Lesson 8- Biological Approach- Influence of biological structures & neurochemistry on behaviour 🏃♂ Flashcards
What are biological structures?
Biological structures- biological structures are organs (e.g. 🧠) & systems (e.g. nervous system) that influence human 🏃♂
What are the 2 main biological structures?
1) Brain
2) Nervous System & Neurons
What is the Nervous system comprised of?
Nervous System & Neurons:
- CNS (central nervous system)- consists of 🧠 & spinal cord- controls breathing & 💓 rate
- PNS (peripheral nervous system)- sends & receives messages from CNS to other parts of body
- Neurons- transmit nerve impulses in the form of electrical⚡️ signals
What is the brain comprised of?
Made up of 4 lobes- see image ➡️:
Parietal- processes info about temp, taste 👄, touch☝️ & movement
Frontal- important for cognitive 🧠 functions & control of voluntary movement/activity
Temporal- processes memories, integrating them with sensations of taste 👄 , sound 👂, sight 👀 & touch☝️
Occipital- primarily responsible for vision 👀
Cerebrum- makes up 85% of 🧠
Cerebral cortex- covers cerebrum & is responsible for high ⬆️ order thinking 🤔 & language
What are the evaluation points for biological structures as an explanation of behaviour?
👎- biological model criticised- applicable at explaining causes of some 🏃♂ BUT ✖️ others- infection of 🧠 can-> schizophrenia BUT phobias usually learnt rather than due to 🧠 malfunction
👍- study of 🧠 relies on use of scans- e.g. PET (Positron Emission Tomography) & MRI (Magnetic Resonance Imaging) & post mortem studies add to scientific 🧪 evidence- helps support biological approach- 1 of the most scientific 🧪 models/approaches when compared to 🧠 & 🏃♂ approach
👎- psychologists still ✖️ know 100% about 🧠 & its functions- … potential problems of trying to identify which part of 🧠 responsible for certain 🏃♂
👍- scientifically & objectively investigated in order to test how 🧠 structures might affect 🏃♂- e.g. use of FMRI & PET scanning gives psychologists understanding of how 🧠 functions
Why might schizophrenia develop?
Schizophrenia- might develop due to structural & functional 🧠 abnormalities
What did they do in the past to investigate patients with schizophrenia?
PAST- used post mortem’s to investigate structure of 🧠 in patients who had schizophrenia
What do they do now to investigate patients with schizophrenia?
NOW- use fMRI (Functional Magnetic Resonance Imaging)- shows images of 🧠 in action using magnetic 🧲 & radio 📻 waves
NOW- patients with schizophrenia given cognitive 🧠 & memory tasks to do- compared with normal healthy patients whilst also conducting fMRI
Which psychologist did a study about brain structure?
Brain 🧠 structure- Neural correlates- study by Swayze
What method was used for Swayze’s neural correlates brain study?
Swayze reviewed 50 studies of schizophrenic patients & examined their 🧠 imaging using MRI (Magnetic Resonance Imaging)
What were the findings for Swayze’s neural correlates brain study?
From these brain images- structure of 🧠 examined & found that schizophrenic patients’ have structural abnormalities in their 🧠 including:
- Decreased ⬇️ brain weight
- Larger ⬆️ ventricles (that are filled with water)
- Smaller ⬇️ hypothalamus
- Less ⬇️ grey matter (intelligence held here & … seems to have deteriorated)
- Structural abnormalities in pre-frontal cortex (where personality held)
What were the evaluation points for Swayze’s neural correlates brain study?
👎- Andreason (1982)- criticised neural correlates explanation for schizophrenia- found that extent to which ventricles in 🧠 enlarged by in schizophrenic patients ✖️ significant & … very small difference between neural correlates of schizophrenic patients’ & normal people … neural correlates might ✖️ be a major factor in causing schizophrenia
👍- supporting psychological evidence- states that schizophrenia caused by neural correlates changing in 🧠- occur during pre-natal development in womb & why schizophrenia occurs in early adulthood explained by Weinberger (1987)- pre-frontal cortex (area effected by schizophrenia) develops during adolescence & therefore damage to this part of 🧠 only noticed during adolescence & adulthood (when symptoms of schizophrenia become apparent)
👎- cause & effect ✖️ established- abnormal neural correlates cause schizophrenia or schizophrenia occur 1st (due to other factors) & then cause 🧠 structure/neural correlates to alter?
