Andrew Strasser

A Measure of Perceived Argument Strength: Reliability and Validity.

Studies of the content of persuasive messages in which the central arguments of the message are scrutinized have traditionally relied on the technique of thought-listing to assess argument strength. Although the validity of the thought-listing procedure is well documented, its utility can be limited in situations involving nonadult populations and sensitive topics. In this paper, we present a self-reported scale that can be used to assess perceived argument strength in contexts where thought-listing may be less appropriate. This scale taps into perceived argument strength from multiple points of view, including but also extending beyond the potential of the argument to elicit positive and negative thoughts. Reliability and validity of this scale were assessed in health communication contexts involving anti-drug public service announcements (PSAs) directed at adolescents and anti-smoking PSAs targeting adults. Evidence of convergence between this scale and the thought-listing technique was also obtained using the classical comprehensive exam arguments.

Effect of abstinence challenge on brain function and cognition in smokers differs by COMT genotype

The val allele of the catechol-O-methyltransferase (COMT) val158met polymorphism has been linked with nicotine dependence and with cognitive performance in healthy volunteers. We tested the hypothesis that the val allele is a risk factor for altered brain function and cognition during nicotine abstinence as compared with the normal smoking state. Chronic smokers (n=33) were genotyped prospectively for the COMT polymorphism for balanced selection of met/met, val/met and val/val groups. A visual N-back working memory task was performed during two separate blood oxygen level-dependent (BOLD) functional magnetic resonance imaging sessions in counterbalanced order: (1) smoking as usual, and (2)⩾14 h confirmed abstinence. Significant genotype by session interactions were observed for BOLD signal in right dorsolateral prefrontal cortex (DLPFC; (P=0.0005), left DLPFC (P=0.02) and dorsal cingulate/medial prefrontal cortex (P=0.01) as well as for task reaction time (P=0.03). Smokers with val/val genotypes were more sensitive to the abstinence challenge than carriers of the met allele, with the greatest effects on BOLD signal and performance speed at the highest working memory load. These data suggest a novel brain–behavior mechanism that may underlie the increased susceptibility to nicotine dependence and smoking relapse associated with the COMT val allele. Exploration of the effects of COMT inhibitors as a possible smoking cessation aid in this group may be warranted.

Reduced nicotine reward in obesity: cross-comparison in human and mouse.

RationaleTobacco use and obesity lead to significant morbidity and mortality.ObjectiveThis study was conducted to investigate the factors maintaining smoking behavior in lean and obese individuals by utilizing a mouse/human cross-validation model of nicotine reward.MethodsIn humans, a cigarette choice paradigm was used to examine the relative reinforcing value of nicotine in obese and non-obese smokers. Conditioned place preference (CPP) for nicotine was assessed in mice fed standard low fat rodent chow and mice rendered obese by a high fat diet.ResultsIn humans, obese smokers self-administered nicotine via cigarettes significantly less often than non-obese smokers and showed attenuated hedonic effects of nicotine-containing cigarettes compared to denicotinized cigarettes. Similarly, mice exposed to a high fat diet did not exhibit nicotine CPP, relative to control mice. mRNA levels for mu-opiate and leptin receptors were also downregulated in the ventral tegmental area of these mice.ConclusionsTogether, these studies provide the first evidence for reduced nicotine reward in obese subjects and suggest that this may be mediated by dietary influences on the endogenous opioid system.

Content Matters: Neuroimaging Investigation of Brain and Behavioral Impact of Televised Anti-Tobacco Public Service Announcements

Televised public service announcements are video ads that are a key component of public health campaigns against smoking. Understanding the neurophysiological correlates of anti-tobacco ads is an important step toward novel objective methods of their evaluation and design. In the present study, we used functional magnetic resonance imaging (fMRI) to investigate the brain and behavioral effects of the interaction between content (“argument strength,” AS) and format (“message sensation value,” MSV) of anti-smoking ads in humans. Seventy-one nontreatment-seeking smokers viewed a sequence of 16 high or 16 low AS ads during an fMRI scan. Dependent variables were brain fMRI signal, the immediate recall of the ads, the immediate change in intentions to quit smoking, and the urine levels of a major nicotine metabolite cotinine at a 1 month follow-up. Whole-brain ANOVA revealed that AS and MSV interacted in the inferior frontal, inferior parietal, and fusiform gyri; the precuneus; and the dorsomedial prefrontal cortex (dMPFC). Regression analysis showed that the activation in the dMPFC predicted the urine cotinine levels 1 month later. These results characterize the key brain regions engaged in the processing of persuasive communications and suggest that brain fMRI response to anti-smoking ads could predict subsequent smoking severity in nontreatment-seeking smokers. Our findings demonstrate the importance of the quality of content for objective ad outcomes and suggest that fMRI investigation may aid the prerelease evaluation of televised public health ads.

