This is a summary of a lecture given on 22 Oct 2005 to 20 psychiatrists in Leichhardt Sydney as the  dinner lecture component of a half-day inaugural seminar entitled "Why Evolutionary Psychiatry" sponsored by the Evolutionary Psychiatry Special Interest Group,  St John of God Health Services, AstraZeneca and Wyeth. 
Why is the mind so badly designed?

 
Contents

Why use a Darwinian lens in Psychiatry?

Why isn't the mind better designed?

The Paradigmatic Failure of Psychiatry

DSM?

Two kinds of explanation essential

Reductionist approaches miss half the story

The Four Areas of Biology

What might evolutionary approaches add?

 

Through the Darwinian looking glass…

What are brains for?

Why did we grow brains?

The evolutionary explanation for brains

Natural Selection

Principles

Cellular instincts

Rock paintings

Commitment

 

Normal minds – evolutionary psychology

Darwin’s view on emotions

What are emotions?

Who do emotions benefit?

Overlapping disciplines

The Traditional Social Science Model of the Mind

The Massive Modularity Hypothesis

The Swiss-army knife model of cognition

A Social Module?

Theory-of-mind module dysfunction

Archetypal propensities

Archetypes

Biosocial goals

Archetypal Systems

Situations evoking anxiety as a defense

Startle may activate the Fight or Flight Program

Introducing a two-edge sword

The Smoke-Detector Principle

Situations Causing Depressed Mood

Is Depression an Adaptation?

Loss of rank & resources

Brain mechanism connecting mood & status

 

Evolutionary Classifications in Psychiatry

Causes of mental disorders?

My evolutionary classification!

1. Disorders of Malfunction

Schizophrenia

Bipolar Disorder

2. Disorders of Dysfunction (Environmental trauma or uniqueness)

Psychopathology due to Archetype Disorders

Stages in loss of attachment

Why do archetypes fail?

3. Disorders of Sociability

Disorders of Memes

What determines human behaviour?

Mimetic Lexicon 

Any evidence that memes cause harm?

 

Why use a Darwinian lens in Psychiatry?

 

Why isn't the mind better designed?

 

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DALYs Western Females 18-45 yo (WHO)

 

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Victorian Burden of Disease Study: Incident YLD rates per 1000 population by mental disorder

 

Why isn't the mind better designed?

Vast prevalence

Huge comorbidity

Onset at age of peak health

Huge fitness costs

Waxing & waning courses

 

This is an evolutionary question requiring evolutionary explanations

 

The Paradigmatic Failure of Psychiatry

Focus on physical diseases

Descriptive classifications (Kraeplin, Bleuler, Maudsley)

Psychoanalytic model

Behavioural model

Descriptive non-aetiological classifications (DSM)

Biomedical model: biological reductionism

 

DSM?

Essential in allowing researchers to study comparable groups

Widely criticised for:

Lacking a foundation in theory 

Encouraging simplistic thinking of psychiatric syndromes as discrete diseases 

(Kendell, 1984)

Neglecting maladaptive psychological processes

 

Why isn't the mind better designed?

This is an evolutionary question requiring evolutionary explanations

 

Two kinds of explanation essential

"No biological problem is solved until both the proximate & evolutionary causation has been elucidated. The study of evolutionary causes is as legitimate a part of biology as is the study of the usually physico-chemical proximate causes."

E Mayr, 1982 (The Growth of Biological Thought)

 

Reductionist approaches miss half the story

Most research attempts to explain “what” & “how”

Evolutionary approaches examine “why” we are susceptible by considering the design characteristics

Proximate & Evolutionary explanations are not competitors, but two halves of a whole 

 

The Four Areas of Biology

 

The four areas of Biology

Two objects of explanation

Development of species

Single species form

Two questions

Proximate

Ontogeny Mechanism

Evolutionary

Phylogeny Adaptation

 

(Nesse, 2000; adapted form Tinbergen, Mayr and others)

 

What might evolutionary approaches add?

