For a moment imagine the human body as a musical instrument, especially one of the Indian instruments like the Sitar or Sarangi, which have playing strings that are struck or bowed, and also have 40-odd strings which are never played but are sympathetic strings. When the playing strings are struck, they set up vibratory frequencies that begin to sound the finely tuned but un-struck sympathetic strings. These strings pick up the frequency and vibratory rates of the struck notes and begin to sound and create incredible overtones without being physically touched. It is this design that gives these instruments their unique and meditative sound.
The human organism has a similar design. In Yogic terms, we have the central pranic energy channel (shushmana) corresponding to the spinal column. To either side of it are the ida and pingala, the energies of the sun and moon. Think of these as the playing strings. These energy channels then connect with 72,000 nadis (energy channels) loosely corresponding to the nervous system, that extend throughout the body. Think of these as the sympathetic strings. Whatever we vibrate in shushmana begins to set up a sympathetic vibration in ida and pingala and throughout the nadis that transfer that vibration to all the cells of the body.
If we are conscious in our speech and what we are vibrating, we can choose mantra, harmonious communication, and musical sounds that elevate, heal, and balance us.