All workshops are included with your registration fee for the virtual meeting. Pre-registration is not required but highly encouraged. There is no fee to attend a workshop.
Innovative Treatment Approaches
Chairs: Anja Hilbert, Ulrike Schmidt, Daniel Le Grange, and Katrin Giel
Thursday, October 15, 2020, 9AM – 12PM CT
New approaches to the treatment of eating disorders are needed to enhance efficacy and scope. In this workshop, selected areas of innovative treatment approaches will be introduced and illustrated with brief presentations, in order to stipulate discussion and networking. As an example of Technology-supported treatment, Bianka Vollert (Germany) will present on bridging the waiting time of patients with bulimia nervosa and binge-eating disorder by using a web-based intervention. José Gutiérrez Maldonado (Spain) will present on new developments in Virtual reality for the treatment of eating disorders, specifically anorexia nervosa, including virtual reality-based body exposure therapy, the use of avatars, and embodiment procedures. Advances in neuroscience have enriched our understanding of underlying neurocircuitry in eating disorders and inform the development of Brain-directed interventions such as neuromodulation; Bethan Dalton (UK) will present on repetitive transcranial magnetic stimulation for chronic anorexia nervosa. Combination treatments may represent an approach to optimize efficacy for eating disorders and comorbid disorders. Philippa Hay (Australia) will speak about the combination of interventions for obesity targeting weight loss and eating disorders. An under-researched area is the Treatment of feeding and eating disorders in children and adolescents. Jennifer Thomas (USA) will present on cognitive-behavioral therapy for avoidant/restrictive food intake disorder in children and adolescents as well as adults.
Neurosciences and Cognition
Instructors: Walter Kaye (Chair), Angela Favaro (Co-Chair), Stefan Ehrlich (Co-Chair), Laura Berner, Enrico Collantoni, Friederike Tam
Thursday, October 15th - 11:00 AM - 2:00 PM CT
New insights into anxiety and restricted eating in anorexia nervosa: Dorsal caudate dopamine metabolism and initiation of eating
Walter H Kaye MD, Christina E Wierenga PhD, Amanda Bischoff-Grethe PhD, Laura A Berner PhD, Alice V Ely PhD, Ursula F Bailer MD, Martin P Paulus MD, Julie L Fudge MD. University of California, San Diego
Background: In healthy humans, hunger is dysphoric and increases reward salience and subjective value of food to drive consumption. In contrast, individuals with anorexia nervosa (AN) often describe eating as anxiogenic, and food refusal may reduce dysphoric mood. Moreover, anxiety is a vulnerability for developing AN and is associated with poor outcome. How do we understand how anxiety plays a powerful role in restricted eating?
Methods: At two counterbalanced visits, one after a 16-hour fast and one after a standardized meal, 26 women remitted from AN (RAN; to avoid the confounding effects of malnutrition) and 22 matched control women (CW) received tastes of sucrose and water while functional MRI data were acquired.
Results: RAN with high harm avoidance (a mixture of anxiety, inhibition, and inflexibility) showed less activation in response to palatable taste when hungry in the rostral caudate.
Discussion: High harm avoidance was associated with reduced engagement of striatal associative control circuitry that translate food reward to motivated eating. Studies have found altered striatal DA metabolism in AN, and dorsal striatum function measured by BOLD response or DA metabolism has been linked to elevated anxiety, harm avoidance, and sensitivity to punishment in AN, healthy humans, and rodents. DA-depleted mice do not initiate feeding behavior, but will resume normal eating after restoration of DA selectively in the dorsal striatum, but not the ventral striatum. Dorsal striatum DA signaling may serve as a permissive, “action initiation” signal, promoting nutritive food retrieval and consumption in response to metabolic demand. Thus, a lower dorsal striatum response to taste when hungry among RAN participants with the most pronounced anxiety and/or behavioral inhibition may reflect a reduced eating action initiation signal. Recent findings for olanzapine and aripiprazole support investigation of medications targeting the dopamine system to improve eating behavior and reduce anxiety in AN.
Using computational cognitive neuroscience to understand bulimic symptoms
Laura A. Berner, Katia Harlé, Alan N. Simmons, Christina E. Wierenga, Amanda Bischoff-Grethe, Ursula F. Bailer, Martin Paulus, Walter H. Kaye
Introduction: Bulimia nervosa (BN) is associated with trait impulsivity and poor self-control. However, most individuals with BN engage in out-of-control binge-eating and purging behaviors that alternate with prolonged periods of rigidly restricted intake. It is unclear whether inhibitory control is particularly impaired after fasting, potentially increasing vulnerability to binge eating initiation, or after eating has started, potentially contributing to difficulty stopping eating and subsequent out-of-control purging behaviors, like self-induced vomiting.
