Abnormal sense of agency in eating disorders

Abstract

The feeling of controlling one’s own actions and, through them, impacting the external environment (i.e. Sense of Agency—SoA) can be relevant in the eating disorders (EDs) symptomatology. Yet, it has been poorly investigated. This study aims to implicitly assess SoA exploiting the Sensory Attenuation paradigm in two groups of EDs patients (Anorexia Nervosa Restrictive and Anorexia Nervosa Binge-Purging or Bulimia Nervosa) compared to a control group. We find that controls perceive self-generated stimuli as less intense than other-generated ones showing the classic pattern of sensory attenuation. By contrast, EDs patients show the opposite pattern, with self-generated perceived as more intense than other-generated stimuli. This result indicates an alteration of the implicit component of the feeling of control in EDs patients, thus suggesting a potential implication of these results for the clinical practice and the treatment of EDs symptomatology.

Are you how you eat? Aspects of self-awareness in eating disorders

“…The sense of agency can be measured in experimental settings by asking participants to explicitly judge whether their action caused an outcome event, or by using implicit measures, such as the compression of perceived time between action and outcome (Haggard, 2017). Thus, one can evaluate the concept of agency based on the degree to which a person believes they can impact their target experiences and behaviors (Colle et al, 2023). For instance, a patient's sense of agency regarding symptoms of bulimia nervosa can be assessed concurrently with treatment (Kristmannsdottir et al, 2019).…”

“…This difference in perception gives rise to the so-called sensory attenuation phenomenon, in which the intensity of self-generated stimuli is perceived as significantly attenuated compared to the same stimuli generated by someone else. This phenomenon occurs because people automatically anticipate the sensory consequences of self-generated actions, explaining why people are unable to tickle themselves (Colle et al, 2023). Particularly, the first studies in this area show that in ED patients, there is an opposite pattern of behavior, with self-generated stimuli perceived as more intense than other-generated stimuli.…”

“…Particularly, the first studies in this area show that in ED patients, there is an opposite pattern of behavior, with self-generated stimuli perceived as more intense than other-generated stimuli. This result indicates an alteration of the implicit component of the feeling of control in ED patients and alterations in the sense of agency (Colle et al, 2023).…”

“…When AN patients experience a stronger sense of ownership over the rubber hand than healthy individuals (Keizer et al, 2014), we can begin to understand not only the intensity of the feeling of agency but also its accuracy. In this case, AN patients seem to have a false yet robust sense of agency (Colle et al, 2023).…”

“…Patients with this diagnosis often perceive their symptoms as a solution to their problems (Kristmannsdottir et al, 2019; Bruch, 1973). Therefore, anorexic patients show a false yet powerful sense of agency (Colle et al, 2023). Conversely, individuals within the bulimic spectrum may experience a loss of control during compulsive episodes.…”