As early as the 1930s, neuroscientists had rendered the ability to detect brain activity based on the active and dormant flow of neurons. Some of these neurons can be accurately measured as they activate in a flurry, in large groups. The large groups of active neurons are known as a neural ensemble. Neural ensembles are mostly associated with the significant functions of the brain. The brain must even compute the proper neural activity to properly fall asleep and stay asleep.
The levels of activity of these neural ensembles are recorded on an Electroencephalography (EEG) machine, which is used to monitor electrical brain waves. It does so when negatively charged electrodes are placed along the scalp, while the positively charged ionic current of the active neurons in the brain cause a magnetic disruption in the frequency of the electrodes, displaying a dynamic amplitude of neural activity.
The measurement of frequency of neurons is measured in 5 main groups, known as:
- Delta (0-4 Hz)
- Theta (4-8 Hz)
- Alpha (8-12 Hz)
- Beta (12-40 Hz)
- Gamma (40-100 Hz)
Researchers measure these patterns of neural activity to better understand different states of mind. Each of these patterns is linked with a different state of mind. Such disruptions can lead to difficulties with focus, rest, awareness, etc.. Deep meditation is one of the most popular ways people explore these different states of mind. By rendering these frequencies monaurally, or within a rather equal range of both tones, the audio cortex re-focuses on the new frequency produced by the combination of both. For the same reason that songs get stuck in a persons head, the audio cortex will hold the frequency in memory for as long as it decides to, until the next meditation.
Delta (0-4 Hz)
Delta waves, being the slowest brain function, are often associated with unconscious bodily functions such as the heartbeat and digestion, and the body's restorative abilities during relaxation.
Too much delta activity can lead to difficulties with thinking, focusing, and learning and retaining information.
Very slow patterns in this range are associated with deep rest and renewal.
Theta (4-8 Hz)
Theta waves can be a very helpful and powerful brainwave when at an optimal frequency. Theta waves are often involved with intuition and creativity, as well as camaraderie, communion, and connection.
Theta patterns are linked with a dreamy, deeply relaxed and suggestible state.
Patterns in this range are linked with a dreamy, intuitive state.
Alpha (8-12 Hz)
Alpha waves are greatly involved in our conscious ability to accept or allow our subconscious mind to flow freely. On occasion, the Beta waves may overtake the alpha waves, known as "alpha blocking" in which the conscious overtakes the subconscious as a survival mechanism, while an excess of alpha waves can cause deep relaxation when necessary.
Too much alpha activity can lead one to be too relaxed, lacking in focus, and fantasizing frequently.
Patterns in this range are often linked with a restless, unsettled mind.
Beta (12-40 Hz)
Beta waves are mostly associated with our conscious daily cognitive processes in the waking state. This includes our ability to stay task-oriented, to focus, and to solve problems. Much of our necessary logic is best refined when the beta waves are at an optimal frequency.
Fast, busy brainwave patterns are often linked with feeling wound up and over-stimulated.
Slower patterns in this range are often linked with a dreamy, unfocused state.
Gamma (40-100 Hz)
Gamma waves are mostly associated with our brain's ability to intake and organize information. Much of our memory and long-term learning abilities are measured in gamma waves. The Gamma wave has been known to help us connect with our perceivable senses.
Very fast patterns in this range are often linked with feeling over-stimulated.
Patterns in this range are often linked with a foggy, unfocused state.