What are neurotransmitters and what are its roles in the body?
Neurotransmitters- 🧠 chemicals that communicate info throughout 🧠 & body- relay signals between nerve cells called neurons
- Nerve impulse reaches end of a neuron & neurotransmitter released- travels from 1 neuron to the next across synapse
What is dopamine and what is its role in the body?
Dopamine- neurotransmitter released by nerve cells to send signals to other nerve cells
- plays major role in motivational component of reward-motivated 🏃♂
- expectation of rewards ⬆️ dopamine in 🧠
- involved in motor control & in controlling release of various hormones
What are excitatory neurotransmitters?
Excitatory neurotransmitters- trigger nerve impulses in receiving neuron & stimulate 🧠 activity e.g. ⬆️ levels of dopamine ⬆️ drive & motivation … dopamine excitatory neuron
What are inhibitory neurotransmitters?
Inhibitory neurotransmitters- hinder nerve impulses & calm the person, these are called, e.g. serotonin ✖️ stimulate 🧠
What is the endocrine system?
Endocrine system- responsible for producing hormones in body
- Consists of ductless glands that release hormones into body that affect 🏃♂
What are the evaluation points for neurochemistry/neurotransmitters and their affect of behaviour?
👎- criticised by 🧠 approach- states that 🏃♂ caused by thought patterns & 🤔 rather than neurochemistry/chemicals (neurotransmitters) e.g. depression caused by ➖ 🤔 according to 🧠 approach rather than by ⬇️ serotonin
👍- Neurotransmitters- measured objectively & scientifically which is a strength- e.g. dopamine measured by inserting needle into spine & extracting spinal plasma fluid- scientific 🧪 measurements of neurotransmitters-> accurate findings
👎- cause & effect ✖️ established- ⬆️/⬇️ levels of neurotransmitters cause a change in 🏃♂ or does 🏃♂ change-> ⬆️/⬇️ in neurotransmitters
👍- better treatment- if we know lack/excess of particular neurotransmitter-> change in 🏃♂ the we can give people suitable to treatment to fix neurotransmitter imbalances e.g. ⬇️ levels of serotonin-> depression … give depressed ppl SSRI drugs which ⬆️ serotonin
Who studied neurochemistry & schizophrenia further to come up with the dopamine hypothesis?
Davis & Neale
What are the levels of dopamine like in schizophrenic patients?
Schizophrenic patients have ⬆️ levels of neurotransmitter dopamine in 🧠-> ⬆️ firing of neurons
What drugs can be given to schizophrenic patients to reduce dopamine levels? ALSO how are dopamine levels reduced & what are the effects?
When drugs e.g. phenothiazines given to patients’ that block dopamine at synapses in 🧠- symptoms of schizophrenia ⬇️ (hallucinations & delusions)
What drug can increase the levels of dopamine and what are the effects of it in schizophrenic patients?
Drug called L-Dopa ⬆️ dopamine levels in 🧠-> symptoms of schizophrenia
How do the amount of dopamine receptors & dopamine in schizophrenic patients compare to normal people & where is brain activity greatest?
Post mortem studies found that schizophrenic patients’ have ⬆️ amount of dopamine receptors & dopamine in left amygdala of 🧠
What is dopamine metabolism like in schizophrenic patients & how is this monitored?
Dopamine metabolism in schizophrenic patients ALSO abnormal- monitored by PET scans (Positron Emission Tomography)
What are the evaluation points of the dopamine hypothesis & its effect on behaviour?
👎- Cause & effect ✖️ clear- does ⬆️ in dopamine-> schizophrenia OR does schizophrenia develop (due to another cause) -> ⬆️ in dopamine … difficult to identify whether ⬆️ dopamine causes schizophrenia
👍- research support- Davidson found that when schizophrenic patients given drug L-Dopa (⬆️ dopamine)- their schizophrenic symptoms got worse & intensified- … seems that dopamine has key role to play when examining causes symptoms of schizophrenia
👎- reductionist- reduces complicated causes of schizophrenia down to component of dopamine alone- potential other factors/causes of schizophrenia ignored
👍- scientific 🧪 evidence & support- research used evidence from 🧠 scans (PET & fMRI)-> ⬆️ valid & reliable info- 🧪 & objective data helps psychologists look at root cause of schizophrenia
