Anorexia: Wired Like Asperger's?

They do it because their brains are wired to. Girls with anorexia nervosa starve due to neural processing problems -- much like those associated with Asperger's disorder, a mild form of autism.

That's the latest theory of eating disorders, proffered in The Times (U.K.) by Janet Treasure, head of the Eating Disorders Unit at the South London and Maudsley Hospital NHS Trust.

In essence, faulty circuitry in the brain causes the restrictive, repetitive and obsessive behaviors of both disorders. Those with anorexia target the abnormal patterning toward food. Those with Asperger's focus intensely on other areas of interest.

Treasure's controversial thesis is based, in part, on commonalities that the two disorders share.

According to eating disorder experts, individuals with anorexia generally express trademark personality styles through food:

• Perfectionism. I want to look exactly like the fashion model ideal.
• Anxiety. I am terrified of being fat.
• Extreme rule-making. I will not eat more than 850 calories per day.
• Preoccupation with and rigid adherence to those rules -- to the point of social isolation. I plan all my meals two days in advance and count out my calories religiously so as to never go over my quota. I cannot eat out with others.

Experts say that individuals with Asperger's, too, have signature personality traits:

• Perfectionism (about areas of interest). I know my teacher is wrong about Route 41 crossing Highway 91 at Main Street, because I memorized the street map of my town.
• Hypersensitivity. The world outside my mind overwhelms me.
• Repetitive behaviors and rituals. I go to the library every day to read about cartography.
• Preoccupation and social isolation. My love of maps seem at odds with the rest of the world. I live in a parallel universe.

But while compelling, the observable similarities do not constitute scientific proof. " Just because it looks like a duck doesn't make anorexia an Asperger's duck, " says clinical psychologist Richard Pomerance, Ph.D, who has seen a number of Asperger's patients in his private practice near Boston. He points out that there are at least as many symptoms of Asperger's -- difficulty interpreting facial expressions and other social cues, for example--that do not show up in most anorexics.

Controversy aside, Treasure's theory certainly casts eating disorders in a new light. She says that anorexia is a disease grounded in human genetics and neurobiology. Genes orchestrate behaviors by coding for neurochemicals that signal each other in the brain, sometimes in abnormal ways.

This line of thinking is catching on within the eating disorders community. Researchers are using tools like DNA sequencers and PET scanners to "look under the hood" at the brainwork behind self-starvation behaviors.

Molecular biologists are hunting down the genes for anorexia that might seed the mind with a predisposition for anorexia.

The strongest candidates include genes involved with the serotonin system (which controls mood); dopamine centers (related to food repulsion, hyperactivity, and obsessive compulsive behaviors); and opioid receptors, (involved in reward and feeding control).

Other researchers are scanning the brains of individuals with anorexia for clues to the processing centers that might go awry. Again, serotonin pathways top the list.

Even evolutionary biologists are stepping up to the plate and offering their own hypotheses as to why anorexia lingers in the human species. At first blush, anorexics should be out of the game, given that infertility is a common effect of the disease. The answer may be that those who can exist on minimal calories during times of scarcity can keep the tribe alive and, in doing so, pass the culprit genes on to the next generation. It's survival of the species rather than the individual that matters.

But these biological underpinnings are only part of anorexia's complex mechanics, and Treasure is careful not to dismiss studies that point to culture and psychological issues as causes of and catalysts for eating disorders. Those studies do abound. For example, there is Anne Becker's work showing that the introduction of television into a population of Fijian teenage girls caused a surge of eating disorders in just three years.

Numerous studies show that sexual abuse, trauma, and even bullying can catalyze eating disorders.

So it seems that anorexia nervosa is rooted in both nature and nurture. From the nature and nurture perspective, a person may be born with "bad" genes, which produce faulty neurotransmitters and/or circuits. An individual with such a genetic make-up is a time bomb for distorted thinking about body image. Then, something in the person's environment eventually may light the fuse.

This makes sense when I hear stories like those of Laura, 65, whom I interviewed for Lying in Weight: the Hidden Epidemic of Eating Disorders in Adult Women. She was diagnosed with anorexia as a teen, recovered by 20, relapsed at 48, then recovered again. Laura is an identical twin. Her sister never had anorexia, and is, in fact, obese.

How do we explain the phenomenon of Laura and her sister, where two women share exactly the same genes but only one gets anorexia? Same genetic makeup, different life experiences.

As psychologist Cynthia Bulik, Ph.D. at the University of North Carolina, Chapel Hill, sums it up, "Genes load the gun. Environment pulls the trigger."

Comments

[joseph449008]

"At first blush, anorexics should be out of the game, given that infertility is a common effect of the disease."

The same sort of thing can be said of homosexuality. It has also been said of autism and schizophrenia. There's nothing new about this type of question. It's not surprising that there's variation in adaptiveness across the species (whether inherited or due to de novo mutations).

[KellyJadon]

Readers, you should know that Trisha Gura, Ph.D. is a highly intelligent science writer and medical journalist. I read her book, Lying In Weight, reviewed it, and interviewed her for my site.
Trisha Gura's personal story itself is fascinating. Lying In Weight gets an all-star rating!
Kelly Jad'on
www.BasilAndSpice.com
Syndicated Author and Book Views For a Healthy Live

[TherapyDoc]

Absolutely fascinating stuff, and I'm sure now we'll see a plethora of new dissertations linking disorders to genetics based upon the very template the APA suggests.

