The precise cause of LBD is unknown, but scientists are learning more about its biology and genetics. For example, we know that an accumulation of Lewy bodies is associated with a loss of certain neurons in the brain that produce two important chemicals that act as messengers between brain cells (called neurotransmitters). One of these messengers, acetylcholine, is important for memory and learning. The other, dopamine, plays an important role in behavior, cognition, movement, motivation, sleep, and mood.
The most common symptoms include changes in cognition, movement, sleep, and behavior. This may depend on which of the 7 stages of lewy body dementia https://myallamericanhospice.com/what-are-the-stages-of-dementia/
People with LBD may not have every symptom associated with the disease. Any sudden or major change in functional ability or behavior should be reported to a doctor.