1,721,847 research outputs found
Opiate versus psychostimulant addiction: the differences do matter
No full textThe publication of the psychomotor stimulant theory of addiction in 1987 and the finding that addictive drugs increase dopamine concentrations in the rat mesolimbic system in 1988 have led to a predominance of psychobiological theories that consider addiction to opiates and addiction to psychostimulants as essentially identical phenomena. Indeed, current theories of addiction - hedonic allostasis, incentive sensitization, aberrant learning and frontostriatal dysfunction - all argue for a unitary account of drug addiction. This view is challenged by behavioural, cognitive and neurobiological findings in laboratory animals and humans. Here, we argue that opiate addiction and psychostimulant addiction are behaviourally and neurobiologically distinct and that the differences have important implications for addiction treatment, addiction theories and future research
Role of dopamine in dorsal medial prefrontal cortex in yohimbine-induced reinstatement of food seeking in rats
Full text linkIn humans, relapse to maladaptive eating habits during dieting is
often provoked by stress.Weadapted a drug relapse-reinstatement
model to study the role of stress in relapse to food seeking
(Nair et al., Prog. Neurobiol., 2009). In our model, the anxiogenic
drug yohimbine, an alpha-2 adrenoceptor antagonist, that causes
stress-like responses in humans and laboratory animals, reliably
reinstates food seeking.Werecently found that yohimbine-induced
reinstatement of food seeking is attenuated by systemic injections
of SCH23390 (a D1-family receptor antagonist) but not clonidine
(an alpha-2 adrenoceptor agonist). Here, we studied the role of
the medial prefrontal cortex (mPFC) in yohimbine-induced reinstatement.
We trained food-restricted rats to lever-press for 35%
high-fat pellets every other day (9–15 3 h sessions). We then extinguished
the food-reinforced operant responding for 10–14 days by
removing the pellets. Subsequently, we tested the effect of systemic
injections of yohimbine (0, 2 mg/kg) on reinstatement of food
seeking. In Exp. 1we found that yohimbine-induced reinstatement
was associated with strong induction of Fos (a marker of neuronal
activity) in the dorsal mPFC and weaker Fos induction in the ventral
mPFC. In Exp. 2 we found that dorsal but not ventral mPFC
injections of the D1-family receptor antagonist SCH23390 (0.5,
1.0g/side) decreased yohimbine-induced reinstatement of food
seeking. Our data indicate a critical role of dorsal mPFC dopamine in
reinstatement food seeking induced by the pharmacological stressor
yohimbine
Immobilization stress-induced oral opioid self-administration and withdrawal in rats: role of conditioning factors and the effect of stress on “relapse” to opioid drugs
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Faculty Opinions recommendation of Inflammatory Pain Promotes Increased Opioid Self-Administration: Role of Dysregulated Ventral Tegmental Area μ Opioid Receptors.
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Faculty Opinions recommendation of Trying to make sense of rodents' drug choice behavior.
No full textFaculty Opinions recommendation of Repeated restraint stress exposure during early withdrawal accelerates incubation of cue-induced cocaine craving.
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