Lewy bodies are abnormal protein deposits found in the brain, primarily associated with neurodegenerative diseases like Parkinson's disease and Lewy body dementia. They are composed mainly of a protein called alpha-synuclein, which disrupts normal brain function and leads to various symptoms. The presence of Lewy bodies can cause a range of cognitive and motor issues, including hallucinations, confusion, and movement difficulties. These symptoms can vary widely among individuals, making diagnosis and treatment challenging. Understanding Lewy bodies is crucial for developing effective therapies for related conditions.