The future portends patients demanding money squandered under the microscope and traditional individual and family therapies will be eschewed as children/women gets even MORE out of their systems.

Munchausen-esque, I feel. The likelihood we'll lose a few in the process is my running hypothesis.

[girlwithglasses]

I'm pleased anytime that anorexia is shown to be something other than a symptom of vanity and the desire for attention.

I hope the research continues, but I'd hedge my bets that we'll not find one cause for anorexia just like there isn't one cause for depression.

[kellygrrrl]

Everything is rooted in BOTH nurture and nature.
parents and professionals really need to let go of this black or white idea and stay informed and watchful for both causes, triggers and symptoms.
Psychological disorders are complicated enough.
Let's remove the stigma
allow parents and pros to state clearly "This IS happening. This IS real."
While the "WHY" is extremely important from a research standpoint, I truly feel that the majority focus should be on treatment and family aid.
If your child is homosexual, a family needs to learn how to come to terms with the reality.
If your child has autism, a family needs to learn the ropes of resources available in their area - same as with an eating disorder.
As much as you want to believe there is a CURE for anorexia, the truth is that it will forever be a part of a person's psychological makeup. It is more akin to alcoholism than anything else. Only you can't go with the "All or Nothing" mentality. You have to find a healthy relationship with food, and you have to work on it every day for the rest of your life. That is the reality!!!

[hankm]

Here we go again with the "gene" thing.

In one sentence, we hear that behavior based on genetics is a theory and that researchers are actively hunting for those genes responsible.

But in the end, we are told by a psychologist that "genes load the gun." Based on what proof? Their diploma?

It is very unpopular these days to say that people are not the victim of their genes, but that they are 100% responsible for their condition in life.

Fortunately, difficult though the journey may be, taking full responsibility for one's situation and personal growth is the only way out.

After years and years of attempts to prove otherwise, behavioral gene theory is only a cop-out.

It's a difficult pill to swallow, but it's the only pill you need.

[seasalt]

It seems to me that you are frightened by the very idea that we are influenced by our biology.

Would you say that a person with hypothyroidism is "copping out" when they take thyroid hormones? Is a diabetic "copping out" when they inject insulin?

Why is it so hard to swallow that multiple-h­ormone-sys­tem and/or neurotransmitter failures could be a PART of the anorexia picture?

How is researching human biology a "cop out"?!?

[joseph449008]

"It is very unpopular these days to say that people are not the victim of their genes, but that they are 100% responsible for their condition in life."

Would you say someone with Down's syndrome is 100% responsible for their condition in life?

(Not to mention that the social enviornment also has some responsibility).

We're all different from one another. And one of the main reasons we are different is our genes.

[ThatsNotFunny]

"How do we explain the phenomenon of Laura and her sister, or that of Mary Kate and Ashley Olsen, where two women share exactly the same genes but only one gets anorexia"

A quick look at Wikipedia would have told you that Mary-Kate and Ashley Olsen are NOT identical twins. They are Fraternal twins. They do not have identical genes, as you suggest.

[LauraCollins]

It is wonderful to see these issues being discussed. A few years ago it was heresy to suggest that eating disorders were biologically based.

These days it is only "controversial."

Most illnesses are both "nature" and "nurture," including heart disease and cancer and phenylketonuria. The problem is that most treatment out there for eating disorders focuses on the parts of the environment that used to be believed to be causative.

"Environment" includes prenatal nutrition, dieting, inappropriate athletics, viruses, and low-fat eating. The studies that show a correlation with abuse and neglect and body image issues do not indicate causation.

As a result, most treatments available for eating disorders don't work. The only treatments that are known to be more effective than doing nothing are Cognitive Behavioral Therapy and the Family-Based Maudsley Approach. Neither of those approaches involve the past, nor do they treat the environment as causative.

I look forward to the day that it is "controversial" to treat people based on antiquated ideas of causation, like family dysfunction and a desire to be thin.

[seasalt]

"Genes load the gun. Environment pulls the trigger."

Exactly. Succinctly and perfectly well-said. "Nature VERSUS nurture" is a false dichotomy. It's "nature AND nurture".

In the case of the twins where one is obese and one is anorexic, the same genetically-based brain dysfunctions could result in anorexia AND obesity. One expresses her food obsession/severe anxiety by avoiding and/or purging food; the other expresses her food obsession/severe anxiety by binging without purging.

They have identical genetic tendencies, but express them in a superficially "opposite" response due to different environmen­t/experien­ces.

The anorexic sister may be obsessed with thinness due to one or more personal humiliations around weight as a young girl. For example, she aspired to be friends with a very popular girl at school who was hyper-critical and sarcastic about anyone who was "fat" -- even normal-weight children she deemed "fat".

Meanwhile, her obese sister had different life-experiences and isn't obsessed with thinness, she's obsessed with being a "good mother" and with baking lots of "treats" to show that she's a "good mother" because she took to heart such advice from a favorite grandmother who died when the obese sister was at a very impressionable age.

BOTH ended up obsessed with food/eating as a way of coping with their severe anxiety -- but this obsession manifests itself in superficially opposite ways. One starves herself to silence the inner critic; the other gorges herself to momentarily recreate the comfort and safety she lost when grandma died.

The same anxiety, the same tendency towards obsession, the same unbalanced brain chemicals that leave them both feeling tense, rudderless, frightened and stressed can be "self-medicated" in seemingly opposite ways.