Neurobiology of Abnormal Emotion and Motivated Behaviors

Integrating Animal and Human Research

Susan Sangha, Dan Foti

• Publisher: Academic Press
• Year: 2018
• ISBN:
  9780128136942
• Topic: Biological Sciences
• Subtopic: Neuroscience
• Index: Biological Sciences

Neurobiology of Abnormal Emotion and Motivated Behaviors: Integrating Animal and Human Research pulls together world-renowned leaders from both animal and human research, providing a conceptual framework on how neuroscience can inform our understanding of emotion and motivation, while also outlining methodological commonalities between animal and human neuroscience research, with an emphasis on experimental design, physiological recording techniques and outcome measures. Typically, researchers investigating the neurobiology of emotions focus on either animal models or humans. This book brings the two disciplines together to share information and collaborate on future experimental techniques, physiological measures and clinical outcomes.

• Integrates animal and human research to aid readers in discovering a clear path forward for translating basic science to clinical applications
• Provides overviews of the most recent research into the neuroscience behind maladaptive behaviors and psychiatric disorders
• Explores the commonalities in methods and outcome measures between animal and human researchers and how those commonalities can be harnessed for future collaboration and translational work

Section II

Impulsivity and Stress in Eating Disorders

Outline

• 3 Impulsivity, Stress Reactivity, and Eating Disorders
• 4 The Genetic Diathesis of Eating Disorders: Critical Roles for Puberty and Ovarian Hormones
• 5 Animal Models of Behavioral and Neuroendocrine Components of Eating Disorders
• 6 A Framework for Elucidating Causes and Consequences of Malnutrition in Anorexia Nervosa

3

Impulsivity, Stress Reactivity, and Eating Disorders

Sarah Fischer¹, Joseph Wonderlich¹ and Kendra D. Becker², ¹George Mason University, Fairfax, VA, United States, ²Harvard Medical School, Boston, MA, United States

Abstract

Negative urgency (NU) is the tendency to act rashly while distressed. Binge eating, the consumption of a large amount of food with associated loss of control, is often triggered by increases in negative affect. NU has strong associations with binge eating in nonclinical samples, predicts the onset of binge eating in youth, predicts increases in binge eating over time, and interacts with shifts in negative affect to predict binge eating in daily life in women with eating disorders. Outcome expectancy endorsement differentiates specific impulsive behavioral choices among those with high NU. These expectancies may represent a prepotent response that is made more salient by shifts in negative affect. Recent research indicates that activation in response to appetitive or emotional cues in the prefrontal cortex is associated with urgency. These studies suggest that the neurobiological underpinnings of this trait may be linked to taxed inhibitory control.

Keywords

Impulsivity; stress reactivity; eating disorder; negative urgency; cognition

In this Chapter

• Introduction 43
• Current Models 44
  • Impulsivity and Binge Eating 44
  • Negative Urgency and Binge Eating 45
• Mechanisms 47
  • Negative Urgency and Expectancies: Expectancies as a Cognitive Representation of Prepotent Response 47
  • Neurobiological Underpinnings of Negative Urgency 49
• Future Directions 52
• Highlights 53
• References 53
• Further Reading 58

Introduction

Eating disorders (EDs) affect 5%–7% of the population. Anorexia nervosa (AN) is characterized by restriction of eating and developmentally abnormal weight loss, as well as distorted cognitions concerning the importance of weight and shape in self-evaluation (APA, 2013). Bulimia nervosa (BN) is characterized by episodes of binge eating and inappropriate compensatory behavior, as well as over-valuation of weight and shape. Binge eating disorder (BED) is characterized by repeated episodes of binge eating without associated compensatory behavior. Finally, otherwise specified feeding and eating disorders (OSFED) may include any combination of the symptoms described earlier. On average, EDs onset aged between 12 and 22 years (Hudson, Hiripi, Pope, & Kessler, 2007; Kessler et al., 2013; Swanson, Crow, Le Grange, Swendsen, & Merikangas, 2011). Women are more likely to be diagnosed with EDs than men, although the base rates of BED are more similar in men and women. Additionally, the base rates of BN, BED, and OSFED are similar across ethnic groups in the United States (Marques et al., 2011).

Binge eating refers to consuming an objectively large amount of food in a relatively short period of time with an associated loss of control over eating (APA, 2013). The term subjective binge refers to the sense of loss of control over eating an amount of food that most people would consider “normal.” Both types of binge episodes may be present in all ED diagnoses. Additionally, there are no differences in other symptom severity or additional psychopathology between people who primarily engage in objective binges and those who engage in subjective binges (Mond, Latner, Hay, Owen, & Rodgers, 2010). Thus binge eating is central to the pathology of EDs and cuts across diagnostic boundaries and weight categories.

The goal of this chapter is to describe a body of work that examines the role of negative urgency (NU), the tendency to act rashly while experiencing distress, in the perpetuation of binge eating. First, we will provide context for this research by briefly reviewing the emotion regulation model of binge eating. Next, we will review a series of studies that examine the relationship of NU to binge eating in in cross-sectional, clinical, prospective, experimental, and ecological momentary assessment (EMA) studies. Finally, we will briefly review the potential neurobiological underpinnings of NU and questions for future research in this area.

