Astanga Hrudaya
वाक्प्रवृत्तिप्रयत्नोर्जाबलवर्णस्मृतिक्रियः। व्यानो हृदि स्थितः कृत्स्नदेहचारी महाजवः॥६॥
its functions are initiation of speech (vak), effort (Prayatna), enthusiasm (Urja), strength (bala) , color, complexion (varna) and memory (smruti). Vyana Vata –Vyana is located in the heart, moves all over the body in great speed,
english translation