Waves of Samadhi

Samadhi is defined as mental one-pointedness in the suttassamādhi (Siriniwasa, 2016). It is when the mind’s attention is completely absorbed into one object. However, this vastly oversimplifies the depth of meaning behind the word. Samadhi is an altered form of consciousness, where practitioners who achieve such a state feel a sense of unity with all existence. An experience so profound and divine that it is impossible to describe in words fully. Samadhi achieved through dedicated meditation and yoga practice. Let us explore how science can validate or explore this realm of consciousness.

One exciting tool that scientists use to research the mind during meditation is through electroencephalogram (EEG). EEGs detect the electromagnetic waves emanating from neurons through their activation. Specifically, they detect the voltage fluctuations from ionic movement within neurons as action potentials occur (Kora et al., 2021). There are generally five bands of waves detected, and they usually represent different mental activities (Kora et al., 2021):

• Delta waves, 1-4Hz: These are the lowest frequency waves, usually observed during deep sleep.
• Theta waves, 4-8Hz: This is the second-lowest frequency of waves, and it is usually detected once a mental task becomes autonomous to do the repetitive mastery.
• Alpha waves, 8-12Hz: This wave represents moderate levels of brain activity and occurs when an individual is temporarily idle, still, relaxed, yet still alert.
• Beta waves, 12-30Hz: This wave represents another form of alert consciousness but is more associated with mental tasks, academic performance, and heightened states of cognitive awareness.
• Gamma waves, 30-100Hz: This high-frequency wave is thought to be involved in conscious attention. They are essential for establishing normal circuitry.

Generally, we understand that the lower the brain wave frequency, the more relaxed and tranquil the mind. However, that is not to say that the higher frequency bands are unnecessary. Gamma frequencies, for example, are extremely important for healthy cognitive function.

What does all of this have to do with Samadhi and meditation?

Very few papers explore the state of Samadhi itself, which is to be expected, as Master meditators achieve Samadhi, and science is limited by the infrequent study of the mind of such a master. Science may not always know how to ask the right question, even when they do. Despite all of this, there is an excellent example of a study where researchers performed EEG analysis on a Sri Lankan monk who meditated to achieve Samadhi (Hagerty et al., 2013). In this study, the researchers noted that the brain wave frequencies slowly decreased towards the alpha and theta bands as the monk progressed towards Samadhi (Hagerty et al., 2013). The mind became calmer and more tranquil as the monk reached such an enlightened state.

Though this is one of the only studies directly monitoring the brain during Samadhi, many studies monitor the brain waves during meditation. In one study, researchers noted that an increase in gamma waves is a common thread across varying meditative and yogic practices (Braboszcz et al., 2017). Additionally, it has been found that typical individuals only express gamma-band frequencies in brief moments throughout the day. On the other hand, expert mediators experience gamma frequencies constantly throughout the day (Lutz et al., 2004). Though this may seem counter-intuitive because gamma waves are on the opposite side of the spectrum compared to theta waves, recall that gamma waves are incredibly vital to attention and consciousness (Kora et al., 2021).

Additionally, gamma oscillations have been theorised to represent the integration of large groups of neurons (Rodriguez et al., 1999). Perhaps meditation not only calms some areas of the mind but also allows different parts of the brain and body to communicate more effectively, allowing for greater harmony across all systems. Lastly, gamma-band activation is also associated with learning (Miltner et al., 1999). Therefore, it is undoubtedly a state of mind worth fostering.

The mind and body are immensely complex. So too is the world around us. We humans often try to understand the world through rationalisation and knowledge. However, the science of meditation and Samadhi suggest something different. When the mind focuses its attention on sensations and feelings rather than thoughts and logic, it changes the way it activates. Some areas of the mind calm and become tranquil, while the more extensive neural brain network communicates more efficiently. The mind is our window to consciousness and understanding. When it functions more efficiently, our understanding of reality becomes more profound. Perhaps, this high functioning ‘gamma wave oscillating brain’ is how we better reach into understanding Vipassanāsamādhi, whereby we have deep insight into the direct and penetrative realisation of the three fundamental Buddhist truths of existence:

1) Anicca – impermanence
2) Dukkha – suffering
3) Anatta – impersonality or soulless.

Read more about the above in our upcoming article on the Science of Karma.

Listen here for more on the gamma waves in meditating monks:
ABC radio “Science of Fate”