Neuro-science that underlies Meditation, for the layman

by Dr Channa Ratnatunga

The human brain has been now shown to continuously adapt to demands of a life-time. This is referred to as Neuroplasticity. It was an evolutionary need for survival which fortunately persists. It is a new finding.At birth, we endowed with a survival kit, to appease hunger, thirst, maintain our body heat and ward-off threats. Sense pleasures are endowed too, so as to propagate the species. These operate through the brain by reflex. The reflex involves the primitive brain i.e. the Reptilian brain (See Fig 1 below).

In time, beings evolved to carry its young in a womb as opposed to laying eggs. Humans, as in all mammals, were perforce, had to live within a herd, as a social animal to ensure the survival of its young, The brain developed (the Neo – Cortex), to control (auto-regulate) these instinctual behaviours , so as to meet the needs of the life among the herd. But once provoked such regulation falls short. Anger, hate, ill-will, jealousy, craving, sexual misconduct are unmasked in the individual without a well-trained regulatory mechanism in their neo-cortex (pre-frontal lobes) (see fig 2) fails to control these instincts of the primitive brain. Such auto-regulation is the basis of sila.

Such mental training is added to by demands of professional life which has followed evolution of modern society from basic life amongst the herd. Those who attitudinally seek excellence in their profession. It is simply an offshoot of this potentiality of the brain called neuro-plasticity. It involves ‘task positive networks’ within the brain which involves many centres within mostly the neo- cortex

Skills development i.e. an expert in any field, be it a top violinist, pianist, surgeon, cricketer or carpenter etc. will develop, with time neuronal circuits (brain cells and circuits of a high complexity) by neuro-plasticity, which by regular practice is done by quicker and more substantive release of substances at neuronal junctions that help transmit the neuronal impulses. These are to reiterate, task positive neuronal networks (circuits), developed by neuro-plasticity.Such activity entails; hand-eye coordination, memory, executive skills such as decision making, planning and many other skills which the brain has, by intense practice gained, to reach its peak performance.

Likewise, an expert meditator, having at first auto-regulated his reptilian brain (the fetters) can meditate, be it Samadhi (focused mind) or Vipassana (open non reactive) can enter the meditative state of mind with ease by regular practice. With time and focused practice, he/she too will enter the meditative state which by then has become a trait, and lasting throughout the day and persists in all activity, be it mental or mentally induced physical. Neuro-plasticity being the background.

Neuro imaging and Electro- encephalographic tracing (i.e. electrical activity of the brain) of Tibetan monks who by virtue of several thousand hours of meditative practice, made such an ability a trait show intense ‘gamma- wave forms’ of electrical activity in their entire brains Such wave forms are induced by intense concentration, with low key activity in their Amygdala (part of the primitive brain).

Buddhist philosophy advocates such intensity of mind training in mindfulness meditation for us to transcend the conditioning our brain-mind is exposed to, that happens during the course of our survival in the life process. This it is alleged, adds to what Karmic energy we have to overcome, that we have carried forth from Sansara, before we could become aware of cosmic consciousness.