Motivation and emotion/Book/2019/Food and fear

Food and fear:
What impact does the food we eat have on our experience of the emotion of fear?

Overview

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Figure 1. An ominous open fridge; fear of the food that may be inside.

With regards to eating behavior, human beings are very much affected by their emotions: quantity, frequency of meals, and the food we choose are all dependent on many variables, not all of which are related to physiological needs (Gray, 1987). One of the primary emotions, fear, plays a significant role in recorded eating behaviors. Fear is a psychological state or biological feeling that someone experiences when there is a perceived danger or threat to their well-being (Kalat & Shiota, 2007). Fear’s process within the brain follows an important path in the development of anxiety disorders, phobias and eating disorders which closely link with the relationship of food. There is an increased prevalence of eating disorders in Western societies, which raises questions as to the role that emotions play in the etiology of these societal issues (Canetti, Bachar & Berry, 2002). The amygdala’s interpretation of stimuli and the activation of ‘flight-or-fight’ from the automatic nervous system provides valuable insight into the process of fear within food.

Case study 1.1
 

Macht (1999) developed a questionnaire to systematically examine the effects of four basic emotions, anger, sadness and joy on a number of eating characteristics. Two-hundred and ten subjects (107 females and 103 males) between 19 and 44 years of age volunteered to participate. The Three Factors Eating Questionnaire was used to measure restraint and deprivation of an individual and was calculated by using items from the Cognitive Restraint Scale.

Participants reported in this questionnaire an increased appetite when experiencing anger and joy. However, a significantly lowered appetite was identified when individuals experienced the emotions of fear and sadness. This finding was also mirrored in Mehrabian’s (cited in Canetti, Bachar & Berry, 2002) investigation of the relationship between different emotions and the amount of food intake; similar results were yielded by this investigation. Macht (1999) also found that eating scores of negative emotions correlated low and positive with body mass index, low and negative with dietary restraint.

The results of this case study highlight the correlation between emotional status and appetite. The finding of decreased feeling of hunger and hunger symptoms when exposed to situations of fear triggering emotions requires further analysis of why this occurs. By focusing of fear and food, we can address the following: what impact does the food we eat have on our experience of the emotion of fear?

Focus questions:

  1. What is fear?
  2. How does fear impact what we eat?
  3. What psychological theories are involved?
  4. What are the consequences of unresolved fears?
  5. How can this be treated?

What is fear?

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Figure 2. The Scream, created by Edvard Munch. A depliction of fear within artistic representation.

Emotions have a key influence on our basic behavioral systems, serving a motivational function within both humans and animals (Macht, 2008). Fear is a psychological state or biological feeling that someone experiences when there is a perceived danger or threat to their well-being (Kalat & Shiota, 2007). This basic human emotion is defined through its clear cognitive attributes, intense feelings and direct actions. Fear is drawn out by biological dangers (e.g. spiders or moths) or socio-cultural dangers (e.g. strangers or angry facial expressions) (Reeves, 2015). Fear is highly adaptive and is really important in its use as a survival mechanism. Through its coping functions of protecting or avoiding, fear enables the ability to deal with fundamental life tasks. Once the stimulus is no longer a threat to the individual, the physiological reaction gradually subsides (Dias, Banerjee, Goodman, & Ressler, 2013).

Most of our fears are learned through either evolutionary development (e.g. fear of snakes) or are developed through our personal experience, i.e. we have no predisposition to these fears (e.g. fear of guns) (Kalat & Shiota, 2007). The fear of food is an example of a learned fear through individual experience, such as fear of perishable foods, undercooked foods or unhealthy foods. Fear and anxiety share similar experiences as they are both distinguished by feelings of danger or dread and a sense of being threatened (Kalat & Shiota, 2007). However, it is the individual interpretation and subsequent action towards the fear which causes its effect to be a positive or negative experience (McNally & Westbrook, 2006). It is important that we adapt positive defensive behaviors towards a perceived fear, otherwise it will consequently impact on psychological well-being.

