Hope for those suffering from Alzheimer’s disease could be closer than previously thought.

Researchers at the University reversed memory loss in mice with significant brain degeneration for the first time, suggesting that it is possible to recover the ability to remember things.

While similar to senile dementia, Alzheimer’s usually starts in people’s 50s or 60s. Its first symptoms are impaired memory, which is followed by impaired thought and speech, and finally complete dependence. The disease affects an estimated 4 million people in the United States.

The mice were tested by inducing dementia through genetic engineering to make them express a human protein called tau, which is accumulated in the brains of patients with Alzheimer’s disease as neurofibrillary tangles.

The researchers further designed the mice so the human gene that has been expressed in the mice could be “turned off” using food supplements, according to the study.

The researchers predicted memory loss to stabilize when the transgene expressing the dementia was turned off, the according to the study.

Researchers tested the mice by placing them in a pool with a platform.

According to the study, because mice are not fond of water, they swim to find the platform.

The mice first learned where the platform was located, then, the platform was removed and the mice were again put in the pool.

The researchers measured the amount of time the mice spent swimming in the area where the platform should have been before and after the dementia was deactivated.

Martin Ramsden, a research associate who worked on the study, said the results surpassed their expectations. The mice regained memory of where the platform was.

“We did not believe a severely demented mouse, lacking more than 50 percent of the brain cells responsible for learning and memory, could recover to a point close to control,” Ramsden said. “No one has previously shown that these memory deficits are reversible.”

This study suggests the neurofibrillary tangles are not a cause of dementia as previously thought, Ramsden said. Neurofibrillary tangles are now considered end markers of Alzheimer’s disease, he said.

Mary Birchard, executive director of the Alzheimer’s Association Minnesota-North Dakota, said the discovery is a huge step in treating Alzheimer’s disease but will need more money and more time for tests on people before it can be effectively used.

“It’s exciting and it gives all of us who work with Alzheimer’s every reason to believe that we’re making significant progress towards a world without Alzheimer’s,” she said.