Home About us Contact | |||
Individual Vulnerability (individual + vulnerability)
Selected AbstractsIndividual vulnerability to escalated aggressive behavior by a low dose of alcohol: decreased serotonin receptor mRNA in the prefrontal cortex of male miceGENES, BRAIN AND BEHAVIOR, Issue 1 2010S. Chiavegatto Low to moderate doses of alcohol consumption induce heightened aggressive behavior in some, but not all individuals. Individual vulnerability for this nonadaptive behavior may be determined by an interaction of genetic and environmental factors with the sensitivity of alcohol's effects on brain and behavior. We used a previously established protocol for alcohol oral self-administration and characterized alcohol-heightened aggressive (AHA) mice as compared with alcohol non-heightened (ANA) counterparts. A week later, we quantified mRNA steady state levels of several candidate genes in the serotonin [5-hydroxytryptamine (5-HT)] system in different brain areas. We report a regionally selective and significant reduction of all 5-HT receptor subtype transcripts, except for 5-HT3, in the prefrontal cortex of AHA mice. Comparable gene expression profile was previously observed in aggressive mice induced by social isolation or by an anabolic androgenic steroid. Additional change in the 5-HT1B receptor transcripts was seen in the amygdala and hypothalamus of AHA mice. In both these areas, 5-HT1B mRNA was elevated when compared with ANA mice. In the hypothalamus, AHA mice also showed increased transcripts for 5-HT2A receptor. In the midbrain, 5-HT synthetic enzyme, 5-HT transporter and 5-HT receptors mRNA levels were similar between groups. Our results emphasize a role for postsynaptic over presynaptic 5-HT receptors in mice which showed escalated aggression after the consumption of a moderate dose of alcohol. This gene expression profile of 5-HT neurotransmission components in the brain of mice may suggest a vulnerability trait for alcohol-heightened aggression. [source] REVIEW: Stress, alcohol and drug interaction: an update of human researchADDICTION BIOLOGY, Issue 1 2009Magdalena Uhart ABSTRACT A challenging question that continues unanswered in the field of addiction is why some individuals are more vulnerable to substance use disorders than others. Numerous risk factors for alcohol and other drugs of abuse, including exposure to various forms of stress, have been identified in clinical studies. However, the neurobiological mechanisms that underlie this relationship remain unclear. Critical neurotransmitters, hormones and neurobiological sites have been recognized, which may provide the substrates that convey individual differences in vulnerability to addiction. With the advent of more sophisticated measures of brain function in humans, such as functional imaging technology, the mechanisms and neural pathways involved in the interactions between drugs of abuse, the mesocorticolimbic dopamine system and stress systems are beginning to be characterized. This review provides a neuroadaptive perspective regarding the role of the hormonal and brain stress systems in drug addiction with a focus on the changes that occur during the transition from occasional drug use to drug dependence. We also review factors that contribute to different levels of hormonal/brain stress activation, which has implications for understanding individual vulnerability to drug dependence. Ultimately, these efforts may improve our chances of designing treatment strategies that target addiction at the core of the disorder. [source] Behavioral Consequences of Repeated Nicotine During Adolescence in Alcohol-Preferring AA and Alcohol-Avoiding ANA RatsALCOHOLISM, Issue 2 2009Heidi Kemppainen Background:, Epidemiological studies suggest that exposure to nicotine at adolescent age is associated with increased potential to use alcohol and that genetic predisposition may further increase the risk. The present study addressed adolescent vulnerability to repeated nicotine exposure and its influence on subsequent ethanol self-administration by investigating interactions between nicotine-induced behavioral sensitization and voluntary ethanol consumption in alcohol preferring AA (Alko Alcohol) and alcohol nonpreferring ANA (Alko Non-Alcohol) rat lines selected for differential ethanol intake. Methods:, Adolescent and adult rats received 10 injections of nicotine (0.5 mg/kg s.c.), given every second day from postnatal day (Pnd) 27 and 75, respectively. Nicotine-induced (0.5 mg/kg) locomotor activity was measured acutely after the first injection, and after the repeated treatment with nicotine on Pnds 52 and 86 in the adolescent groups and on Pnd 99 in the adult groups. After this, acquisition of voluntary ethanol (10% v/v) consumption as well as nicotine-induced (0.5 mg/kg) ethanol intake was measured in the AA rats. Results:, Adolescent AA rats were more sensitive than adolescent ANA rats to the locomotor effects of nicotine. They were also stimulated more than adult AA rats, but such a difference was not found among ANA rats. Adolescent and adult rats did not differ in their susceptibility to nicotine-induced behavioral sensitization. Genetic predisposition to ethanol self-administration did not interact with development of behavioral sensitization in either adolescents or adults. Acquisition of ethanol intake was enhanced in the adolescent groups relative to the adult groups in a manner that was independent of the nicotine treatment. An increase in ethanol intake was found after challenging animals with nicotine, and this effect was enhanced in the nicotine-treated adolescent group. Conclusions:, These findings provide no or little support for the views that adolescent animals are more sensitive to the neurobehavioral effects of repeated exposure to nicotine and that exposure to nicotine in adolescence may contribute to enhanced vulnerability to ethanol abuse. Furthermore, genetic predisposition to high or low ethanol self-administration does not seem to be a factor that influences individual vulnerability to the neurobehavioral effects of repeated administration of nicotine. [source] Parental rearing and substance related disorders,a multi-factorial controlled study in a Swedish sampleCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 6 2004P. Andersson Dysfunctional parental rearing was investigated to evaluate cognitive self-protective strategies in a high-risk sample from the Methadone Maintenance Programme, Stockholm, Sweden, and healthy subjects respectively. The Bowlby-Scale, the ASQ-SWED, the Reciprocal Attachment Questionnaire, the Dysfunctional Attitudes Scale and the Dysfunctional Working Models Scale were used. Results confirm insecure attachment (types A, C, D) among addicts and secure attachment (type B) among controls. The influence of the pathological pattern Compulsive self-reliance on the personality factor Confidence in self and others was 40.3 times higher (odds ratio) for addicts. The content of schemas in substance-related disorders shows an individual vulnerability associated with a decreased social competence and a very high risk for the development of various types of psychopathology. On the other hand, findings obtained in control subjects attest to a ,normal' organization of self-protective strategies and a pattern of behaviour mainly based on secure attachment.,Copyright © 2004 John Wiley & Sons, Ltd. [source] Research Beyond the Pale: Whiteness in Audience Studies and Media EthnographyCOMMUNICATION THEORY, Issue 2 2005Vicki Mayer This article examines the role of whiteness as a structuring absence to ethnographic audience research. After ignoring whiteness altogether, media ethnographers have tended to essentialize whiteness within narratives of structural dominance or individual vulnerability. Using poststructuralist theories of language, whiteness, and hegemony, the author argues that these narratives for whiteness can be traced to experiences in the field that are shaped by historical and institutional forces outside of the field. Researchers both perform whiteness in the field, by claiming its privilege and hiding its visibility, and codify whiteness for others to identify outside the field. To illustrate, the author examines "narcissistic whiteness" and "defensive whiteness" as two articulations that are visible in her own field notes, interpreted through unifying narratives and rearticulated through an alternative reading of the notes. [source] |