Neural circuits underlying emotion dysregulation in bulimia nervosa
Poster No:
625
Submission Type:
Abstract Submission
Authors:
Kaixi Zhang1, Zhen Yuan1,2, Zhiying Zhao1,3
Institutions:
1Centre for Cognitive and Brain Sciences, University of Macau, Taipa, Macau, 2Faculty of Health Sciences, University of Macau, Taipa, Macau, 3Yale School of Medicine, Department of Radiology & Biomedical Imaging, New Haven, CT, USA
First Author:
Co-Author(s):
Zhen Yuan
Centre for Cognitive and Brain Sciences, University of Macau|Faculty of Health Sciences, University of Macau
Taipa, Macau|Taipa, Macau
Centre for Cognitive and Brain Sciences, University of Macau|Faculty of Health Sciences, University of Macau
Taipa, Macau|Taipa, Macau
Zhiying Zhao
Centre for Cognitive and Brain Sciences, University of Macau|Yale School of Medicine, Department of Radiology & Biomedical Imaging
Taipa, Macau|New Haven, CT, USA
Centre for Cognitive and Brain Sciences, University of Macau|Yale School of Medicine, Department of Radiology & Biomedical Imaging
Taipa, Macau|New Haven, CT, USA
Introduction:
Up to 1% of young women around the world suffer from bulimia nervosa (BN) which is characterized by binge eating and inappropriate compensatory behavior (Mohajan & Mohajan, 2023). The etiology of BN is complex, and the neurobiological mechanisms underlying BN symptomology remain poorly understood.
Similar to anorexia nervosa (Seidel et al., 2018), another type of eating disorder, individuals with BN display difficulties in emotion regulation. There are some studies suggest that deficits in utilizing adaptive emotion regulation strategies, such as cognitive reappraisal in both phenotypes (Dikmeer, Ersöz Alan, & Foto Özdemir, 2023). Such deficits in emotion regulation are linked to BN symptomatology (Azzi et al., 2023). However, in contrast to AN, no neuroimaging studies have examined the neural mechanisms of emotion dysregulation in BN. In this cross-sectional fMRI study, we compared the brain activation levels in core emotion regulation pathways between individuals with subclinical BN (sBN) and healthy controls with no eating disorder symptoms.
Similar to anorexia nervosa (Seidel et al., 2018), another type of eating disorder, individuals with BN display difficulties in emotion regulation. There are some studies suggest that deficits in utilizing adaptive emotion regulation strategies, such as cognitive reappraisal in both phenotypes (Dikmeer, Ersöz Alan, & Foto Özdemir, 2023). Such deficits in emotion regulation are linked to BN symptomatology (Azzi et al., 2023). However, in contrast to AN, no neuroimaging studies have examined the neural mechanisms of emotion dysregulation in BN. In this cross-sectional fMRI study, we compared the brain activation levels in core emotion regulation pathways between individuals with subclinical BN (sBN) and healthy controls with no eating disorder symptoms.
Methods:
The current study recruited subclinical BN (sBN) female (n=22) and healthy control (HC) female participants (n=17) aged from 18 to 27 from the University of Macau, China. These young college students were screened and grouped based on the SCOFF questionnaire [] and interviews conducted based on DSM-5 criteria for BN. All participants were instructed to maintain a minimum fasting period of 12 hours prior to the experiment. They were allowed to drink water but were required to refrain from eating any food or consuming any other beverages. All experimental procedures were conducted in the morning.
The emotion regulation task used in this study was adapted from Phan et al., (Phan et al., 2005) which consisted of four conditions: View Neutral, View Negative, Regulate Reappraisal and Regulate Suppression. The latter two were representative emotion regulation strategies. All the picture stimuli used in the study were selected from the International Affective Picture System based on their valence and arousal.
Participants rated their level of negative emotion elicited by the images on a scale of 1-5 after viewing the pictures or emotion regulation. Generalized linear models were used to analyze and extract the activity levels from bilateral dorsolateral prefrontal cortex (dlPFC) and bilateral amygdala during the task using the beta-estimates extracted from these regions-of-interest (ROIs).
