Biological Approach

Question 1

What are the three biological explanations for schizophrenia?

Answer 1

• Genetic explanation 🧬
• dopamine hypothesis brain 🧠 (neurochemical)
• neural correlates to schizophrenia

Question 2

What is the genetic explanation for schizophrenia?

Answer 2

That it is caused by polygenic sets of candidate genes

Question 3

What are candidate genes?

Answer 3

Individual genes that have direct link to genetic transmission

Question 4

What did Ripke et al (2014) find? (Genetic explanation for scizophrenia)

Answer 4

Found 108 gene sets within 37,000 schizophrenics

These genes were connected to functioning of the neurochemicals, particularly dopamine

Question 5

What did Gottesman (1991) find? 👨‍👩‍👧‍👦

Genetic explanation for scizophrenia

Answer 5

Looked at occurrence rates of scizophrenia with families….

With one biological parent having scizo, concordance rate of for children is 13%

Both parents having scizophrenia, 46%

And sibling 9%

Question 6

What did Joseph (2004) find? 👯‍♀️

Genetic explanation for schizophrenia

Answer 6

Meta analysis of all reported studies prior to 2001

Dizygotic twins had 7.4% concordance rate
👩🏼👩🏻

Monozygotic had 40.4%
👩🏼👩🏼

Question 7

What did Tienan (2004) find?

Genetic explanation for schizophrenia

Answer 7

In findland, studied 154 adoptees who’s biological mother has been diagnosed with scizophrenia. 👩‍👦

6.7% developed scizophrenia compared to control group of 194 at just 2%

Question 8

What is the dopamine hypothesis?

Answer 8

Over sensitivity to dopamine leads to frequent firing of neurons in the brain resulting in schizophrenic type symptoms 🔫

Question 9

What did synder (1974) and comer (2003) find?

Dopamine hypothesis

Answer 9

Schizophrenics have higher level of D2 reception neurons, these neurons effect perception and attention

Question 10

What did Davis et al (1991) find?

Dopamine hypothesis

Answer 10

Positive symptoms associated with high levels in MESOLIMBIC dopamine system

Negative symptoms associated with high levels in MESOCORTICAL dopamine system

Question 11

Where in the brain is HYPERdopaminergia found and what is it linked to?

Answer 11

Subcortex - Broca’s area

Speech poverty and avolation

Question 12

Where in the brain is HYPOdopaminergina found, and what is it linked to?

Answer 12

In the prefrontal cortex

Question 13

Exaplin how ‘drug research into amphetamines’ is a support for the dopamine hypothesis

Answer 13

Randup and Munkvad

Created schizophrenia in rats by giving them amphetamines 🐀

They work by stimulating dopamine causing schizophrenia episodes

This increases reliability as people to take these drugs are more controlled due to not having schizophrenia

Question 14

Explain how ‘drug research into antipsychotics’ is a support for the dopamine hypothesis 💊

Answer 14

Antipsychotics block receptors of dopamine which causes a decrease in positive symptoms

Davies et al proved this effectiveness and not placebo as patients relapsed on placebo 55% of the while treatment was 19%

Higher levels of dopamine correlate with positive symptoms

Increased reliability by adding further research

Question 15

What are neural correlates?

Answer 15

Structures in the brain that are directly correlated with a certain experience 🧠

Question 16

What part of the brain causes negative symptom ‘avolition’ ? 🧠

What is this area in control of?

And so damage would cause….

Answer 16

Ventral striatum

Anticipation of reward 🏆

A lack of motivation due to lack of anticipation

Question 17

What two parts of the brain causes positive symptom ‘hallucinations’?

And does low or high activity levels cause this?

Answer 17

Superior temporal gyrus

Anterior cingulate gyrus

Low ⬇️

Question 18

What did Allen et al find?

Neural correlates

Answer 18

Scanned the brains of patients experiencing auditory hallucinations, and compared to control group

Whilst scan took place, they had to identify prerecorded speech as theirs or others 🗣

Hallucination group made more errors and had lower activity levels in STG and ACG 🧠

Question 19

Explain how ‘biochemistry cause or effect?’ is a criticism for neural correlates.
🐔🥚

Answer 19

Is it the schizophrenia that causes the brain abnormalities, or the abnormalities that causes the schizophrenia

Lack of motivation caused by less activity in ventral striatum, or less activity in this area caused by lack of motivation?

Unclear and not controlled