Altered interoceptive awareness in anorexia nervosa: Effects of meal anticipation, consumption and bodily arousal

Abstract

Objective Impaired interoceptive awareness (IA), the subjective perception of internal body sensations, has been proposed as a vulnerability or maintaining factor in anorexia nervosa (AN). We examined whether IA of heartbeat and breathing sensations was impaired in AN across a range of arousal levels, and whether it was influenced by meal anticipation and consumption. Method IA was assessed using randomized, double-blinded, bolus intravenous infusions of isoproterenol, a peripheral beta-adrenergic sympathetic agonist, and saline. Fifteen women with AN and 15 age-, and sex- matched healthy comparisons were evaluated before and after consumption of a 1000 Calorie meal. During each infusion participants rated their moment-to-moment intensity of heartbeat and breathing sensations with a dial. To measure IA we evaluated interoceptive detection thresholds, retrospective ratings of palpitation and dyspnea intensity, and interoceptive accuracy via correlations between subjective dial ratings and observed heart rate responses. Results Contrary to prediction the AN group was more likely to report detection of interoceptive sensations across all conditions, an effect driven by false discriminations at low arousal levels. Concordant with prediction, meal anticipation was associated with intensified interoceptive sensations, particularly dyspnea. There were no differences in interoceptive accuracy. Discussion This represents the first demonstration of interoceptive prediction errors in AN. Although IA is unimpaired at high arousal levels in AN, prediction signals are abnormal at low arousal levels, especially during meal anticipation. Altered interoceptive prediction signaling during meal anticipation could contribute to phenotypes of high anxiety in AN or alternatively, might be explained by enhanced meal associated anxiety.

Taste sensitivity in anorexia nervosa: A systematic review

“…Moreover, these findings indicate a potential conflict between self‐perceived (heightened) and actual (lowered) sensitivity to taste stimuli that closely resembles sensory prediction errors documented in AN in the field of interoceptive processing: individuals with AN appear to self‐report heightened levels of interoceptive sensitivity, whilst in fact exhibiting lower sensitivity on experimental measures (Khalsa et al, 2015; Khalsa & Lapidus, 2016). These interoceptive prediction errors have been associated with heightened anxiety and can act as a potent motivation to avoid the triggering stimulus‐ such as food or tastes (Kaye et al, 2004; Paulus & Stein, 2010).…”

Panic Anxiety in Humans with Bilateral Amygdala Lesions: Pharmacological Induction via Cardiorespiratory Interoceptive Pathways

“…After each infusion period, participants retrospectively rated their experience of heartbeat and breathing sensations. This approach is identical to our previous studies of cardiorespiratory interoception in healthy individuals (Khalsa et al, 2009b), brain injured individuals (Khalsa et al, 2009a), and individuals with anorexia nervosa (Khalsa et al, 2015).…”

“…First, its peripheral mechanism of action (Murphy and Johanson, 1985;Borges et al, 1999) provides a potent probe of afferent interoceptive processing (Khalsa et al, 2009b). Second, this approach likely bypasses chemosensory pathways stimulated by CO 2 inhalation (Maddock and Carter, 1991) and lactate infusion (Liebowitz et al, 1984;Maddock et al, 2013).…”

“…We assessed numerous facets of interoception (Khalsa et al, 2015). We determined interoceptive detection thresholds by dichotomizing dial ratings using custom MATLAB scripts.…”

“…Based on our previous research using isoproterenol (Khalsa et al, 2009a), we predicted that individuals with focal bilateral amygdala damage might also demonstrate impaired cardiorespiratory interoception.…”