Causal hypotheses

Integration of prevailing models into a framework

A theory of environment-behaviour-gene interactions

A theory of behaviour, motivations & function 

An evolutionary classification?

A non-judgmental, normalising, humanising explanatory model for patients

 

Through the Darwinian looking glass…

 

What are brains for?

Why did we grow brains?

 

…all the corporeal & mental organs …have been developed through natural selection, or the survival of the fittest, together with use or habit...

Charles Darwin, 1876

 

We are built as gene (replication) machines …

Richard Dawkins, 1978 (The Selfish Gene)

 

 

The evolutionary explanation for brains

 

…our brains have evolved to make decisions that enhance reproductive success
Michael Gazzaniga, cognitive neuroscientist

 

 

Natural Selection

Refers to differential survival of traits

Genetic variations in traits affect reproductive success 

An individual may acquire a propensity that makes him better adapted than his peers in surviving & passing on genes

Over generations, that attribute will become established as a standard component in the species genome

 

Principles

NS shapes bodies to maximise reproduction at the expense of health

NS shapes traits to ensure transmission of genes – too bad for the species

Genetic disease results mainly from quirks that were harmless in the Paleolithic

NS continues after menopause via kin selection

 

Cellular instincts

Escalation
Acquisition
Inaction
Engagement
De-escalation
Avoidance/ withdrawal/ disengagement
Attack
Self-defence

 

Rock paintings

Food acquisition

Cooperation

Inclusive fitness

Inclusive fitness

Tribal bonding

Reciprocal altruism

Conflict over resources

Self defence

 

Commitment

 

An act or signal that gives up options to influence someone’s behaviour by changing incentives or expectations

It changes behaviour by giving up options and changing beliefs

Lots of examples, main distinction is how they are enforced

Randolph Nesse, 2001 (Evolution & the capacity for commitment)

 

Normal minds – evolutionary psychology

 

Darwin’s view on emotions

Pleasurable sensations … stimulate the whole system to increased action. 

Hence it has come to pass that most or all sentient beings have been developed in such a manner, through natural selection, that pleasurable sensations serve as their habitual guides. 

But pain or suffering… lessens the power of action, yet is well adapted to make a creature guard itself against any great or sudden evil. 

…if long continued, causes depression

(Darwin Francis (ed.), The Life and Letters of Charles Darwin, 1887)

 

What are emotions?

“Adaptations” shaped by Natural Selection

Each emotion is a specialised state that adjusts cognition, physiology, subjective experience & behaviour so that the organism can respond effectively in a particular kind of situation

Positive & negative emotions are derived from the two types of basic arousal

 

Who do emotions benefit?

Our ancestors faced many more kinds of threats than opportunities, as reflected by the fact that twice as many words describe negative as positive emotions!

The emotions were “designed not to promote the happiness & survival of the individual, but to favour maximum transmission of the controlling genes.”

(EO Wilson)

"People, like all other organisms, are not evolved to maximise health, wealth, happiness or any other trait – but to have descendants, which is the continuation of life."  

(Chisholm, 1999)

 

Overlapping disciplines

Sociobiology/Behavioural Ecology

Ethological Models

Evo Psych (Cognitive) Models

Psychiatric Models

Neuroscientific models 

Archaeological Models

Anthropological Models Philosophical Models

 

The Traditional Social Science Model of the Mind

Blank slate / “Cupboard love” theory = Behaviour is the result of classical conditioning

General purpose computer

Learning

Culture

 

The Massive Modularity Hypothesis

In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation." 

(Darwin: Origin of Species, 1859)

 

“Human nature” refers to the accumulated specialized neural circuits that are common to every member of a species and are the product of that species' evolutionary history

Our modern skulls house a stone age mind 

(Leda Cosmides & John Tooby, 1997)

 

The Swiss-army knife model of cognition

The view of the mind as containing a whole suite of modular psychological adaptations
corresponding to functional components of the CNS solving particular past reproductive problems 

Each blade represents pre-programmed algorithms sensitise the organism to monitor specific situations 

biases to learn certain behavioural responses

(Leda Cosmides & John Tooby, 1997)

 

A Social Module?

