Scientists use a special cap to measure brain waves during meditation. (Credit: Image courtesy of NTNU)

According to latest meditation research, electrical brain waves suggest that mental activity during meditation is wakeful and relaxed.

Professor Jim Lagopoulos of Sydney University, Australia, the lead researcher of the joint study between his university and researchers from the Norwegian University of Science and Technology (NTNU) says, Given the popularity and effectiveness of meditation as a means of alleviating stress and maintaining good health, there is pressing need for rigorous investigation of how it affects brain function.

The study monitored the frequency and location of electrical brain waves through the use of EEG (electroencephalography), by placing the EEG electrodes at specific locations on the scalp using a custom-made hat.

The participants were experienced Acern Meditation practitioners, a nondirective method developed in Norway. They were asked to rest, eyes closed for twenty minutes, and to meditate another 20 minutes in random order. Good indication of the brain activity was provided through the abundance and location of slow to fast electrical brain waves (delta, theta, alpha and beta).

Theta waves were most abundant in the frontal and middle parts of the brain, during meditation. According to Lagopoulos, these type of waves originate from a relaxed attention that monitors our inner experiences and that here lies a significant difference between meditation and relaxing without any specific technique.

Previous studies have shown that theta waves indicate deep relaxation and occur more frequently in highly experienced meditation practitioners. The source is probably frontal parts of the brain, which are associated with monitoring of other mental processes. When we measure mental calm, these regions signal to lower parts of the brain, inducing physical relaxation response that occurs during meditation.

Alpha waves were more abundant in the posterior parts of the brain during meditation than during simple relaxation and they are characteristic of a wakeful rest.

Professor Oyvind Ellingsen from NTNU comments, This wave type has been used as a universal sign of relaxation during meditation and other types of rest.

The amount of alpha waves increases when the brain relaxes from intentional, goal-oriented tasks. This is a sign of deep relaxation - but it does not mean that the mind is void.

The normal resting state of the brain is a silent current of thoughts, images and memories that is not induced by sensory input or intentional reasoning, but emerges spontaneously, from within, suggests Malia F. Mason and co-workers at Dartmouth College NH through neuroimaging studies.

As an experienced practitioner, Ellingsen adds, Spontaneous wandering of the mind is something you can become more aware of and familiar with when you meditate. This default activity of the brain is often underestimated. It probably represents a kind of mental processing that connects various experiences and emotional residues, puts them into perspective and lays them to rest.

Delta waves occur during sleep and there was little delta during relaxing and meditative tasks, confirming that nondirective meditation is different from sleep. Beta waves occur when the brain is working on goal-oriented tasks like planning a date or reflective actively over a specific issue.

During meditation and resting, EEG showed few beta waves. These findings indicate that you step away from problem-solving both when relaxing and during meditation, says Ellingsen.

Better relaxation and stress management is achieved by meditation techniques where you refrain from trying to control the content of the mind, according to several studies.

These methods are often described as nondirective, because practitioners do not actively pursue a particular experience or state of mind. They cultivate the ability to tolerate the spontaneous wandering of the mind without getting too much involved. Instead of concentrating on getting away from stressful thoughts and emotions, you simply let them pass in an effortless way.

More significant changes in the electrical brain wave activity related to wakeful and relaxed attention are achieved through nondirective meditation, than just resting without any specific mental technique.