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Starting June 1, I will tweet a chapter each day from my new book goodreasons.info about how the light of evolutionary biology can dissolve the mists that swirl around mental disorders. Well, some mists for some disorders. @DuttonBooks @hbes2019 @LondonEvolution @ISEMPH
From the Preface: I wanted to write this book as soon as I realized that evolution could explain why bodies are vulnerable to disease. But the rest of medicine had to come first. Why We Get Sick stirred lots of interest. The new book is about why mental illness exists at all.
For each chapter I address the question, "So what?" Saying what is true changes only views unless it also changes what people do. Mental health clinicians who understand evolution do their work differently and better. For all others, self-understanding is valuable in itself.
No time to read the whole book? goodreasons.info Waiting for the paperback? Here are pithy summaries of 14 chapters, one per day, June 1-14.
@APAPsychiatric @APA @ISEMPH @LondonEvolution @DuttonBooks @evmedasu @evmed_ch @TriCEM_NC @AllenFrancesMD
Psychiatric treatment is effective but its main paradigm is failing. We expected to find specific genes and brain abnormalities that cause the major disorders, but 40 years of searching by thousands of smart scientists have found none. Calls for new approaches echo everywhere.
The standard approach is that of a mechanic. How does it work? What is different and broken in people who are sick? An evolutionary approach asks a fundamentally new question. "Why are we all the same in ways that make us all vulnerable?" A engineer would ask "Who designed this?"
The resulting confusion matters. My patient Ms. A was furious after getting 4 explanations from 4 experts. Neurosis? Oedipal wishes? Marital problems? Brain abnormality? An integrative framework is desperately needed.
Studies of animal behavior all ask about adaptive function as well as mechanism. The rest of medicine relies on understanding normal function to understand pathology. Evolutionary biology is psychiatry's missing foundation.
Why hasn't psychiatry incorporated evolutionary thinking decades ago? I can't understand it. Fears of creationists? Just not knowing anything about it? Trying to be very very scientific and thinking the spandels article discredited evolution? What do you think?
Psychiatric diagnosis is so confused and controversial that the NIMH gave up on the DSM. Dan Stein and I decided to see if evolution could help. We concluded that the DSM diagnoses are actually pretty good.
The problem is that a simplistic model encourages the false expectation that each disorder should have a specific simple brain cause. But what we have been looking for may not exist for most disorders. Some are symptoms, not diseases. Others are systems failures with many causes.
The so-called "medical model" in psychiatry is nothing like the model used in the rest of medicine. Evolution provides a genuinely medical model that distinguishes symptoms from diseases and understands pathology in the context of normal adaptive function.
Mutations happen and selection is limited, both for sure important. But if mutation stopped and selection worked for 1000 generations, would we all be healthy? Alas, no. There are five other reasons why we are vulnerable.
Bacteria and viruses evolve faster than we can. So, autoimmune responses --> some OCD, and inflammation --> some depression, and infection in pregnancy can disrupt brain maturation -->some schizophrenia.
All traits are tradeoffs, necessarily imperfect because improving one function disrupts another. More about this later.
Mismatch between our minds and modern environments is a big factor for drug abuse and eating disorders, not so much for other disorders that have been around before cities even existed.
The BIG explanation is that selection shapes minds to maximize reproduction, not health or happiness. So, we have drives to do things--sexual, competitive and selfish--that cause misery in the long run. As most religions have long recognized.
Finally, responses like pain, cough, anxiety and low mood exist because they are useful. Worse, they feel awful because that makes them more useful. Worse yet, they are prone to false alarms and poor regulation for good reasons.
Bottom line: All medical problems need an explanation that describes what has gone wrong, and they also need an explanation for why the trait is not more robust. There are several possible reasons and more than one can apply. These are new answers to a new question.
VSAD-Viewing Symptoms As Diseases-is the source of vast confusion. Bad feelings like anxiety and low mood seem obviously abnormal. But they are features, not flaws. Natural selection shaped them because they are useful. They are symptoms not diseases.
UNLESS the regulation mechanism goes awry. Which it often does. But even if it is normal, plenty of bad feelings are useless. Some are necessary false alarms. Others are good for our genes, too bad about our suffering.
Progress will come from giving up attempts to pin specific functions on emotions and instead asking what SITUATION each emotion is shaped to cope with.
A genuinely medical approach to emotions looks at the wonderfully diverse goals individuals pursue, and asks how things are going for each one, while also asking if related emotions are useful, normal but useless, or abnormal.
Day 5 of tweets about 14 chaps in goodreasons.info
A book about why mental disorders exist at all, and how to put psychiatry on a solid foundation
@AnxietyUK @Got_Anxiety @APAPsychiatric @DBarlow20 @ISEMPH @EHBEA1 @HumBehEvoSoc @UmEhap
Too much anxiety is a serious problem, but too little is worse. People with hypophobia are not waiting in clinics, they are in divorce courts, unemployment lines, ERs and morgues. That is one reason why most of us have so much excess anxiety.