Social cognition: information processing that contributes to the correct perception of dispositions & intentions of other individuals

Theory-of-Mind: inferring mental states of others 

(Martin Brune, 2001)

Group cooperation (reciprocal altruism) requires cheater detection algorithms 

(Trivers, 1971)

The Social Brain Hypothesis: Vol. of non-visual neocortex correlates with group size & length of juvenile period 

(Dunbar, 1998)

 

Theory-of-mind module dysfunction

All perform worse on ToM tasks:

Autism

Aspergers

SCZ (acute episodes)

Pathological mind-reading inferences

Intentions of others perceived as negatively related to self

Pathological egocentrism

 

Archetypal propensities

Natural selection has equipped us with lifespan-specific, context-sensitive archetypal propensities to navigate biosocial imperatives that facilitate inclusive fitness.

Genes are conveyers of potential for species-characteristic behaviours, rather than rigid determinants of social behaviour.

(Stevens & Price, 2000)

 

Archetypes

Human “instinct” 

(William James, Principles of Psychology, 1890)

“Collective unconscious” 

(CG Jung)

Mother-infant instinct 

(Bowlby, 1958)

 

Biosocial goals

  1. Defense (fight or flight) 

  2. Attachment

  3. Dominance-striving

  4. Reproduction

(Gardiner, 1988)

 

Archetypal Systems

  1. The stranger archetype

  2. The affiliation and bonding archetype 

  3. The hierarchical ranking dominance-submission archetype

  4. The courtship & mating archetype

(Stevens & Price, 2000)

 

Situations evoking anxiety as a defense

Harm from strange humans --> Stranger anxiety 

Separation from carer --> Separation anxiety 

Threats to status/group membership --> Social anxiety 

Socially unaccepted impulses --> Obsessive self-doubt

Lack of food or other resources --> Obsessive hoarding

Getting sick --> Hypochondriasis/Obsessive cleanliness

Dangerous small animals --> Small animal phobias 

Potential attack to family members --> General anxiety 

Imminent attack by predator --> Panic

Environment in which attack is likely --> Agoraphobia 

(Adapted from Nesse, 1990)

 

Startle may activate the Fight or Flight Program

… to motivate to urgent action

for survival

…to respond to Danger…

…with Fight …

… Or Flight …

(Walter Cannon, 1929)

 

Introducing a two-edge sword

Lungs: blood O2
Heart: O2 blood delivery
Muscles: O2 metabolism
GIT: bld flow to gut
Brain: activation of fear circuitry
Lungs: SOB, choking, parasthesia 
Heart: Palps, chest pain, flushes
Muscles: Trembling, tension, sweating 
GIT: Dry mouth, butterflies, nausea, belching
Brain: Dizziness, faintness, lightheadedness, catastrophic cognitions & fear

 

The Smoke-Detector Principle

Anxiety is a useful defence

…but it uses extra calories, makes us less fit for everyday activities & damages tissues

So why is it so readily triggered?

Because the cost of getting killed even once is enormously higher than the cost of responding to 100 false alarms

 

Situations Causing Depressed Mood

Loss of attachment – carer, mate (Bowlby, 1969)

Loss of rank – social status (Stevens & Price, 2000)

Loss of resources  (Nesse, 2000)

Internal 

Trauma

Bodily damage 

External

Bad decisions e.g. wasted effort pursuing risky goals 

Disruption to major life goals and enterprises

 

Is Depression an Adaptation?

