Studying the Brain

What are fMRI Scans?

Functional magnetic resonance imaging (fMRI) scans are 3D scans providing structural and functional information

How does fMRI show changes in brain activity?

1. More oxygenated blood flows to active areas of the brain (to supply the neurons with oxygen and glucose)

2. Molecules in oxygenated blood respond differently to a magnetic field than those in deoxygenated blood

3. So the more active of the brain can be identified on an fMRI scan

Uses of fMRI

Used to research brain function and structure, diagnose medical problems, study abnormal brain activity, and show brain areas activated during specific tasks.

What do EEGs do?

It shows the overall electrical activity of the brain. It picks up the signal of many neurons firing together- not individual neurons

How does an EEG work?

1. Multiple electrodes are placed on the scalp and the electrical activity in the brain is recorded for a period of time

2. This produces a pattern of waves. These patterns represent different levels of arousal or consciousness. for example, the different stages of sleep each have their own typical wave patterns

Uses of EEGs

Common in sleep studies, studying conditions like depression and schizophrenia, and identifying abnormal patterns for diagnostic purposes.

How would you compare an EEG and an ERP to an fMRI?

• Cheaper

• Non-Invasive

What are the positives of EEGs and ERPs?

Good temporal resolution

What are the negatives of EEGs and ERPs?

Poor spatial resolution

ERPs

Event-related potentials show brain's electrical activity in response to stimuli, allowing researchers to analyse changes in wave patterns.

Uses of ERPs

Used in memory research, identifying differences in ERPs of individuals with psychiatric disorders, and studying information processing in the brain.

Post-mortem Examinations

Involve dissecting the brain post-death to examine internal brain structure, providing insights into medical conditions and localising brain functions.

Uses of Post-mortem Examinations

Show structural abnormalities related to medical conditions, provide evidence for brain function localisation, but require the individual to have passed away for examination.

What is a disadvantage of post-mortem examinations?

The person has to be dead for one to be perform one, so they will not benefit from the findings