2.2 - Biopsycholgy (set D - Studying The Brain) Flashcards
Define spatial resolution?
How accurate we can be about identifying the exact location of a brain structure or activity
Define temporal resolution?
Level of accuracy in identifying the exact location of a brain activity when it took place
Give 4 ways of studying the brain?
- FMRI - functional magnetic resonance imaging
- EEGs - electroencephalogram
- ERPs - event related potential
- post mortem dissection
often approaches are combined and results compared to allow for more accurate research and utilisation of pro’s of all methods
Explain the method of FMRI for studying the brain?
- uses magnets to detect blood flow and changes (of oxygenated blood) in the brain
- have the patient complete tasks and detects where higher blood flow is = area is more active compared to lower activation areas with low blood supply
Give 2 advantages of using FRMI to study the brain?
- creates a very detailed image and precisely identity’s active brain regions - good spatial resolution within 1mm (advantage)
- Safer and less invasive compared to options like PET scans which use radiation (advantage)
Give 3 disadvantages of using FRMI to study the brain?
- Delay between when neurones fire and when blood reaches neurones - image taken every few seconds, not live - poor temporal resolution
- Expensive to build and operate - implications to the economy
- participant must remain still for a clear image - reduces use in any experiment that requires movement (may not be a good option for children, ADHD or claustrophobia which can make it hard to stay still)
Explain the method of EEGs for studying the brain?
- collection of between 22 and 34 electrodes attached to a cap and fitted to the scalp with conducive gel
- each electrode picks up activity of an area which is displayed as a series of lines showing distinct patterns called brain waves (amplitude show brain wave intensity frequency and speed of activation)
Give 3 advantages of using EEGs to study the brain?
- historically important in understanding brain activity in areas such as sleep and medical diagnosis
- significantly cheaper than other techniques and is portable - allowing use when looking at movement
- very high temporal validity - measures brain activation practically live within a resolution of mili seconds
Give 2 disadvantages of using EEGs to study the brain?
- Poor spatial resolution - each electrode is picking up a large area of the brain - so not precise
- only from cortex not deep within the brain
Explain the method of ERPs for studying the brain?
- uses same equipment as the EEG (electrodes attached to scalp)
- looks at responses to a particular stimulus and the brain activity is recorded each time - creating a smooth curve of activation by combing data in a process called statistical averaging (removes background electrical noise unrelated to the stimulus)
- waveforms peal and dips show exactly when cognate processes in the brain happen after the stimulus is presented, gather average of activity
Give 2 advantages of using ERPs to study the brain?
- can isolate and study individual cognitive processes taking place in the brain - EEGs record general patterns of brain activity
- good temporal validity but poor spatial resolution (advantage + disadvantage)
Explain the method of post mortem direction for studying the brain?
brains are precisely cut after treatment (treatment done to give a firmer texture) - unusual brains (such as those associated with trauma or mental illness) are compared with a typical (healthy) brain
example is case study of TAN - who it was discovered had damage to his brocas which explained the lack of language production
Give 2 advantages of using post mortem dissection to study the brain?
- only option before advancements in technology for scanning ext - improved knowledge and understanding of the Brian
can study the brain at a high spatial resolution (study brain at a microscopic level down to neuronal level - looking at cells)
Give a disadvantage of using post mortem dissection to study the brain?
- not conducted on a living brain - unusual behaviour in life and damage found in dissection is correlational (possible link - can not say one thing has caused the other)
- but can lead to hypothesis and generation of theories which can then be investigated with other experimental research using scanning technique
Define biological rhythms?
A change in the body processes or behaviour in response to cyclical changes within the environment or internal processes within the body - help us to function
3 biological rhythms