Effects of atomoxetine on subjective and neurocognitive symptoms of nicotine abstinence

Abstract Nicotine dependence has been linked to attention-deficit hyperactivity disorder (ADHD) symptoms in both clinical and general populations. This behavioural pharmacology study used a within-subject, double-blind, crossover design to test the effects of atomoxetine, a medication for ADHD, on nicotine abstinence symptoms. Fifty non treatment–seeking smokers (≥15 cigarettes/day) completed a baseline session when they were smoking as usual and then two laboratory testing sessions after overnight abstinence and treatment with 7 days of either atomoxetine (1.2 mg/kg) or placebo. During each laboratory session, participants completed subjective measures of abstinence symptoms and performed neurocognitive tasks. In mixed effects models, atomoxetine, compared with placebo, was found to be associated with a reduction in abstinence-induced subjective withdrawal symptoms. Atomoxetine was also associated with significant reductions in self-reported smoking urges amongst smokers who scored high on a baseline measure of smoking for stimulation. However, atomoxetine had no effect on any of the cognitive tasks employed in the study. Thus, atomoxetine may reduce cravings to smoke among smokers who use nicotine to increase arousal.

CREB1 haplotypes and the relative reinforcing value of nicotine.

depressed patients. This curvilinear relationship has also been clearly demonstrated using nortriptyline (but not desipramine) in the tail suspension test, an animal model for screening antidepressant drugs, in which a self-inhibiting effect of nortriptyline is evident when high doses are used. Thus, our findings show that the observed clinical therapeutic window found for nortriptyline is mimicked in certain brain areas at molecular level, as measured by c-Fos expression. The mechanisms explaining the inverted U-shaped dose-response effect of nortriptyline in clinical practice require further elucidation. The occurrence of a similar phenomenon regarding c-Fos expression in the group of animals receiving nortriptyline demonstrated here also needs clarification. There is some evidence that hydroxy-metabolites may be involved in the self-inhibiting effect of nortriptyline. Indeed, nortriptyline-treated, depressed patients with high plasma levels of E-10-OH-nortriptyline have been shown to respond poorly or not at all to the treatment. In this situation, the self-inhibitory effect of nortriptyline may be explained by the fact that, at high doses, increased plasma levels of nortriptyline hydroxy-metabolites with lower therapeutic efficacy exert a pharmacological competition with the parent compound, reducing its effect. Additionally, some of the brain areas in which the pattern of c-Fos expression appears as an inverted U-shaped dose– response curve are related to depression. Indeed, altered hippocampal volume detected by neuroimaging studies has been reported in humans. Also, the hypothalamic areas studied here are involved in the regulation of hypothalamic–pituitary–adrenal function, a neuroendocrine axis that is closely related to the mechanisms triggering and maintaining depression. The data presented here suggest that the MPOL, MnPO, PVN, SCh, CA1 and AHiPM may be involved in depression and that functional image-based protocols should be used to scrutinize their function in depressed patients.

Do Emotional Appeals in Public Service Advertisements Influence Adolescents’ Intention to Reduce Consumption of Sugar-Sweetened Beverages?

Mass media campaigns are a commonly used approach to reduce sugary drink consumption, which is linked to obesity in children and adolescents. The present study investigated the direct and mediated effects of emotional appeals in public service advertisements (PSAs) that aired between 2010 and 2012 on adolescents’ intention to reduce their sugar-sweetened beverage (SSB) consumption. An online randomized experiment was conducted with a national sample of adolescent respondents ages 13 to 17 years old (N = 805). Participants were randomly assigned to 1 of 4 conditions. Three experimental conditions represented PSAs with different emotional appeals: humor, fear, and nurturance, plus a fourth control condition. The outcome was adolescents’ intention to cut back on SSBs. The direct effect of fear appeals on intention was mediated through adolescents’ perception of the PSAs’ argument strength; perceived argument strength was also the key mediator for the indirect effects of humor and nurturance on intention. Several hypothesized mediators influenced by the appeals were not associated with intention. This is the first study to test the effect of persuasive emotional appeals used in SSB-related PSAs. The perceived strength of the PSAs’ arguments is important to consider in the communication of messages designed to reduce SSB consumption.