AO1 - EEG

• Electrodes are places on the scalp using a skull cap
• They detect small electrical changes resulting from activity of brain cells
• The electrical signals are graphed over a period of time to see a person's general brain activity - low spatial resolution
• EEGs are used to detect sleep patterns and states such as sleep or arousal
• It is used as a diagnostic tool to help diagnose conditions such as brain tumours or epilepsy
• High temporal resolution