Darwanian medicine: Evol psych

Question 1

What are the 6 explanations of why we are vulnerable to mental disorders?

Answer 1

1. Evolutionary mismatch
2. Coevolutions and arms race
3. Trade offs
4. Constraints
5. Selection favours reproductive success not health
6. Selection shape defensive mechanisms that may be distressing

Question 2

Explain how evolutionary mismatch lead to our vulnerability to mental disorders.

Answer 2

Modern environment filled with novel input -> this leads to environment chronically inducing stress -> chronic stress interact with other evolutionary mismatches to cause immune dysfunciton, chronic dieases and other psychological disturbance -> yet we are dependent on these novel features e.g. social media or alcohol to cope with chronic stress –> vicious cycle

Question 3

Explain how coevolution and arms races led us to be more vulnerable to mental disorders.

Answer 3

Arms race: Evolution of pathogens e.g. virus, bacteria, parasites faster than human evolution (natural selection) + human innovation (antibiotics, vaccinnes)

Coevolution: Coevolution within species -> increasing leves of competition inter & intra -> selection favour more extreme traits (higher freq and intensity of output) -> esp if they lead to winning social compeition

e.g. Intense sexual selection pressure give rise to increase status enhancing efforts -> result in rise in envy + -ve emotions when efforts fails

Question 4

Explain how trade-offs lead to us being more vulnerable to mental disorders.

Answer 4

Trade offs are inherent to every system -> some trade offs are just more likely to result in vulnerability to disorders
- evovled psych mech for benefit outcomes can lead to distressing experience e.g. prosocial + cooperation –> guilt, social anxiety

trade off favoured as long as benefits outweighs the cost

Question 5

How does constraints lead to us being more vulnerable to mental disorders.

Answer 5

Traits and characteristics shaped by natural selections are subjected to evolutionary constraints esp. path dependence

Path dependence: process where past events limit future variations -> evolution can only incrementally modify designs via natural selection cannot radically reshape designs

Question 6

How does selection favouring reproductive success lead to us being vulnerable to mental disordes?

Answer 6

Genes will propagate regardless of one’s health, longevity or wellbeing as long as an individual possess characteristics that aid reproductive success
e.g. jealously + obsession are functional symptoms of disorders such as depression, addiction

Question 7

How does selection shaping defensive mechanisms lead to us being vulnerable to mental disorders?

Answer 7

Pain, cough , fever → protective features are unpleasant but useful to signal hazards and pathogens

Evolved psych mech induce distress → to prevent strategic interference
- Negative emotions function to draw attention to interfering events, alert individuals to the interferences, mark the events for storage and retrieval from memory and motivate action to eliminate or avoid interference

e.g. Fear and phobias