Oscar nominee Julianne Moore says her heart-wrenching performance in Still Alice, is based on real dementia sufferers and inspired by the struggles of its co-director who has motor neurone disease.

Moore, who is tipped to win best actress for her performance as a linguistics professor with early-onset Alzheimer's disease, said the experience of Richard Glatzer and his co-director and husband Wash Westmoreland "parallel" the film's story.

Glatzer, who was diagnosed in 2011, deteriorated so badly by the time the film was made he could only communicate with an iPad.

Speaking to the Telegraph magazine, Moore described the progress of the disease as “very rapid and, of course, heartbreaking”.

She added: “What [Westmoreland and Glatzer] were experiencing as a couple was kind of a parallel story to what was happening in the film, which is: how do you live your life when you are dealing with a progressive degenerative disease? What’s valuable to you, how do you deal with your friends, your loved ones, your job?”

Based on a 2007 book by Lisa Genova, Still Alice has already netted Moore a Bafta and Golden Globe.

She said her greatest concern in making the film was getting the disease right, and made sure she worked “from top to bottom” to research the role.

Through the USA’s national Alzheimer’s Association she met several women across the country who had been diagnosed with early-onset Alzheimer’s, which means younger than 65.

These included Sandy Oltz, who was diagnosed at 45 and spent her 50th birthday on set.

She met carers and patients through the New York branch of the Alzheimer's Association too, and visited a long-term care facility where people were in the late stages of the disease.

She said: “Everything that you see in the movie, all the physical behaviours, the emotional behaviours, those are all things I had seen people do or they had spoken about to me directly.”

Still Alice is released on March 6th.

PA