Communicate (Darwin, 1872) need for help

Signal yielding in hierarchy conflict

Disengage from unreachable goals

Regulate patterns of investment

(Nesse, AGP, 2000)

 

Loss of rank & resources

Social Competition Hypothesis of Depression

Agonistic behaviour was principal form of social competition underlying sexual selection

Involuntary subordinate strategy functions to:

Inhibit aggression towards rivals

Acceptance of outcome through yielding preserves the loser

Signal submission: ‘no threat’ to rivals as ‘out of action” 

Loss of resource holding potential (self esteem) can cause depression

(Price, Sloman, Gardner, Gilbert, Rohde, BJP, 1994)

 

Brain mechanism connecting mood & status

Serotonin (5HT) in a-male (highest ranking) vervet monkeys 2x other males

When lost their position: appeared depressed (huddled, rocked, refused food) & dropped 5HT levels

Depressed behaviour prevented by Prozac, which raised 5HT

If removed a-male & gave Prozac to random male, that male became a every time

(Raleigh & McGuire, )

 

 

 

Evolutionary Classifications in Psychiatry

 

Causes of mental disorders?

  1. Primary brain abnormalities 

  2. Environmental trauma or uniqueness

  3. Byproducts (Adaptive but distressing)

(adapted from Nesse RM, 1991)

My evolutionary classification!

 

A) Structural classification

 

1. Disorders of Malfunction 

 

Differentiation - Mental disorders that result from localised (modular) brain malfunction due to genetic vulnerability or injuries of the developing central nervous system 

Integration - Mental disorders that result from NON-localised brain malfunction due to genetic vulnerability or injuries of the developing central nervous system 

 

2. Disorders of Dysfunction  - Mental disorders that result from dysregulation of adaptive responses leading to failure to achieve specific biosocial goals of the entire organism

 

Environmental uniqueness 

Maladaptive memes 

 

3. Disorders of Sociability - Mental disorders due to behaviours causing severe subjective or  objective distress and negative/harmful social consequences

 

(adapted from Nesse & Williams, 1996; Nesse R, 1999)

B) Functional classification

 

Archetype disorders - Mental disorders may result from failure to meet biosocial imperatives (goals or social roles) by archetypal propensities (lifespan-specific context-sensitive propensities for behaviours that facilitate inclusive fitness) 

 

Disorders of the Attachment Archetype 

 

Disorders of the Hierarchical Ranking Archetype 

 

Disorders of the Courtship & Mating Archetype 

 

Disorders of the Threat Response Archetype

 

(Adapted from Stevens & Price, 2000; Gardiner, 1988)

1. Disorders of Malfunction

Caused by genetic abnormalities, infection, toxins, developmental factors

Result in:

Malfunction (e.g. SCZ, autism, learning disorders, dementia), or 

Dysregulation of the expression of adaptive responses (e.g. melancholia, BPAD)

 

Schizophrenia

What can account for a high incidence of genes that can decrease fitness?

Predisposing genes advantageous in combo with other genes or in certain environments

Other effects that offer slight advantage in most carriers

e.g. mind-reading capacity, protect against a disease (like SCA), suspiciousness, creativity, leadership potential ? group splitting ?

 

Bipolar Disorder

Extreme or pathological combinations of hyperthymic /cyclothymic / irritability personality traits 

Achievement & creativity are evident in bipolar patients b/w acute episodes (Andreasen) & non-ill relatives

Music, performing arts & poetry may have evolved by sexual selection

Leadership traits: face challenges, increase group stability

Risk-taking & exploration

(Akiskal, 2000)

 

2. Disorders of Dysfunction (Environmental trauma or uniqueness)

Normal brain mechanisms but imperfection of evolved mind programs

Exposure to novel environmental circumstances, idiosyncratic learning histories or trauma 

Examples: some anxiety & depressive disorders, addictions, fetishes

 

Psychopathology due to Archetype Disorders

Mental disorders the result of “frustration of archetypal intent” 

(Stevens, 1982)

Developmental view

Comorbidity due to failure of early biosocial imperative (upstream block) undermining downstream archetypal intents

 

Stages in loss of attachment

Protest: anxiety

Despair: Grief/Depression 

Detachment : Defensiveness/self-reliance/poor sociability/personality dysfunction

(Bowlby, 1969)

 

Why do archetypes fail?

