By Daniel Nettle and Helen Clegg Presented by Grant and Brooke.
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Transcript of By Daniel Nettle and Helen Clegg Presented by Grant and Brooke.
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