Outline and evaluate event-related potentials (ERP) as a way of studying the brain. Flashcards
outline
ERPs detect very small electrical changes in the brain triggered by a specific event or stimuli. They record thousands of simultaneous outgoing neural processes, but the brains response to a specific stimuli or event is not visible.
To establish the specific electrical response (the ERP), ‘averaging’ is used whereby the stimulus is repeatedly presented and a computer displays all the images of brain activity for each presentation, on top one another.
The ERP is consistent and always presented, and other general brain activity is inconsistent and the computer filters it out.
For example, participants could be shown a stimulus (e.g., pictures of faces) then the data is analysed for a specific electrical response to the stimulus.
strength
A strength of using ERPs is that they have excellent temporal resolution, which refers to its ability to precisely measure brain activity as it occurs. For example, ERPs can match a stimulus to a response because they occur close together in time.
strength 2
Furthermore, ERPs directly measure neural activity, not just blood flow to an area which means researchers have been able to identify many different types of ERP and describe their precise role in cognitive functioning.
For example, the P100 wave is thought to be involved in the maintenance of working memory.
limit 1
A limitation of using ERPs is that they have poor spatial resolution, which refers to its ability to accurately localise function.
This is because ERPs don’t exactly identify where the activity is occurring, and often it is difficult to eliminate general brain activity.
limit 2
In addition, there is a lack of standardisation in ERP methodology as different research studies use different procedures to identify the ERP.
This means that it can be challenging to make valid comparisons, and to confirm findings.
