The power of social influence over food intake: examining the effects of attentional bias and impulsivity (original) (raw)
Social modeling of eating: A review of when and why social influence affects food intake and choice
A major determinant of human eating behavior is social modeling, whereby people use others' eating as a guide for what and how much to eat. We review the experimental studies that have independently manipulated the eating behavior of a social referent (either through a live confederate or remotely) and measured either food choice or intake. Sixty-nine eligible experiments (with over 5800 participants) were identified that were published between 1974 and 2014. Speaking to the robustness of the modeling phenomenon, 64 of these studies have found a statistically significant modeling effect, despite substantial diversity in methodology, food type, social context and participant demographics. In reviewing the key findings from these studies, we conclude that there is limited evidence for a moderating effect of hunger, personality, age, weight or the presence of others (i.e., where the confederate is live vs. remote). There is inconclusive evidence for whether sex, attention, impulsivity and eating goals moderate modeling, and for whether modeling of food choice is as strong as modeling of food intake. Effects with substantial evidence were: modeling is increased when individuals desire to affiliate with the model, or perceive themselves to be similar to the model; modeling is attenuated (but still significant) for healthy-snack foods and meals such as breakfast and lunch, and modeling is at least partially mediated through behavioral mimicry, which occurs without conscious awareness. We discuss evidence suggesting that modeling is motivated by goals of both affiliation and uncertainty-reduction, and outline how these might be theoretically integrated. Finally, we argue for the importance of taking modeling beyond the laboratory and bringing it to bear on the important societal challenges of obesity and disordered eating.
External eating, impulsivity and attentional bias to food cues
Appetite, 2011
Cognitive and behavioural responses to food reward, such as attentional biases and overeating, have been associated with individual differences in reward-responsiveness and impulsivity. This study investigated relationships between external eating, impulsivity and attentional bias to food cues, assessed using the pictorial visual-probe task. As previously reported, attentional bias correlated positively with external eating. Additional novel findings were: (i) attentional bias for food cues was positively related to trait impulsivity, (ii) attentional bias remained related to attention impulsivity after controlling for external eating. Our findings highlight the relationship between the ability to control impulsive responding and selective attention to food cues. ß
The effect of social cues on the eating behavior of obese and normal subjects1
Journal of Personality, 1980
Schachter's externality hypothesis suggests that overweight individuals are more likely to be induced to eat by salient external cues than normal weight individuals. While a range of studies have demonstrated the plausibility of this hypothesis in the case of sensory stimuli (e.g., taste cues), there is little evidence that the hypothesis applies to social stimuli. The current study examines this latter propqs^itii)n bj/ exposing jnale and female, overweight and nQK[iial_weight^uljjects to a same-sex or oppositesex peer model. Under the..guise_of engaging in a'taste experiment, the subjeets-'W'gfe'either exposed to a moTIel who tasted no crackers (no eat), one cracker (lQw_eM3j.PX.tWjentycrackeTS-(lrtgh eat). In addition, control model-absent conditions were also run for purposes of establishing baseline eating rates. If tlie_extejiiality-hyp6thes.es, were to prevail iri^social domains, one would expect overweight subjects to be more prone to model the frarker-eaTjn^^^ehayior 7vf~fhe pper than normal weiglit individuals. However, the findings indicate that all subject groups regardless of weight evidence a rath'grTleaf'm(5delinig_effect and all subjects evidence social inKTBItion efrects~oif"ffieTr eating beKavior as well. Several intr^uing interactlons among subject sex!, model~»ex;"sTIbJert-Wfeight, and social condition were also found. The discussion explores the relevance of an externality model of overweight eating in social domains, and focuses upon the interesting and somewhat distinct pattern of socially mediated eating exhibited by overweight females.
Modeling influences on eating behavior
Addictive Behaviors, 1979
Some aspects of social influence on eating behavior have been examined but no studies have looked at direct influences of one person's eating behavior on that of another. Two experiments assessed whether people model rate of eating and amount of food consumed by another person. In Experiment I, female college students ate a standardized luncheon with a confederatemodel peer, who ate her lunch at a predetermined fast (12min) or slow (25min) rate. Subjects who ate with fast-eating confederate-models consumed their lunches at a significantly faster rate than subjects who ate with slow-eating confederate-models. In Experiment II, same and opposite sex pairs of subjects and confederate-models participated in a "cracker tasting" task. The confederate-model ate either a high (40) or low (10) number of crackers in 7min. Subjects eating with a high consumption male confederate-model ate more crackers than subjects who ate with a low consumption male or female confederate-model. But, subjects who ate with a high consumption female confederate-model did not differ from the other groups in number of crackers eaten. These findings may be important for treating obesity, if modeling also occurs in natural situations.
