti-anxiety effects in rats. 相似文献
156.
Kevin D. McCaul Amy B. Mullens Kathleen M. Romanek Shannon C. Erickson Brian J. Gatheridge 《Cognition & emotion》2013,27(8):1780-1798
We tested a strategy to encourage cigarette smokers to think more frequently about the negative consequences of smoking, reasoning that increased thought might lead to greater worry and motivation to quit. College students who smoked daily were randomly assigned to one of three conditions in which they wore watches for one week that sounded an alarm randomly four times each day. When alerted, the students read one of eight cards that either had a written statement about studying (control condition), a statement about the negative effects of smoking behaviour (text condition), or a negative smoking statement accompanied by a picture (e.g., a blackened lung; image condition). Measures collected at week's end revealed that the smoking cards had no effects on perceived risk, but they increased worry and reports of intrusive thoughts, and had a small but reliable effect on plans to quit. Correlational data also supported the relationship between worry and motivation to quit, and we discuss the possible benefits of “normal” worrying and strategies for capitalising on the worry–motivation relationship to encourage smokers to abandon cigarettes. 相似文献
157.
McKenzie K. Roddy Kayla Knopp Emily Georgia Salivar Brian D. Doss 《Family process》2021,60(1):102-118
Initial evidence suggests that gains in relationship functioning from brief, web‐based programs are maintained through one year following the intervention; however, whether these results generalize to a low‐income sample is unclear. Furthermore, previous research from in‐person couple therapy suggests there may be different shapes of maintenance slopes for behavioral versus acceptance‐based techniques. This study contacted 668 individuals who enrolled in online behavioral (ePREP) or acceptance‐based (OurRelationship) programs one year following completion of the program. Multilevel modeling was used to examine linear and quadratic rates of change in the year following the online intervention as well as total amount of change from pretreatment to 12‐month follow‐up for both relationship and individual functioning. The majority of couples who responded continued to be in a relationship with the same partner (68.3%). Examinations of relationship functioning indicated couples in both programs maintained their gains over follow‐up (i.e., no significant linear or quadratic changes), with medium‐to‐large within‐group effect sizes from pre‐ to one‐year follow‐up. There were no significant differences in relationship outcomes between OurRelationship and ePREP. Similarly, examinations of individual functioning outcomes indicated couples maintained their gains over follow‐up or continued to improve. In total, couples experienced small‐to‐medium within‐group effect sizes from pretreatment to one‐year follow‐up, with larger effects for individuals who were initially distressed. These results suggest that online programs create lasting change for low‐income couples in relationship and individual functioning, with minimal differences between behavioral and acceptance‐based orientations. 相似文献
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