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51.
Sandra Sanchez-Roige Victor Baro Leanne Trick Yolanda Pe?a-Oliver David N Stephens Theodora Duka 《Neuropsychopharmacology》2014,39(13):2919-2927
There are well-established links between impulsivity and alcohol use in humans and animal models; however, whether exaggerated impulsivity is a premorbid risk factor or a consequence of alcohol intake remains unclear. In a first approach, human young (18–25 years) social binge and non-binge drinkers were tested for motor impulsivity and attentional abilities in a human version of the Five-Choice Serial Reaction Time Task (Sx-5CSRTT), modeled on the rodent 5CSRTT. Participants completed four variants of the Sx-5CSRT, in addition to being screened for impulsive traits (BIS-11 questionnaire) and impulsive behavior (by means of the Delay Discounting Questionnaire, Two-Choice Impulsivity Paradigm (TCIP), Stop Signal Reaction Time, and Time Estimation Task). Using a second approach, we compared one of these impulsivity measures, 5CSRTT performance, in two inbred strains of mice known to differ in alcohol intake. Compared with non-bingers (NBD; n=22), binge drinkers (BD, n=22) showed robust impairments in attention and premature responding when evaluated under increased attentional load, in addition to presenting deficits in decision making using the TCIP. The best predictors for high binge drinking score were premature responding in the Sx-5CSRTT, trait impulsivity in the BIS-11, and decision making in the TCIP. Alcohol-naïve C57BL/6J (B6) mice (alcohol preferring) were more impulsive in the 5CSRTT than DBA2/J (D2) mice (alcohol averse); the degree of impulsivity correlated with subsequent alcohol consumption. Homologous measures in animal and human studies indicate increased premature responding in young social BD and in the ethanol-preferring B6 strain of mice.Impulsivity has been consistently implicated as both a determinant and a consequence of alcohol abuse. Binge patterns of alcohol consumption, in particular, have been associated with impaired attentional function and executive function (Scaife and Duka, 2009; Townshend and Duka, 2005), and increased impulsive behavior in both humans and rodent models (Bell et al, 2013; Duka et al, 2003; Stephens and Duka, 2008). However, it is unclear whether high levels of impulsivity are a cause or consequence of alcohol intake.Given the prevalence of binge drinking in adolescence (Healey et al, 2014), the first aim of our study was to examine the relationship of binge drinking to measures of waiting impulsivity and attentional abilities in human adolescents (18–25 years old) and in rodents, which consume alcohol. Taking the rodent 5CSRTT (Robbins, 2002) as a model, we developed a novel, iPad-based task (Sussex 5CSRTT; Sx-5CSRTT), to assess both attentional performance and anticipatory behavior in humans. BD were also characterized in four additional measures of impulsivity, based on different operational definitions of the construct. The Stop Signal Task, used to assess ability to inhibit a prepotent response (Logan, 1994), served as an additional measure of ‘motoric impulsivity''. The Delay Discounting Questionnaire measured preference for immediate over-delayed rewards (Petry, 2001) and, combined with the Two-Choice Impulsivity paradigm (Dougherty et al, 2005), provided an index of ‘choice'' impulsivity or decision making; the fourth behavioral measure used was the Time Estimation Task. Although each of these five measures has been used in the clinical context as an index of impulsive behavior, the sensitivity of each task to characterize impulsive phenotype in young social BD, and their relationship to one another has not been explored. We anticipated binge drinking might be differentially associated with different aspects of impulsive behavior, but generally that high binge drinking scores would be associated with high levels of trait and behavioral motor impulsivity and aversion to delay.The role of premorbid impulsivity as a predictor of elevated alcohol intake cannot be easily disentangled in human studies, as impulsivity measures are almost inevitably assessed after a period of alcohol use. Animal models are more powerful tools in this respect as they allow the exclusion of alcohol experience as a potential contributor to impulsivity. Therefore, having established that 5CSRTT waiting impulsivity was associated with human binge drinking, we asked whether waiting impulsivity in alcohol-naïve mice predicted alcohol drinking in two widely used B6 and D2 inbred strains, that also differ in alcohol consumption (Crabbe et al, 1994). We have previously reported (Walker et al, 2011) that prior exposure to high alcohol concentrations over several weeks in adulthood has only transitory effects in increasing impulsivity in B6 mice. We predicted greater impulsivity in the high-ethanol-preferring mice indicating a potential causal relationship between waiting impulsivity and high alcohol consumption.Using homologous measures of impulsivity in mouse and humans, we provide evidence that waiting impulsivity is associated with binge drinking in young adult humans, and predicts alcohol consumption in mice. 相似文献
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Leanne Streja Catherine M. Crespi Roshan Bastani Glenn C. Wong Craig A. Jones John T. Bernert Donald Tashkin S. Katharine Hammond Barbara A. Berman 《Journal of immigrant and minority health / Center for Minority Public Health》2014,16(2):256-264
We report on the results of a low-intensity behavioral intervention to reduce second hand smoke (SHS) exposure of children with asthma from low income minority households in Los Angeles, California. In this study, 242 child/adult dyads were randomized to a behavioral intervention (video, workbook, minimal counseling) or control condition (brochure). Main outcome measures included child’s urine cotinine and parental reports of child’s hours of SHS exposure and number of household cigarettes smoked. Implementation of household bans was also considered. No differences in outcomes were detected between intervention and control groups at follow-up. Limitations included high attrition and low rates of collection of objective measures (few children with urine cotinine samples). There continues to be a need for effective culturally and linguistically appropriate strategies that support reduction of household SHS exposure among children with asthma in low income, minority households. 相似文献
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Cathleen Taylor Karen Croot Emma Power Sharon A. Savage John R. Hodges Leanne Togher 《Aphasiology》2014,28(8-9):1069-1091
Background: Primary progressive aphasia (PPA) affects a range of language domains that impact on communication. Little is known about the nature of conversation breakdown in PPA. The identification of trouble in conversation, its repair and the success of repairs has been used effectively to examine conversation breakdown in neurogenic language disorders such as dementia of the Alzheimer type (DAT) and acute onset aphasia. This study investigated trouble and repair in the conversations of people with PPA.Aims: The first aim of this study is to describe the contributions of individuals with PPA and their conversation partner to conversation. The second aim is to describe the trouble that occurs in dyadic conversations between three individuals with PPA and their communication partner. The third aim is to describe the repair behaviours used by the individuals with PPA and their communication partners.Methods & Procedures: Dyadic conversations about everyday activities between three individuals with PPA and their partners and three control dyads were video recorded and transcribed. Number of words, number of turns and length of turns were measured and trouble-indicating behaviours (TIBs) and repair behaviours were categorised.Outcomes & Results: Individuals with PPA had reduced mean length of turn but maintained their share of turn-taking. They demonstrated a variety of TIBs that differed from the noninteractive repairs, which do not require a response from the partner in the conversation and which have been observed in studies of conversation in DAT. Their partners bore the greater burden of highlighting trouble and need for repair using collaborative, interactive, TIBs. Three different conversational profiles were observed in the three PPA dyads, reflecting different patterns of language and cognitive impairment.Conclusions: Individuals with PPA were active participants in conversation effectively indicating and responding to trouble. Understanding trouble and repair in the conversations of individuals with PPA has the potential to enhance assessment and inform clinical practice. 相似文献
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