There are four basic groups of brain wave frequencies which are associated with most mental activity.
First Group - beta waves (13-35 hertz or pulses per second) is associated with normal activity. The high end of this range is associated with stress or agitated States which can impair thinking and reasoning skills
Second group - alpha waves (8-12 Hertz) can indicate relaxation. Alpha frequencies are ideal for learning and focused mental functioning
Third group - theta waves (4-7 Hertz) indicates mental imagery, access to memories and internal mental Focus. This state is often associated with young children, behavioural modification and sleep/dream states.
Last group - ultra slow delta waves (0.5-3 Hertz) is found when a person is in deep sleep.
Watching te-lie-vision induces low alpha waves in the brain.
The frequencies from your tv can affect your nervous system.
Hence the term "brainwashing box"