Xin 
regulates both Blood circulation and its volume, while Gan 
stores Blood like a reservoir. The two viscera, therefore, coordinate Blood circulation. Xin regulates the activities of the Spirit. Gan regulates dredging and dispersing, which adjust emotional activities to maintain a balance of health. The two viscera, therefore, also coordinate mental and emotional activities.
Deficient Xin -Blood and Gan -Blood often affect each other, leading to a pale complexion, palpitations, insomnia, blurred vision, and so on. The conscious mental activities of a person are controlled by Xin and benefit from the smoothing function of Gan . Xin and Gan often affect each other, as in the flaring-up of Fire of both viscera.