Julianne Moore on what makes Alzheimer's movie Still Alice so compelling

Julianne Moore didn't know much about Alzheimer's before taking on the role of Dr Alice Howland in Still Alice.

"I was really starting at zero," the actress admits in a recent interview at the Four Seasons Hotel. Adapted from Lisa Genova's bestselling book, the tender and occasionally harrowing drama tells the story of a Columbia University linguistics professor who discovers that she has early onset Alzheimer's.

"What was so compelling about the script was that it was the first time I had seen a disease like this depicted objectively. It's usually from the point of view of the caregiver or a family member who's watching someone transform in this way. This brings you inside this character and her journey through it," Moore says.

The actress told co-directors and writers Richard Glatzer and Wash Westmoreland at the start that she didn't want to represent anything on screen that she hadn't actually seen. Whether it's using a highlighter so as not to lose your place in the middle of a speech or self-administering a daily memory test on your iPhone, everything that Alice does in the movie is based on reality.

"I felt like that was the only fair way to do it," she says. She immersed herself in the world of Alzheimer's through books and documentaries that she, Glatzer and Westmoreland would pass around to one another, but also by talking to clinicians, neurologists and patients.

Moore started at the national level, conducting Skype calls with patients the Alzheimer's Association put her in touch with. She had a doctor administer an extensive cognitive test on her at New York's Mount Sinai Hospital. She consulted with gerontologists.

During her sojourns to long-term care facilities and support groups, Moore found herself struck by the generosity of everyone she spoke to in the process and observed that people's personalities were very evident, no matter how advanced their disease.