Development and initial validation of a self-report measure to assess eating disorder-specific interoceptive perception.

Interoceptive deficits-particularly with respect to the perception of emotions, hunger, and satiety-constitute important targets for intervention in eating disorders (EDs). Suitable self-report measures to identify these deficits, however, are lacking. We, therefore, developed and validated a multidimensional questionnaire to assess eating disorder-specific interoceptive perception (EDIP) in terms of the ability to perceive and discriminate between emotions, hunger, and satiety. In two independent samples with a total of 2058 individuals (22.74% with self-reported EDs), exploratory and confirmatory factor analyses revealed a four-factor solution of the EDIP Questionnaire (EDIP-Q) with the subscales Emotions, Hunger, Satiety, and Discrimination. The EDIP-Q has sound psychometric properties and was related to convergent questionnaires but unrelated to divergent self-report measures, supporting its construct validity. Participants with self-reported EDs had significantly lower EDIP-Q scores compared to participants without self-reported ED diagnosis. While individuals with self-reported anorexia nervosa (AN), bulimia nervosa (BN), and binge-eating disorder (BED) report similar difficulties in perceiving emotions, participants with BN and BED report greater difficulties in perceiving satiety and differentiating between hunger and emotional states compared to participants with AN. In contrast, individuals with AN report higher sensibility to satiety but lower sensibility to hunger compared to individuals with BN and BED. The EDIP-Q is a valuable clinical tool to establish profiles of deficits in EDIP that provide the basis for developing more targeted treatment approaches for EDs. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Gastric interoception and gastric myoelectrical activity in bulimia nervosa and binge-eating disorder.

OBJECTIVE: Identifying factors that control food intake is crucial to the understanding and treatment of eating disorders characterized by binge eating. In healthy individuals, stomach distension plays an important role in the development of satiation, but gastric sensations might be overridden in binge eating. The present study investigated the perception of gastric signals (i.e., gastric interoception) and gastric motility in patients experiencing binge-eating episodes, that is, bulimia nervosa (BN) and binge-eating disorder (BED). METHOD: Twenty-nine patients with BN or BED (ED group) and 32 age-, sex-, and BMI-matched healthy controls (HC group) participated in the study. The onset of satiation and stomach fullness were assessed using a novel 2-step water load test (WLT-II). Gastric myoelectrical activity (GMA) was measured by electrogastrography (EGG) before and after ingestion of noncaloric water. RESULTS: Individuals in the ED group drank significantly more water until reporting satiation during the WLT-II. The percentage of normal gastric myoelectrical power was significantly smaller in the ED group compared to HC, and negatively related to the number of objective binge-eating episodes per week in patients with BN or BED. Power in the bradygastria range was greater in ED than in HC participants. DISCUSSION: Patients with EDs have a delayed response to satiation compared to HC participants, together with abnormal GMA. Repeated binge-eating episodes may induce disturbances to gastric motor function.

Mood-induced changes in the cortical processing of food images in bulimia nervosa.

BACKGROUND: Negative mood often triggers binge eating in bulimia nervosa (BN). We investigated motivational salience as a possible underlying mechanism using event-related potentials (ERPs) as indicators of motivated attention allocation (P300) and sustained processing (LPP). METHODS: We collected ERPs (P300: 350-400 ms; LPP: 600-1000 ms) from 21 women with full-syndrome or partially remitted BN and 21 healthy women (HC), matched for age and body mass index. Idiosyncratic negative and neutral situations were used to induce corresponding mood states (counterbalanced), before participants viewed images of high- and low-calorie foods and neutral objects, and provided ratings for pleasantness and desire to eat. RESULTS: P300 was larger for foods than objects; LPP was largest for high-calorie foods, followed by low-calorie foods, then objects. The BN group showed an increased desire to eat high-calorie foods under negative mood and stronger mood induction effects on ERPs than the HC group, with generally reduced P300 and a small increase in LPP for high-calorie foods. Effects were limited to circumscribed electrode positions. Exploratory analyses showed clearer effects when comparing high vs. low emotional eaters. CONCLUSION: We argue that negative mood decreased the availability of cognitive resources (decreased P300) in BN, thereby facilitating disinhibition and food cravings (increased desire-to-eat ratings). Increased sustained processing might be linked to emotional eating tendencies rather than BN pathology per se, and reflect approach motivation, conflict, or regulatory processes. Negative mood appears to induce complex changes in food image processing, whose understanding may contribute to the development of tailored interventions in the future.