Methods: To begin to test this question and identify the dynamic neurocognitive processes that might underlie bulimic symptoms, we conducted a secondary model-based analysis of fMRI data collected from healthy control women (CW, n = 21) and women remitted from BN (n = 22) scanned after acute periods of fasting and eating. Participants performed a parametric Stop Signal Task during fMRI on two counterbalanced visits—once after a 16-hour fast and once after a standard meal. A Bayesian dynamic belief model was used to estimate trial-by-trial expectations of the need to inhibit responding, or “p(stop).” A whole-brain Group x Visit linear mixed effects model examined group differences in the influence of fasting and eating on Bayesian unsigned prediction errors (UPE; the absolute difference between the actual need to stop and p(stop) on each trial; voxelwise p<0.001, clusterwise alpha=0.05). Regressions examined associations of UPE signal with past bulimic symptoms.
Results: The neural signal associated with UPE in the left dorsal caudate was abnormally modulated by state in the RBN group compared with CW, such that RBN women showed blunted UPE-dependent activation after eating. This reduced activation in the fed state was associated with more frequent past binge eating and self-induced vomiting.
Conclusions: Findings suggest that BN may be characterized by a lower signal tracking surprising control-related outcomes. This reduced activation was detected in a brain area involved in in preparing to inhibit behavior and processing expectation violations. In individuals with current BN, such blunted state-dependent signaling could contribute to difficulty stopping eating and resisting urges to induce vomiting after eating. Fasted and fed-state data collection from a symptomatic sample, using a variety of cognitive control tasks, is underway. However, this initial characterization of the impact of eating on control-related decision-making in remitted BN may have direct implications for the learning required to inhibit and change behavior with treatment.
To eat or not to eat? Value-based decision-making in anorexia nervosa
Stefan Ehrlich MD PhD1,2 Arne Doose MSc.1 Joseph A. King PhD,1,
1Division of Psychological and Social Medicine and Developmental Neuroscience, Faculty of Medicine, Technische Universität Dresden,
2Eating Disorder Treatment and Research Center, Department of Child and Adolescent Psychiatry, Faculty of Medicine, Technische Universität Dresden,
Introduction: Individuals with anorexia nervosa (AN) engage in maladaptive behaviors (restrictive food choice, over-exercising) which may originate in altered decision-making. Delay discounting rate, a meta-control parameter gauging the relative preference of larger later over smaller sooner rewards, may help elucidate aberrant value-based decision-making in this enigmatic disorder.
Methods: We conducted a series of behavioral and fMRI studies using two different validated paradigms and computational modelling as well as the analysis of brain connectivity to quantify the rate of delay discounting and the associated neural correlates. Participants included acutely underweight female AN patients (acAN) at two timepoints (i.e. again after partial weight restoration), recovered former patients (recAN) and age-matched healthy controls (HC).
Results: At the behavioral level, patients at various stages of illness did not show any alterations in discounting rate, but choice reaction time was faster and more consistent in acAN. Furthermore, in contrast to the other groups, delay discounting was anti-correlated with hunger signals in acAN as measured via serum concentrations of the “hunger hormone” ghrelin. Suggestive of altered neural efficiency, acAN patients recruited the frontoparietal network significantly less than HC during decision making and showed increased coupling between dorsal anterior cingulate and posterior brain regions as a function of decision difficulty. However, these alterations were relatively normalized after partial weight-restoration and no differences were detectable between recAN and HC.
Conclusions: The results of these studies support the notion of an altered capacity to delay reward in the acutely underweight state of AN. Importantly, however, they indicate that aberrant value-based decision-making may not be a core trait of AN and might be remediable by treatment.
Relations between resting state functional connectivity and structural brain changes in anorexia nervosa
Friederike I. Tama,b ([email protected]), Fabio Bernardonia ([email protected]), Ilka Boehma ([email protected]), Maria Seidela ([email protected]), Daniel Geislera ([email protected]), Joseph A. Kinga ([email protected]), Stefan Ehrlicha,b ([email protected])
a Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany.
b Eating Disorder Treatment and Research Center, Department of Child and Adolescent Psychiatry, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany.
Introduction: Structural and functional magnetic resonance imaging (MRI) studies have shown considerable alterations in individuals with acute anorexia nervosa (AN), but the underlying mechanisms are not fully understood. In functional MRI research, resting state functional connectivity (rsFC) is a promising tool to characterize brain networks and their potential role in AN.