The emotional function of fear when interacting with food has historically served a valuable purpose (Levenstein, 2013). All animals developed a necessary fear of particular types of food which were known to be poisonous or deadly, such as the development of taste that rejected bitter foods. But as this predisposed function of taste is no longer a necessity, we can now analyse individual psychological reactions to food.

Review Questions

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What other emotion is closely linked to fear?

Anger
Sadness
Anxiety
Joy


Fear of food from a psychological perspective

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Every human emotion is considered a driver to particular behaviours (Kalat & Shiota, 2007). Emotional drivers can be measured through particular physiological responses such as rise in heart rate or brain activity (Kalat & Shiota, 2007). These provide insight into the emotional arousal of an individual experiencing a particular emotion such as fear. Previous scientific research of startle behavior in humans and other animals has allowed for further insight into emotion-related neurology in laboratory settings. As a result of this research, we have discovered valuable information about the biology of fear and anxiety which can help address a variety of complex questions (Kalat & Shiota, 2007).

The amygdala and fear conditioning

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Figure 3. The amygdala which is located within the brain's temporal lobe, where it processes information that would enable it to determine if it was "dangerous" or "safe".

The characteristics of a normal response to fear, including the fear-potentiated startle is mediated by the brain’s fear network main feature, the amygdala (Carlsson, Petersson, Lundqvist, Karlsson, Ingvar, & Öhman, 2004). In order for us to modify our behaviour when interacting with a perceived threat or danger to one’s safety, the amygdala has to receive and process the information within a given scenario (Kalat & Shiota, 2007). The amygdala is located in the brain’s temporal lobe and is a bilateral structure. It receives external input which represents vision, hearing, pain and other senses. With this collected information, the amygdala is well informed and is able to associate various stimuli with dangerous outcomes to follow them.

All emotions according to Gray (1987) represent a reaction to a ‘reinforced event’ or to signal to us the impending reinforcement of an event. These ‘reinforced events’ amount to rewards or punishments, including the removal of a reward or the failure of an expected reward to occur. Pavlovian fear conditioning seen through the “Little Albert” experiment which allowed an understanding into the form of learning that happens when there are consequences to a ‘reinforced event’ (Maren & Fanselow, 1996).

For more information:

The automatic nervous system and the "fight or flight" response

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A strong emotional arousal from fear or anger activates the sympathetic nervous system (SNS). This readies the body and organs for a brief, quick burst of fight-or-flight activity (Kalat & Shiota, 2007). The body responds by increasing its heart rate, rapid and irregular breathing (to get oxygen to the muscles), increased sweating, change in speech and many other functions. All of these functions serve the purpose of being able to respond effectively to the present or incoming stimuli. The SNS is a part of the automatic nervous system (ANS) and operates together through a series of interconnected neurons (McCorry, 2007). Researchers have identified a pattern of the automatic nervous system where activation has occurred in situations where are ‘threat’ occurs rather than situations that present as ‘challenges’. The flight-or-flight response would only activate in a situation where the individual believed they had no control over the threat (Kalat & Shiota, 2007). The processing of threatening stimuli allows the body to respond by readying the individual or animal to flee from the adverse events or readying to aggressively defend and fight in other events (Reeves, 2015).

As fear’s copy function is to protect or avoid, this can be linked to the theory of flight-or-flight (Reeves, 2015). Fear when exposed to stressors can result in temporally-patterned adaptive biological processes that mobilize energy to respond (Moon, Eisenberger & Taylor, 2009). But this finding within Moon et al’s (2009) research determined that fear’s typical response to threatening situations is to withdraw. However, when the threatening stimulus is food, it has found to cause different reactions dependent on the psychological disorder that is experienced. When comparing specific phobias to eating disorders, fight-or-flight reaction is dependent on the individual.


For more information:

  Fight or Flight Response (6 min., video)

Review Questions

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What part of the brain is largely associated with the experience of fear?

The prefrontal cortex
The amygdala
The medulla
The temporal lobe


Psychological disorders and fear

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Figure 4. How someone who suffers from anorexia nervous views themselves.

