Meditation has numerous benefits, as discussed in my previous article: “Can Meditation Improve Performance?”. In that article, I analysed empirical evidence specifically relating to performance improvements. As you probably know, I am all about improving performance at work, home and life in general through holistic health. Therefore, I was keen to find out specifically how meditation improved performance at work and in life in general. That was the subject of part one which you can find here. That article also included research on how meditation can affect the brain, since the assumption was that work required cognitive skills. Below are the findings from the last article that are relevant to this one.
- Increased cognition
- Increased attention/concentration
- Increased open-mindedness
- Less error prone
- Increased brain size
- Increased brain tissue density
- Slows brain ageing
However, there was so much information, that I decided to create a separate article to look at the additional empirical evidence of how meditation affects the brain.
Let’s start with a study that I found particularly interesting. It was an episode on the ABC’s Catalyst program. The objective of the episode was to see how meditation affects the brain. The producers specifically wanted to see if meditation made you smarter, healthier and happier.
ABC’s Catalyst program – how meditation affects the brain
The Australian ABC Catalyst program aired an episode on June 2016. Presenter, Dr Graham Phillips undertook an eight-week meditation program to learn to meditate. He performed several rigorous cognitive tests and scans at Murdoch University. EEG (electroencephalogram) and MRI scans were conducted both before and after the eight-week program to measure the brain’s electrical activity. The objective was to find out whether meditation can in effect the brain’s performance and physical structure.
The results were notable. Dr Phillips’ brain had grown in many areas. Most notably, a 22.8% increase in a part of his hippocampus, known as the dentate gyrus. The dentate gyrus plays a critical role in learning, memory and pattern separation. It is also one of two areas in the brain where neurogenesis takes place (the formation of new brain cells.
After the eight week program, Dr Phillips also performed better in three out of five of the cognition tests and used less brainpower to do so.
I’m sure you’ll agree, the results were remarkable. You can watch the full episode here, along with a transcript of the program.
Now let’s take a look at brain waves and how they alter during meditation
Overall brain activity does not fluctuate greatly. Normal fluctuations are +- 5%. However, when we meditate brain wave fluctuations can be seen. In addition, when we meditate we can move from higher frequency brain waves to lower frequency. Let’s get an understanding of the different brain waves and what they do.
How Meditation Affects Brain Waves
Firstly let’s understand a little bit about brain waves. Below are the brain waves along with the frequency that they oscillate at:
- Gamma wave – (32 – 100 Hz)
- Beta wave – (16 – 31 Hz)
- Alpha wave – (8 – 15 Hz)
- Theta wave – (4 – 7 Hz)
- Delta wave – (0.1 – 4 Hz)
These waves oscillate at a frequency of 25 to 80 hertz (cycles per second) and occur when you are learning, concentrating, processing information and remembering. Gamma waves are believed to be produced in a sustained meditation state. In the Monk study below, the monks’ gamma waves were 700 times more than normal people.
Beta waves measure between 12 and 35 Hz and occur when you are alert and wide awake
Alpha brain wave frequency ranges from 9 to 14 cycles per second and occurs when you are relaxing. It is thought to be the “the bridge” between the subconscious and conscious mind.
These waves have greater amplitude and slower frequency. This frequency range is normally between 4 and 8 cycles a second. It typically occurs when tasks become so automatic with little conscious thought. Sometimes referred to as daydreaming.
These brain waves a frequency of oscillation between 0.5 and 4 hertz per second. These waves are the greatest amplitude and slowest frequency. The lower the frequency, the deeper the sleep. They are usually associated with NREM (non-rapid eye movement sleep) and normally does not involve dreaming.
Studies of How Meditation Affects the Brain Waves
A review of 56 papers totalling 1715 subjects: 1358 healthy individuals and 357 individuals with psychiatric diagnoses, concluded that mindfulness is associated with increased alpha and theta power
A Psychological bulletin found that EEG measures indicated an overall slowing of brain waves after meditation, with theta and alpha brain wave activation related to proficiency of practice.
A study of Buddist Monks by the University of Wisconsin included 10 long-term Buddhist Monks and 8 college students. Researchers found that during meditation not only did the monks produce extremely high beta and gamma waves, they also, had long-range gamma synchrony. Indicating that the waves from disparate brain regions appeared synchronised for extended durations. In contrast, the students did not demonstrate high gamma waves, nor synchrony. This study was surprising since meditation is normally associated with the slower alpha and theta brainwaves. The monks demonstrated high beta and gamma waves as well as gamma synchrony. Beta and gamma waves are nomally associated with awake, alert states
A recent study found that meditation causes brain entropy, which means intense complexity and irregular variability in brain activity from one moment to another. Brain entropy has been associated with higher intelligence according to a study conducted by New York University.
Participants were 7 Himalaya Yoga meditators, 20 Vipassana meditators, 27 Isha Yoga meditators, and 30 individuals with no meditation experience. The highest brain entropy was recorded by the Vipassana meditators, specifically in alpha and gamma brainwaves. All meditators showed an increase in gamma coherence and gamma-band metastability. Which means, the connection of several parts of the brain to enable the brain to make sense out of seemingly random environmental cues.
Default Mode Network
The default mode network is when certain areas of the brain are active (medial prefrontal and posterior cingulate cortices) and result in you mind-wandering, thinking about yourself, or others in a way that is can be worrisome. This is maybe when you may focus on insecurities or issues in the past or future and can correlate to un-happiness. Washington University found that meditation reduces brain activity in the default mode network.
Researchers looked at brain activity of experienced meditators and non-meditators. Not only did they find that brain activity was lower in the default mode network, they also found increased connectivity and coupling in regions that performed self-monitoring and cognitive control. Which indicates the opposite of the default mode network. This was found both before and during meditation for the experienced meditation group.
The research from both my previous article and this article, clearly indicate that meditation changes both brain structure and brain waves which increases cognition and concentration and reduces stress. The next and final article in the series will look at tips and hacks to meditate.