Distinctive body perception mechanisms in high versus low symptom reporters: A neurophysiological model for medically-unexplained symptoms.

OBJECTIVE: The neurophysiological processes involved in the generation of medically-unexplained symptoms (MUS) remain unclear. This study tested three assumptions of the perception-filter model contributing to MUS: (I.) increased bodily signal strength (II.) decreased filter function, (III.) increased perception. METHODS: In this cross-sectional, observational study, trait MUS were assessed by a web-based survey (N = 486). The upper and lower decile were identified as extreme groups of high (HSR; n = 29; 26 women; Mage = 26.0 years) and low symptom reporters (LSR; n = 29; 21 women; Mage = 28.4 years). Mean heart rate (HR) and heart rate variability (HRV), and cortisol awakening response (CAR) were assessed as indicators of bodily signal strength (I.). Heartbeat-evoked potentials (HEPs) were assessed during rest and a heartbeat perception task. HEPs reflect attentional resources allocated towards heartbeats and served as index of filter function (II.). Interoceptive accuracy (IAc) in heartbeat perception was assessed as an indicator of perception (III.). RESULTS: HSR showed higher HR and lower HRV (RMSSD) than LSR (I.), but no differences in CAR. HSR exhibited a stronger increase of HEPs when attention was focused on heartbeats than LSR (II.); there were no group differences in IAc (III.). CONCLUSIONS: The perception-filter model was partially confirmed in that HSR showed altered bodily signals suggesting higher sympathetic activity (I.); higher HEP increases indicated increased filter function for bodily signals (II.). As more attentional resources are mobilized to process heartbeats, but perception accuracy remains unchanged (III.), this overflow could be responsible for detecting minor bodily changes associated with MUS.

Altered Interoceptive Awareness in High Habitual Symptom Reporters and Patients With Somatoform Disorders.

Objective: Altered interoception may play a major role in the etiology of medically unexplained symptoms (MUS). It remains unclear, however, if these alterations concern noticing of signals or if they are limited to the interpretation of signals. We investigated whether individuals with MUS differ in interoceptive awareness as assessed with the Multidimensional Assessment of Interoceptive Awareness (MAIA) questionnaire. Methods: Study 1: A total of 486 individuals completed the Screening for Somatoform Disorders (SOMS-2). Thirty-two individuals each of the upper and lower decile of the SOMS distribution (low symptom reporters/LSR, high symptom reporters/HSR) completed the MAIA. Study 2: MAIA scores of individuals diagnosed with somatoform disorder (SFD; n = 26) were compared to individuals with major depressive disorder (MDD; n = 25) and healthy controls (HC; n = 26). Results: HSR had lower scores than LSR on the MAIA scales Not-Distracting and Not-Worrying. The SFD and MDD groups showed lower scores than HC on the MAIA scales Not-Distracting, Self-Regulation, and Trusting. The MDD group scored lower than the other two groups on the scales Body Listening and Attention Regulation. There were no group differences on the scale Noticing. Conclusion: HSR, SFD, and MDD patients do not differ from HC in the awareness of noticing of interoceptive signal processing, whereas cognitive facets of interoception, such as distraction or self-regulation are differentially affected. This highlights the necessity of including specifically targeted interventions, which improve interoceptive awareness, in the prevention and treatment of SFDs.

Fight, Flight, - Or Grab a Bite! Trait Emotional and Restrained Eating Style Predicts Food Cue Responding Under Negative Emotions.