The study of emotions can enlighten many areas with psychological disorders and research into psychological disorders conversely does the same for emotions (Kalat & Shiota, 2007). Fear is an example of a highly researched area which has yielded a variety of results significant to many psychology fields, including biological, cognitive and social. Fear can occur in a variety of cases, whether there are threats internal or external to an individual. With this, we can consider fear to be a strong element in psychological disorders. The fear of food can be observed in anxiety disorders and phobias, such as germaphobia or pseudodusphagia (fear of choking) and even with conditioned responses to allergies (Levenstein, 2013). It can also be found in clinically diagnosed anorexia nervosa and other eating disorders. The most extreme level of fear found within these cases have severe and profound effects of an individual’s ability to thrive. With all these cases in mind, we can consider the fear of food to be a common fear, as fear manifests itself in a variety of ways.

Anxiety disorders and phobias

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Individuals who experience specific phobias react to stimuli with excessive fear and avoid the specific stimuli (Ipser,  Singh, & Stein, 2013). A specific phobia is defined as a heterogeneous collection of fears and avoidance of a broad range of specific objects or situations (Rapee & Barlow, 2002). Having a phobia such as small animals, heights, blood or spiders is actually quite common in individuals, as it is our personal alarm system that protects us. Individuals who have a specific phobia represent 11% of the general population (Antony, 2002). However, it can become a serious issue. If the fear of a stimuli causes extreme anxiety, loss of control, panic attacks or paralysis, it becomes an anxiety disorder. To receive a diagnosis of a specific phobia, an individual’s fear must avoid the fear stimulus or endure exposure with extreme distress. The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) defined five types of specific phobia (see Table 1), and all sub types of phobias are categorized into each section (Antony, 2002; Ipse, et al. 2013).

Table 1.

The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) definitions of the five types of specific phobias:

Phobia Type Example
Animal Spiders, snakes, dogs, cats, mice, birds
Natural Environment Being near water, high places, storms
Blood-Injection-Injury Seeing blood, receiving injections, blood tests, watching medical procedures
Situational Driving, flying, elevators, enclosed places, bridges
Other (Other Situations) Vomiting, choking, loud sounds


Case study 1.2
 

Ipser, et al. (2013) conducted a meta-analysis of functional brain imaging in specific phobia systems. They wanted to determine if there was further evidence regarding its underlying functional neuroanatomy. Their analysis was an attempt to address inconsistencies across studies that included differences in signal strength and the type of specific phobia diagnosed in individuals. The meta-analysis that was conducted in extension to previous quantitative reviews of functional neuroimaging in specific phobias. It was hypothesized that on the basis of existing literature, greater activation would be observed in the phobic group relative to the controls in the amygdala and insula. The main findings within this study determined that the largest cluster of activation in patients with specific phobia in response to the stimuli were observed bilaterally in the anterior insula and amygdala. It can be observed within their results that the amygdala and insula are the primary responders to primary responders to phobic stimuli in specific phobia. This is consistent with findings amongst basic research on the fear response and with clinical imaging data observed within this study.

Anorexia nervosa

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Anorexia nervosa is found to be an extreme form of fear of food, due to the way the brain processes the consumption of food. Anorexia nervosa is an eating disorder with a chronic course and high mobility and mortality. Eating disorders are relatively rare within the general population and sufferers tend to deny or conceal their illness and avoid professional help (Smink, Van Hoeken, & Hoek, 2012). This eating disorder affects less than 1% of women and one tenth as many men, which has increased in its high-risk group of 15-19 year old girls.  Anorexia nervosa is characterised by severe restriction of food intake resulting in drastic weight changes, and extremely low body weight (Steinglass, Albano, Simpson, Carpenter, Schebendach, & Attia, 2012). Other characteristics include intense fear of weight gain and continuous self-evaluation of body shape and weight. The mortality rates of patients can be as high as 10%, and the likelihood of death is increased further with the duration of the illness. It has the highest death rate of all mental illnesses and is extremely difficult to treat. Steinglass et al (2012) highlight in their article the similarities between the clinical phenomena seen in Anorexia nervosa and anxiety disorders. This includes fears related to food and the abnormal avoidance techniques used in avoiding these fears. More specifically, symptoms of anorexia nervosa include behaviours organised around their irrational belief system.