Methods: In a series of studies (using identical study designs and criteria), high-resolution 3D T1-weighted structural and resting functional MRI scans were acquired from young female patients with acute AN at the beginning of treatment and after short-term weight restoration, as well as from individuals long-term recovered from AN. To characterize rsFC, a number of different approaches were used.
Results: Our structural MRI studies indicated a global reduction in cortical thickness and gyrification in acute AN patients, which rapidly reversed after short-term weight restoration. Via independent component analysis, an abnormal rsFC was shown in the fronto-parietal network and the default mode network in acute AN, with only partial restoration after long-term recovery. Voxel-wise measures confirmed local alterations of resting state brain activity in several brain regions including the fronto-parietal network in acute AN. Graph-theoretical metrics provided evidence for an altered global brain network architecture in acute and long-term recovered AN.
Conclusions: Our research further elucidates alterations in rsFC in AN and their relations to structural brain changes, which are in line with recent findings of the ENIGMA-ED working group.
The role of malnutrition in the balance between small-world and randomic features of brain networks in Anorexia Nervosa: a multimodal study
Angela Favaro, Enrico Collantoni
Department of Neurosciencs, University of Padova
Background: Recent research in the field of neuroimaging indicates that brain correlates of AN could be better described as alterations in spatially distributed and interconnected neural systems rather than dysfunctions in single and spatially isolated areas. This evidence is consistent with the general observation that structural and functional brain alterations in psychiatric disorders can be better explained based on their covariance patterns rather than in terms of their localization. A powerful tool to describe the organization of brain networks based on their covariance patterns has recently been offered by connectomics, which allows evaluation of the brain as a complex network, and its alterations as modifications in the properties that govern its global or regional architecture. One of the main advantages of using connectomics tools to evaluate brain structure and function is that they allow evaluation of brain regions not as discrete and isolated elements, but as components that interact with each other based on their topological characteristics.
Methods: In this presentation, we will review the recent applications of connectomics tools in the study of AN and focus in particular on the findings of our research group that investigated the covariance patterns of brain areas both from a morphological/structural and from a functional point of view. Brain graphs will be built in a sample of 36 patients with AN and 36 healthy controls using cortical thickness, gyrification, probabilistic tractography, and fMRI data: similarities and differences between different neural measures will be analysed and discussed.
Results: We found an unbalanced connectome wiring in AN patients in comparison to healthy controls, in graphs built on cortical thickness, DTI-based tractography and fMRI, but not in graphs based on gyrification index. Patients with AN showed a reduced network clustering and a re-organization of network hubs. Many parameters seem to be influenced by malnutrition and loss of cortical volume.
Conclusion: Patients with AN show alterations in the topological characteristics of brain networks at a global as well as at a regional level. Patients with AN showed differences in hubs distribution, providing evidence of the presence of a different functional architectural backbone. These changes involve areas that are crucial in the neurobiology and pathophysiology of AN.
Cortical structure in anorexia nervosa: a complex picture from a multi-parameters analysis
Enrico Collantoni, Angela Favaro
Department Neurosciences, University of Padova
Background: Studies that evaluated brain morphology in the acute phases of anorexia nervosa (AN) demonstrated alterations in various parameters that describe distinct cortical aspects and that are differently related to both developmental, atrophic, and pseudo-atrophic changes. Recently, alongside more conventional cortical indices such as volume, surface, thickness, and gyrification, novel and non-redundant parameters have been used, in the attempt to better characterize the cortical structure in AN. Among these, absolute mean curvature, fractal dimension, and sulcal depth have proven to be useful in capturing peculiar cortical aspects and contributed to highlighting that the acute phases of AN are probably characterized by a reduction in cortical complexity and by a cortical flattening.
Methods: In this presentation, we will describe the results obtained using different morphological indices in the characterization of the cortical structure, namely cortical thickness, gyrification index, gyrification gradient, fractal dimension, and sulcal morphology (sulcal depth and width). Two samples were included in the present study. The first was composed of 38 patients with acute AN, 20 who fully recovered from AN, and 38 healthy women (HW); the second included 58 adolescent patients with AN and 53 healthy controls with a longitudinal follow-up.
Results: Fractal dimension seems to be a sensitive index to measure cortical alterations in AN, showing correlations with both body mass index and duration of illness. When compared to HW, patients with acute AN displayed lower fractal dimensionality, higher width and depth values in specific cortical sulci. A negative correlation exists between sulcal width and gyrification gradient. Specific associations between BMI and illness duration and factors encompassing sulcal width and depth values were evidenced.
Discussion: Our results suggest the presence of alterations in fractal dimension and sulcal morphology which seems to have a clear relationship with malnutrition and its duration.