It is well known that the brain is an electrochemical organ. Researchers have speculated that a fully functioning brain can generate as much as 10 watts of electrical power. Other more conservative investigators calculate that if all 10 billion interconnected nerve cells discharged at one time that a single electrode placed on the human scalp would record something like five millionths to 50 millionths of a volt. If you had enough scalps hooked up you might be able to light a flashlight bulb.
Brain waves were discovered by German neurologist Hans Berger in the mid-1920s. Though Berger’s path to this discovery began because he wanted to record what he thought was psychic energy in the brain, he eventually narrowed his focus and successfully made the first recording of electrical waves in the brain: an electroencephalogram, or EEG. Since his discovery, EEGs have been used to provide useful information about one’s mental state and functioning, as they can lead to the diagnosis of epilepsy, sleep conditions, Alzheimer’s, and other issues related to brain functioning.
There are five different types of brain waves, ranging from low to high frequency:
· Delta brain waves- are the slowest brain waves. They are generated in deep meditation and dreamless sleep. Healing and regeneration occur when the brain is in this state.Here the brainwaves are of the greatest amplitude and slowest frequency. They typically center around a range of 1.5 to 4 cycles per second. They never go down to zero because that would mean that you were brain dead. But, deep dreamless sleep would take you down to the lowest frequency. Typically, 2 to 3 cycles a second.
· Theta waves- also occur in during relaxation. They are indicative of an inner focus, and dreams and vivid imagery occur in this state.This frequency range is normally between 5 and 8 cycles a second. A person who has taken time off from a task and begins to daydream is often in a theta brainwave state. A person who is driving on a freeway, and discovers that they can’t recall the last five miles, is often in a theta state–induced by the process of freeway driving. The repetitious nature of that form of driving compared to a country road would differentiate a theta state and a beta state in order to perform the driving task safely.
· Alpha waves- occur during quiet, thoughtful times. Alpha waves indicate that the brain is in a resting state.Where beta represented arousal, alpha represents non-arousal. Alpha brainwaves are slower, and higher in amplitude. Their frequency ranges from 9 to 14 cycles per second. A person who has completed a task and sits down to rest is often in an alpha state. A person who takes time out to reflect or meditate is usually in an alpha state. A person who takes a break from a conference and walks in the garden is often in an alpha state.
· Beta waves- are the most common pattern in the normal waking state. They occur when one is alert and focused on problem solving.When the brain is aroused and actively engaged in mental activities, it generates beta waves. These beta waves are of relatively low amplitude, and are the fastest of the four different brainwaves. The frequency of beta waves ranges from 15 to 40 cycles a second. Beta waves are characteristics of a strongly engaged mind. A person in active conversation would be in beta. A debater would be in high beta. A person making a speech, or a teacher, or a talk show host would all be in beta when they are engaged in their work.
· Gamma brain waves- are the fastest and are associated with higher levels of consciousness.
BRAIN WAVES AND SLEEP
The brain is very active during sleep, and each stage of sleep is characterized by the brain waves that accompany it.
· Stage 1: In this stage, alpha waves are replaced by theta waves as one transitions from relaxation to sleep. Sleep is light and easily disturbed.
· Stage 2: During this stage of sleep, brain waves become slower as alpha activity stops completely and theta waves predominate.
· Stages 3 and 4: These stages are very similar in that both are forms of deep sleep. Brain activity slows down as delta waves occur. These are the stages during which sleepwalking and nightmares occur.
· Stage 5 (REM): During the rapid eye movement (REM) stage, the muscles become temporarily paralyzed, and the eyes move quickly. Dreaming also occurs during this stage. The pattern of brain waves is similar to that in stages 1 and 2, although the sleeper is in a deeper state of sleep.
BRAIN WAVES AND MENTAL HEALTH
Brain waves are sinificant to mental health, as abnormalities in brain functioning can influence the development of certain conditions. When certain areas of the brain are over-aroused, an individual may experience anxiety, nightmares or other sleep problems, impulsivity, and aggression. Too little arousal in the brain, on the other hand, has been correlated with depression, chronic pain, and insomnia. If brain rhythms are unstable, an individual may experience obsessive compulsions, develop epilepsy, or have panic attacks.
Neuroscientists have recently discovered a link between an overabundance of gamma waves in the brain and schizophrenia. Gamma waves cause hyperactivity in areas of the brain, and when this hyperactivity is abnormally high, as it often is in those with schizophrenia, delusions and hallucinations can result. Poor sleep, which also results from an excess of hyperactive brain waves, has also been recently shown to be a contributing factor to symptoms of schizophrenia:
Those who have trouble sleeping due to overabundant gamma waves in the brain may experience a “triggering” of schizophrenia symptoms.
Research on brain waves has also shown that certain individuals may be biologically more likely to experience depression. These individuals demonstrate an abundance of alpha wave activity in the left frontal areas of their brain. Another condition that is characterized by an excess of lower frequency brain waves is attention deficit hyperactivity. However, both of these conditions, along with others, have shown improvement when treated with neurofeedback therapy.
Neurofeedback is a therapeutic technique that is used to monitor and change brain wave patterns in an attempt to modify behaviors and improve mental health. In this type of therapy, individuals are taught to alter the flow of brain waves. A therapist uses EEG readings to determine the level of brain waves and assess the predominance of abnormal activity and then rewards the desired brain wave activity to encourage its production. In an individual who has depression, for example, the therapist will use sound and visual effects to reward beta waves in order to help relieve the symptoms of depression.