1. Parkinson's Disease Slideshow Pictures
2. Dementia Slideshow Pictures
3. Take the Parkinson's Quiz

Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Cognitive impairment in Parkinson's disease may range from a single isolated symptom to severe dementia.

• The appearance of a single cognitive symptom does not mean that dementia will develop.
• Cognitive symptoms in PD usually appear years after physical symptoms are noted.
• Cognitive symptoms early in the disease suggest dementia with Parkinsonian features, a somewhat different condition.

Cognitive symptoms in PD include the following:

• Loss of decision-making ability
• Inflexibility in adapting to changes
• Disorientation in familiar surroundings
• Problems learning new material
• Difficulty concentrating
• Loss of short- and long-term memory
• Difficulty putting a sequence of events in correct order
• Problems using complex language and comprehending others' complex language

Persons with PD, with or without dementia, may often respond slowly to questions and requests. They may become dependent, fearful, indecisive, and passive. As the disease progresses, many people with PD may become increasingly dependent on spouses or caregivers.

Major mental disorders are common in PD. Two or more of these may appear together in the same person.

• Depression: Sadness, tearfulness, lethargy, withdrawal, loss of interest in activities once enjoyed, insomnia or sleeping too much, weight gain or loss
• Anxiety: Excessive worry or fear that disrupts everyday activities or relationships; physical signs such as restlessness or extreme fatigue, muscle tension, sleeping problems
• Psychosis: Inability to think realistically; symptoms such as hallucinations, delusions (false beliefs not shared by others), paranoia (suspicious and feeling controlled by others), and problems thinking clearly; if severe, behavior seriously disrupted; if milder, behavior that is bizarre, strange, or suspicious

The combination of depression, dementia, and PD usually means a faster cognitive decline and more severe disability. Hallucinations, delusions, agitation, and manic states can occur as adverse effects of drug treatment of PD.

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