Laurent Waroquier

Is It Better to Think Unconsciously or to Trust Your First Impression?: A Reassessment of Unconscious Thought Theory

According to unconscious thought theory, complex decisions are best made after a period of distraction assumed to elicit “unconscious thought.” Here, the authors suggest instead that the superiority of decisions made after distraction results from the fact that conscious deliberation can deteriorate impressions formed on-line during information acquisition. The authors found that participants instructed to form an impression made better decisions after distraction than after deliberation, thereby replicating earlier findings. However, decisions made immediately were just as good as decisions made after distraction, which suggests (a) that people had already made their decision during information acquisition, (b) that deliberation without attention does not occur during distraction, and (c) that ruminating about ones first impression can deteriorate decision quality. Strikingly, in another condition that should have favored unconscious thought even more, deliberated decisions were better than immediate or distracted decisions. These findings were replicated in a field study.

Smaller Food Item Sizes of Snack Foods Influence Reduced Portions and Caloric Intake in Young Adults

Studies considering the impact of food-size variations on consumption have predominantly focused on portion size, whereas very little research has investigated variations in food-item size, especially at snacking occasions, and results have been contradictory. This study evaluated the effect of altering the size of food items (ie, small vs large candies) of equal-size food portions on short-term energy intake while snacking. The study used a between-subjects design (n=33) in a randomized experiment conducted in spring 2008. In a psychology laboratory (separate cubicles), participants (undergraduate psychology students, 29 of 33 female, mean age 20.3±2 years, mean body mass index 21.7±3.7) were offered unlimited consumption of candies while participating in an unrelated computerized experiment. For half of the subjects, items were cut in two to make the small food-item size. Food intake (weight in grams, kilocalories, and number of food items) was examined using analysis of variance. Results showed that decreasing the item size of candies led participants to decrease by half their gram weight intake, resulting in an energy intake decrease of 60 kcal compared to the other group. Appetite ratings and subject and food characteristics had no moderating effect. A cognitive bias could explain why people tend to consider that one unit of food (eg, 10 candies) is the appropriate amount to consume, regardless of the size of the food items in the unit. This study suggests a simple dietary strategy, decreasing food-item size without having to alter the portion size offered, may reduce energy intake at snacking occasions.

Split Them! Smaller Item Sizes of Cookies Lead to a Decrease in Energy Intake in Children

OBJECTIVE Examine the influence of altering the size of snack food (ie, small vs large cookies) on short-term energy intake. METHODS First- and sixth-graders (n = 77) participated in a between-subjects experimental design. All participants were offered the same gram weight of cookies during an afternoon tea at their school. For half of the participants, food was cut in 2 to make the small item size. Food intake (number of cookies, gram weight, and energy intake) was examined using ANOVA. RESULTS Decreasing the item size of food led to a decrease of 25% in gram weight intake, corresponding to 68 kcal. Appetitive ratings and subject and food characteristics had no moderating effect. CONCLUSIONS AND IMPLICATIONS Reducing the item size of food could prove a useful dietary prevention strategy based on decreased consumption, aimed at countering obesity-promoting eating behaviors favored by the easy availability of large food portions.

Gist Memory in the Unconscious-Thought Effect

The unconscious-thought effect (UTE) occurs when people are better able to make complex decisions after a period of distraction rather than immediately or after a period of conscious deliberation. This finding has often been interpreted as evidence of unconscious thinking. In two experiments, we provided the first evidence that the UTE is accompanied by enhanced memory for the gist of decision-relevant attributes and demonstrated that the cognitive demands of a distraction task moderate its effect on decision making and gist memory. It was only following a low-demand distraction task that participants chose the best alternative more often and displayed enhanced gist memory for decision-relevant attributes. These findings suggest that the UTE occurs only if cognitive resources are available and that it is accompanied by enhanced organization of information in memory, as shown by the increase in gist memory.

The interplay between presentation material and decision mode for complex choice preferences

Recent research suggests that, when faced with a choice between several alternatives described with a large number of attributes, people make better choices if they do not consciously ponder over the alternatives but rather perform a distraction task assumed to elicit unconscious thought. Subsequent research attempting to replicate this finding, however, provided mitigated support for its existence. The research reported here contributes to this ongoing debate on two grounds. First, it highlights a methodological confound between qualitative and quantitative presentation material and proposes a novel procedure that can accommodate both. Second, it shows that, whereas conscious deliberation leads to better decisions when alternatives are characterised by quantitative information, the use of a qualitative format for presenting information cancels the advantage of conscious deliberation.

The role of gist and verbatim memory in complex decision making: Explaining the unconscious-thought effect.

Previous research showed that the unconscious-thought effect, which refers to an improvement in complex decision making following a distraction period, was moderated by the presentation format of pieces of information about different options. The aim of the current study was to replicate this finding and further examine the memory representations underlying decision making following a distraction or a deliberation period. Results showed that, when the information was presented blocked per option, participants were better able to differentiate the best option from the others after a distraction period than immediately after the information presentation or after a deliberation period. In addition, distracted participants retrieved more gist representations of the options when the information was presented per option. By contrast, participants were better able to differentiate the best option from the others after a deliberation period when the information was presented per attribute. Participants who deliberated also retrieved more verbatim representations when the information was presented per attribute. Finally, mediation analyses indicated that the accuracy of the evaluations of the options depends on gist memory when distracted but on verbatim memory when deliberating. These findings suggest that the effectiveness of distraction or deliberation depends on the memory representations of the different options.