Another reason is the Smoke Detector Principle. False alarms are cheap compared to the possibility of death if no alarm is mounted. So selection shapes the system to have many perfectly normal false alarms to ensure responses when necessary
Repeated arousal of anxiety indicates inadequate protection, often sensibly shifting the system to increased sensitivity—but at the risk of vicious circles causing anxiety disorders.
Women have far more anxiety than men. Whole books have asked what is wrong with them. An evolutionary view instead suggests that women have about the right amount of anxiety, but that men have too little because that benefits their genes.
Evolutionary understanding transformed how I treated my patients with panic disorder. When I explained that panic is a useful emergency system that is prone to false alarms, many said, "That makes sense. I will just stop worrying about it." And many did.
Recognizing that anxiety can be useful also transformed how my patients viewed their problems--from a personal failing and flaw, to having a condition that gives advantages as well as terrible disadvantages that can be overcome with treatment.
From: Good Reasons for Bad Feelings: Insights from the Frontier of Evolutionary Psychiatry goodreasons.info amazon.com/Good-Reasons-B… @Got_Anxiety @APAPsychiatric @HumBehEvoSoc @NAMICommunicate @DuttonBooks @PsychTimes @PsychToday
We will never understand abnormal depression until we understand how normal low mood is useful. Many evolutionary approaches propose specific functions for depression. A better approach is to discover the SITUATIONS in which LOW MOOD is useful.
To pick berries efficiently, motivation for picking from one bush needs to turn off when it is time to look for a new bush. This is Charnov’s famous marginal value theorem. Motivation that is too high for too long will result in hunger before long!
In propitious situations, where payoffs are big, high mood gives advantages. In unpropitious situations, where effort is wasted, low mood prevents loss and damage.
Low mood is psychic pain. Like physical pain, it gets us to stop doing things that are causing loss or damage. Depression is chronic psychic pain. Like chronic physical pain, it is useless and terrible. Why is it so common? Chapter 7 is next.
From: Good Reasons for Bad Feelings, a book about evolutionary psychiatry goodreasons.info
@NAMICommunicate @statnews @DepressionCntr @Got_Anxiety @HumBehEvoSoc @PeterDKramer @AllenFrancesMD
Ordinary low mood is like the pain caused by a broken leg. Abnormal depression is like chronic pain caused by a defective pain regulation mechanism. Mania is like an engine without a governor. Mood disorders result when the moodostat fails.
There is nothing normal or useful about psychotic depression or mania. Both are serious diseases that result from broken mood regulation mechanisms. VDAA—Viewing Diseases As Adaptations—is a serious error
But the main obstacle to progress in understanding mood disorders is VSAD—Viewing Symptoms As Diseases. Only when we study mood the way we study fever or cough will we be able to understand mood disorders.
Cybernetics is crucial to understand mood dysregulation. Depression often results from continued pursuit of an unreachable goal. Mania arises when the feedback mechanisms that mediate mood are missing.
Lifetime depression rates range from 3 percent in Japan to 17 percent in the United States. Finding out why is the most important unanswered question for mood disorders research.
Depression is caused by the situation, the view of the situation, and the brain. Treatment can change the situation, the view of the situation, and the brain. All three interact in tangled webs of causes, so addressing only one of them will miss many treatment possibilities.
From: GOOD REASONS FOR BAD FEELINGS . goodreasons.info
@egoode @RiadhAbed1 @HumBehEvoSoc @Got_Anxiety @EHBEA1 @DSTEINGIMD
Researchers look for nomothetic generalizations as if everyone in a category is the same. Clinicians create idiographic stories to try to understand how this individual came to this set of problems. Both are essential. No need to argue, listen to patients AND data, already!
In the rest of medicine doctors conduct a Review of Systems to find out what might be causing a problem. Mental health clinicians can conduct a Review of Social Systems to find problems in each of six areas.
•Social recognition and friends
•Occupation and roles people value
•Children and family
•Income and finances
•Abilities, appearance and health
•Love and sex
The best mental health clinicians understand people as individuals, AND they understand diseases as generalizations about people with similar problems. Both are essential. Evolution provides a framework for bringing idiographic data into nomothetic studies.
From: GOOD REASONS FOR BAD FEELINGS goodreasons.info
This link takes you to the whole thread
@TangledWing @PeterSinger @jbsilk1 @ISEMPH @HumBehEvoSoc @RidlrMUM @APAPsychiatric @PsychScience
Natural selection shapes organisms to do whatever is good for their genes. It makes love and goodness seem like mistakes or illusions, and that make evolutionary psychology seem amoral. Understanding how morality evolved is a crucial but missing foundation for psychiatry.
Benefits to others with the same genes explains a lot, and so does trading favors, but they can’t explain guilt and genuine goodness. Neither can benefits to the group. Cultural selection can, but it has to get started somehow. See new article by @jbsilk1 cell.com/current-biolog…
Self-interested partner choices select powerfully for goodness and empathy. People who have the best social partners do best. To get the best partners you have to be a preferred partner, and that means being thoughtful, generous, honest and good.
