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Body dissatisfaction is supposed to rely on one’s own evaluations, but also depends on the perceived approval of other people. Thus, previous experiments paired participants’ own bodies with smiling faces. We decided to use a methodology similar to those used in previous experiments. Our 21 USs consisted of positive photographs. Each US+ corresponded to smiling women’s faces of different ages and skin color. Each photograph had been pretested to (a) elicit a positive affective response and to (b) correspond to “ordinary people” and not to a feminine ideal (e.g., photoshopped models seen in advertising; see example Figure 1). This last choice was made to avoid the social comparison effect which could increase body dissatisfaction (Tiggemann and McGill, 2004).

USs+examples on the top line, USsNexamples on the bottom line.

Our 21 NSs consisted of neutral photographs. These NSs corresponded to photographs of neutral objects from everyday life (e.g., keys, chair, door handles, and rubber bands). Each photograph had been selected from a pretest to (a) elicit a neutral affective response and to (b) not be related to eating or beauty (see example Figure 1).

All photographs were Creative Commons Zero images found on the Internet.

Three photographs of each participant were taken by experimenters and were used as CSs. One photograph was of the participant’s face, two photographs were of the participant’s full body (front and profile) wearing their own clothes.

For the EC condition, we designed a brief game-like app, inspired by the app designed by Franklin et al. (2016). In our study, each game session began with the presentation of three different pairs of photographs that the participant was instructed to remember. Pairs were composed of one CS and one US+. CS-US+ associations were randomly determined by the app at the beginning of each session. During the game, at each trial, one of these three pairs appeared among distractor photographs. The participant’s task was to select these pairs as quickly as possible. Distractor photographs corresponded to other USs+. Each game session contained 60 trials. At the end of each trial, the participant received feedback about the accuracy of the response (a red or green screen for 100 ms). Every 15 trials, the game became harder as more distractors were added and other response options were blacked out when the first option was selected (see Figure 2). Points were awarded for fast and accurate responses; this score was displayed at the end of each session. Thus, at each trial, participants associated an image of their body and a specific US+ by successively selecting a photograph of their own body and the target US+ (sequential pairing). Moreover, each time a participant saw a photograph of their own body, this was accompanied by other USs+ (distractors) on the screen (simultaneous pairing). This constituted an EC procedure in which the participant’s body was paired with pleasant stimuli in several ways.

Screenshots of app for the EC condition. Shapes were replaced by participants pictures in the real app. Step 1: The sessions begin with a screen displaying pairs to learn. Step 2: Game session begins with 2 × 2 grid for the first 15 trials. Step 3: Alternative options are masked after the first pair member is selected for the second 15 trials. Step 4: Grid moves to a 2 × 4 grid for the third 15 trials. Step 5: Alternative options are masked after the first pair member is selected for the last 15 trials.

For the neutral condition, the same methodology was applied, however, NSs were used instead of positive stimuli (USs+).

The EDI-2 (Garner, 1991; French version: Criquillon-Doublet et al., 1995) measures eating disorder symptoms and associated psychological traits. In this study we focused on attitudes and behaviors concerning eating, weight, and shape. Thus, we only used the 23 items in the subscales measuring drive for thinness, bulimia and body dissatisfaction. These items were adapted to only take the last 7 days into account. In our sample, Cronbach’s Alpha (internal consistency) of the EDI-2 subscales drive for thinness and body dissatisfaction were, respectively 0.75 and 0.90 at pre-test and 0.81 and 0.92 at post-test. Cronbach’s Alpha for the bulimia subscale at post-test was 0.80.

The CDRS (Thompson and Gray, 1995) consists of nine drawings of a female figure (for female participants). Each drawing increases in size from extremely thin to very obese. Participants are asked to rate their ideal figure and their current size (perceived figure). The discrepancy between ideal and current size scores constitutes an index of body size dissatisfaction.

The EDE-Q (Fairburn and Beglin, 1994; French version: Mobbs and Van der Linden, unpublished) measures eating disorder psychopathology over the last 28 days. In this study we only used the five items of the Restraint subscale. These items were adapted to only take the last 7 days into account. In our sample, Cronbach’s Alpha of EDE-Q was 0.85.

The CES-D (Radloff, 1977; French version: Bouvard et al., 2013) consists of 20 items that measure depressive symptomatology in the general population. In our sample, Cronbach’s Alpha of CES-D at pre-test and post-test were, respectively 0.92 and 0.94.

The RSES (Rosenberg, 1965; French version: Vallieres and Vallerand, 1990) consists of ten items that measure both positive and negative feelings about the self. In our sample, Cronbach’s Alpha of RSES at pre-test and post-test were, respectively 0.91 and 0.92.