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These states of consciousness can be objectively assessed through a psychological assessment (both through observation and self-reported interview) though we can observe these same states through physical responses as well. The names of the Hz range that correspond to these characteristics are used to describe the corresponding states of consciousness, though I will only mention those that are pertinent to hypnosis.
Different brain structures generate different frequencies and patterns, and during normal consciousness, there is an ideal balance of these different brain wave patterns taking place all at once.
But it makes sense that if the problem-solving centers of the brain that generate a particular waveform are not being utilized heavily, there will be an overall decrease in those patterns. So this description of consciousness based on one wave form describes the predominant and general, overall pattern described. (For example, some very logical, left-brained people will generate beta waves all throughout their sleep cycle when those patterns are nearly absent during sleep for the general population.)
Waking hypnosis can then take place during normal consciousness, even though a person might not be in a completely relaxed state, the general state that allows for the bypassing of critical thought to introduce focused, selective thought. It may also tend to occur when the oscillations of the brain wave patterns vary just between critical thought and a state relaxed alertness at approximately 12 - 15 Hz, at the Beta-Alpha Border. Beta State:
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Hypnotherapy seeks to induce an Alpha state so as to more easily refocus attention (or introduce new information), and it is also an ideal state of mind for reading comprehension. The brain absorbs and stores information uncritically in this state of consciousness. The body will shift into an alpha state in response to certain physiologic factors: eye movement and deep, rhythmic breathing. Note that when a person’s gaze is directed to 30 degrees above midline or when a person breathes deeply from the abdomen, the body cannot resist shifting into an alpha state of consciousness. This is a physiologic response to gazing upward (to see a speaker or to view a projection on a display screen). Theta State:
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Why is any of this important? Our activities determine our states of consciousness, but it is critical to note that conditions in our environment and certain stimuli and activities can enhance our tendency to one state or another. If you are in a situation when you need all of your “Beta” functions, anything that causes a natural, physiologic slowing of these brain wave patterns will make you vulnerable. Florescent lighting slows brain wave patterns as do the radiant light patterns of a television screen. If you know that you are going into a situation where you find yourself at a disadvantage, you might wish to do things to keep your Beta functions active and engaged. You can accomplish this through self awareness and through knowledge of how these states of consciousness can work against you.
Recognizing the characteristics of each state can help bring you back into healthy balance and a state of mind that is most appropriate for your circumstances. For instance, if you are a Christian and you sit down to debate with a person of a very different faith about these matters, you would definitely not want to slip into a state of consciousness that made you prone to accepting ideas without discernment. People with problems like ADD tend to fall into a particular brainwave pattern, so this of interest to them if they wish to improve their attention by avoiding any environmental factors that work against them. In an upcoming post, read more about factors that promote alpha and theta activity, especially when attending a conference.
Single brainwave formation graphics noted above: An EEG (electroencephalograph) 1 second sample. The signal is filtered to present only the brain wave patterns of interest. The signal was acquired in the Oz position processed with scipy and saved with matplolib. Created by Hugo Gamboa Dec 2005
Comparison graphic by Intelegen, Inc.