The left side channel begins at the Mooladhara Chakra (subtle body chart, 1) and crosses at the Agnya Chakra (subtle body chart, 6) into the superego in the right side of the brain. It expresses the passive mood and the power of desire. Desire is our prime mover, the power by which we exist and the first cause of our creating or seeking. Emotion is born out of desire which is not yet materialised. Therefore, the left is our emotional side.
Weakness in the left side leaves us prone to emotional extremism, where we are thrown between elation and depression. There is very little sense of self-discipline and we become slaves to habits inculcated in us through conditioning. We become very lethargic, retreating into passivity and self-obsession. Eventually the pressure on the brain grows too much to bear and there is a breakdown, culminating in lunacy, epilepsy, senile decay etc.
To correct a weak left side we have to first balance it with the right side. This means activity which develops the ego and pushes the over developed superego back to the central area of the head. So we put more attention outside, on work and action. Discarding all ideas of self-destruction and self-pity, we materialise the emotional side which is attuned to our sustenance. By using the neglected right side, we bring the left into balance with the rest of the being.
The real and greatest quality of the left side is to give us joy which is beyond the duality of happiness and sorrow. The Spirit is always in joy. That joy is expressed in its purity when Kundalini enlightens the attention with the spirit. Actually the joy which is latent in creation starts manifesting through our left side. Then you find joy radiating from any source of divine vibrations.
Your priorities change automatically. Old habits and addictions are over and done with, given up without difficulty. A sense of security is established and all guilt and imaginary fears disappear. Everything created by nature gives a new meaning and one starts enjoying the genuine significance of every ripple they emit.