When someone is eating, the stomach sends signals through the thalamus and to the insula where it determines hunger and hunger level (Frank,  Reynolds, Shott, Jappe, Yang, Tregellas, & O'reilly. (2012). The amygdala assesses the psychological response to the food, determining if it is good or bad. For individuals who have a brain without an eating disorder, the signal continues through the brain to the pleasure center (nucleus accumbens) and releases dopamine as they gain pleasure from the food consumed. The amygdala isn’t alerted to any issues, so the body continues eating. For someone who has an eating disorder such as anorexia nervosa, the anterior insula doesn’t give off any signals of hunger or increased hunger. An individual may consume the food, but there is no pleasure or dopamine response received. The amygdala assesses this situation with increased anxiousness, uncertainty and disturbance. This results in the decision that the food should not be consumed. The brain overall decides not to continue consumption of food or particular foods as it does not gain pleasure from it, resulting in extreme disturbances and an acute delusional impact (Hill, 2012).

Review Questions

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What common phobias are examples of the situational phobia type?

Being near water, high places, storms
Driving, flying, elevators, enclosed places, bridges
Seeing blood, receiving injections, blood tests, watching medical procedures
Vomiting, choking, loud sounds


Fear of food in research

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By analyzing fear and how it manifests in relation to food we can begin to understand how the food we eat can impact on our psychological and consumption experience of food. The theories and psychological disorders previously discussed can be applied to a variety of cases throughout psychology. By applying this to research and specific case studies we can fully understand the relationships between fear and food. Each case study represents the versatility of the human experience when it comes to mental health issues, and each present the theory and occurrence differently.


Case study 2.1
 

Nock (2002) treated a 4-year-old Latino boy who was referred by his parents for refusal to consume virtually all solid foods or fluids. The child never verbalized a fear of choking but his parents reported that he had not eaten solids foods since choking on partially solid baby food when he was 7-months-old. He still acquired adequate nutrition through soft baby food, oatmeal, water and protein drinks that the parents purchased for him. Although the child was normal size and weight for his age, he had developed some disruptive behavioral patterns including frequent arguments with family members and difficulties with peers at school. The study of the treatment process of the child determined that a behavioral treatment program using therapist and parent modeling, graduated exposure, and contingency management was effective in systematically increasing the range and volume of food and fluids consumed with a decrease in food-related anxieties.

This case study shows the extreme ongoing effect fear has after a traumatic incident. The amygdala can be considered to play a role in this particular instance of fear. After an incident occurred, the amygdala then assessed the experience and determined that solid foods were now a stimulus to avoid. Interaction with this new fear would increase anxiety and cause a avoidance reaction to prevent the same scenario from repeating. Chatoor, Conley and Dickson (1988) found that children who had experienced episodes of choking resulted in post-traumatic stress disorder. They further found that their fear of choking and subsequent food refusal appeared to represent a fear of dying. The fear in this case went above and beyond the baseline of fear of choking, but extreme fear of if the threat became permanent.

Case study 2.2
 

Gonzalez and Vitousek (2004) developed a clinical instrument called The Food Phobia Survey which was designed to identify foods that are avoided out of fear or guilt by individuals with eating disorders. This was then used in a principle study where 101 female participants were recruited from undergraduate courses at the University of Hawaii to fill out a questionnaire. Through the results of the questionnaire it was found that dieters associated significantly more fear/guilt with food items than non-dieting participants. They also found that these participants rated more food items in ways that met study criteria for designation as fear foods. Both groups perceive foods that were fattening to have an increased fear/guilt associated with them. For both groups, weight-related concerns accounted for significantly more variance in fear/guilt than other factors such as health concerns, appeal, convenience or mood.

