PhD Talks: Mechanisms of Mental Health

Event details

Speaker(s): Charlotte Aynsworth, Lucy Stafford, Jiayu Liu

1. Interoceptive dysfunction is central to eating disorders, and emerging evidence indicates that the maladaptive appraisal of gastrointestinal signals predicts pathology better than body-general interoception. However, existing tools do not adequately measure this construct; they conflate sensation intensity with appraisal and assess a limited range of emotional responses, likely due to little input from eating disorder populations during tool development. To address this gap, we developed and validated the Negative Appraisal of Gastric Sensations (NAGS) scale to specifically capture the affective interpretation of hunger and fullness. Exploratory factor analysis (sample 1 n=337, 80.12% Female, 75.97% White British) and confirmatory factor analysis (sample 2 n=337, 85.16% Female, 79.23% White British) supported a two-factor scale: hunger-fear and fullness-shame. The scale demonstrated robust psychometric properties, including strong internal and test-retest reliability, as well as criterion, concurrent, convergent, and discriminant validity. The subscales successfully distinguished eating disorder from gastrointestinal disorder and non-disordered controls, and this was not attributable to differential item functioning. Exploratory analyses using latent profile analysis and hierarchical regressions supported this measure’s utility as a critical interoceptive factor in eating disorders over and above existing interoceptive measures: increases in fullness-shame predicted higher overall symptom severity, body dissatisfaction, and purge-dominant category membership, while increases in hunger-fear specifically predicted restriction-dominant category membership. As such, the scale could be considered a useful tool for researchers studying the somatic experience of eating disorders, but also primary care physicians for distinguishing primary gastrointestinal disorders from eating disorders presenting as gastrointestinal complaints.
3. Active forgetting plays a crucial role in shaping memories of the past. Retrieval-induced forgetting(RIF), where retrieving certain memories(targets) reduces accessibility of related unretrieved memories(competitors), has been studied with emotional materials, yet it remains unclear how RIF operates when targets and competitors have distinct emotional properties within the same memory. We investigated this across three preregistered experiments using the retrieval practice paradigm, in which participants studied category-exemplar pairs of varying emotional valence, practised retrieving a subset, then completed test. Experiment 1 showed that retrieving negative targets impaired recall of positive competitors, but not vice versa, suggesting stronger interference from negative targets or stronger inhibition of positive competitors. Experiment 2 introduced neutral stimuli to dissociate these explanations: RIF occurred for negative targets with neutral competitors but not for neutral targets with positive competitors, supporting the interference account. Experiments 1 and 2 indicated RIF is more likely when targets are emotionally salient than competitors. Experiment 3 further tested this: neither neutral targets with negative competitors nor positive targets with neutral competitors showed RIF. Exploratory analyses suggested emotional distance between items may explain this result. These findings implicate interference may contribute to RIF when targets and competitors have distinct emotional properties.