More and more is being understood about eating disorders and the brain every day. As brain imaging improves and the study of genetics forges on, we are closer than ever to understanding the underlying neurology of eating disorders.
Read on to learn:
- How pleasure and fear impact the development of an eating disorder
- How different eating disorder behaviors show up in the brain
- Why it’s important to understand the neurology of eating disorders
Note: Eating disorders are complex, and many areas of the brain are impacted by an eating disorder. These are just a few neurological characteristics of eating disorders.
Neurobiology of Eating Disorders: What aspects of an eating disorder are correlated with neural responses?
ACTIVATED COGNITIVE CONTROL REGIONS OF THE BRAIN TO CONTROL NEGATIVE EMOTIONAL AND APPETITE RESPONSE
This 2021 study reviewed the physiological, emotional, and neural responses to body image and food stimuli people with anorexia and bulimia experience.
The study found that, when viewing food images, activation was seen in the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC) and medial orbitofrontal cortex (OFC) in people with anorexia. ACC and OFC activation indicates a negative emotional response to food.
ACC and DLPFC play a role in cognitive control of both emotions and appetite, which suggests that people with anorexia are attempting to control those responses so they don’t perform any actions, such as eating, as a reaction to negative emotions and appetite.
FEAR AND NEGATIVE EMOTIONAL IN RESPONSE TO BODY IMAGE STIMULI
In the same study, individuals with both anorexia and bulimia experienced an activation in ACC and the limbic system when shown stimuli related to body weight and shape. This indicates a negative emotional response to body weight and shape.
Individuals with anorexia had an increased amygdala reaction to bodyweight and shape images, especially large self-images. This represents an increased fear response to the idea of themselves in a larger body. That intense fear response is one explanation as to why people restrict food — to feel less fear and more in control of their surroundings.
Individuals with bulimia showed amygdala activation, but not to the same extent as individuals with anorexia did.
Body-image stimuli were found to be even more disturbing to people with eating disorders than food-related stimuli.
Related: Dialectical behavioral therapy is focused on identifying and managing negative emotions. Here’s how DBT can work for you in eating disorder recovery.
DECREASED ATTENTION AND INCREASED TOP-DOWN PROCESSING
Bottom-up processing is the process of forming perceptions based on external data and focuses on interpreting sensory information in real time. Top-down processing, on the other hand, relies on prior knowledge, experiences, and expectations.
Individuals with eating disorders showed an increased level of top-down processing and a decreased capacity for attention in response to body-shape stimuli. This means that people with eating disorders do not take in the raw data of how their body looks and feels in reality. Instead, they start with the idea of how their body is, and then “fill in the gaps” based on their imagined perceptions of self.
Essentially, people with eating disorders are unable to really pay enough attention to take in realistic sensory information related to their bodies, as it provokes too many negative emotions. So, they rely on the idea of how they look and feel. This perception is then mapped onto their reality.
Related: Body checking is a way people with eating disorders try to get more sensory information about their bodies, but this is why body checking is actually harmful (and how to stop doing it.)
HOW “LIKING” AND “WANTING” FOOD WORKS IN THE BRAIN OF SOMEONE WITH AN EATING DISORDER
In a psychological sense, “liking” refers to the impact of pleasant reward stimuli which, when consciously interpreted by your brain, can result in subjective pleasure. There are some “hotspots” in the brain that amplify feelings of pleasure in response to palatable (or likeable) tastes. “Wanting” is the incentive motivation to obtain and consume food rewards.
People without eating disorders have a normal connection between the neurological circuitry involving “liking” and “wanting,” and since they can also identify hunger and fullness cues in their body, they have a normal relationship to food. In other words, they eat what they want and stop when they are satisfied, both physically and mentally.
But people with eating disorders, especially individuals who struggle with binge eating, have a distinct disconnect between “liking” and “wanting.” Much like people with a substance use disorder, individuals who binge eat experience more “wanting” or cravings for food, without necessarily “liking” or deriving pleasure from eating.
There is also a disconnect between the brain and the body, which means that in the middle of a binge eating episode, a person might not realize they are full until they are extremely overfull. Even if they do notice fullness, their craving may not be satisfied, so they continue eating despite discomfort.
Related: This is how to identify and honor the four types of hunger in eating disorder recovery.
DOPAMINE RESPONSE IN INDIVIDUALS WITH EATING DISORDERS
Dopamine is a neurotransmitter, or brain chemical, that provides signals about the presence and intensity of reward. It also impacts learning, motivation, attention, and pain processing.
Studies show that individuals with anorexia have a hyperactive dopamine reward pathway, which makes them hypersensitive to things like food reward and emotional pain. In anticipation of satisfying food, people with anorexia will constrain themselves in order to avoid an unwanted or perceived as excessive reward response to food. In other words, they avoid food in order to avoid feeling the pleasure they expect they would feel if they ate. They avoid the feeling in fear of overeating, or out of a sense of guilt or greed over the pleasure of food.
Individuals with eating disorders involving binge eating have a reduced dopamine response. They expect to experience a certain amount of pleasure in response to food, but often do not experience as much pleasure as expected. The decreased pleasure response often leads individuals to binge eat, as they are trying to find the dopamine they expect to receive from food.
Finally, almost all individuals with an eating disorder (except individuals with Avoidant/Restrictive Food Intake Disorder) have a dopamine related reward response when it comes to weight loss. As an individual loses more weight, though, the dopamine response is lowered, which is why they feel the need to lose more weight. In this way, they are chasing that first initial “rush” of weight loss.
Many studies suggest that dopamine pathways are dysfunctional prior to the onset of an eating disorder, and are increasingly damaged as the disorder worsens.
Eating Disorders and the Brain: Why Understanding the Connection Between the Two are Important
Understanding eating disorders on a fundamental chemical level is important because:
- It demonstrates how eating disorders are both biological and psychosocial in nature
- Psychiatric treatment practices are informed by the chemical advances in the understanding of eating disorders
- It helps people with eating disorders feel more valid, as they understand that eating disorders are not a choice and they are not any one person’s fault
- Diagnosing someone with an eating disorder could be easier as brain scans become more affordable and commonplace
- Brain imaging could show whether someone’s neural pathways are altering to become more healthy
That last point is important: studies have shown that in recovery, your brain can form new neural pathways and connections. You will not always feel so afraid of food, or so driven to act on eating disorder behaviors. Your brain will respond better to stress and negative emotions, and will eventually not experience such cognitive distress in general.
So, keep up hope. You will not always feel like you do when you’re stuck in your eating disorder. It’s been clinically proven that the brain changes in recovery, after all.
If you or a loved one is suffering from an eating disorder, take the first step today and talk to someone about recovery or simply learn more about the holistic eating disorder recovery programs we offer.
