But of all the aspects of his performance, it was that haunting laugh that’s probably stuck with viewers the most. In the movie, Arthur Fleck suffers from the Pseudobulbar Affect, a mental disorder that causes him to laugh uncontrollably. And one man who really felt Phoenix did a great job with the role, is Scott Lotan.

For Scott Lotan, the pseudobulbar affect, or PBA, is a symptom of his multiple sclerosis. Much like Arthur Fleck, the disorder causes Mr. Lotan to break into uncontrollable fits of laughter that can last up to 10 minutes.

In a conversation with LADbible, he said the disorder often lands him in uncomfortable situations.

“I have had issues with not being served at restaurants and been asked to leave because waitstaff were uncomfortable. Many times if I am out for a drink with friends, there is someone with low self-esteem that believes I am laughing at them and they will try and start a fight.”

Just like it was for Arthur Fleck in Joker, Scott Laton often finds himself in very awkward situations due to PBA. There was one instance when PBA struck after a tragic crash in 2003.

“We were leaving my engagement party and were hit by a drunk driver. My fiancée died at the scene with my mother’s death three days later. I remember being at the scene laughing and being questioned by police. At the wakes for both my mother and my fiancée I would have to separate myself from everyone as I would burst into laughter at times.”

That incident gives us just a hint of the difficulty Scott Laton must go through due to his disorder.

Joker brought the little-known disorder into the mainstream, and Mr. Lotan is appreciative of it and Phoenix’s performance.

“I think he did a great job of capturing the inability to stop laughing no matter what the circumstances are. I felt as if he experienced a deep sense of rejection in the bus scene, similar to how I felt during the days of my accident. It weighs heavy on the mind, people just look at you. You try and explain but they have preconceived notions that you are a drug addict or just a deranged lunatic.”

“I think he captured the feeling of isolation and frustration with the lack of understanding from others. At times during the film I felt as though I was looking at a reflection of myself.”

While videos of him experiencing such episodes have gone viral on the net, according to LADbible, Mr. Lotan is keen to emphasis that his life is not without hope.

“There are a lot of comments of empathy [online], and although they are offering well wishes, they also seem to think I am living this horrible life filled with pain and suffering. Just like anyone else I have my ups and downs – sure, at times I laugh uncontrollably, but there could be much worse things to happen.”

“For the most part it turns into a humorous thing when interacting with my kids.”