Appetite, 2012
The present study experimentally tested whether the effect of olfactory food-cue exposure on young women's food intake was moderated by the duration of the cue exposure and trait impulsivity. The study employed a 2 (food-cue exposure: smell of baked cookies present vs. no-smell present) by 2 (duration of cue exposure: short-term vs. long-term) between-participants design. Participants were 109 normalweight young women (mean age = 21.6 years) whose food intake was examined during a bogus tastetest. Additional saliva measures were taken during food-cue exposure. Results showed that the duration of the cue exposure did not affect intake. Impulsivity moderated intake, but not saliva flow. Low impulsive females consumed more food when confronted with an olfactory food-cue, whereas high-impulsive females did not eat more after food-cue exposure. Our findings may be explained by the fact that we did not instruct our participants to pay attention to the olfactory food-cue. Results indicate that even people who are normally well controlled are susceptible to the effects of less explicit olfactory food-cues.
Effects of an observer on eating behavior: The induction of "sensible" eating1
Journal of Personality, 1979
An experiment was conducted to investigate the extent of caloric compensation to differential preloading among normally restrained and unrestrained female subjects. Subjects' eating was either explicitly observed or unobserved by the experimenter. Unrestrained eaters compensated appropriately for the preload, whether or not they were observed. Restrained eaters failed to compensate when unobserved, but compensated strongly when observed. A subsequent unobserved eating task revealed that restrained eaters failed to compensate for prior consumption when the observer was withdrav(m. Implications for research and therapy are discussed.
Psychology of Addictive Behaviors, 2009
Many studies have demonstrated that those high in weight-related concerns eat more after food-cue exposure, which is consistent with predictions of the cue-reactivity model. However, the counteractivecontrol model predicts that exposure to fattening foods activates dieting-related goals and behavior in weight-concerned individuals. Although these models seem incongruous, the authors hypothesized that the salience of the cue could represent a critical factor in determining which model is activated. The authors predicted that attending to salient food cues would result in increased intake (cue reactivity) in individuals with high weight-related concerns, whereas incidental food-cue exposure would result in decreased intake (counteractive control), relative to control exposure. The authors employed a 3 (attended vs. incidental vs. control cue) ϫ 2 (low vs. high weight-related concerns) design. As expected, participants with high weight-related concerns who attended to a food cue ate more than did both those with high weight-related concerns in the control condition and those with low weight-related concerns in the attended-cue condition; however, intake of individuals with high weight-related concerns who were exposed to the incidental cue did not differ from that of those in the control condition. The manner of food-cue presentation may be a critical factor in determining eating behavior.
Situational effects on meal intake: A comparison of eating alone and eating with others
Physiology & Behavior, 2006
Eating in competition with other tasks has been shown to increase food intake, particularly when tasks are cognitively demanding. To test the hypothesis that social facilitation of eating occurs, in part, as a function of distraction which impairs the ability to self-monitor, eating with others was compared with eating alone or in front of the television. Using a repeated measure within-subjects design, thirty-seven participants (21 males) visited the laboratory 4 times to eat a buffet-style lunch ad libitum. All eating episodes were filmed. Energy intake (EI) was measured when participants ate alone (A), ate alone while watching TV (B), ate with two same sex strangers (C), and ate with two same sex friends (D) in a counterbalanced order. EI was significantly enhanced by presence of familiar others (D: 4565 ± 272 kJ, p b 0.001) and watching TV (B: 4350 ± 252 kJ, p b 0.05) compared to baseline (A: 3861 ± 200 kJ). Length of eating episode correlated significantly (p b 0.05) with EI, however, amount of time spent eating and looking at food differed by condition with a greater percentage of time focussed on food during baseline (p b 0.001). Eating with friends increased EI by 18% and eating in front of the TV increased EI by 14% relative to baseline. Engaging in conversation or watching TV draws attention away from the eaten food and can stimulate food intake. However, since eating with strangers also drew attention away from food but did not result in increased intake, social facilitation effects are not simply due to distraction. Thus food intake can be enhanced when attention to food and self-monitoring are impaired during distraction, however, this effect is moderated when eating with strangers.
Effects of a model on eating behavior: The induction of a restrained eating style1
Journal of Personality, 1979
An experiment was conducted to assess the effects of a same-sex model on females' eating behavior. The model ate either a large or small quantity along with the subject in an ad lib satiation context, and either did or did not identify herself as a dieter. Subjects were 86 female undergraduates, split into normally dieting or nondieting subgroups. Number of sandwich quarters consumed ad lib following a small fixed preload was found to vary as a function of (a) model's consumption (b) model's dieter status and (c) subject's dieter status; there were no significant interactions. A subsequent taste-rating assessment of nut consumption, in which the model was present but could neither see nor be seen by the subject, indicated that the three factors which had previously affected sandwich consumption independently combined to affect nut consumption interdependently. The results were interpreted in terms of the effect of the model on tbe quantity and pattern of consumption, and conclusions were drawn about the dynamics of restrained and unrestrained eating and implications for therapy.