Glossary

Brain waves are the rhythmic electrical activity of the brain, and different types of brain waves are associated with different states of consciousness:

• Alpha waves
  A medium-frequency pattern of brain activity that occurs when someone is alert but relaxed, such as during meditation or yoga. Alpha waves are associated with mental readiness and play a role in focus and attention.


• Beta waves
  A fast-paced, low-amplitude rhythm that occurs when someone is awake and focusing on mental or physical tasks, such as solving problems or making decisions. Beta waves are stimulating and help with logical thinking.


• Gamma waves
  A very fast brain wave that occurs when someone is fully engaged in problem-solving or information processing. Gamma waves indicate that the brain is firing at its highest frequency.


• Delta waves
  The slowest brain waves, associated with deep, dreamless sleep. Delta waves can also occur during intense meditation or in cases of severe brain injury.


• Theta waves
  A state between wakefulness and sleep that occurs during meditation, prayer, and spiritual awareness. Theta waves are normal in children up to 13 years old, but abnormal in awake adults.