What does EEG look like for you?
What are brain waves?
Simply put, brain waves are electrical impulses in the brain. When people think, feel, or act, neurons in the brain “fire” or send an electrical signal to neighboring neurons. Usually though, these individual electrical impulses are not what is referred to by the term brain wave. Rather, brain “waves” are neural oscillations: rhythmic or repetitive patterns of neural activity. These neural oscillations are the result of synchronization among neurons.
What is EEG?
EEG (electroencephalography), is a method of detecting and measuring electrical impulses in the brain using electrodes that are placed on the scalp. These electrodes are small, metal disks that are strategically arranged on a cap and attached by wires to a computer, which displays the electrical waves on a graph in real time. The electrodes detect small electrical signals and measure voltage changes resulting from the movement of ions between neurons, which are nerve cells found in the brain. These EEG signals, which can be recorded during rest, in response to external stimuli, or during mentally stimulating activities, can be analyzed to study cognitive processes and behavior. EEG can be used to monitor abnormal brain activity, study brain activity during sleep or coma, or assess brain damage from injury. The results of an EEG are recorded as waves, which display differing frequencies depending on alertness, arousal, etc.
Why is the net wet?
At the B-RAD lab, the EEG nets will be wet with a saline solution prior to being fitted to the participant’s head. This type of EEG is referred to as wet-EEG. Wetting the net with an electrolytic solution improves the conductivity between the sensors in the EEG cap and the participant’s scalp, allowing for better quality EEG signals to be recorded. It may also be necessary to re-wet some of the electrodes using pipettes during the participant’s visit since they may become dry and less conducive.