Brain waves are electrical signals generated by the neurons in the brain, which are regularly monitored to measure mental activities. Brain waves and their frequency ranges can be measured using an electroencephalogram or EEG. There are four main types of brain waves, each with distinct characteristics:
An EEG can detect various types of disorders, including epilepsy, dementia, stroke, and traumatic brain injury (TBI). It can also be used to monitor for changes in an individual's mental state over time. The test is usually performed by placing electrodes on the scalp, which detect electrical signals from the brain and transmit them to a computer for analysis.
Brain waves are the patterns of electrical activity resulting from the action of millions of neurons.
An electroencephalogram, or EEG, is a visual representation of brain waves measured by placing electrodes on the head. It is used to study brain function and disorders; the absence of brain waves on an EEG indicates brain death.
An EEG can show four types of brain waves: alpha, beta, theta, and delta waves.
Alpha waves are low-amplitude rhythmic waves with an 8-13 Hz frequency. They appear in healthy adults' EEGs during wakeful rest but diminish during sleep or concentration.
Beta waves have a frequency of 14-30 hertz. They are observed when a person is mentally alert and focuses on specific tasks.
Theta waves have a frequency of 4-7 hertz. They are typically present in children. In adults, they can show up during emotional stress and transiently during sleep.
Delta waves are high-amplitude and low-frequency waves present in sleeping adults and awake infants. In wakeful adults, delta waves may also signal brain damage.
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