Contemporary research is revealing what ancient yogic science has always known; that restorative practices such as gentle movement, restorative yoga, meditation, and yoga nidra can change your brain. What we know now is that this can occur on structural and electrical levels by influencing brain waves, activity and blood flow in the amygdala, hippocampus, frontal lobe and gray matter. These changes can affect pain perception, task performance, anxiety, emotional behaviour, mood, motivation, and mental focus.
Brain waves
Brain waves are electrical impulses created by groups of neurons firing together. These groups fire at different frequencies or speed and have different, distinct patterns. Different parts of the brain respond to, and function differently according to the combination of brain waves present. As we seek to still the chatter of the mind in yoga practices, we consciously or subconsciously tune into the effects of changes in brain wave balance; coming to know what supports us, and what does not serve us so well.
In active phases of practice and focused activities we are likely to experience beta wave activity, conscious thoughts and an attentive state. We may begin with high beta band waves and progress towards lower band waves as attention moves from highly complex thought, excitement, anxiety and mental chatter towards focused, calm attention. As slower, alpha wave activity increases, we become calm, relaxed, intuitive and present in the now.
What happens to brainwaves in restorative yoga?
Restorative yoga is a practice of supporting the body in different ‘shapes’ or ‘postures’ using abundant props so that our primary response for physical comfort can settle; taking us out of the “fight-flight-freeze” state and into the relaxation response created by parasympathetic nervous system stimulation. This response works through each kosha (layer or sheath) from physical, breath and emotional to mental and energetic rest and relaxation.
As the right and left-brain hemisphere activity comes into greater balance, brain waves shift from beta (awake state – lots of brain activity), to alpha (brain activity slows down – shifting to rest). With greater alpha activity the mood enhancing hormone serotonin is released, enabling easeful access to a calm state.
Depending on the length of time spent in each shape, and baseline beta activity relating to stress or anxiety on entering the practice, it is possible to continue to transition into a deeper alpha and theta state where thoughts slow down even more, and emotions can be processed and/or released. In alpha theta our learning processes and creativity are enhanced and we are more attuned to sound, images and dreams.
In restorative yoga care and attention is taken to achieve supreme comfort in each shape that can then be maintained for 6-12 minutes, depending on the part of the body, breath, energy, or awareness that the posture seeks to make accessible. The predominant brain waves are deep alpha and theta; associated with a relaxed, dreamy brain and body rest state. If / as we access more theta activity the state is closer to light sleep, deep learning, memory consolidation and stronger emotional awareness. Theta state can be the closest thing to being asleep without being asleep – a hypnogogic state.
Diving deeper with yoga nidra
Deep alpha theta waves are associated with REM (rapid eye movement), or the pre-sleep state. This state can be transcended with the prolonged rest and guided meditation that occurs in yoga nidra to access the blissful delta brain wave state. Delta waves are slow and deep, thoughts slow down even more, organs regenerate, the stress hormone cortisol is metabolised, and excreted through enhanced liver and kidney activity (respectively). Whilst delta state occurs in deep sleep it can also be accessed through yoga nidra as we practice detached awareness in deep meditation.
What state am I usually in?
Normal waking consciousness is associated with dominant beta wave activity. Although ‘normal’, continuing to function in this state consumes a huge amount of energy, and is far from efficient in terms of brain maintenance and self-care. High beta frequency activity is especially hard on the system, and is associated with tension, stress, anxiety, insomnia, nightmares, agitation, depression, and chronic pain.
When beta waves always dominate our brain wave activity, alpha wave activity can literally disappear and this has a profoundly negative effect on our sleep quality and the ability to restore, repair, and heal. Without alpha wave activity we bypass restorative sleep – going from a day dominated by high frequency beta waves to the shallow sleep associated with theta waves…right back to beta upon waking up. We miss deep, restful delta wave activity and can feel tired and anxious on waking. This is what often happens in generalised anxiety states, leading to unrelenting fatigue and increased risk of depression.
The benefits of rest
Regardless of the practice you may choose, or favour, rest is everywhere when we learn to attune to its rhythms and an intention to unfocus – to quieten the fluctuations of the mind and the chatter of everyday consciousness – the voice of beta wave activity. Slowing down leads us into awareness, attention and a quieter mind. We can transcend the busy, high frequency waves to access a calmer, quieter voice of alpha waves, and our innate intuition.
