Higher cardiovascular activation, but normal heartbeat-evoked potentials and cardiac interoceptive accuracy in somatoform disorders and major depressive disorder

in Psychiatry Research Communications (2022), 2(3), 100052

The perception-filter model posits that the generation of medically-unexplained symptoms is associated with (I.) more intense afferent bodily signals, (II.) impaired filter system activity to ... [more ▼]

The perception-filter model posits that the generation of medically-unexplained symptoms is associated with (I.) more intense afferent bodily signals, (II.) impaired filter system activity to differentiate relevant from irrelevant signals, and (III.) altered perception of bodily signals. We tested these assumptions for cardiac perception in patients with somatoform disorders (SFD), patients with major depressive disorder (MDD) and healthy control (HC) individuals. Heart rate (variability; HR/HRV) and blood pressure served as indicators of bodily signals (I.); heartbeat-evoked potentials (HEPs) assessed during a heartbeat counting task (HCT) and a distraction task indicated filter system activity (II.); interoceptive accuracy (IAc) in the HCT was interpreted as an index of perception (III.). All indicators were assessed before and after a socially-evaluated cold pressor stress task (SECPT) and a control intervention. SFD patients (n ​= ​24) showed higher average HR and diastolic blood pressure, as well as lower HRV than HC individuals (n ​= ​22), but there were no differences in HEPs or IAc. Neither were there significant differences between the SFD and the MDD groups (n ​= ​24), nor any stress effect on HEPs or IAc. Our findings suggest that increased intensity of bodily signals (I.) is the only model assumption that could be supported for patients with fully-developed SFD. [less ▲]

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

in International Journal of Eating Disorders (2021), 54(7), 1106-1115

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 ... [more ▼]

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, i.e. 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 non-caloric 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 bulimic patients. Power in the bradygastria range was greater in ED than in HC subjects. 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. [less ▲]

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

in Addictive Behaviors (2021), 113

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 ... [more ▼]

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. [less ▲]

Altered interoceptive awareness in high habitual symptom reporters and patients with somatoform disorders

in Frontiers in Psychology (2020), 11(1), 1859

Objective. Altered interoception may play a major role in the etiology of medically unexplained symptoms (MUS). It remains unclear, however, if these alterations concerns noticing of signals or if they ... [more ▼]

Objective. Altered interoception may play a major role in the etiology of medically unexplained symptoms (MUS). It remains unclear, however, if these alterations concerns 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: 486 individuals completed the Screening for Somatoform Disorders (SOMS-2). 32 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. [less ▲]

Erhöhte Reaktivität Herzschlag-evozierter Potenziale während der Aufmerksamkeits- fokussierung auf den eigenen Herzschlag und erhöhte kardiovaskuläre Aktivität bei Personen mit hoher somatoformer Symptombelastung

in Kirschbaum, C. (Ed.) 45. Jahrestagung Psychologie und Gehirn - Abstractband (2019)

Die psychobiologischen Mechanismen der Entstehung körperlicher Symptome bei somatoformen Störungen sind weitgehend unklar. Im Perception-Filter-Modell wird postuliert, dass (1.) verstärkte ... [more ▼]

