Most Parkinson 's disease patients suffer from some form of speech disorder. The researchers are convinced that, depending on the type of speech, it is possible to predict how Parkinson's disease will develop in a patient.

Parkinson 's disease causes the loss of brain cells that produce the transmitter nerve impulses dopamine.

Experts have not yet determined whether Parkinson's disease drugs, which are designed to replace dopamine in the brain, can affect the speech disorder.

The researchers managed to study 111 patients who completed a test consisting of several speech tasks. Special software assessed the parameters of their intonation, vocal quality, articulation and speech rate. The analysis led the researchers to define three types of speech disorders in patients with Parkinson's disease.

After a year of monitoring, the doctors found that patients with purely prosodic disorders had slightly improved speech because their defect was mild. The treatment was most effective in patients with voice disorders, while in patients with prosodic disorders, there was no apparent improvement.

According to the authors, this study showed that, based on the type of speech disorder, it is possible to predict how not only this symptom but also the overall disease will develop.