What is Parkinson’s Disease?

Parkinson’s disease (PD) occurs when brain cells that normally produce dopamine stop working or die. The death of these cells leads to abnormally low levels of dopamine, a chemical which helps relay messages between areas of the brain that control body movement. PD is called a movement disorder due to the following typical motor symptoms:

  • Stiffness (rigidity)
  • Slowness (bradykinesia)
  • Resting tremor
  • Balance and coordination difficulties (usually occurs later in the disease)1

Non-motor symptom also occurs with PD, and can often precede motor symptom by up to a decade.2 Non-motor symptoms may include:

  • Sleep disorders
  • Constipation and continence issues
  • Mood Disturbance
  • Cognitive issues3

Other physical changes include speech problems and swallowing problems.4

Symptoms of PD, and the way they progress will vary from person to person. Appropriate treatment can have a significant impact on how well a person lives with PD.


Treatment for PD involves a combination of medication and therapies, to address the wide range of symptoms:

  • Oral and advanced therapy medications.
  • Surgical treatments including deep brain stimulation (DBS).
  • Allied Health therapies including Physiotherapy, Occupational Therapy, Speech Pathology, Dietetics, Psychology and Social Work.5

The Role of Speech Pathology

Most people with PD will experience changes in speech, voice and swallowing at some point during the course of the disease. 90% of people with Parkinson’s are at risk of developing a weak voice that can lead to serious speech and swallowing difficulties.6

Some of the most common changes to speech and swallowing in PD include:

  • Quiet, soft voice or voice trails off
  • Reduced intonation and emotion conveyed in voice
  • Reduced intelligibility – mumbled speech
  • Altered speech rate – may be slow, or festinating (speeds up)
  • Pooling of saliva
  • Difficulty eating and drinking

Cognitive changes may also impact on communication e.g. word finding difficulties.

Speech Pathologists have a crucial role in the assessment and management of communication and swallowing disorders.

Visit the below sites to find more information about Parkinson’s disease:

1, 3, 4 Content sourced from The Michael J Fox Foundation
2 Content sourced from Shake It Up Australia Foundation
5 Content sourced from Parkinson’s Australia
6 Content sourced from Parkinson Voice Project