Gamma

Gamma (30-44 Hz) Power

Gamma Rule

We reward front left Gamma up in order to facilitate positive emotion generation (Tarrant & Cope 2018). Gamma is an activating frequency, and increases in this frequency band correlate with increased cortical activity. With this rule, we want to raise left cortical activity, which is associated with positive emotions. This helps the Open Heart meditator to better experience positive feelings in the body while attending to Loving Kindness phrases.

Gamma Weights

Levels 1, 2 and 3 meditators are assigned a rule weight of +1. Gamma asymmetry is assigned half the rule weight of the Alpha asymmetry rule because frontal Alpha asymmetry is more established in the literature.

Gamma (25-42 Hz) Power

Gamma Rule

We reward whole-brain Gamma up to increase intensity of feelings (Lutz et al. 2004). During a non-referential compassion meditation practiced by expert monks, researchers found that large amounts of synchronized Gamma band activity (25x controls) happens throughout the cortex and is associated with peak levels of concentration and compassion. By rewarding Gamma across all sites, we strengthen positive emotional engagement and the generation of love and compassion.

Gamma Weights

Level 3 meditators are assigned a rule weight of +1, while Level 4 meditators are assigned a rule weight of +4. This is an advanced brain wave pattern and so is not seen in Level 1 and 2 meditators practicing with Loving Kindness phrases. This rule was derived from a famous study with highly advanced Tibetan monks practicing non-referential compassion meditation (Lutz et al. 2004). Non-referential compassion, also called universal compassion, is an objectless meditation where compassionate feelings pervade the experiencer’s mind as a way of being. Level 4 reflects this advanced practice rather than the repetition of Loving Kindness phrases.

Gamma (25-42 Hz) Synchrony

Gamma Synchrony Rule

We reward Gamma synchrony up to promote a strongly unified brain state (Lutz et al. 2004). Neurons become more synchronized during non-referential compassion meditation, indicating a more globally-integrated brain that is capable of deep feelings of love and compassion. We reward Gamma synchrony in the front and back of the brain to facilitate deep positive feelings.

Gamma Synchrony Weights

Level 3 meditators are given a rule weight of +1, while level 4 meditators are given a rule weight of +2. The rule weight is doubled in Advanced-Expert meditators because this brain wave pattern was only seen in highly advanced Tibetan monks.

Gamma (25-42)/Theta-Alpha (4-13) Power Ratio

Gamma/Theta-Alpha Rule

We reward whole-brain relative Gamma, i.e., the ratio Gamma/Theta-Alpha, which was seen in expert monks to be double the baseline of controls. This metric, while not fully understood by neuroscience, is significantly correlated with the amount of training in Loving Kindness.

Gamma/Theta-Alpha Weights 

Level 4 meditators practicing non-referential compassion are given a rule weight of +2 for this rule. Only Level 4 meditators are included because this is an expert brainwave pattern seen in Lutz et al. 2004.