The relationship between body dissatisfaction and attentional bias to thin bodies in Malaysian Chinese and White Australian women: a dot probe study

Studies suggest that an attentional bias to thin bodies is common among those with high levels of body dissatisfaction, which is a risk factor for, and symptom of, various eating disorders. However, these studies have predominantly been conducted in Western countries with body stimuli involving images of White people. In a preregistered study, we recruited 150 Malaysian Chinese women and 150 White Australian women for a study using standardized images of East Asian and White Australian bodies. To measure attentional bias to thin bodies, participants completed a dot probe task which presented images of women who self-identified their ethnicity as East Asian or as White Australian. Contrary to previous findings, we found no evidence for an association between body dissatisfaction and attentional bias to thin bodies. This lack of association was not affected by participant ethnicity (Malaysian Chinese versus White Australian) or ethnic congruency between participants and body stimuli (own-ethnicity versus other-ethnicity). However, the internal consistency of the dot probe task was poor. These results suggest that either the relationship between body dissatisfaction and attentional bias to thin bodies is not robust, or the dot probe task may not be a reliable measure of attentional bias to body size.

Is body dissatisfaction related to an attentional bias towards low weight bodies in non-clinical samples of women? A systematic review and meta-analysis

Body dissatisfaction is defined as the negative subjective evaluation of one's body and is considered a risk factor for, and symptom of, eating disorders. Some studies show women with high body dissatisfaction display an attentional bias towards low weight bodies; however, this finding is not consistent, and results are yet to be systematically synthesised. We conducted a qualitative and quantitative synthesis of cross-sectional studies investigating the relationship between body dissatisfaction and attentional bias to low weight bodies in non-clinical samples of women. We searched PubMed, Scopus, Web of Science, PsycINFO, ProQuest, and OpenGrey for studies up until September 2022. We identified 34 eligible studies involving a total of 2857 women. A meta-analysis of 26 studies (75 effects) found some evidence from gaze tracking studies for a positive association between body dissatisfaction and attentional bias to low weight bodies. We found no evidence for an association from studies measuring attention using the dot probe task, electroencephalogram (EEG) recording, or the modified spatial cueing task. The results together provide partial support for the positive association between body dissatisfaction and attentional bias to low weight bodies in women. These findings can be used to inform future attentional bias research.

Association of the 5- HTTLPR genotype and unipolar depression: a meta-analysis

BACKGROUND

We sought to ascertain the strength of evidence for association between the 5-HTTLPR polymorphism and unipolar depression.

METHOD

We applied meta-analytic techniques to data from relevant published studies, and obtained an estimate of the likely magnitude of effect of any association. We also tested for possible publication bias, and explored the impact of various study design characteristics on the magnitude of the observed effect size.

RESULTS

Meta-analysis indicated evidence of a small but statistically significant association between the 5-HTTLPR polymorphism and unipolar depression [odds ratio (OR) 1.08, 95% confidence interval (CI) 1.03-1.12]. This remained significant when data from samples of European and East Asian ancestry were analyzed separately. In all cases there was evidence of significant between-study heterogeneity, although the observed associations were robust to the application of a random-effects framework.

CONCLUSIONS

Our results support the presence of a small effect of a polymorphism in the serotonin transporter promoter on susceptibility to depression. However, we caution that it is possible that the effect has an artifactual basis, rather than a biological origin.

Effects of acute alcohol consumption and alcohol expectancy on processing of perceptual cues of emotional expression

We recently demonstrated that alcohol elicits a difference between men and women in perceptual threshold for facial expressions of sadness. However, this study did not include a manipulation of alcohol expectancy. Therefore, we sought to determine whether these effects may be due to the expectation of having consumed alcohol. Male and female participants (n = 100) were randomised using a balanced-placebo design to receive either an alcoholic or a non-alcoholic drink and to be told that this was alcoholic or non-alcoholic. Participants completed a psychophysical task which presented male and female faces expressing angry, happy, and sad emotions. Analysis of threshold data indicated a significant two-way interaction of drink x target emotion, reflecting a higher threshold for the detection of sad facial expressions of emotion, compared with angry or happy expressions, in the alcohol condition compared with the placebo condition. We did not observe any evidence of sex differences in these effects. Our data indicate that alcohol modifies the perceptual threshold for facial expressions of sadness. Unlike our previous report, we did not observe evidence of sex differences in these effects. Most importantly, we did not observe any evidence that these effects were due to expectancy effects associated with alcohol consumption.

Effects of acute alcohol consumption on processing of perceptual cues of emotional expression

Alcohol consumption has been associated with increases in aggressive behaviour. However, experimental evidence of a direct association is equivocal, and mechanisms that may underlie this relationship are poorly understood. One mechanism by which alcohol consumption may increase aggressive behaviour is via alterations in processing of emotional facial cues. We investigated the effects of acute alcohol consumption on sensitivity to facial expressions of emotion. Participants attended three experimental sessions where they consumed an alcoholic drink (0.0, 0.2 or 0.4 g/kg), and completed a psychophysical task to distinguish expressive from neutral faces. The level of emotion in the expressive face varied across trials the threshold at which the expressive face was reliably identified and measured. We observed a significant three-way interaction involving emotion, participant sex and alcohol dose. Male participants showed significantly higher perceptual thresholds for sad facial expressions compared with female participants following consumption of the highest dose of alcohol. Our data indicate sex differences in the processing of facial cues of emotional expression following alcohol consumption. There was no evidence that alcohol altered the processing of angry facial expressions. Future studies should examine effects of alcohol expectancy and investigate the effects of alcohol on the miscategorisation of emotional expressions.

Differential responsiveness to caffeine and perceived effects of caffeine in moderate and high regular caffeine consumers

RATIONALE

Individual differences in responsiveness to caffeine occur even within a caffeine-consuming population, but the factors that mediate differential responsiveness remain unclear.

OBJECTIVES

To compare caffeine's effects on performance and mood in a group of high vs moderate consumers of caffeine and to examine the potential role of subjective awareness of the effects of caffeine in mediating any differential responsiveness.

MATERIALS AND METHODS

Two groups of regular caffeine consumers (<200 mg/day and >200 mg/day) attended two sessions at which mood and cognitive functions were measured before and 30 min after consumption of 400-mg caffeine or placebo in a capsule. Cognitive tests included visual information processing, match-to-sample visual search (MTS) and simple and choice reaction times. Post-session questionnaires asked participants to describe any perceived effect of capsule consumption.

RESULTS

High consumers, but not moderate consumers, demonstrated significantly faster simple and choice reaction times after caffeine relative to placebo. These effects were not attributable to obvious group differences in withdrawal or tolerance because there were no group differences in baseline mood or in reports of negative affect after caffeine. Instead, the high consumers were more likely to report experiencing positive effects of caffeine, whereas the moderate consumers were more likely to report no effect.

CONCLUSIONS

The sensitivity of caffeine consumers to the mood- and performance-enhancing effects of caffeine is related to their levels of habitual intake. High caffeine consumers are more likely than moderate consumers to perceive broadly positive effects of caffeine, and this may contribute to their levels of use.