The results of this study determine that fear plays a role for dieters' and non-dieters' decision making when it comes to food choice. Individuals associated higher levels of fear/guilt when it came to decision making in regards of weight-related concerns. Knight & Boland (1989) Found that weight-concerned individuals often limited their dietary selection and determined ‘safe’ and ‘unsafe’ foods, to ensure prevention of weight gain. The analysis of this case study can determine that there is a deep level of thought that goes into decision making to prevent the physical threat of weight gain for the individual. The participants in this case can be considered as fearful of unhealthy eating practices resulting in the consequence of weight gain.


Case study 2.3
 

Huse and Lucas (1984) conducted a study where they characterised dietary patterns of patients with anorexia nervosa. Medical records of 96 patients (93 females and 3 males) were obtained and the diet history of the two weeks before diagnoses was analysed. The mean age of the patients was 16.6 years old, with the age range between 11-24 years old. Through the analysis, it was found that there were several consistent types of dietary patterns which could can be directly linked with their severity of their disorder. It was found that the food that was restricted or removed from diet were typically associated with unhealthy foods, such as high fat content and high carbohydrates.

The typical results of dietary choice of anorexia nervosa sufferers determines the fear level is consistently associated across a variety of studies, as previously determined. But when looking at anorexia nervosa from an evolutionary perspective, Gatward (2007) determined that ‘fight-or-flight’ response can be observed within the depression and anxiety symptoms. The threat in this case is flight blocking feelings about the threat of food through food avoidance, and fight is the attempt of becoming more valuable and attractive through fasting and exercising. This notion of flight-or-flight within anorexia nervosa demonstrates the complexity of the relationship between the amygdala and the automatic nervous system.

Preventing and treating fear of food

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Fear and anxiety are central parts of clinical disorders and with an understanding of previous cases, its presence within future cases can be predicted (Kalat & Shiota, 2007). With this in mind, approaching the prevention and treatment of fears surfaced through stimuli such as food can be done so in an informed manner. The ability to alter emotional responses as circumstances change is a critical component of normal adaptive behavior and is often impaired in psychological disorders. In Hartley and Phelps’ (2010) review they discuss four emotional regulation techniques that have been investigated as a means to control fear: extinction, cognitive regulation, active coping, and reconsolidation (see Table 2). With an in depth knowledge of each technique, it can be applied in preventing ongoing fear within affected individuals.

Table 2.

Emotion regulation techniques suitable for anxiety disorders:

Emotional Regulation Technique Description
Extinction Extinction refers to the gradual decrease in the expression of the conditioned fear response that occurs when it is presented repeatedly without reinforcement of the unconditioned stimulus.
Cognitive Regulation Strategies Turning out cognitive strategies to generate more adaptive emotional and social reactions.
Active Coping Learning that the situation is linked to aversive consequences. Using this knowledge, it can reinforce an action that then diminishes the fear response.
Reconsolidation Disrupting the formation of the memory that has been consolidated before a behavior becomes concrete.

When approaching specific psychological disorders such as anorexia nervosa, a more specifically adapted method of treatment to ensure recovery is required.. Steinglass, et al. (2011) developed a brief exposure and response prevention intervention (AN-EXRP) for recently weight-restored individuals with anorexia nervosa receiving inpatient, behaviorally based treatment. The participants who were their pilot study to test the validity of this new measure were already receiving standard protocol treatment within the New York State Psychiatric Institute. This treatment consisted of structured, behaviorally based program in which unit privileges are contingent on eating all meals and achieving regular weight gain goals. The pilot study administered over 12 sessions intervention emphasizes confronting fear and anxiety around eating-related situations. The results of the intervention found that reducing premeal anxiety improved eating behavior, which was consistent across 3 measures of anxiety. This is an important finding in the investigation of alternative approaches to eating disorders, as food avoidance is a significant issue with sufferers. Reducing fear and anxiety is an important step in the recovery of all psychological disorders, including eating disorders and anxiety disorders.