In today's society, obesity rates are rising as food intake is no longer only a response to physiological hunger signals that ensure survival. Eating can represent a reward, a response to boredom, or stress reduction and emotion regulation. While most people decrease food intake in response to stress or negative emotions, some do the opposite. Yet, it is unclear who shows emotional overeating under which circumstances. Emotion regulation theories describe emotional overeating as a learned strategy to down-regulate negative emotions. Cognitive theories, by contrast, attribute emotional overeating to perceived diet breaches in individuals who chronically attempt to diet. After consuming "forbidden foods", they eat more than individuals who do not restrict their food intake. This laboratory study investigated emotional overeating by exposing individuals to a personalized emotion induction while showing images of palatable foods. Outcome variables indexed cue reactivity to food images through picture ratings (valence, desire to eat), facial expressions (electromyography of the corrugator supercilii muscle), and brain reactivity by detecting event-related potentials (ERPs) by means of electroencephalography (EEG). The influence of emotion condition (negative, neutral) and individual differences (self-reported trait emotional and restrained eating) on outcome variables was assessed. Valence ratings and appetitive reactions of the corrugator muscle to food pictures showed a relative increase in the negative condition for individuals with higher emotional eating scores, with the opposite pattern in lower scores. Desire to eat ratings showed a similar pattern in individuals who showed a strong response to the emotion induction manipulation, indicative of a dose-response relationship. Although no differences between conditions were found for ratings or corrugator activity with restrained eating as a predictor, an ERP at P300 showed increased activation when viewing food compared to objects in the negative condition. Findings support emotion regulation theories: Emotional eaters showed an appetitive reaction in rating patterns and corrugator activity. EEG findings (increased P300) suggest a motivated attention toward food in restrained eaters, which supports cognitive theories. However, this did not translate to other variables, which might demonstrate successful restraint. Future studies may follow up on these findings by investigating eating disorders with emotion regulation difficulties.

Enhanced cortical processing of cardio-afferent signals in anorexia nervosa.

OBJECTIVE: To assess cardiac interoception in anorexia nervosa (AN) using a multidimensional approach. METHODS: We assessed the physiological dimensions of cardioception, i.e. the peripheral signal itself (heart rate, HR, and heart rate variability, HRV) and its cortical representation (heartbeat evoked potentials, HEPs), and the psychological dimensions of interoceptive accuracy (heartbeat perception) and interoceptive sensibility (confidence ratings). Electroencephalogram (EEG) and electrocardiogram (ECG) were recorded concurrently during rest and while performing a heartbeat perception task in a sample of 19 female in-patients with AN (DSM-5) and 19 healthy control women (HC). RESULTS: HEPs, defined as mean EEG amplitude in a time window of 455-595 ms after the R-peak of the ECG, were significantly larger in the AN than in the HC group across conditions (p = .002, d = 1.06). There was a trend toward better heartbeat perception in AN, but no group differences in HR, HRV, and confidence ratings. CONCLUSIONS: Individuals with AN showed an interoceptive profile of heightened cortical processing, a trend toward heightened interoceptive accuracy, and unaltered cardiac autonomic activation and interoceptive sensibility. SIGNIFICANCE: In terms of neurobiological models of AN, enhanced cortical representations of interoceptive signals might reflect a mechanism, which promotes fasting by alleviating negative body states.

Gastric modulation of startle eye blink.

Previous assessment methods of gastric interoception either rely on self-reports, or imply invasive procedures. We investigated the reliability of startle methodology as a non-invasive alternative for the assessment of afferent gastric signals. Twenty-four participants were tested on three separate days, on which they were requested to ingest water (either 0, 300 or 600ml), after 8h of fasting. On each assessment day, eye blink responses (EMG) to 10 acoustic startle stimuli (105dB) were assessed at 4 measurement points (before, 0, 7, 14min. after ingestion). Increased normogastric responses (EGG), ratings of satiety and fullness, and higher heart rate variability (RMSSD) suggested effective non-invasive induction of gastric distention. Startle responses were lower directly after ingestion of 600ml as compared to earlier and later measurements. These results suggest that startle methodology provides a reliable method to investigate afferent gastric signals. It could be useful to study possible dissociations between subjective reports and objective afferent gastric signals in eating or somatoform disorders.

