The former First Lady is credited with raising awareness for the disease and added a personal face for the call for more research.
"For this to happen in the 90s when people weren't even talking about it, it really was not only heroic, but such a benefit," said Maria Carrillo, the chief science officer of the Alzheimer's Association
Carrillo said Nancy Reagan, who passed away on Sunday at age 94, was courageous to bring attention to the disease.
"When a disease really hits you in your mind and personality and takes away who you are as a person, it is a very personal disease and personal choice whether you're going to share it with the public," Carrillo said.
After leaving Washington, D.C., the former First Lady broke with conservatives by advocating for stem cell research for Alzheimer's disease.
President Barack Obama and First Lady Michelle Obama recognized her perseverance in a statement that read: "She became a voice on behalf of millions of families going through the depleting, aching reality of Alzheimer's, and took on a new role, as advocate, on behalf of treatments that hold the potential and the promise to improve and save lives."
Over the years, Reagan's tireless efforts to fight the disease helped bring national attention to the disease.
"It really brought his disease out of the shadows," Carrillo said. "It was not talked about at all and since then has slowly continued to gain public awareness."