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IntroductionNeuroscience evidence suggests that adolescent obesity is linked to brain dysfunctions associated with enhanced reward and somatosensory processing and reduced impulse control during food processing. Comparatively less is known about the role of more stable brain structural measures and their link to personality traits and neuropsychological factors on the presentation of adolescent obesity. Here we aimed to investigate regional brain anatomy in adolescents with excess weight vs. lean controls. We also aimed to contrast the associations between brain structure and personality and cognitive measures in both groups.MethodsFifty-two adolescents (16 with normal weight and 36 with excess weight) were scanned using magnetic resonance imaging and completed the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ), the UPPS-P scale, and the Stroop task. Voxel-based morphometry (VBM) was used to assess possible between-group differences in regional gray matter (GM) and to measure the putative differences in the way reward and punishment sensitivity, impulsivity and inhibitory control relate to regional GM volumes, which were analyzed using both region of interest (ROI) and whole brain analyses. The ROIs included areas involved in reward/somatosensory processing (striatum, somatosensory cortices) and motivation/impulse control (hippocampus, prefrontal cortex).ResultsExcess weight adolescents showed increased GM volume in the right hippocampus. Voxel-wise volumes of the second somatosensory cortex (SII) were correlated with reward sensitivity and positive urgency in lean controls, but this association was missed in excess weight adolescents. Moreover, Stroop performance correlated with dorsolateral prefrontal cortex volumes in controls but not in excess weight adolescents.ConclusionAdolescents with excess weight have structural abnormalities in brain regions associated with somatosensory processing and motivation.

Adolescent obesity is increasingly viewed as a brain‐related dysfunction, whereby reward‐driven urges for pleasurable foods “hijack” response selection systems, such that behavioral control progressively shifts from impulsivity to compulsivity. In this study, we aimed to examine the link between personality factors (sensitivity to reward (SR) and punishment (SP), BMI, and outcome measures of impulsivity vs. flexibility in—otherwise healthy—excessive weight adolescents. Sixty‐three adolescents (aged 12–17) classified as obese (n = 26), overweight (n = 16), or normal weight (n = 21) participated in the study. We used psychometric assessments of the SR and SP motivational systems, impulsivity (using the UPPS‐P scale), and neurocognitive measures with discriminant validity to dissociate inhibition vs. flexibility deficits (using the process‐approach version of the Stroop test). We tested the relative contribution of age, SR/SP, and BMI on estimates of impulsivity and inhibition vs. switching performance using multistep hierarchical regression models. BMI significantly predicted elevations in emotion‐driven impulsivity (positive and negative urgency) and inferior flexibility performance in adolescents with excess weight—exceeding the predictive capacity of SR and SP. SR was the main predictor of elevations in sensation seeking and lack of premeditation. These findings demonstrate that increases in BMI are specifically associated with elevations in emotion‐driven impulsivity and cognitive inflexibility, supporting a dimensional path in which adolescents with excess weight increase their proneness to overindulge when under strong affective states, and their difficulties to switch or reverse habitual behavioral patterns.

The aim of this study was to explore the effects of a multidisciplinary behavioral intervention including cognitive behavioral therapy, structured physical activity, and dietary counseling on impulsive personality and cognitive skills and subsequent BMI loss in excess weight adolescents. Forty-two adolescents with excess weight (14 males and 28 females, range 12-17 years), as defined by the International Obesity Task Force Criteria, participated in our study. We used a longitudinal observational design with two assessments: before and after treatment. We collected baseline measures of impulsive personality (UPPS-P scale), cognitive performance (letter number sequencing, Stroop and Iowa gambling task), and biometric parameters. After 12 weeks of intervention, parallel measures were used to determine whether treatment-induced changes in impulsivity and cognition predicted changes in BMI. BMI showed a statistically significant reduction after treatment [from mean (SD) 29.36 (4.51) to 27.31 (4.41), Cohen's d=0.5]. Greater reductions in negative urgency (negative-emotion-driven impulsivity) and greater improvement in cognitive inhibitory control skills were associated with greater reductions in BMI. Because the design was correlational and lacked a control group, future studies should clarify whether these associations reflect a causal effect or just overlapping improvements associated with a third variable (e.g. increases in attention procurement or motivation).

Despite the numerous definitions and dimensions proposed to explain the sense of humor and the variety of instruments developed for its assessment, little attention has been paid to its affective and attitudinal basis in the models developed so far. The long form of the trait version of the State-Trait-Cheerfulness-Inventory (STCI-T; Ruch, Köhler, van Thriel, 1996) was developed using a facet approach to measure the temperamental basis of sense of humor using three theoretically-derived concepts: cheerfulness, seriousness, and bad mood. This paper presents the psychometric analysis of the Spanish long form of the trait version of the STCI-T. We assessed the dimensionality of the instrument, the internal consistency and test-retest reliability of its facets and scales and the relationships between STCI-T domains and other variables. We assessed four independent samples comprised of 1049 participants in total with ages ranging between 18 and 94 years. The psychometric characteristics appeared to be satisfactory and proved to be replicable. Moreover, relationships between (a) the temperamental basis of sense of humor and (b) personality and well-being were also replicated. Results provide validity evidence for using the Spanish version of the STCI-T to assess the temperamental basis of sense of humor in the Spanish population.