Disorders

1. Disorders Psychology 3906

2. Introduction • You probably didn’t think you could use evolutionary theory to explain disorders • Well you’re wrong! • It does not make these things any less problematic than they are if we can understand the evolutionary underpinnings • This work is in its infancy

3. Possible evolutionary explanations • Some diorders may be defenses • Side effects of fitness enhancing genes • Frequency dependent selection • Absence or malfunctioning of a module • EEA and now • Extremes of plygenetic traits

4. PTSD • Should be more common in man made situations • It is • Ahh but there was always warfare • But not with the type of weapons we have today

5. Depression • Not just feeling down • Length and severity are key • Feelings of worthlessness • Lack of motivation

6. Is it adaptive? • Nesse’s idea • Telling us we are going the wrong way so to speak • Don’t expend resources, energy on stuff that won’t work • You can see the adaptiveness here • But you have to bounce back

7. Depression threshold • Idea that when you ‘lose’ you feel bad • You slow down then • Maybe some people have way to low a depression threshold? • Perhaps some have one that is too high too, not been really looked at

8. Is this a good explanation? • Well depressed people may actually be a tad more accurate than non depressed! • SAD • Female vs. male differences in depression

9. Why is depression so common? • EEA vs. today disconnect • Number of relatives close by • Jobs • Power is not visible • We compare ourselves to athletes, movie stars etc

10. Maybe depression is negotiation! • Get help from kin, even though now they are not around • Explains postpartum depression nicely • New idea

11. suicide • Hmm • Not group selection • Kin selection • Suicide notes reflect this, that people feel they are a burden etc

12. Anxiety disorders • Phobias for example • Phobias seem to be learned • However, nobody is afraid of houses or cars • They are afraid of sharks and snakes • People are afraid of flying, not of airplanes overhead, even if they have been through bombing

13. sociopaths • Eww • Might actually be a reproductive strategy, but only successful if rare • Little shame or guilt • Playing on reciprocal altruism • Maybe give them an ‘outlet’

14. Autism Specrtum Disorders • Characterized by a lack of social interaction, or poor interaction • Repetitive beahviour • Fixation on some characteristic or thing • Many retarded, but not all (indeed the percentage seems to be going down in a way)

15. What is the evolutionary argument here? • Theory of mind module • ‘hyper male’ brain • Kids of scientists are more likely to be autistic • Boys are much more likely to be autistic than girls

16. Schizophrenia • Does creativity go with Schizophrenia? • Maybe not • However, they have more creative relatives! • Might be some relationship there

17. Conclusions • This is early days but promising • May lead to treatments • Does not make it ‘all in the head’ or ‘normal’ or frankly better (morally) to be normal