Robin Williams' suicide 'was caused by hallucinations from a devastating form of dementia' he was battling alongside Parkinson's

• Court documents reveal Williams suffered from dementia with Lewy bodies
• Sources say disease was the 'key factor' that drove him to take his own life
• Legendary comic was found hanging from a belt at his home last August
• Hallucinations are common among those affected by Lewy bodies dementia

Robin Williams' suicide could have been triggered by a common but devastating form of dementia that may have disrupted his normal brain function.

Court documents obtained by TMZ reveal that Williams, who was found hanging from a belt at his home in California last August, was suffering from dementia with Lewy bodies.

Sources connected with the troubled comic's family told the news site that the degenerative disease was the 'key factor' they believe drove him to take his own life.

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Robin Williams was found hanging from a belt at his home in California last August. It has emerged that the actor was was suffering from dementia with Lewy bodies

Hallucinations and delusions are common among those affected by Lewy bodies dementia, and sufferers often struggle to identify friends and family. The disease also typically causes problems with attention and alertness. 

'The condition itself is caused by the build-up of protein into clumps, called Lewy bodies, in the brain, which can damage nerve cells in areas involved in memory and thinking,' explained Hilary Evans, Director of External Affairs at Alzheimer’s Research UK. 

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