The brain is an electrochemical organ. From scientific data gathered through the years, researchers maintain that a fully functioning brain can generate electrical power up to 10 watts.
Some authorities have a more conservative calculation of a single electrode attached to a human scalp generating power of only 5/1000000 to 50/1000000 of a volt if all interconnected brain cells (pegged at 10 billion) discharged simultaneously.
A good number of scalps would then produce enough power to turn a flashlight on.
This electrical power is very minimal and limited, but only the human brain has the power to unleash it and in ways peculiar to the species. Each and every electrical activity originating in the brain is manifested in the form of brainwaves.
Depending on the level of activity from the most to the least brainwaves are categorized into four. When the brain is on the alert and energetically engaged in mental activities, it generates beta waves. These low amplitude waves are also the fastest among the 4 categories.
The measured frequency of these waves ranges from 15 - 40 cycles per second. An actively thinking mind showcases the characteristics of a Beta wave. A person in animated conversation would also be generating beta waves. A debater doing a rebuttal would surely be in high beta state.
A commanding speaker, or a professor, or a host/commentator would all be emitting beta while carrying out their work.
Next in the order of brainwave category is the alpha frequency. Where beta wasassociated with arousal/alertness, alpha stands for the exact opposite. These brainwaves are relatively slower, and proportionately higher in amplitude, with frequencies ranging from 9 - 14 cycles/second.
A janitor who slumps down on a chair after accomplishing a task is undoubtedly in the alpha state. An executive who takes a break for reflection or meditation is, by all measures, in alpha state. A delegate who goes out of the conference hall and does a leisurely round in the garden should be in no other state but alpha.
Third category is composed of theta brainwaves, typically greater in amplitude and much slower in frequency. This type of wave normally toggles from 5 to 8 cycles per second.
A person who stops everything he is doing and just sits there daydreaming is more often than not in a theta state. A motorist who has been driving on the freeway for a while, and realizes he can not remember the last five miles, is surely in theta states lulled by the non-stop, uneventful freeway driving.
The monotony of driving along straight concrete roads compared to that along a scenic and winding country road induces the theta state of mind.
Those individuals who spend a lot of time on the freeway often get brilliant ideas while they are in that theta state. People who often commune with nature get to such level of mental rest that is slower than the alpha and when in theta, they experience a sudden gush of creativity.
This can be attained even in the shower or tub or even when grooming. Theta state is achieved when a task becomes so mechanical that one can disengage mentally from it. The process of ideation that occurs during the theta state is often spontaneous and takes place without any restriction or inhibition. It is a very tranquil state of mind.
The ultimate of all brainwaves is delta, where amplitude is at its highest and frequency drops to the slowest. They generally revolve around the estimated range of 1.5 - 4 cycles per second. Once they drop to zero, you are already brain dead.
Deep dreamless sleep would take you down to the lowest frequency. Typically, 2 to 3 cycles a second.
When we read for a while to coax sleep, we are likely to be in low beta. Once we put the book down or it slips off our hand, we reach for the light switch and close our eyes, our brainwaves drops from beta, down to alpha, lower to theta and finally, when we give in to sleep, to delta.
Humans are known to dream in 90 minute cycles. When the delta frequencies increase wake up into the theta brainwaves, active dreaming takes over and very often becomes experiential or very real to the person.
Typically there is rapid eye movement at this stage. Also known as REM, is a commonly felt phenomenon.
When an individual wakes from deep sleep and shifts to aware stage in preparation for getting up, his brainwave's frequency increases with the specific stages of brain activity. It switches from delta to theta, then from alpha into until finally into beta when the alarm goes off.
If that individual hits the snooze button his frequency is temporarily frozen to a non-aroused state, occasionally into theta, or totally drops back to sleep in delta. During this awakening cycle it is possible for individuals to stay in the theta state for an extended period of say, five to 15 minutes--which would allow them to have a free flow of ideas about yesterday's events or to contemplate the activities of the forthcoming day.
This time can be an extremely productive and can be a period of very meaningful and creative mental activity.
To summarize, there are four brainwave states that everyone goes through without really consciously experiencing them. These brainwaves range from deep undisturbed slumber up to conditions of high arousal.
Research shows that although one brainwave state may take over at any given time, the remaining three brain states surface at any given time depending on the situation he is in.