The film stars British actor Ray Winstone as a man struggling to deal with the condition, which causes severe memory loss and confusion, and Wheeler insists he could not pass up the opportunity to get involved in the project because of his personal experience with the illness.
Wheeler was introduced to the film's director, Mat Whitecross, through his rocker pals Coldplay, who stepped into the role of producers for the movie.
He tells Britain's The Sun, "The main character in the film has Alzheimer's, as did my dad, who died two years ago. That's when I met the director of the film through the guys in Coldplay. I had seen dementia close up so it all seemed very fresh. I couldn't not do this project."