Interference effect of food and emotional stimuli in Stroop-like tasks for children and adults with Prader-Willi Syndrome

ABSTRACT

Interference effect of food and emotional stimuli in Stroop-like tasks for children and adults with Prader-Willi Syndrome. The aim of this work was to study the way items related to food or emotion are processed by a population known to have difficulties with dietary restriction, namely individuals with Prader-Willi Syndrome (PWS). Given the presence of intellectual disability (ID) in PWS, our experiments were designed to examine whether these difficulties were specific to PWS or linked with their ID. Two modified Stroop tasks (i.e., a food version and an emotional version) were administered to seventy-four children (aged between 6 and 16 years old) divided into three groups (one with PWS, one with ID matched on age and Intellectual Quotient (IQ), and one healthy group matched on age) and to eighty-four adults (aged between 18 and 48 years old) distributed in the same three groups. For both tasks, a picture version was used for the children and a word version for the adults. For the food Stroop task, (Experiment 1), materials were composed of low or high-caloric food items and stimuli not related to food. The results show a food Stroop effect for children and adults with PWS that was absent in the group of healthy participants. Moreover, a food Stroop effect was also significant for adults with ID. For the emotional Stroop task (Experiment 2), materials were composed of negative, positive and neutral stimuli. The emotional Stroop effect was also obtained for children and adults with PWS as well as for the healthy group, but not for the age- and IQ-matched group. For the PWS groups, results show a preservation to process positive pictures for children and difficulties to process negative stimuli for both age-groups. These results suggest that people with PWS have difficulties in disengaging their attention when food stimuli are present in their environment and poorer abilities to process negative ones. These difficulties endure in adulthood.

KEYWORDS:

• Prader-Willi Syndrome
• interference effect
• emotional valence
• food relationship
• children
• adults

Author Notes

Coauthor: Stéphanie Mathey, Laboratoire de Psychologie EA 4139, Université de Bordeaux, Email: [email protected].

Christelle Robert, Laboratoire de Psychologie EA 4139, Université de Bordeaux, Email: [email protected].

Séverine Estival, Laboratoire de Psychologie EA 4139, Université de Bordeaux, E-mail: [email protected].

Johann Chevalère, Department of Educational Sciences, University of Postdam, Postdam, Germany, E-mail: [email protected].

Jenna Maire, Unité de recherche CERES, Institut Catholique de Toulouse, Toulouse, France, E-mail: [email protected].

Maïthé Tauber, Center de référence du syndrome de Prader-Willi, Pédiatrie - Endocrinologie, génétique et gynécologie médicale, CHU de Toulouse, Hôpital des Enfants, Toulouse, France, E-Mail: [email protected].

Virginie Laurier, Center de référence du syndrome de Prader-Willi, AP-HP Hôpital Marin, Hendaye, France, E-mail: [email protected].

Julie Tricot, Center de référence du syndrome de Prader-Willi, AP-HP Hôpital Marin, Hendaye, France, E-mail: [email protected].

Fabien Mourre, Center de référence du syndrome de Prader-Willi, AP-HP Hôpital Marin, Hendaye, France, E-mail: [email protected].

Virginie Postal, Laboratoire de Psychologie EA 4139, Université de Bordeaux, E-mail: [email protected].

Acknowledgments

We sincerely thank all the participants of this study and the staff at referral centers for Prader-Willi Syndrome for their involvement in this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1. Item number from the Food-Pics database: High-caloric: 0016, 0018, 0022, 0027, 0061, 0065, 0082, 0100, 0128, 0145, 0156, 0177, 0188, 0304, 0327, 0350, 0378, 0426, 0492, 0539; Low-caloric: 0198, 0222, 0238, 0245, 0254, 0258, 0275, 0282, 0285, 0334, 0368, 0389, 0391, 0396, 0398, 0401, 0415, 0433, 0508, 0528; Control: 1002, 1005, 1016, 1019, 1033, 1055, 1059, 1144, 1187, 1210, 1219, 1222, 1223, 1231, 1259, 1267, 1271, 1273, 1274, 1314.

2. The rank of age in our sample been large and potentially influenced the data, we run the new analyses with age factor as a covariate. Results showed that adding age of children as a covariate doesn’t change the significance of the interaction effect between groups and the food Stroop effect (p < .001) or of the main food Stroop effect (p < .001). Moreover, to test the possible influence of sex we ran the same analyses with sex of participants as a covariate. The significance of the main Food Stroop effect persisted (p < .001) as well as the interaction effect between the type of stimuli and groups of participants (p < .001).

3. To test the possible influence of participant’s sex we ran the new analyses with this variable as a covariate. The significance of the main Food Stroop effect persisted (p < .001) as well as the interaction effect between the type of stimuli and groups of participants (p = .041).

4. Item number from the IAPS: Negative: 1050, 1205, 2095, 2301, 2810, 2900, 9050, 9171, 9210, 9220, 9280, 9291, 9421, 9429, 9471, 9600, 9831, 9940 (2 more were taken from the internet); Positive: 1340, 1463, 1750, 1811, 1920, 1999, 2091, 2216, 2340, 2345, 2388, 2398, 2655, 2791, 5470, 5760, 8490, 8620 (2 more were taken from the internet); Neutral: 2026, 2191, 2214, 2230, 2377, 2396, 2593, 2745, 2880, 5395, 5740, 7026, 7033, 7036, 7165, 7217, 7546, 7595 (2 more were taken from the internet).

5. According to the remark of a reviewer about the large rank of age in our sample which may influence the data, we ran the same analyses with the age factor as a covariate. Results showed that adding age of children as a covariate doesn’t change the significance of the interaction effect between groups and the Emotional Stroop effect (p < .001) or of the main emotional Stroop effect (p = .009). Moreover, to test the possible influence of sex we ran the same analyses with participant’s sex as a covariate. The significance of the main Emotional Stroop effect persisted (p = .010) as well as the interaction effect between the valence of stimuli and groups of participants (p < .001).

6. As before, in order to test the possible influence of sex we ran the new analyses with this variable as a covariate. The significance of the main Emotional Stroop effect persisted (p < .001) as well as the interaction effect between the valence of stimuli and groups of participants (p < .001).

Additional information

Funding

This work was supported by the Fondation Maladies Rares;