Researchers said subtle shifts in our senses of sight and smell could offer early signs to Alzheimer's disease prior to memory symptoms start surfacing. They presented the new data this week at the Alzheimer's Association International Conference in Toronto.

CBS News medical contributor Dr. David Agus observed that apparently the nose and the eyes are window to the brain.

According to one of the studies, a thinning of the retinal nerve fiber layer in the eye has probability to occur in people with poor performance in testing of cognitive skills such reasoning, memory, and reaction time.

On ‘CBS This Morning’, Agus said that the discovery makes sense. Agus added, “If you look in the eye, the retinal nerve that comes out of the brain, if it gets narrower, that's an indicator of the onset of Alzheimer's”.

Another study, based on the sense of smell, included a panel of 40 scratch-and-sniff surfaces wearing different familiar scents like bubble gum, turpentine, lemon, licorice, and even ‘eau de skunk’.

Agus added that in case an individual can identify more than 35 of them, he has a quite lesser chance of progressing to Alzheimer's. Less than 35 is an indication of the disease’s onset.

He mentioned that not just the nose sensitivity diminishes, rather with the development of cognitive impairment the brain fails to identify what those smells are.

Researchers are hopeful that such test may ultimately result into an easier way to precisely diagnose Alzheimer's well in time, offering a welcome substitute to forcibly getting injections and undergo imaging of the brain, like radiation exposure.

Another latest study, presented at the Alzheimer's conference, came up with an idea of possibility of warding off Alzheimer's by training brain with a specially-designed computer game.