One of the first scientists to research the impact of meditation was Dr Herbert Benson, a professor at Harvard’s
Medical School. He developed understanding of the ‘relaxation response’ (1975), a
mechanism of the body that can neutralise the ‘fight or flight’ response to stressful
situations. He found that the ‘relaxation response’ could be triggered by meditation and
that when this occurs it causes the following positive physiological changes. It reduces
the body’s heart and breathing rates, blood pressure and muscle tension. At the same time
alpha waves (the normal brainwaves of a person who is awake but relaxed) in the brain
increase. He was able to show that many traditional meditation techniques trigger a
measurable relaxation response and provided evidence of the health benefits of regular
meditation practise such as stress management and reducing high blood pressure.
In 2008, Dr Benson also conducted research into how methods such as visualisation,
meditation and deep breathing switch off disease causing genes at the same time as they
switch on genes that actively protect against illness. During the study the genetic makeup
of long-term practitioners of meditation and similar relaxation methods were compared to
a control group of people who never use these methods. It was found that specific
disease-fighting genes were active in the practitioners that were inactive in the control
group. When the control group began to practise the same methods, after two months of
daily practise, the constitution of their genes began to change. Specific genes that help
fight inflammation kill diseased cells and protect the body from cancer and other forms of
damage began to switch on.
Another study by psychologist David Mc Clelland at Harvard University demonstrated how
positive states of mind can improve our physical health. He showed a group of students a
film of Mother Teresa working among Calcutta’s sick and poor. The students reported
that the film stimulated feelings of compassion. Afterward, he analysed the students’
saliva and found an increase in immunoglobulin-A, an antibody that can help fight
Neuroscientist, Sara Lazar of Harvard University conducted research into the impact of
Mindfulness-Based Stress Reduction (MBSR) training. The brains of those volunteers
who received 8 weeks MBSR training were scanned before and after training. There were
measurable changes in two important brain areas, an increase in the hippocampus, a part
of the brain involved in memory and learning and shrinkage in the amygdala, a portion of
the brain that initiates the body’s response to stress. This decrease in size of the
amyygdala correlated with lowered stress levels in those who received the training and
the more they reduced their stress through meditation, the smaller the amygdala got.
A control group that didn’t receive any MBSR training showed no such brain changes in
scans conducted 8 weeks apart.
MRI scans have been used in many research projects including that of Kathy Sykes, a
professor of Bristol University to see what evidence there is to support the idea that
meditation is beneficial and associated with changes in the brain. MRI scans in long-term
meditators showed that it has an effect on the parts of the brain that involve paying
Scientists have also used EEG machines to understand what happens in the brain when
someone is meditating. The brain waves which have been observed when we are awake
and alert and aware of our surroundings and normally thinking are called Beta waves.
These are high frequency waves and the more stressed you become, the more intense
these beta waves become.
The brain emits Alpha waves when we are in a relaxed state of
wakefulness, commonly known as ‘the meditation state’. Theta waves have been
recorded which indicate a deep meditative and relaxation state. These waves are
predominant at the ages of 2-5 years old when we are at our most creative and
imaginative. When people enter deep meditation, there is an increase in theta waves as
well as alpha waves which give rise to that that feeling of ‘bliss’.
Delta waves are very
low-frequency brain waves and are present when we are asleep and have also been
detected in babies. A study was conducted on a group of Tibetan monks who were long
term meditators. As well as an increase in alpha and theta waves, the monks showed an
increase in gamma wave activity especially when meditating on ‘loving kindness’.
Gamma waves are high frequency brain waves which allow the brain to assimilate
information from different areas to help us make sense of our lives.