A Multi-Modal Assessment of Fear Conditioning in Adolescent Anorexia Nervosa

Background: Anorexia nervosa (AN) is a pernicious psychiatric disorder which is principally characterized by a fear of weight gain. Notwithstanding the centrality of fear in the psychopathology of AN, controlled assessments of negative valence systems are lacking. Herein we investigate whether deficits in either fear acquisition or fear extinction are evident among adolescent females with AN. Methods: Adolescent girls (Mage = 14.6 years) with DSM-5 diagnoses of AN (N=25) and age-matched control girls (Mage = 14.8 years) with no DSM-5 diagnoses (N=25) completed structured clinical interviews and participated in a classical three-phase Pavlovian fear conditioning paradigm. Skin conductance response (SCR) was measured, alongside self-reported fear, valence and fear expectancy ratings. Results: Both groups demonstrated significant differential acquisition across all four measures. Regarding group comparisons, no differences emerged for self-reported fear, valence and fear expectancy ratings during acquisition, although for SCR, those with AN demonstrated reduced physiological arousal relative to controls. Both groups demonstrated significant differential extinction for US expectancy, self-report fear, and self-report valence. No statistically significant group differences were evident during extinction to the CS+, on any outcome measure. However, controls reported more positive valence to the CS- than those with AN. Conclusions: Contrary to our hypotheses we did not find support for elevated fear responding among adolescent girls with AN with regards to fear acquisition or extinction. These data do not support the notion that elevated fear acquisition underpins AN psychopathology, but suggest that exposure treatments may be helpful, since extinction learning is intact in AN.