Brain Waves (EEG) and ECG Waveform
Brain Waves (EEG)
Brain waves are electrical signals produced by the brain and measured using Electroencephalography (EEG).
Alpha Waves
- Frequency: 8 – 13 Hz
- Occurs when a person is awake but relaxed.
- Examples: calm thinking, meditation, relaxed state.
- Moderate frequency brain waves.
Beta Waves
- Frequency: 13 – 30 Hz
- Occurs during active thinking and concentration.
- Examples: studying, problem solving, mental activity.
- High frequency with low amplitude.
Gamma Waves
- Frequency: 30 – 100 Hz
- Associated with high-level brain functions.
- Examples: learning, memory processing, perception.
- Fastest brain waves.
Brain Wave Summary
| Brain Wave | Frequency | Mental State |
|---|---|---|
| Delta | 0.5 – 4 Hz | Deep Sleep |
| Theta | 4 – 8 Hz | Light Sleep / Meditation |
| Alpha | 8 – 13 Hz | Relaxed Awake |
| Beta | 13 – 30 Hz | Active Thinking |
| Gamma | 30 – 100 Hz | High-Level Cognition |
ECG Waveform
The electrical activity of the heart is measured using Electrocardiography (ECG).
P Wave
- Represents atrial depolarization.
- Electrical signal spreads through the atria causing them to contract.
QRS Complex
- Represents ventricular depolarization.
- Electrical signal spreads through ventricles causing contraction.
- Normal duration: 0.06 – 0.10 seconds.
T Wave
- Represents ventricular repolarization.
- The ventricles relax and prepare for the next heartbeat.
ECG Wave Summary
| ECG Wave | Function |
|---|---|
| P Wave | Atrial Contraction |
| QRS Complex | Ventricular Contraction |
| T Wave | Ventricular Relaxation |
Easy Memory Tricks
- Brain Waves (Slow → Fast): Delta → Theta → Alpha → Beta → Gamma
- ECG Order: P → QRS → T