Studying the brain Flashcards
(9 cards)
What are all the ways to study the brain?
- fMRI
- Electroencephalogram
- Event-related potentials
- Post-mortem examination
How do fMRI work?
- Measures the blood flow in the brain when a person performs a task
- It works on the idea that the neurons that are the most active (during a task) are the ones that use the most energy
- It creates a dynamic 3D map of the brain highlighting the areas involved in different neural activities
Evaluate fMRI
- One strength is that it is non-invasive meaning it does not require any instruments to be inserted into the brain making it risk-free
- One limitation is that it has poor temporal resolution (the accuracy of the scanner in relation to time). fMRI has a temporal resolution of 1-4 seconds whereas EEG/ERP are 1-10miliseconds
How do EEG’s work?
- They work on the idea that information is processed in the brain as electrical activity in the form of nerve impulses (transmitted across neurons)
- They measure this activity by electrodes attached to the scalp
- Small electrical charges and detected by the electrodes and are graphed overtime to show the level of brain activity.
Tell me about the EEG patterns
4 types of EEG patterns:
- Alpha waves
- Beta waves
- Theta waves
- Delta waves
Each of these patterns have 2 properties that psychologists examine:
- Amplitude (the intensity/size of the activity)
- Frequency (the speed or quantity of activity)
What are the 2 distinctive states that EEG patterns produce and what are they usually associated with?
Synchronised patterns - where a recognised waveform (alpha, beta, theta & delta) can be detected. Associated with sleep
Desynchronised pattern - no pattern detected. Associated with being awake
Evaluate EEG
- They have poor spatial resolution (the smallest measurement a scanner can detect). They only detect activity in superficial regions of the brain and are unable to provide information about deeper regions of the brain such as the hippocampus.
- Can be uncomfortable for the participant meaning the readings could be unrepresentative.
How do event-related potentials work?
- Electrodes are also attached to scalp but the difference is that a stimulus is presented
- The research looks for activity related to the stimulus
- A process called ‘averaging’