Review Questions

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Which description matches the extinction emotional regulation technique?

Extinction refers to the gradual decrease in the expression of the conditioned fear response that occurs when it is presented repeatedly without reinforcement of the unconditioned stimulus.
Disrupting the formation of the memory that has been consolidated before a behavior becomes concrete.
Learning that the situation is linked to aversive consequences. Using this knowledge, it can reinforce an action that then diminishes the fear response.
Turning out cognitive strategies to generate more adaptive emotional and social reactions.


Further study

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Hartley and Phelps’ (2010) determine that although their emotional regulation techniques are valuable, there is much opportunity for further research into the most effective contexts in which these measures could be effectively used. This will enable a better translation of the research they developed for new treatment avenues for clinical disorders. There is a lack of research found overall that is related to the direct relationship between theory and food. This leaves potential opportunity for research to be conducted within this gap. Such research would not only be focused on phobias and eating disorders, but also the brain activation that occurs when eating specific food types. Food and fear can be approached from a variety of different psychological perspectives, leaving room for vast knowledge to be gained.

Conclusion

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The impact that the food we eat has on our experience of the emotion of fear has been seen through its effects on the brain. The psychological disorders surrounding fear and use avoidance reveal insight into how prevalent the fear of the food we eat may be within the broader psychological experience of humans and animals. By focusing on a key brain structure, the amygdala and the automatic nervous system, we can understand how a reinforced event creates fear and anxiety towards consumption practices. By reviewing and analyzing a variety of case studies we can observe that each experience of psychological distress is unique to one another. This concludes that what we eat and the experience of eating is dependent on an individual and their susceptibility to psychological disorders.

This chapter is an overview of the variety of experiences humans and animals can be involved in when engaging in eating practices. Our brain’s interpretation of the food impacts on whether the relationship between the food and us is to be positive or negative based on experienced situations or biological systems.

See also

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References

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Abramson, E. E., & Wunderlich, R. A. (1972). Anxiety, fear and eating: A test of the psychosomatic concept of obesity. Journal of Abnormal Psychology, 79, 317.

Antony, M. M. (2002). Specific phobia: A brief overview and guide to assessment. In Practitioner’s guide to empirically based measures of anxiety (pp. 127-132). Springer, Boston, MA.

Canetti, L., Bachar, E., & Berry, E. M. (2002). Food and emotion. Behavioural processes, 60(2), 157-164.

Carlsson, K., Petersson, K. M., Lundqvist, D., Karlsson, A., Ingvar, M., & Öhman, A. (2004). Fear and the amygdala: manipulation of awareness generates differential cerebral responses to phobic and fear-relevant (but nonfeared) stimuli. Emotion, 4(4), 340.

Chatoor, I., Conley, C., & Dickson, L. (1988). Food refusal after an incident of choking: A posttraumatic eating disorder. Journal of the American Academy of Child & Adolescent Psychiatry, 27(1), 105-110.

Dias, B. G., Banerjee, S. B., Goodman, J. V., & Ressler, K. J. (2013). Towards new approaches to disorders of fear and anxiety. Current opinion in neurobiology, 23(3), 346-352.

Gatward, N. (2007). Anorexia nervosa: An evolutionary puzzle. European Eating Disorders Review: The Professional Journal of the Eating Disorders Association, 15(1), 1-12.

Gray, J. A., (1987). "The psychology of fear and stress". New York, USA: Cambridge University Press.

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Frank, G. K., Reynolds, J. R., Shott, M. E., Jappe, L., Yang, T. T., Tregellas, J. R., & O'reilly, R. C. (2012). Anorexia nervosa and obesity are associated with opposite brain reward response. Neuropsychopharmacology, 37(9), 2031.

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Steinglass, J., Albano, A. M., Simpson, H. B., Carpenter, K., Schebendach, J., & Attia, E. (2012). Fear of food as a treatment target: exposure and response prevention for anorexia nervosa in an open series. International Journal of Eating Disorders, 45(4), 615-621. https://doi.org/10.1002/eat.20936

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