As we know, there are hundreds of millions of thousands of brain cells of the brain, distributed every brain cell is extremely weak brain waves.People use eeg machine, the weak brainwave accepted, through the instrument amplifier, display electroencephalography (eeg) and eeg, becomes the people see.Eeg waveform with alpha, beta, theta and delta and gamma waves.Among them, the alpha is normal wave, beta is fast wave, the delta wave and theta is slow wave.A normal electroencephalogram (eeg), the basic rhythm should be alpha advantage, can have a small amount of theta.When a person have the central nervous system disease, there is may appear abnormal electroencephalogram (eeg).For example, when the brain disease, tumor, hematoma and cysts can occur in the side of the lesion limitations abnormal brain waves, such as theta and delta waves.Eeg examination for the diagnosis of encephalitis sometimes more accurate than cerebrospinal fluid test.Electroencephalogram (eeg) also can be used for the diagnosis of epilepsy.In addition, craniocerebral trauma (such as concussion, brain contusion, etc.), some cerebrovascular diseases (such as cerebral hemorrhage, subarachnoid hemorrhage, etc.), body disease, affect the brain function (such as hepatic encephalopathy, pulmonary encephalopathy, kidney disease, etc.), is likely to be abnormal electroencephalogram (eeg).

Eeg can diagnose mental illness?It'll have to see what kind of mental illness


Many different kinds of mental illness, clinical manifestations and very complex.Is the cause, generally can be divided into three categories.The first is functional mental illness, such as schizophrenia, affective psychosis, reactive psychosis and so on.Have yet to find mental illness has obvious brain organic disease, therefore, the significance of eeg examination is not big.The second is because of heart, lung, liver, kidney disease, poisoning, somatic diseases such as metabolic disorder caused by mental disorders, eeg examination has a certain reference value.The third kind is the brain have implement qualitative sex pathological change, such as encephalitis, brain tumor and epilepsy caused by cerebral organic psychosis, higher positive rate of this kind of mental eeg examination, reference value is bigger also.Thus, electroencephalogram (eeg) can detect psychosis, should be determined by the nature of mental illness.

Finally, still have to explain, in the diagnosis of a person without mental illness, a prudent and responsible attitude, should not only by the check of electroencephalogram (eeg) as a result, also combining with the history, physical examination, etc., must also be psychological tests when necessary, and these data are combined to jump to conclusions.


Normal waveform of eeg machine


Electroencephalogram (eeg) of the waveform is very irregular, according to its frequency, amplitude and physical characteristics is divided into the following four basic waveform.


1. 8 ~ 13 hz per second, alpha frequency amplitude 20 ~ 100 mu V.Normal quiet, sober eye closure.Opened his eyes, or to accept other stimulation, disappear and presents the fast wave, known as alpha.


2. 14 ~ 30 hz frequency of beta waves per second, the amplitude of 5 ~ 20 mu V.Open your eyes see things, suddenly heard the sound, or thinking can appear when the wave.Beta is generally recognized as the performance of the brain cortex.


3. Theta frequency per 4 ~ 7 hz, amplitude mu 100 ~ 150 V.When sleepiness, lack of O2 or depth of anesthesia.


4. The delta wave frequency per 0.5 ~ 3 hz, amplitude 20 ~ 200 mu V.Adults can appear when sleeping, awake without the wave;In the depth of anesthesia and lack of O2 may also occur.


Eeg rhythm changes along with the different of the cerebral cortex activity state.When the electrical activity of many neurons cerebral cortex to have consistent pace, appears the frequency and higher amplitude of rhythm, called synchronization, such as alpha is synchronized rhythm.When little electrical activity of neuron is consistent, is characterized by high frequency and low amplitude of rhythm, called to synchronization, such as alpha blocking and appear when the beta is to synchronized rhythm.Brain tumor or epilepsy, author, brain wave will happen some characteristic changes, so the eeg examination has a certain value to the diagnosis of these diseases.