Dementia with Lewy bodies (DLB) Estimates for the number of people with DLB vary, but it is in the range of 10-15% of cases or about 100,000 people in the UK. The condition is named after Frederick H. Lewy, a neurologist who worked with Alois Alzheimer. DLB shares symptoms with both Alzheimer’s disease and Parkinson’s disease. This can involve problems with memory and thinking, but can also include hallucinations and tremors. Lewy bodies are abnormal deposits of a protein called a-synuclein in nerve cells, and are associated with cell damage. They are the underlying cause of several progressive diseases affecting the brain and nervous system, including dementia with Lewy bodies and Parkinson’s disease. Symptoms of DLB depend upon where the Lewy bodies are in the brain. If they are in the outer layers of the brain, this is usually associated with problems in mental abilities. At the base of the brain, they are more likely to cause the movement disorders associated with Parkinson’s disease.