Decreased insular and increased midbrain activations during decision-making under risk in adolescents with excess weight
Disclosures: The authors declared no conflicts of interest.
Funding agencies: This study has been funded by grants PI 0416/2008 (BRAINOBE) from the Andalusian Health Service (Consejería de Salud), PSI2010-17290 (INTEROBE) from the Ministry of Innovation and Science (MICINN), and P-10-HUM-6635 (NEUROECOBE). Dr. Soriano-Más is funded by a Miguel Servet contract from the Carlos III Health Institute (CP10/00604).
Correspondence: Antonio Verdejo-García (firstname.lastname@example.org or email@example.com)
Functional magnetic resonance imaging (fMRI) was used to explore the brain substrates of decisions under risk in excess weight adolescents. Decreased activations of the brain regions signaling risk (orbitofrontal cortex [OFC], insula) were expected during anticipation of higher rewards and increased activations of the brain regions involved in reward processing (OFC, striatum) were expected after reward receipt in excess weight adolescents compared to normal weight controls.
Design and Methods
Fifty-two adolescents (age range 12-17), classified in three groups as a function of BMI: obese (n = 21), overweight (n = 15), or normal weight (n = 16) performed the Risky-Gains task as described by Paulus et al. in the fMRI scanner.
Excess weight adolescents, compared to normal weight controls, showed decreased left insular and increased midbrain activations during anticipation of risky choices. In addition, excess weight adolescents showed increased activations of the inferior frontal gyrus, parahippocampus, thalamus, and posterior brain regions after reward receipt.
Adolescents with excess weight showed reduced activations in brain regions signaling risk and increased activations in regions signaling reward during anticipation of decisions involving risk and reward. In addition, post-decision reward outcomes produced increased activations of regions involved in emotional salience in excess weight adolescents versus controls.