Examining Sex Differences in the Association Between Reward and Punishment Sensitivity and Disordered Eating Among Adolescents

Alyssa M. Izquierdo

Advisor: Sarah Fischer, PhD, Department of Psychology

Committee Members: Tara Chaplin, James Thompson

Online Location, Zoom
April 23, 2026, 09:00 AM to 11:00 AM

Abstract:

Eating disorders (EDs) are serious psychiatric illnesses with high mortality rates. Disordered eating can occur without a full diagnosis present and may precede the onset of a full diagnosis. Adolescence is a peak period of ED onset, and prevalence rates are high among girls and boys. The high prevalence of EDs in boys and girls highlights the need to identify and target underlying factors that may contribute to the development of EDs. One potential factor is altered reward processing, which includes behavioral responses activated by the neurobiological reward system. Reward sensitivity and punishment sensitivity are specific aspects of reward processing that refer to approach behavior to rewarding stimuli and avoidance behavior to aversive stimuli, respectively. In the past decade, neuroimaging studies have investigated neurobiological underpinnings of reward and punishment sensitivity during adolescent development. No studies have examined how neural reward and punishment based pathways are associated with ED symptoms in adolescent boys. As such, the present study will contribute to this research gap by examining sex differences in reward-related risk factors on eating disorder pathology.

The goal of the current two-study dissertation is to examine the association between reward and punishment sensitivity with disordered eating in adolescent girls and boys over time. I investigated the association between neural and behavioral responses to reward and punishment and disordered eating at baseline (Study 1) and one-year follow-up (Study 2) in early adolescence. I conducted secondary data analyses from a longitudinal parent study that included a sample of 249 adolescents (ages 11-14; 48% girls). Adolescents completed a functional magnetic resonance imaging (fMRI) card-guessing task with monetary gain (reward) and loss (punishment) outcome trials. Median reaction time (RT) for each trial was extracted and used for analyses. Self-reported eating pathology was measured with the Eating Pathology Symptoms Inventory (EPSI), which was collected at baseline and at one-year follow-up. Regression analyses were used to test main and interactive effects of neural (sex X BOLD response score) and behavioral (sex X median RT) responses on disordered eating. 

In Study 1, results revealed that BOLD response in the right anterior insula during monetary loss compared to neutral feedback was positively associated with restriction, and BOLD response in the right nucleus accumbens and caudate during monetary loss compared to neutral feedback was positively associated with binge eating. Further, in Study 1, results indicate that median RT during monetary gain interacted with sex to predict restriction.

In Study 2, neural responses to monetary loss and gain did not predict disordered eating at one year, after adjusting for baseline symptoms. Study 2 behavioral results revealed that median RT during monetary gain and loss interacted with sex to predict restriction at one-year.   

Overall, findings suggest that greater neural sensitivity to punishment is a potential risk factor for disordered eating pathology in young adolescents. The study supports a potential neural marker for disordered eating at baseline, and a behavioral marker for restriction at baseline and one-year for females. This information can aid in understanding the underlying mechanisms of disordered eating in order to identify resilience and risk factors in youth, and should therefore continue to be investigated.