Hypophonia is soft speech, especially resulting from a lack of coordination in the vocal musculature.[1] This condition is a common presentation in Parkinson's disease.[2] This condition is generally treated with voice training programs, use of shorter sentences, breathing exercises, and muscle training exercises for vocal cords.[3][4]
Further research
Doctors at the Indiana University of Pennsylvania have proposed a novel treatment for hypophonic voice: Twang therapy.[5]