Current Models

The emotion regulation model of binge eating conceptualizes this behavior as a maladaptive, although temporarily effective, mechanism to reduce negative affect (Haedt-Matt & Keel, 2011). Binge eating is hypothesized to distract one from an aversive stimulus (e.g., negative affect) with the use of a concrete stimulus (food) (Heatherton & Baumeister, 1991; Pearson, Wonderlich, & Smith, 2015). Thus it is negatively reinforced. Negative affect may be triggered by self-comparison or aversive self-related cognitions (Pearson, Zapolski, & Smith, 2015). Women with EDs are considered at heightened risk for binge eating under these conditions. First, self-control and cognitive resources may be depleted because of the food restriction that is typical in EDs (Pearson et al., 2015). Second, food cues or positive beliefs about food reward may become more acutely salient under conditions of acute stress or negative affect (Pearson et al., 2015). Several laboratory and EMA studies support the hypothesis that negative affect precedes binge eating episodes in women with EDs (Cardi, Leppanen, & Treasure, 2015; Engel et al., 2013; Smyth et al., 2007), although data are mixed regarding whether or not negative affect decreases following binge eating (e.g., Haedt-Matt & Keel, 2011; but see Berg et al., 2013; Engel et al., 2016). Data collected via EMA are particularly compelling, as this form of data collection occurs in the participant’s natural environment in “real time.” This allows researchers to establish that negative affect increases prior to binge episodes and is not biased by retrospective recall (e.g., Smyth et al., 2007).

Impulsivity and Binge Eating

Researchers have hypothesized that personality traits play a role in the etiology and maintenance of EDs (Farstad, McGeown, & von Ranson, 2016). Metaanalyses indicate that traits such as perfectionism and negative affectivity are elevated among all EDs (Farstad et al., 2016). However, results are less clear when examining the literature on impulsivity. Historically, there has been great interest in the role that trait impulsivity plays in EDs. Individuals with AN often present as highly controlled and avoidant, while some individuals with BN present for treatment with comorbid behaviors such as substance abuse and borderline personality disorder (O’Brian & Vincent, 2003). Additionally, a central component of binge eating behavior is loss of control. The behavior itself is considered impulsive. Thus individuals with BN are often characterized as elevated on trait impulsivity (Fahy & Eisler, 1993). A closer examination of the literature, however, reveals that it is not that simple. Although individuals with BN are often elevated on measures of impulsivity compared to individuals with AN, they have similar levels of impulsivity compared to individuals without eating pathology (Bushnell, Wells, & Oakley-Brown, 1996; Fahy & Eisler, 1993).

The UPPS-P model of impulsivity provides a framework that explains these inconsistent findings. The original model was derived from exploratory and confirmatory factor analyses of most major self-report trait–based measures of impulsivity (Whiteside & Lynam, 2001). All major structural trait models of personality have an “impulsivity” component. However, not all self-report measures that are labeled “impulsivity” actually assess the same construct. One questionnaire may have several questions that best represent sensation seeking, while another may have a mix of questions representing lack of deliberation and lack of perseverance. Thus, historically, the ED literature did not have a consistent method of measuring impulsivity. The use of the UPPS-P model has led to a much clearer delineation of the role of trait impulsivity in EDs.

The model has five impulsivity related constructs. Lack of deliberation reflects failure to plan ahead. Sensation seeking reflects a drive for thrilling sensations. Lack of perseverance reflects an inability to focus on goals while experiencing boredom. Positive urgency reflects the tendency to act impulsively while in a positive mood state (Cyders et al., 2007). NU reflects the tendency to act rashly while in a negative mood state. Parallel to self-report assessments of impulsivity, laboratory tasks purporting to assess impulsivity actually measure a variety of constructs. Prepotent response inhibition, typically represented in go/no-go tasks, refers to the ability to suppress dominant responses. In a metaanalysis, self-reported NU is associated with difficulty in prepotent response inhibition with a weighted mean, r, of 0.11 (Cyders & Coskunpinar, 2011). As NU reflects acting rashly in response to negative affect, we hypothesize that individuals with high levels of NU have difficulty inhibiting their habitual or dominant urges during periods of acute stress or negative affects.

Negative Urgency and Binge Eating

NU has been consistently linked to binge eating and is elevated in individuals with EDs (Culbert, Racine, & Klump, 2015; Pearson et al., 2015). Cross-sectional studies have established that when all UPPS-P traits are simultaneously examined in the same model, NU has a moderate-to-strong positive association with binge eating and other ED symptoms, while other traits have associations ranging from null to low (Fischer & Smith, 2008; Fischer, Smith, & Cyders, ...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• Introduction Emotion and Motivated Behaviors: Integrating Animal and Human Neurobiology Research
• Section I: Emotion-Related Impulsivity Across Disorders and Species
• Section II: Impulsivity and Stress in Eating Disorders
• Section III: Interaction of Stress and Drug-Seeking
• Section IV: Learning to Inhibit the Fear Response
• Section V: Abnormal Emotional Reactivity Versus Regulation Across Disorders
• Perspectives and Future Directions for Integrating Animal and Human Neurobiology Research on Abnormal Emotion and Motivated Behaviors
• Index