Die psychobiologischen Mechanismen der Entstehung körperlicher Symptome bei somatoformen Störungen sind weitgehend unklar. Im Perception-Filter-Modell wird postuliert, dass (1.) verstärkte Signalübermittlung von Körperorganen und (2.) verringerte Filterfunktion im ZNS zu (3.) verstärkter Wahrnehmung von Symptomen führt. Bislang existiert jedoch keine Evidenz, die diesen Zusammenhang an einer von somatoformen Symptomen belasteten Population unterstützt. Um diesen Sachverhalt aufzudecken, wurden zunächst 486 Personen aus der Allgemeinbevölkerung anhand einer Online- Version des Screenings für Somatoforme Störungen (SOMS-2) anhand des oberen und unteren Centils in Personen mit hoher (HSB) und niedriger somatoformer Symptombelastung (NSB) geteilt. Jeweils 29 NSB- (21 Frauen; 26,0 J.) und HSBPersonen (27 Frauen; 28,4 J.) wurden im Labor anhand (1.) verstärkter Körpersignale hinsichtlich kardiovaskulärer Aktivität und Cortisol-Aufwachreaktion, sowie (2.) Filterfunktionen im ZNS hinsichtlich Herzschlag-evozierter Potentiale (HEPs) während der Durchführung eines Herzschlagwahrnehmungstests und während Ruhe untersucht. HEPs reflektieren die Repräsentation kardio-afferenter Signale im ZNS. Die HSB-Gruppe zeigte eine höhere Ruhe-Herzrate (72,7 vs. 66,8 bpm) und eine geringere Herzratenvariabilität (RMSSD: 36,8 vs. 52,5 ms) als die LSB-Gruppe. Außerdem zeigten die HSB-Personen bei der Aufmerksamkeitsfokussierung auf den eigenen Herzschlag eine höhere Reaktivität der HEP-Amplitude als die LSB-Personen. Es gab keine Gruppenunterschiede hinsichtlich der Cortisol-Aufwachreaktion. Die Ergebnisse belegen sowohl (1.) die verstärkte Signalübermittlung von Körperorganen, als auch (2.) verringerte Filterfunktionen bei Personen mit hoher somatoformer Symptombelastung. Dies spricht für die Gültigkeit des Perception-Filter-Modells. Die erhöhte HEP-Reaktivität bezüglich der Aufmerksamkeitsfokussierung auf Körperprozesse könnte einen Biomarker für Personen mit hohem Risiko für die Entwicklung von somatoformen Störungen darstellen. [less ▲]

Herzschlag-evozierte Potenziale bei Bulimia nervosa

in Kirschbaum, C. (Ed.) 45. Jahrestagung Psychologie und Gehirn - Abstractband (2019)

Die ursprüngliche Annahme, dass Essstörungspatient/innen unter einem umfassenden Defizit der interozeptiven Wahrnehmung leiden, wird inzwischen differenzierter betrachtet. Unterschiedliche Befunde ergeben ... [more ▼]

Die ursprüngliche Annahme, dass Essstörungspatient/innen unter einem umfassenden Defizit der interozeptiven Wahrnehmung leiden, wird inzwischen differenzierter betrachtet. Unterschiedliche Befunde ergeben sich je nach betrachtetem Organsystem (Herz, Magen), Verarbeitungsebene (neuronal, Selbstbericht) und Diagnose. Die bisherige Befundlage ist jedoch unübersichtlich und widersprüchlich. Für Bulimia nervosa (BN) wurde sowohl reduzierte, als auch unveränderte Herzschlagwahrnehmung berichtet. Mit dem vorliegenden Beitrag steuern wir weitere Ergebnisse zur Herzschlagwahr nehmung bei und ergänzen diese um einen physiologischen Indikator der kortikalen Verarbeitung kardio-afferenter Signale (Herzschlag-evozierte Potenziale, HEPs). Es wurden 22 Frauen mit akuter oder teilremittierter BN (BMI 23,94±3,61; Alter 31,86±11,20) und 22 gesunde Frauen untersucht (BMI 24,24±3,37; Alter 31,00±10,15). Die Stichproben wurden nach Alter und BMI parallelisiert. Die Teilnehmerinnen führten eine Herzschlagwahrnehmungsaufgabe nach Schandry durch, während ein 64-Kanal-EEG aufgezeichnet wurde. HEPs wurden als mittlere EEG-Amplitude von 455ms bis 595ms nach der R-Zacke berechnet. Die Ergebnisse zeigen keine signifikanten Gruppenunterschiede in Herzschlagwahrnehmung, HEPs und Herzrate. Dies bestätigt vorherige Befunde einer intakten Herzschlagwahrnehmung bei BN. Zusätzlich können wir von einer intakten kortikalen Verarbeitung kardio-afferenter Reize ausgehen. Die Wahrnehmung des Herzschlags ist insbesondere für die Verarbeitung und Regulation von Emotionen relevant. Auf Basis der vorliegenden und früheren Befunde ist davon auszugehen, dass defizitäre Emotionsregulation bei BN nicht auf veränderte Herzschlagwahrnehmung zurückzuführen ist. [less ▲]

Enhanced Cortical Processing of Cardio-Afferent Signals in Anorexia Nervosa

in Clinical Neurophysiology (2019), 130(9), 1620-1627

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 ... [more ▼]

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 Rpeak 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. [less ▲]

