Schizotypy, Creativity, and Mating Success in Humans

By Daniel Nettle and Helen Clegg

Presented by Grant and Brooke

Schizophrenia

1% of the population across cultures

Heritable

Drastically reduced reproduction

Puzzle

Too frequent to be a mutation

Natural selection has not eliminated schizophrenia

Is there a beneficial effect of the traits?

Schizotypy: Not all Bad

Continuum of personality experience ranging from normal dissociative, imaginative states to extreme states related to psychosis  

More schizotypy does not mean more ill Linked to academic achievement and

creativity  Negative effects may remain dormant

unless triggered by environment

Schizotypy

Traits measured on 4 dimensions High scores predict the onset of

schizophrenia Schizophrenic patients score high on

all 4 dimensions Bipolar patients score high on 3

dimensions

Elevated Schizotypal Traits in the Creative Arts

High incidence of serious psychiatric illness in families of artists

Many studies found that individuals active in creative arts have elevated levels of some schizotypy traits

Is artistic creativity the evolutionarily beneficial effect of schizotypy?

Condition Dependent Fitness Indicator

Geoffrey Miller’s hypothesis of costly displays of quality whose function is to attract mates

Prediction: artistic production correlated with high number/quality of sexual partners

4 Dimensions of Schizotypy

Unusual experiences: magical thinking/perceptual

Cognitive disorganization: poor concentration

Impulsive non-conformity: reckless behaviors

Introvertive anhedonia: lack of enjoyment/social withdrawal

Previous Findings

Unusual experiences and impulsive non-conformity elevated in poets and artists

Introvertive anhedonia positively associated with schizophrenia, but negatively associated with artistic creativity

Predictions

Higher schizotypy traits of artists (unusual experiences and impulsive non-conformity) should increase number of sexual partners

Increase in sexual partners should operate through artistic production

Schizotypy that is characteristic of schizophrenics (introvertive anhedonia) should be negatively correlated with mating success

Current study

Examines the relationship between schizotypy and mating success

The sample looks at the general adult population augmented by targeted sampling of artists and poets

The sample is not representative of the population; it is specifically designed to produce a full range of schizotypy scores in a non-clinical context

4 Schizotypy Dimensions Defined

Unusual experiences contains items referring to perceptual and cognitive aberrations and magical thinking

Cognitive disorganization describes difficulties of attention and concentration

Impulsive non-conformity refers to violent and reckless behaviors

Introvertive anhedonia measures lack of enjoyment and social withdrawal

Participants

Participants were 425 British adults (256 male, 269 female), average age of 40.5 years with standard deviation of 14.5 years

Participants received a gift card for participation Recruited people from the general population

using online advertisement, questionnaire packs, and mature psychology students

Recruited specialist creative groups via advertisement in visual art magazine, poetry website, and by writing directly to published poets

100 more people heard about the study and indicated their interest to participate

Tests

Participants filled out the O-LIFE schizotypy inventory and a section on psychiatric history

Also filled out a section regarding creative interests and participants indicated their degree of creative activity in poetry or visual art

Participants rated selves as not producing poetry or art (241), hobby producer (57), serious producer (60), professional producer (67) in either domain

A final section of the questionnaire contained wide-ranging personal history questions that asked for information on mating success (reproductive success was defined as greater number of partners)

Results: Unusual Experiences Are your thoughts

sometimes so strong you can almost hear them?

Have you ever felt you have special, almost magical powers?

Is your hearing sometimes so sensitive that ordinary sounds become uncomfortable?

Are you so good at controlling others that it sometimes scares you?

Does it often happen that nearly every thought immediately and automatically suggests an enormous number of ideas?

Results: Impulsive Nonconformity

Do you ever have the urge to break or smash things?

Do you often feel like doing the opposite of what people suggest, even though you know they are right?

Would you take drugs which may have strange or dangerous effects?

Have you ever taken advantage of anyone?

Results: Introvertive Anhedonia Do you find it difficult

to feel very close to your friends?

Are you much too independent to really get involved with people?

Are people usually better off if they stay aloof from emotional involvements with people?

Do you have trouble letting yourself go and enjoying yourself at a lively party?

Results: Cognitive Disorganization

Are you sometimes so nervous that you are blocked?

Do you ever feel that your speech is difficult to understand because the words are all mixed up?

No matter how hard you try to concentrate do unrelated thoughts always creep into your mind?

Do you often feel "fed up"? Are you easily hurt when

people find fault with you or the work you do?

Results: Number of Partners vs. 4 Dimensions

Multiple regression analysis

Independent variables: 4 dimensions, age, sex, social class

Dependent variable: number of partners

Results

Results

PREDICTION: If schizotypy increased mating success, it would do so through enhancing creative behavior

RESULTS: Number of partners and level of engagement with poetry and visual arts 

Results

PATH ANALYSIS

Linkages among creative behavior, mating success and 3 dimensions

Cognitive disorganization left out because no significant relationship with creative activity or mating success

Discussion

The results are consistent with Miller’s hypothesis that artistic creativity functions as a mating display

Schizophrenia patients are also high in unusual experiences and impulsive non-conformity

These results are consistent with the view that schizotypal traits are maintaied in the human population at significant levels because the negative effects of psychosis are offset by enhanced mating success

When is it too much?

Impulsive non-conformity can enhance mating success due to the reckless behavior (direct benefit)

Unusual experiences can manifest as enhanced creativity (indirect benefit)

Schizotypal Traits

Mati

ng S

ucc

ess

But recent evidence suggests a different model…

The Difference between Artists and Schizoprenics

Poets and artists score as highly on unusual experiences and impulsive non-conformity as schizophrenic patients do

The difference is that poets and artists do not score as high on the introvertive anhedonia

Suggests that individuals in good condition can channel odd experiences and impulses into creative output and adaptive behaviors, while those in poor condition develop psychiatric disorders

The Deciding Factor…

Introvertive anhedonia appears to be the critical condition-related dimension that differentiates between the positive and negative sequelae of schizotypal traits

Art, Poetry, and Sex

There were no observed sex differences in the relationships between creative output and reproductive success

Results show that when either sex invests in creative output, it has similar effects on mating success

Conclusions

Mate choice is linked to creativity, creativity to schizotypy, and schizotypy to schizophrenia

Criticisms

Measurement of mating success is number of partners

Never look at quality of partners Present day results may not relate to EEA Pattern is the same for male and female artists,

counter to condition dependent fitness hypothesis

Quality of creative work produced never assessed

People may misrepresent how often they produce creative work