But the price of goodness is constant concern with pleasing others, social anxiety, low self-esteem, guilty midnight regrets and the throes of grief. Goodness and love make life worthwhile but the price can be high.
From: Good Reasons for Bad Feelings: Insights from the Frontier of Evolutionary Psychiatry goodreasons.info
@LindaBrakel @theIoPA @BritPsyCouncil @psychoanalysis_ @T_I_H_R
Attitudes towards psychodynamics are as polarized as current politics. Saying anything good about it is unacceptable in many scientific circles; I was advised to leave this chapter out. But the unconscious is real and powerful. It is also a profound mystery.
Why does the mind have a mechanism that works hard to keep certain things from consciousness? A GREAT QUESTION. Dick Alexander and Bob Trivers argued that the unconscious mainly makes people better at deceiving and manipulating others. What a cynical view!
After a year of work on the problem I concluded that they are partly right...but mostly wrong. The unconscious is better at controlling selfish impulses than fulfilling them. People too aware of all their motives have trouble.
OCD is the flip side of paranoia. People with paranoia have an unreasonable fear that someone else might harm them. People with OCD have an unreasonable fear that they might harm someone else.
Bottom line: Tendencies to objectivity may impose costs. For instance, writing about the utility of the unconscious can annoy all kinds of people.
Sex provides more problems than pleasures for many people. Huge efforts to be desirable don't guarantee a partner & sexual relationships are fraught. The partner won’t do that special thing. Or something doesn’t work. Or someone prefers another partner. Or just isn't interested.
Of all functions, sex should work well since It is the object of strong selection. But that’s the problem. Selection maximizes reproduction at enormous costs to happiness.
Every sex book has a chapter on men climaxing too soon and women too late or never. None of them ask why. It is because the system is shaped to maximize reproduction, too bad about mutual satisfaction. For the lurid details, and lots of stories, see the book.
The old question is why some people get obese. The new question is why we all are prone to obesity. The answer is simple. Being overweight was rare and relatively harmless for our ancestors, so natural selection shaped powerful protection mechanisms only against being underweight
Crash dieting sets off those mechanisms. After few days, most people lose control and gorge. That causes fear that causes renewed dieting and more gorging, in a vicious cycle. The body reacts to the erratic food intake by adjusting the weight set point upwards.
Some suggest that anorexia is an evolved strategy. Trying to be attractive yes, anorexia, no.
Others say it is a genetic disease. Vulnerability to eating disorders is influenced by genes but that does not make them genetic diseases.
Eating is just one of many desires that gets out of control when we try to control it. Trying to deny desires creates even more problems than hedonistically pursuing them, but seeking an Epicurean balance works better.
A chapter from goodreasons.info about #drugabuse #alcohol and #addiction @NIDAnews @CntrOnAddiction @delisev8 @HumBehEvoSoc @ISEMPH
The old question: why do people get addicted? The new evolutionary question: why are we all vulnerable? The answer is that natural selection has had too little time to protect us from the new ready availability of pleasure-inducing pure drugs.
Every addict starts off believing that stopping is just a matter of willpower. The illusion often proves fatal. Drugs hijack our learning mechanisms like gun-wielding terrorists in an airplane cockpit.
Smoking kills 480,000 Americans each year, alcohol 100,000, opioids 50,000. So selection will make us less vulnerable eventually. But who wants to wait scores of generations?
Some people are less vulnerable to addiction. How do their foraging patterns in a natural environment differ from those of people who are vulnerable? Finding out should make it possible to develop video games that predicts addiction.
As for a solution, education, interdiction and punishment don’t work very well. Our best hopes are to find ways to influence brains and to make everyday life more fulfilling.
And nearly the end of this very long tweet thread!
Here is the whole thread
@ISEMPH @APAPsychiatric @matthewckeller @RobertPlomin
Why hasn’t natural selection has purged the genes that cause schizophrenia, bipolar, and autism? That is a very good question.
Mutations keep occurring and getting selected out, that is for sure important. But the search for specific ones has been a crushing disappointment; no common genetic variations increase risk by more than 1%.
Do the responsible genetic variations give advantages? Many people think so, but evidence is thin for benefits as simple as intelligence or creativity.
This chapter suggests that the problem may not be just bad genes, but selection pushing some trait that gives big advantages right up to a peak near a cliff edge where fitness collapses.
Natural selection stabilizes such traits at values that leave a few percent of the population “off the cliff” and vulnerable to disease. This is the pattern we see for schizophrenia, autism, schizophrenia and many other diseases.
Tomorrow: What should we do differently?
There should be no need for evolutionary psychiatry, all psychiatry should make full use of evolutionary biology. But that will take time. This book will can help things along but only if clinicians and researchers read it. Please help with that!
Excess enthusiasm could slow progress. My book is full of new ideas, but only some of them will turn out to be correct. My fondest hope is that by asking a new question--Why are we all vulnerable to mental disorders?--the book will spur many new studies.
In the meanwhile, it provides an explanation for why life is so full of suffering for so many people...and how natural selection created creatures capable of goodness and love.

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Full info at: goodreasons.info
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