The Angels hitmaker - who has been candid about his struggles with anxiety and being diagnosed with ADHD - is relieved to have been diagnosed with the neurodevelopmental condition, which can affect social communications, because he now has a "get out of jail free card" to explain his "weird" habits.
Speaking during a Q A at the Autumn/Winter launch of his clothing brand Hopeium's at Flannels, DailyMail Online reports he said: "I have ADHD and I just found out I have a bit of autism as well, which I actually f*****g love because it explains so much.
"It is my get out of jail free card now, and all the weird shit that I do I just say , 'Sorry I'm autistic.'
"With the ADHD you can completely and utterly concentrate on something 1000 per cent, but with absolutely everything else, you just cannot do it. Ask my kids."
The 52-year-old singer - who has four children with wife Ayda Field - has found it helpful to find a creative outlet in order to overcome his intrusive thoughts.
He said: "What I'm completely and utterly obsessed with is creating images and making funny things, if I'm creating images and funny things, I'm not thinking about me, because my brain is incredibly creative, and it can be creative about everything in the world that you panic or scared about.
"For example, this is how crazy I am. Recently, I was sitting on a plane, and I thought , 'What I can have telekinesis and my intrusive thoughts tell the plane to crash itself.'
"So that's the kind of level of insanity that I'm dealing with. It's best to train my brain to do something better than worrying about having supernatural powers and crashing a plane.'
In October, Williams claimed his intrusive thoughts were a form of "inside Tourette's", an inherited neurological condition, which impacts people through involuntary tics.
He told Paul Whitehouse and Dr Mine Conkbayir on their podcast I'm ADHD! No You're Not in an upcoming episode: "I've just realised that I have Tourette's, but they don't come out.
"They are intrusive thoughts that happen. I was just walking down the road the other day, and I realised that these intrusive thoughts are inside Tourettes. It just doesn't come out.
"Not only that, you would think that a stadium full of people professing their love to you would work as a distraction, but whatever it is inside me cannot hear it. I cannot take it in."
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