The brain on fire
The electroencephalogram (EEG) is the depiction of the electrical activity occurring at the surface of the brain. EEG waveforms are generally classified according to their frequency, amplitude, and shape, as well as the sites on the scalp at which they are recorded Sometimes, whole groups of neurons are active at the same time, and this can be seen as brain waves. Different frequencies are associated with different tasks or mental states.
FREQUENCY BANDS OF THE BRAIN
This raw EEG data is described in terms of frequency bands:
GAMMA (25-140 Hz)
Considered to be the fastest brain activity. It is responsible for cognitive functioning, learning, memory, and information processing.
High beta waves (18–40 Hz): known as “beta three” waves and associated with significant stress, anxiety, paranoia, high energy, and high arousal.
ALPHA (8-12 Hz)
Associated with calmness, relaxation and a state of wakeful rest, may even boost your creativity levels.
THETA (4-8 Hz)
Present when we are daydreaming or fantasizing and are commonly associated with creativity and intuition. It is typically a very positive mental state.
DELTA (less than 4 Hz)
Delta waves are the slowest recorded brain waves in human beings. They are found most often in infants and young children, and are associated with the deepest levels of relaxation and restorative, healing sleep.
WHAT ARE BINAURAL BEATS?
A binaural beat is created by playing a different tone in each ear, and the interference pattern between the slightly differing frequencies creates the illusion of a beat. It’s intended to be heard through headphones.
A simple search on how to create binaural beats and you will find free software and instructions on how to create them.
Binaural beats work to try to entrain the brain waves into a particular-frequency band, delta, theta, alpha, beta or gamma. One way in which binaural beats may influence brain waves is through entrainment. Entrainment here means that the activity of your EEG becomes similar to a certain frequency set by an external stimulus.
Another way binaural beats may influence your brain waves is through phase synchronization. It has been suggested, but not thoroughly tested, that auditory beats increase the synchronization of the phase of brain waves in different brain regions.
WHAT ARE MONAURAL BEATS?
Monaural beats are created by the convergence of two separate frequencies but instead of playing a different tone in each ear like a binaural beat, monaural beats play both tones in both ears. You can listen to monaural beats through speakers, you don’t need to use headphones like in the case of binaural beats.
Signal generators (or tone generators) are electronic devices that create pure tones with no harmonics. Tone generators allow you to make a sound at a specific frequency, they can also be used to create binaural beats. Tone generators can be placed directly on specific parts of the body, or used to simply tune an instrument to a specific frequency.
Tone generators can be played in the background of music to try to entrain the brain into any of the brainwave states: delta, theta, alpha, beta or gamma.
WHITE, PINK AND BROWN NOISE
White noise contains sound across all frequencies. There’s also so-called “pink noise” and “brown noise,” which can sound similar to white noise, but have different underlying acoustical properties.
While white noise is composed of a more or less equal mix of low-, medium-, and high-frequency sounds, pink noise and brown noise emphasize low-frequency tones to a greater degree.
These sounds can have a relaxing effect .
A 2012 study in the Journal of Theoretical Biology found people enjoyed more stable, high-quality sleep when exposed to pink noise, as opposed to silence.
Also, a 2017 study from Northwestern University found “sleep-dependent memory” scores improved among older adults after they slept with pink noise humming in their ears.
Nature is full of pink noise, including:
To the human ear, pink noise sounds “flat” or “even.” Examples of brown noise include:
Tip: It’s important when using any kind of noise that it stays at a soft volume. These noise sounds are believed to be extremely effective for breaking up stuck frequencies such as emotions or post-traumatic stress.