LSVT has been most researched for persons with voice and speech problems from Parkinson disease of unknown cause (“idiopathic Parkinson disease”). However, LSVT may also be useful for patients with atypical Parkinson disease, other types of neurological (brain/nerve) disorders, and possibly for patients with weak vocal folds in general.
Dr. Lorraine Ramig her colleagues have developed the LSVT. Prior to LSVT, a small number of clinicians had also developed techniques for voice and speech problems with Parkinson disease, which shared some similarities with LSVT (Scott and Caird, 1983; Robertson and Thompson, 1984).
LSVT is a very specific, intensive treatment program that emphases “loud” speech. In LSVT, therapy sessions are held daily for four days a week, for four consecutive weeks. Patients are also asked to practice therapy exercises outside the clinic. Every therapy and practice session involves work on loud sounds and phrases, and high and low notes. The new “loud” voice is then applied to functional tasks including conversation, talking on the phone, shopping, lecturing, etc. A critical aspect of treatment is that patients are taught to “recalibrate” (get used to) a new loudness level, because the loudness that they think is normal is actually too quiet. By getting used to the new loudness level, patients not only reacquire a louder voice than before, but their pronunciation and inflection also tend to improve as well.
When patients talk loudly, both vocal fold closure and articulatory precision in speech tend to improve. There seems to be something special about voice in the brain’s hierarchy of speech control: loud voice generates improved pronunciation, but the reverse is apparently not true. In fact, by talking “loudly” patients not only tend to be heard and understood better due to stronger voice and articulation; for many patients, facial expressiveness also tends to improve. Therefore, patients who have received LSVT often seem more involved in communication than before treatment.