Bio psych Flashcards
Name the different parts of a nerve?
Dendrites, Nucelus, myelin sheath, nodes of ranvier and axon
What is synaptic transmission?
the process in which a neurone communicates a nerve impulse with another neurone
What is action potential?
A nerve impulse travels along the axon of the neurone towards the synaptic terminals on the presynaptic neurone
What does action potential do?
releases neurotransmitters from the vesicles to cross over the synapse and bind to the receptors on the post synaptic neurone
What happens with neurotransmitters binding to the receptors?
Once enough receptors are stimulated it will depolarise the post synaptic neurone, this increases it charge to pass on the nerve impulse. If enough receptors are not stimulated this will hyper polarise the post synaptic neurone.
What happens to any neurotransmitters that are not bound to the receptors?
taken up the reuptake pump on the presynaptic neurone to be stored in vesicles or destroyed by enzymes
How do drugs affect the nervous system?
Drugs can mimic neurotransmitters so they fit receptor sites, they can also block the re-uptake pumps which causes a build up of neurotransmitters in the synapse.
What drug blocks the re-uptake pump?
Prozac
what drug mimics neurotransmitters?
Chlorpromazine
How do people become addicted to recreational drugs?
The brain has a reward pathway, most drugs hack into the dopamine system and increase the level of dopamine causing euphoria. When the drug wears off the person has less dopamine for their brain to function causing dysphoria
When does addiction happen?
when a drug is n o longer active in the nervous system, this can result in withdrawal symptoms. Withdrawal happens when the brain adapts to the changes imposed by the drug so the brain can’t function normal without it
Explain fMRI scans?
Ppants lie down in a scanner, a strong magnetic field is used, the scanners electromagnet cause proton to point in the same direction. Part of the brain with more hydrogen atoms appear paler.
What are the positives of using fMRI scans?
. Produces high quality images of the brain
. Compare structures of brains
. Scientific
. Non-invasive
Explain how fMRI produce high quality images of the brain?
These images are very precise and are sufficient enough to locate and remove delicate tumours. Therefore allowing safer and easier brain surgery to be performed
Explain how fMRI can compare structures of the brain?
Yurgelon- Todd et al used fMRI to obtain data that there is less activity in the frontal lobes of people with schizophrenia than in normal people. Therefore fMRI can aid our understanding, diagnosis and treatment of abnormal behaviour
Explain how fMRI is scientific?
Uses highly scientific equipment to produce images to be interpreted by specialists, these images are checked by other specialists so they are not analysed in a bias way. Therefore can be objectively analysed to see the impact the brain and any brain damage has on behaviour
Explain how fMRI is non-invasive?
fMRI scans do not require any foreign substances being placed in the participants unlike PET scans which use a radioactive tracer. Therefore a fMRI scan is less harmful than a PET scan.
What are negatives of fMRI scans?
- Expensive
- Ecological validity
Explain how fMRI is expensive?
Requires specialist staff to use the machinery and interpret scans produced. Therefore this can limit the use by researchers as they may not have the necessary resources
Explain how fMRI lacks ecological validity?
Conducted in a highly artificial setting on a lab. So the brain activity produced may not be reflective everyday brain activity. Therefore the brain activity cannot be generalised.
Explain how a PET scan works?
A tracer is injected into the blood which bonds to glucose. The pants will be asked to complete a task and areas of the brain which are most active will absorb glucose
What are positives of PET scans?
- Provides data on both structure and function of the brain
- Practical application, Raine et al
- Scientific
Explain how PET scans provides data on structure and function of the brain?
Can see what area of the brain is most active and are responsible for particular types of behaviours. Therefore have extensive knowledge of the brain and makes surgery safer
Explain practical application of Raine to PET scans?
Raine used PET scans to determine brain activity in murderers. He found differences in rain structures to the control group. This can help by putting in early interventions to prevent people developing int murderers.
Explain how PET scans are scientific?
Highly scientific equipment can be used and easily repeated, these images can be checked by other specialists. Therefore can be objectively analysed to see the impact of the brain and brain damage on behaviour
What are negatives of PET scans?
- Ecological validity
- Invasive
Explain how PET scans lack ecological validity?
Conducted in a highly artificial setting of a lab. Therefore the brain activity shown is not representative of everyday brain activity
Explain how PET scans are invasive?
Ppants are injected with a radioactive tracer, some ppants may be uncomfortable with this. Therefore it is unethical.
Explain how CAT scans work?
X-rays are passed through the head and multiple images are taken of the brain. This information is interpreted by a computer and a detailed image of the structure of the brain is produced
What are the positives of CAT scans?
- Detailed images of the structure in the brain
- Non-invasive
Explain how CAT scans produce detailed images of the structure of the brain?
Images are very precise and allow a clear image of the brain structure. Therefore it allows high quality image being produced allowing surgery to be safer.