Biological Approach Flashcards
(47 cards)
What is the definition of localisation?
The idea that a given function is localised in specific areas of the brain. This essentially means that certain brain structures or brain regions are the genesis of particular behaviours, cognitions and emotions.
What is the hippocampus and what does it do?
It is part of the limbic system (lies in the centre of the brain and is associated with emotion, memory and motivation), known to be impacted in emotional regulation and long-term memory.
What is the amygdala and what does it do?
It is part of the limbic system, associated with the emotion of fear as well as memory.
What is the hypothalamus and what does it do?
It is part of the limbic system,helps to regulate the autonomic nervous system and communicates with the endocrine system.
What are the limitations of the model of localisation?
Lashley claimed that intact areas of the cortex could take over responsibility for specific cognitive functions following brain injury. This therefore casts doubt on theories about the localisation of functions, suggesting that functions are not localised to just one region as other regions can take over specific functions following brain injury.
What is strict localisation?
The idea that there is a clear correspondence between psychological functions and brain areas, and that all functions can be clearly mapped onto the brain.
What is weak localisation?
The idea that one brain area may be responsible for a function, but not exclusively, and other areas may also take over the function.
What are widely distributed functions?
They are functions that cannot be localised anywhere in the brain.
What is neuroplasticity?
The ability for the brain’s physiology to change over time. This is often due to environmental inputs; however, it can be due to innate genetic causes as well:
- occurs at the beginning of life when the immature brain organises itself.
- occurs in cases of brain injury, to compensate for lost functions or to maximise remaining functions.
- occurs throughout adulthood, whenever something new is learned or memorised.
What are neurotransmitters?
A chemical substance of any group released by neurons (nerve cells) to stimulate neighbouring neurons or muscle or gland cells, thus allowing impulses to be passed from one cell to the next throughout the nervous system.
What is acetylcholine?
Causes muscles to contract, activates pain responses and regulates endocrine and REM sleep functions.
What is dopamine?
A chemical released by neurons (nerve cells) to send signals to other nerve cells. The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behaviour.
What techniques are used to study the brain?
Computerised axial tomography (CAT); Magnetic resonance imaging (MRI); Functional magnetic resonance imaging (fMRI); Positron emission tomography (PET); Electroencephalography (EEG).
What is the full name for fMRI?
Functional Magnetic Resonance Imaging.
What are the 3 main fMRI functions?
- detects changes in oxygen levels in blood flowing through the brain.
- when an area of the brain is active, there is increases blood flow to that area, as more oxygen is needed by active, functioning neurons.
- compiler analyses blood-oxygen levels in area, creates image with colour variations.
What are 5 things that fMRI can allow someone to see?
- The brain can be seen three-dimensionally.
- the identification of brain areas that are particularly active during a given task
- the colour variations show level of activity in different areas of the brain when participant is given a task.
- detect brain changes as they occur from moment to moment by taking many pictures rapidly.
- metabolic function.
What are 4 advantages of fMRI?
- can take numerous pictures of brain in rapid succession which provides and image of brain activity averaged over seconds making it easy to see the changes.
- highly detailed
- no exposure of radiation
- colour coding enables for an easy interpretation of brain functioning.
What are 6 disadvantages of fMRI?
- researcher needs to remain aware of task given to participant
- cannot be used with people who have metallic devices
- can be an issue with claustrophobic people (requires being in a narrow tube).
- lying down for a long time
- noisy/ loud
- expensive
What is the full name for MRI?
Magnetic Resonance Imaging.
What are the 3 main functions of MRI?
- harmless magnetic fields and radio waves to vibrate atoms in the brain’s neurons to produce an image of the brain.
- vibrations detected by huge magnet in chamber surrounding the person, then channeled into a computer.
- computer processes vibration and assembles into a coloured image.
What are 5 things that the MRI can allow someone to see?
- produces high-resolution three-dimensional image of brain structure, can also be viewed two-dimensionally.
- coloured images indicate areas of high and low brain activity.
- detect and display extremely small changes in the brain.
- clearly distinguishes between brain cells that are cancerous and non-cancerous.
- anatomical structure.
What are 5 advantages of MRI?
- enabled more precision in study (than techniques before MRI) of structure of live, human brain.
- non-invasive
- harmless
- invaluable for determining damage or abnormalities to specific brain areas or structures.
- does not use X-rays or radioactive substances.
What are 6 disadvantages of MRI?
- cannot be used with people who have metallic devices
- shows only brain structure, or anatomy - not function
- can be an issue for claustrophobic people
- lying down for a long time
- noisy/ loud
- expensive
What are hormones?
They are chemicals released by specific glands in the body to regulate medium-term and long-term changes in the body. They travel with bloody and allow for lesser voluntary control.
They do not influence behaviour; they change the probability that a certain behaviour will occur in response to a certain environmental stimulus.
