The heartbroken widow of actor Robin Williams revealed the relief she felt when he was diagnosed with Lewy body dementia after his death by suicide in 2014.
Susan Schneider, 56, spoke to the Today show in an interview broadcast Tuesday in which she discussed the 'invisible monster' that chased her husband in the last years of his life, as they played 'whack a mole' with his symptoms.
The legendary comedian was diagnosed with Parkinson's disease three months before his death, aged 63, but he was actually suffering from Lewy body dementia.
Experts say the disease had such devastating effect on Williams' brain that they are surprised he could still walk and talk before his death as Schneider now works to promote awareness in his honor.
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On Tuesday, the late great Robin Williams' widow Susan Schneider discussed the 'invisible monster' that caused him to take his life by suicide, at age 63, six years ago
Schneider added she was 'relieved' to learn its name after playing 'whack a mole' with Williams' symptoms not knowing the cause. Pictured, Schneider and Williams
Brain scan: The legendary comedian was diagnosed with Parkinson's disease three months before his death, but he was actually suffering from Lewy body dementia
'Robin and I knew there was so much more going on. Robin was right when he said to me, "I just want to reboot my brain,"' the landscape painter told Today's Hoda Kotb.
'I was called in to sit down to go over the coroner's report. They sat me and down and said he essentially Robin died of diffused Lewy body dementia. They started to talk about the neurodegeneration. He wasn't in his right mind.'
She continued: 'I was relieved it had a name. Robin and I had gone through this experience together, really being chased by an invisible monster. And it was like whack-a-mole with the symptoms. I left there with a name of the disease, the thing that Robin and I had been searching for.'
Following Williams' tragic death, rumors circulated about the cause which Schneider described as 'challenging' to read about the 'greatest love I've ever known, my best friend, my partner'.
Lewy body dementia (LBD) is the second most common form of degenerative dementia after Alzheimer's.
Unlike Alzheimer's, LBD affects the brain regions responsible for vision - as opposed to memory.
That means sufferers may start with memory loss, but over time the more debilitating symptoms will be powerful hallucinations, nightmares and spatial-awareness problems.
LBD is closely connected to Parkinson's disease, meaning that many sufferers will develop Parkinson's as well - as happened to Robin Williams.
She now hopes that new documentary 'Robin's