The emotion regulation task used in this study was adapted from Phan et al., (Phan et al., 2005) which consisted of four conditions: View Neutral, View Negative, Regulate Reappraisal and Regulate Suppression. The latter two were representative emotion regulation strategies. All the picture stimuli used in the study were selected from the International Affective Picture System based on their valence and arousal.
Participants rated their level of negative emotion elicited by the images on a scale of 1-5 after viewing the pictures or emotion regulation. Generalized linear models were used to analyze and extract the activity levels from bilateral dorsolateral prefrontal cortex (dlPFC) and bilateral amygdala during the task using the beta-estimates extracted from these regions-of-interest (ROIs).
Results:
In both groups, the negative emotion rating was lower in the View Neutral condition than the View Negative condition. However, there was no significant group differences in the emotion ratings when comparing the same conditions (p>0.05).
Independent-sample t-test revealed significant differences between the groups in the right amygdala (t = -2.567, p = 0.014) with the sBN showing lower responsiveness to negative stimuli in this region compared to HC participants.
Repeated-measures ANOVA revealed a significant emotion regulation strategy (regulateReappraisal, regulateSuppression) * Group (sBN, HC) interaction in bilateral amygdala (Left: F1,n = 4.630, p = 0.038, Right: df=1, F = 4.495, p = 0.041).
Post-hoc analysis revealed that HC group decreased the bilateral amygdala activation level during suppression of the emotion (Suppression condition) to a larger extent comparing to the sBN (Left: t =-2.836 p =0.007, Right: t = -2.329 p = 0.025), indicating failures in regulating negative emotion by the sBN group.
Independent-sample t-test revealed significant differences between the groups in the right amygdala (t = -2.567, p = 0.014) with the sBN showing lower responsiveness to negative stimuli in this region compared to HC participants.
Repeated-measures ANOVA revealed a significant emotion regulation strategy (regulateReappraisal, regulateSuppression) * Group (sBN, HC) interaction in bilateral amygdala (Left: F1,n = 4.630, p = 0.038, Right: df=1, F = 4.495, p = 0.041).
Post-hoc analysis revealed that HC group decreased the bilateral amygdala activation level during suppression of the emotion (Suppression condition) to a larger extent comparing to the sBN (Left: t =-2.836 p =0.007, Right: t = -2.329 p = 0.025), indicating failures in regulating negative emotion by the sBN group.
·In both groups, the negative emotion rating was lower in the View Neutral condition than the View Negative condition.
·Group activation in ROIs for various condition
Conclusions:
Our results suggest that individuals with BN symptoms (although not meeting the diagnostic criteria) are accompanied by reduced sensitivity to negative stimuli in the limbic pathway. Moreover, they were less efficient in down-regulating amygdala activity when using the maladaptive emotion regulation strategy compared to healthy. Giving the previously reported preference in using maladaptive strategies (Aldao et al., 2010), this finding shed light on the emotion deficits in the BN population.
Disorders of the Nervous System:
Psychiatric (eg. Depression, Anxiety, Schizophrenia) 1
Emotion, Motivation and Social Neuroscience:
Emotion and Motivation Other 2
Keywords:
Affective Disorders
Eating Disorders
FUNCTIONAL MRI
Limbic Systems
Psychiatric Disorders
1|2Indicates the priority used for review
Provide references using author date format
Azzi, R., (2023). The association between mental health and Bulimia Nervosa among a sample of Lebanese young adults: the indirect effect of difficulties in emotion regulation. BMC Psychiatry, 23(1), 335.
Dikmeer, N., (2023). The role of mindfulness on the psychological aspects of anorexia nervosa. Clinical Child Psychology and Psychiatry, 13591045231190675.
Mohajan, D., (2023). Bulimia Nervosa: A Psychiatric Problem of Disorder. Innovation in Science and Technology, 2(3), 26-32.
Phan, K. L., (2005). Neural substrates for voluntary suppression of negative affect: a functional magnetic resonance imaging study. Biological psychiatry, 57(3), 210-219.
Seidel, M., (2018). Processing and regulation of negative emotions in anorexia nervosa: An fMRI study. NeuroImage: Clinical, 18, 1-8.