In the Kosha model, the emotional body is called the prana or life-force body. This is where prana is fully embodied. However, we shouldn’t take this to mean it’s the sole realm of prana.
Like the chakras, prana operates from the celestial or causal body right up through the emotional body.
The fine vibrations or pranava begin the arising of life force or prana, driven by kriya shakti, the power of action. That arises through the subtle quality of liveliness in consciousness, steered by the devata of nature.
The intellect is an expression of gyan shakti, the power of intelligence. This arises through the inherent intelligence of Divinity. However, like Shiva, the intellect is silent without prana. Prana gives the intellect direction and leads the senses out into the field of experiences.
Our quality of intellect is based on the quality of prana. And that, by the dominant quality of the body-mind: tamas, rajas, or sattva. I described the territory of prana above. It’s influenced by food, but also by our thoughts and emotions, where we direct our attention, and the collective we all live in.
When we turn our attention within using spiritual practices, we shift the balance and clear the layers, upgrading the guna and the prana and everything that follows.
As I noted on Knowledge and Ignorance, this process also clears pragyaparadh or the mistake of the intellect. We come to recognize our true nature and the nature of the world.
This is not a small thing. As I’ve described, intellect gives structure (geometry) to the forms that follow. I recently watched a recording of Maharishi Mahesh Yogi where he commented that all manifestations are nothing but bodies [geometry] of the intellect. Expressions are a shell covering that.
If the intellect is mistaken, all forms that arise from that will be without foundation. They’ll support separation and division rather than our unity.
Yet when we correct the error of the intellect and cleanse the prana, it all comes back into balance and perspective. When life force moves smoothly and fully, we experience life accordingly.