Causes. Researchers are still struggling to concretely identify the specific causes of Lewy body dementia. However, trends have been reported and recorded. Most people diagnosed with Lewy body dementia do not have a family history of this specific disorder, ruling out genetics as a prime indicator. Research has shown that this type of dementia is typified by an abnormal buildup of proteins. These deposits are called ‘Lewy bodies’- proteins which are often associated with both Parkinson’s and Alzheimer’s disease. Those with Lewy bodies present in their brains have also been shown to have the same structural neural tangles and plaques that are commonly associated with a person with Alzheimer’s disease.