What Is an EEG Device?
An EEG (Electroencephalography) device is a biomedical instrument that measures and records the brain's electrical activity. Using electrodes placed on the scalp, EEG devices detect brain waves and are among the most fundamental diagnostic tools in neurology.
The brain is an organ where billions of neurons communicate constantly. The electrical activity generated during this communication can be measured and analyzed at the microvolt (µV) level using an EEG device.
How Does EEG Work?
The operating principle of an EEG device consists of these steps:
- Electrode Placement: Electrodes are placed on the scalp according to the international 10-20 system
- Signal Capture: The brain's electrical activity is detected at the microvolt level
- Amplification: Low-amplitude signals are strengthened by electronic circuits
- Filtering: Noise and artifacts are cleaned through digital signal processing
- Recording & Analysis: Processed signals are displayed and analyzed
Types of Brain Waves
The main brain wave types measured by EEG:
| Wave Type | Frequency Range | Associated State |
|---|---|---|
| Delta | 0.5 - 4 Hz | Deep sleep |
| Theta | 4 - 8 Hz | Light sleep, meditation |
| Alpha | 8 - 13 Hz | Relaxed wakefulness |
| Beta | 13 - 30 Hz | Active thinking, concentration |
| Gamma | 30 - 100 Hz | Intense cognitive processing |
EEG Device Applications
Clinical Use
- Epilepsy Diagnosis: Detection and localization of seizure activity
- Sleep Disorders: Sleep stage analysis and narcolepsy diagnosis
- Coma & Brain Death: Verification of brain activity presence
- Neurological Diseases: Monitoring of Alzheimer's, Parkinson's and other conditions
Research Use
- Brain-Computer Interfaces (BCI): Device control through thought
- Cognitive Neuroscience: Attention, memory and emotion research
- Neurofeedback: Brain wave training for performance enhancement
Portable EEG Technology: BioVector
STARGE's BioVector is a multi-channel biosignal monitoring system that captures EEG signals alongside EMG, ECG and EOG. With Bluetooth Low Energy (BLE) wireless connectivity, patients can be monitored without compromising their freedom of movement.
Learn more about our portable EEG and EMG technology on the BioVector project page.
For a comparative guide to biosignal monitoring types, check out our article on EEG, EMG, ECG, EOG: A Complete Guide.