April 14, 2021

Parkinson’s Disease Symptoms – Neuropsychiatric Dysfunction


As we learnt in Parkinson’s disease early symptoms, Parkinson’s symptoms can be categorized into the 4 Cardinal Signs, Associated Symptoms and  Neuropsychiatric Dysfunction.

Neuropsychiatric Dysfunction associated with Parkinson’s can be viewed in terms of a patient’s state of mental well-being, and possible issues related to Dementia.

Mental Well-Being

A Parkinson’s patients mental well-being can be affected by a reaction to the disease, chemical changes in the brain e.g. research indicates acetylcholine is linked to a person’s mental state and serotonin to one’s mood, or the side effects of medications used to manage the disease (therefore may not be due to dementia noted later). This can affect the patients daily life, relationships and ability to socialize significantly. Aspects of mental well-being include:

  • Behavior, personality and mood alterations:
    • Antisocial or becoming withdrawn.
    • Apathy.
    • Anxiety.
    • Depression.
    • Hallucinations and delusions occur in approximately 5% of patients.
    • Impulse control issues e.g. cravings.


  • Cognitive disturbances :
    • Decreased attention span.
    • Executive dysfunction (executive function deficit (EFD): Ability to plan and execute appropriate actions.
    • Impaired memory and recall
    • Reduced mental:
      • Agility.
      • Clarity. Often described as a ‘dullness/dull thinking’
      • Flexibility.
      • Slowness (Bradyphrenia) including slow response to questions.
    • Visuospatial difficulties including facial recognition.




  • Depending on the source of data:
    • Between 30-40% of patients will experience some degree of cognitive impairment and memory problems. Some research suggests this rises to 80% after 8-10 years of the disease.
    • Between 1/5 and 1/3 of Parkinson’s patients develop some form of Parkinson’s Disease Dementia (PDD). The figure commonly quoted is around 20%.
  • The rate of progression and severity of dementia varies considerably between individuals.
  • Parkinson’s Disease Dementia typically takes 10-15 years to develop from initial Parkinson’s diagnosis. It is therefore considered to occur towards the later stages of the disease.
  • Parkinson’s disease patients have a  4- 6X greater risk of developing cognitive impairment or dementia than the general population.
  • Various issues arise regarding Parkinson’s Disease Dementia including:
    • Significant symptoms noted above in Mental Well-Being.
    • Increased mortality rate.
    • Reduced quality of life for patient and increased burden for family and carers/caregivers.
    • Nursing home care more likely.
  • It must be remembered that dementia symptoms can be caused by a variety of unrelated conditions and medications e.g. Vit B12 deficiency, underactive thyroid gland, depression, Alzheimer’s disease.

GENERAL OVERVIEW OF DEMENTIA : Description-Assessment-Types


The next article will consider the fundamental question of What is Parkinson’s Disease ?

Parkinson’s Disease Early Symptoms

Parkinson’s disease early symptoms may be subtle, go unnoticed and develop gradually over a number of years. A person will often feel ‘out of sorts’ and unable to pinpoint what exactly is wrong with them. It is not uncommon at this stage, for a patient to visit their practitioner and be told that they probably have a virus, are run down or suffering from stress.

Parkinson’s disease early symptoms may include:

  • Feeling ‘off-color’ or overly tired and worn out despite resting and sleeping.
  • Fatigue lasts more than 2 weeks.
  • Reduced sense of smell.
  • Irritable or depressed for no apparent reason.
  • Stiffness.
  • Aching.
  • Unsteady.
  • Executive dysfunction: easily distracted and difficulty with making decisions.
  • Losing track of a thought or word.
  • Significant weight gain/midlife obesity when a person was in their 40’s and 50’s.

Should any of the above signs persist longer than one would reasonably expect e.g. fatigue and feeling unwell due to a virus, most practitioners would begin to investigate the situation in order to determine if there was a significant underlying cause.

The type, severity and rate that Parkinson’s disease symptoms develop varies significantly between individuals e.g. although tremor or shaking is a classic Parkinson’s symptom, some people never experience it or only at the later stages of the disease. Therefore, aside from the general signs noted above, Parkinson’s disease symptoms can be categorized as follows:

  • 4 Cardinal signs: refers to the 4 major motor symptoms for diagnosis, namely:
    • Tremor.
    • Slow Movements (Bradykinesia).
    • Muscle Rigidity.
    • Postural Instability/balance disturbances (usually later stages).


The following points should be borne in mind regarding Parkinson’s disease symptoms:

  • Although most people will have a number of signs, a person does not need to exhibit all of the symptoms to be diagnosed with Parkinson’s disease.
  • Parkinson’s is usually unilateral (1 side) at the early stages progressing to bilateral (2 sides) as the condition worsens.
  • Given that Parkinson’s symptoms are highly individual, a patient will need regular medical assessment and medication will need to be tailored to the individuals needs.

Finally, it must be remembered that various non-Parkinson’s conditions can present themselves as having similar symptoms to Parkinson’s disease. Therefore, if a person is concerned that they may have Parkinson’s disease early symptoms, they should always consult a qualified practitioner for a professional diagnosis.