Describe the biological explanations of schizophrenia 10 marks
Dopamine A01
Point
The initial - Suggested that an imbalance of dopamine activity is the cause of schizophrenia.
dopamine - There are 5 main dopamine receptor cells 1-5 (receptors 1 and 2 are the most involved in
hypothesis sz)
- (hyperactivity) Too high levels (activity of dopamine 2 receptor cells) leads to the
development of positive symptoms (such as hallucinations)
- Hypoactivity of dopamine 1 receptors ( too low activity) leads to the development of
negative symptoms (poverty of speech)
The advanced - Was modified in order to incorporate the limbic and cortical brain pathways.
dopamine - The mesolimbic pathway is linked to high activity of dopamine 2 receptors. This includes
hypothesis areas of the brain such as the Broca area, which is responsible for processing and
understanding speech.
- This can lead to the development of auditory hallucinations such as hearing the voice of
their dead relatives.
- The mesocortical pathway is linked to low activity of dopamine 1 receptors. This includes
areas of the brain such as the prefrontal cortex, which is responsible for the regulation of
emotions.
- This can lead to the development of negative symptoms such as the flattening
effect(anhedonia), this is where the sz does not display or feel any emotions such as being
happy.
Research from - Griffith conducted research on non-schizophrenia participants, who had no family history of
Griffith developing any psychological disorders.
- He gave dextroamphetamine (a drug that is used to increase the activity of dopamine in the
brain
- This lead to the participants developing positive symptoms such as hallucinations and
delusions
- Believed that if the pp’s were given a drug that lowers the activity of dopamine receptors it
would remove the positive symptoms.
Phenothiazine - A type of conventional neuroleptic that has been developed in order to decrease the levels
of dopamine 2 receptor cells in order to reduce positive symptoms. Has proven to be 75%
effective at reducing symptoms.
Only needed if doing 1 for 10 marks
Cannabis A01
Point
What is THC - Tetrahydrocannabinol
What is skunk - A modified form of cannabis that contains around 20-30% THC (compared to normal
cannabis which contains up to (5-10%)
- Is grown under strong white lights in order to be sold by individuals for recreational sale.
How does - The THC in skunk and cannabis binds to the cannabinol receptor cells (CBD) which are all
cannabis over the brain and body
increase the - This releases the delta 9 receptor cells which are responsible for the psychoactive functions
risk of and the feeling of being high.
Dopamine A01
Point
The initial - Suggested that an imbalance of dopamine activity is the cause of schizophrenia.
dopamine - There are 5 main dopamine receptor cells 1-5 (receptors 1 and 2 are the most involved in
hypothesis sz)
- (hyperactivity) Too high levels (activity of dopamine 2 receptor cells) leads to the
development of positive symptoms (such as hallucinations)
- Hypoactivity of dopamine 1 receptors ( too low activity) leads to the development of
negative symptoms (poverty of speech)
The advanced - Was modified in order to incorporate the limbic and cortical brain pathways.
dopamine - The mesolimbic pathway is linked to high activity of dopamine 2 receptors. This includes
hypothesis areas of the brain such as the Broca area, which is responsible for processing and
understanding speech.
- This can lead to the development of auditory hallucinations such as hearing the voice of
their dead relatives.
- The mesocortical pathway is linked to low activity of dopamine 1 receptors. This includes
areas of the brain such as the prefrontal cortex, which is responsible for the regulation of
emotions.
- This can lead to the development of negative symptoms such as the flattening
effect(anhedonia), this is where the sz does not display or feel any emotions such as being
happy.
Research from - Griffith conducted research on non-schizophrenia participants, who had no family history of
Griffith developing any psychological disorders.
- He gave dextroamphetamine (a drug that is used to increase the activity of dopamine in the
brain
- This lead to the participants developing positive symptoms such as hallucinations and
delusions
- Believed that if the pp’s were given a drug that lowers the activity of dopamine receptors it
would remove the positive symptoms.
Phenothiazine - A type of conventional neuroleptic that has been developed in order to decrease the levels
of dopamine 2 receptor cells in order to reduce positive symptoms. Has proven to be 75%
effective at reducing symptoms.
Only needed if doing 1 for 10 marks
Cannabis A01
Point
What is THC - Tetrahydrocannabinol
What is skunk - A modified form of cannabis that contains around 20-30% THC (compared to normal
cannabis which contains up to (5-10%)
- Is grown under strong white lights in order to be sold by individuals for recreational sale.
How does - The THC in skunk and cannabis binds to the cannabinol receptor cells (CBD) which are all
cannabis over the brain and body
increase the - This releases the delta 9 receptor cells which are responsible for the psychoactive functions
risk of and the feeling of being high.
