Just as our physical system operates at peak exertion during intense athletics and at a relaxed pace while sleeping, our brain operates at different levels of intensity— consistently cycling through these different levels throughout the day and night.

The following chart outlines the four main levels of brainwave activity with a description of the mental state they induce.
 

Brainwave Frequency	Brainwave Type	Associated Mental State
13-40 Hz	BETA	ATTENTIVE, CONSCIOUS, NARROW FOCUS, COGNITION You are awake, attentive, highly cognitive and alert.  Your mind is sharp and focused.  It makes connections quickly and easily, as you're primed to do work that requires your full attention.  In the Beta state, neurons fire in great number and in rapid succession, helping you achieve heightened performance—but barring you from flashes of intuition.  When you are creating excessively high beta brain waves, anxiety and panic is the result.    * A low Beta brainwave frequency will make you feel focused and increase mental abilities, cognition and IQ.  Use iMusic | Intelligence Suite to enter this mental state and realize these benefits.   * A mid Beta brainwave frequency will put you in a super focused, physically relaxed, hyper alert, mentally quick state: optimizing attentive abilities.  This specific Beta state is best for tackling intense information and making the initial effort to understand something.
7-13 Hz	ALPHA	VISUALIZATION, RELAXATION, INGENUITY Your brain activity slows from the brisk patterns of Beta into the more mellow waves of Alpha.  In the Alpha state, you are truly relaxed and your awareness expands.  Accelerated learning occurs.  A creative energy begins to surface.  New ideas and solutions to problems flash like lightning into your mind.  Fears vanish.  A liberating sense of peace and well being is experienced.   When Alpha brain waves become more dominant, logical left-brain activity—which normally acts as a filter or censor to the subconscious—drops its guard.  This allows the more intuitive, emotional and creative depths of the mind that exist just below the threshold of consciousness to become increasingly influential.
4-7 Hz	THETA	INTUITION, DEEP THOUGHT As your brain slows, you fall into a subtle and mysterious theta state of deeper relaxation, where your mind slows almost to the point of sleep.  Theta is the brain state where the unexplainable occurs in the wake of your own neurological activity.  Theta brings forward flickers of dreamlike imagery, heightened receptivity, early memories and surges of inspiration.  Theta can bring you deep states of meditation, where you experience a sensation of suspension or floating.     As Theta is an expansive state, you may feel your mind expand beyond the boundaries of your body and enter the energy fields that circulate around your physical self.
0-4 Hz	DELTA	DETACHED AWARENESS, SLEEPING The slowest of all brain wave frequencies, Delta brain waves are long, deep and undulating, most commonly associated with deep dreamless sleep.   Your deep Delta state of brain wave activity is one of harmonious relaxation, where both sides of the brain work in synchronization.  The Delta state promotes accelerated physical healing.
* The human brain typically operates in all of the above brain wave frequencies however there always exists a dominant brain wave frequency.  It is this dominant and abundant brain wave frequency that determines our state of mind.