The Water Load Test As a Measure of Gastric Interoception: Development of a Two-Stage Protocol and Application to a Healthy Female Population.

The sensitivity for one's own internal body signals (i.e., interoception) has been demonstrated to play an important role in the pathogenesis of eating and weight disorders. Most previous measures assessing interoceptive processing have not, or only partly, captured perception of hunger and satiety cues, which is a core aspect of interoceptive deficits in eating disorders. In addition, methods used to measure sensitivity to gastric signals are heterogeneous and findings inconsistent. The primary aim of the present study was to establish a standardised test to measure gastric interoception, and to provide normative data using a non-clinical adult sample. The two-step Water Load Test (WLT-II) involves ingestion of non-caloric water until perceived satiation (step 1) and until maximum fullness (step 2). The WLT-II consists of several variables: Besides volumes of water ingested until satiation and maximum fullness expressed in ml, percentage of satiation to maximum fullness is calculated as an individual index of gastric interoception that is not confounded with stomach capacity. Ninety-nine healthy women participated in the study. Measures included the WLT-II, the heartbeat tracking test, a self-report questionnaire assessing subjective sensations, and the Eating Disorder Inventory-2. Twenty-eight participants underwent test-retest of the WLT-II. Results suggest that the WLT-II is a valid and reliable measure of gastric interoception. Importantly, satiation volume and percentage of satiation to maximum fullness were strongly positively related to self-reported bulimic symptoms, indicating that the WLT-II could emerge as a useful clinical tool to measure interoceptive processing in the field of eating disorders.

Food-cue affected motor response inhibition and self-reported dieting success: a pictorial affective shifting task.

Behavioral inhibition is one of the basic facets of executive functioning and is closely related to self-regulation. Impulsive reactions, that is, low inhibitory control, have been associated with higher body mass index (BMI), binge eating, and other problem behaviors (e.g., substance abuse, pathological gambling, etc.). Nevertheless, studies which investigated the direct influence of food-cues on behavioral inhibition have been fairly inconsistent. In the current studies, we investigated food-cue affected behavioral inhibition in young women. For this purpose, we used a go/no-go task with pictorial food and neutral stimuli in which stimulus-response mapping is reversed after every other block (affective shifting task). In study 1, hungry participants showed faster reaction times to and omitted fewer food than neutral targets. Low dieting success and higher BMI were associated with behavioral disinhibition in food relative to neutral blocks. In study 2, both hungry and satiated individuals were investigated. Satiation did not influence overall task performance, but modulated associations of task performance with dieting success and self-reported impulsivity. When satiated, increased food craving during the task was associated with low dieting success, possibly indicating a preload-disinhibition effect following food intake. Food-cues elicited automatic action and approach tendencies regardless of dieting success, self-reported impulsivity, or current hunger levels. Yet, associations between dieting success, impulsivity, and behavioral food-cue responses were modulated by hunger and satiation. Future research investigating clinical samples and including other salient non-food stimuli as control category is warranted.

Impulsive reactions to food-cues predict subsequent food craving.

Low inhibitory control has been associated with overeating and addictive behaviors. Inhibitory control can modulate cue-elicited craving in social or alcohol-dependent drinkers, and trait impulsivity may also play a role in food-cue reactivity. The current study investigated food-cue affected response inhibition and its relationship to food craving using a stop-signal task with pictures of food and neutral stimuli. Participants responded slower to food pictures as compared to neutral pictures. Reaction times in response to food pictures positively predicted scores on the Food Cravings Questionnaire - State (FCQ-S) after the task and particularly scores on its hunger subscale. Lower inhibitory performance in response to food pictures predicted higher FCQ-S scores and particularly those related to a desire for food and lack of control over consumption. Task performance was unrelated to current dieting or other measures of habitual eating behaviors. Results support models on interactive effects of top-down inhibitory control processes and bottom-up hedonic signals in the self-regulation of eating behavior, such that low inhibitory control specifically in response to appetitive stimuli is associated with increased craving, which may ultimately result in overeating.