Disentangling Emotional Processing From Regulation in Bulimia Nervosa

Relevance:

Over 1.6 million people in the UK are affected by an eating disorder and approximately 40% of these - 640,000 - suffer from bulimia nervosa (BN). Research shows that at 10 years after diagnosis, only about half the people with BN will have recovered fully, demonstrating the importance of developing new and more effective treatment. A recently published study suggests that training emotion regulation skills may work as an alternative treatment. This is because difficulties with emotions have been shown to contribute to eating disorder pathologies. However, most studies looking at emotional difficulties in this population have used self-report methods, despite the fact that high levels of alexithymia (difficulties with identifying and describing emotions) characterise this population, indicating that these findings are potentially flawed. In addition, self-report data show that two processes seem involved in eating disorders, namely emotional intensity and emotional dysregulation. However, experiencing emotions with higher intensity also makes it harder to reappraise emotions so it is not clear whether individuals with BN actually have a real deficit in emotion regulation, because self-reports cannot distinguish the two. The current project is proposing to use an objective way to disentangle these aspects of emotional processing by looking at two brain activities. The first is called the N1 because it appears about 100 ms after the presentation of a stimulus and is of negative amplitude; the second is called the LPP for Late Positive Potential.

This proposal also aims to investigate the mechanisms behind the observed link between negative urgency (acting impulsively under distress) and binge eating by exploring the brain's ability to filter out irrelevant stimuli in the environment -also called sensory gating. Whilst individuals are constantly being stimulated by information, the brain usually filters irrelevant information to prevent the cortex from being overloaded. However, if too much attention is directed towards a stimulus (such as a negative event or food stimuli), sensory gating deficits may occur, which could lead to cognitive deficits such as negative urgency. In a previous study, the investigators have shown impaired sensory gating in bipolar disorders and due to similarities in affective processing between bipolar disorder and BN as well as high comorbidity between these disorders, the investigators suggest similar mechanisms may be in place in BN.

This project has strong implications for treatment, because different approaches could be used depending on what processes are affected (e.g. training to reallocate attention vs helping with emotion regulation strategies).

Research Questions: