Brain wave is spontaneous and rhythmic neuroelectrical activity, and its frequency varies between 1-30 times per second, which can be divided into four bands, namely, δ (1-3Hz), θ (4-7Hz), α (8- 13Hz) and β (/kloc-).
1 and δ wave: the frequency is 1 ~ 3Hz, and the amplitude is 20 ~ 200μ V. When people are in infancy or immature, adults are extremely tired and sleepy or are anesthetized, this area can be recorded in the temporal lobe and parietal lobe.
2.θ wave: the frequency is 4 ~ 7 Hz, and the amplitude is 5 ~ 20 μ V. This fluctuation is extremely significant in frustrated or depressed adults and mental patients. But this wave is the main component of EEG in adolescents (10- 17 years old).
3.α wave: the frequency is 8 ~ 13Hz (average value is 10Hz) and the amplitude is 20 ~ 100μ V ... It is the basic rhythm of normal people's brain waves, and its frequency is quite constant without external stimulation. This rhythm is most obvious when people are awake, quiet and close their eyes. When they open their eyes (stimulated by light) or receive other stimuli, the alpha wave disappears immediately.
4.β wave: The frequency is 14 ~ 30hz, and the amplitude is100 ~150μ V. This wave appears when people are nervous or excited. When people wake up from a nightmare, the original slow-wave rhythm can be immediately replaced by this rhythm.
Extended data:
Brain waves are divided into two parts: the left brain is responsible for numbers, language, logic and analysis; The right brain is responsible for music, art, imagination and creation.
The natural frequency of the left brain wave is β, and the natural frequency of the right brain wave is α.
Adults generally only use the left brain to think, ignoring the right brain, so the brain waves are mainly beta waves.
Children aged 7 ~ 14 are different. They think more with the right brain, so the brain waves are mainly alpha. At this time, children like music, color, art, imagination and creation. However, with their age and education system, the brain's thinking activities will gradually shift to the left brain, and brain waves will accelerate to β.
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