Mood, emotions and eating disorders

in Agras, W. Stewart; Robinson, Athena (Eds.) The Oxford Handbook of Eating Disorders, Second Edition (2018)

Mood and emotions are intrinsically involved with eating. This chapter discusses basic mechanisms, findings, and models that help our understanding of the interactions between eating and emotions, in both ... [more ▼]

Mood and emotions are intrinsically involved with eating. This chapter discusses basic mechanisms, findings, and models that help our understanding of the interactions between eating and emotions, in both clinical and nonclinical populations. The finding that negative affect predicts EDs transdiagnostically, and that comorbidity with depressive disorders and anxiety disorders is the norm among patients with EDs suggests that EDs may not necessarily be restricted to domains of eating behavior and body image but may also be associated with significant difficulties in affective functioning. This chapter reviews the evidence relating to the notion that EDs are disturbances of mood regulation, in which regulatory strategies specifically related to eating and the body are used to diminish negative affect associated with food, body image, or stress. [less ▲]

Impaired filter function in patients with somatoform disorders and major depression, as reflected by auditory evoked potentials in an oddball and an active distraction paradigm

in Abstractband Psychologie und Gehirn 2018 (2018)

Introduction: In the in influential perception-filter model of somatoform disorders (SD), three stages of symptom perception are postulated: (1) bodily signals, which may be amplified by stress, (2) a ... [more ▼]

Introduction: In the in influential perception-filter model of somatoform disorders (SD), three stages of symptom perception are postulated: (1) bodily signals, which may be amplified by stress, (2) a filter system, which distinguishes between relevant and irrelevant stimuli, and (3) cortical perception of physical symptoms. As there is dearth of evidence so far supporting the relationship between (1) bodily signals and (2) filter processes in SD, this study investigated if filter processes are altered in SD and if stress may affect filter mechanisms. Methods: Twenty-four patients with SD, 24 with depression and 24 healthy control individuals were assessed. Event-related potentials (ERPs) with two different auditory distraction procedures were recorded over four blocks, one before and three after either a socially evaluated cold pressor test (SECPT) or a control procedure. We manipulated both the frequency of and the attentional focus on stimuli to reflect filter processes. Results: We found smaller P3b amplitudes (reflecting memory storage) in patients with depression and SD, as compared to healthy controls. Furthermore, both patient groups showed a smaller P3a amplitude (reflecting attention), when counting the infrequent tone ("Oddball task") and a smaller N1 amplitude when counting the frequent tone ("active distraction"). In patients with SD, the SECPT had a decreasing effect on P3a amplitudes. Conclusions: Both late filter processes, reflecting attention (P3a) and memory storage (P3b), may be impaired in SD and depression. As acute stress affected attention in SD patients only, the impact of bodily signals (1) on filter processes (2) may be specific for SD. [less ▲]

Affective evaluation of body images in anorexia nervosa

in Psychophysiology (2017), 54(S1),

Anorexia nervosa is characterized by fear of weight gain. This is reflected in amygdala activation during confrontation with distorted photographs of oneself simulating weight gain. In contrast ... [more ▼]

Anorexia nervosa is characterized by fear of weight gain. This is reflected in amygdala activation during confrontation with distorted photographs of oneself simulating weight gain. In contrast, photographs of emaciated women induce startle attenuation, suggesting a positive valuation of extreme slimness. To combine these findings, we applied an affective startle modulation paradigm containing photos of the participants simulating weight gain and photos simulating weight loss. We assessed eye-blink startle responses via EMG in 20 women with anorexia nervosa (AN; mean age = 25 years; mean BMI = 23) and 20 healthy control women (HC; mean age = 25 years; mean BMI = 23). We were able to replicate affective startle modulation of standard positive, negative, and neutral pictures, except for an absence of startle attenuation for positive pictures in AN. Body images did not modulate the startle response in either group. This was in contrast to the subjective ratings, in which the AN group indicated negative valence and high arousal for distorted body images. The body photographs used in our study emphasized general body shape and it appears that this was not threatening to AN patients. Photos highlighting body details might produce different results. Considering that body image exposure, a frequently used intervention tool for AN, aims at fear reduction through habituation, it is essential to determine which aspects of the body actually elicit fear responses to maximize therapy outcome. [less ▲]