Genome lag hypothesis: mismatch b/w current environment & traits selected by the past (EEA)

Because of past evolutionary compromises & trade offs organisms are not optimally designed 
the target of selection is the whole organism not individual traits

(McGuire & Troisi, 1998)

 

3. Disorders of Sociability

Patterns of emotion or behaviour that are painful or socially unacceptable, but nonetheless adaptive 

Examples: 

Sexual infidelity

Shyness

Homicide due to male status striving; failure to attach to an adopted baby; abuse & infanticide in stepparents (Daly & Wilson, Homicide, 1988)

 

 

 

 

Disorders of Memes

 

 

What determines human behaviour?

We are built as gene machines & cultured as meme machines

Richard Dawkins, 1978 (The Selfish Gene)

The Invasion of human brains by culture, in the form of memes, has created human minds. 

Daniel Dennett, 1995

 

Mimetic Lexicon

http://pespmc1.vub.ac.be/MEMLEX.html

 

meme

(pron. `meem') A contagious information pattern that replicates by parasitically infecting human minds and altering their behavior, causing them to propagate the pattern. (Term coined by Dawkins, by analogy with "gene".) Individual slogans, catch-phrases, melodies, icons, inventions, and fashions are typical memes. An idea or information pattern is not a meme until it causes someone to replicate it, to repeat it to someone else. All transmitted knowledge is memetic. (Wheelis, quoted in Hofstadter.) (See meme-complex).

 

meme-complex 

A set of mutually-assisting memes which have co-evolved a symbiotic relationship. Religious and political dogmas, social movements, artistic styles, traditions and customs, chain letters, paradigms, languages, etc. are meme-complexes. Also called an m-plex, or scheme (Hofstadter). Types of co-memes commonly found in a scheme are called the: bait; hook; threat; and vaccime. A successful scheme commonly has certain attributes: wide scope (a paradigm that explains much); opportunity for the carriers to participate and contribute; conviction of its self-evident truth (carries Authority); offers order and a sense of place, helping to stave off the dread of meaninglessness. (Wheelis, quoted by Hofstadter.) 

 

exo-toxic

Dangerous to others. Highly exo-toxic memes promote the destruction of persons other than their hosts, particularly those who are carriers of rival memes. (Such as: Nazism, the Inquisition, Pol Pot.) (See meme-allergy.) (GMG)

 

mimicry

An infection strategy in which a meme attempts to imitate the semiotics of another successful meme. Such as: pseudo-science (Creationism, UFOlogy); pseudo-rebelliousness (Heavy Metal); subversion by forgery (Situationist detournement). (GMG)

 

memeoid, or memoid

A person "whose behavior is so strongly influenced by a [meme] that their own survival becomes inconsequential in their own minds." (Henson) (Such as: Kamikazes, Shiite terrorists, Jim Jones followers, any military personnel). hosts and membots are not necessarily memeoids. (See auto-toxic; exo-toxic.)

 

cult

A sociotype of an auto-toxic meme-complex, composed of membots and/or memeoids. (GMG) Characteristics of cults include: self-isolation of the infected group (or at least new recruits); brainwashing by repetitive exposure (inducing dependent mental states); genetic functions discouraged (through celibacy, sterilization, devalued family) in favor of replication (proselytizing); and leader-worship ("personality cult"). (Henson.)

 

Any evidence that memes cause harm?

Can memes cause harm?

N=39,000 in 9 studies, in 5 global locations ? youth more likely to have had MDEs than their elders, especially in higher economic devt

Mass communications ? inc comp., unreachable goals

New technology ? disintegration of families & communities 

 


More information:

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This information is intended for education purposes by health professionals and should not be used as a substitute for any health professionals' individual advice and treatment.  Every patient needs to be treated as an individual and individual requirements may differ from general guidelines or principles like those suggested below. 

 

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