They were assessed to ensure they had not suffered any mental decline before the study began, and were assessed regularly during the trial.

BBC: Genetic clue to Alzheimer's risk

The experts aren't sure yet, but people with migraines don't seem to be at greater risk of memory loss or mental decline as they age.

CNN: Women's migraines linked to higher stroke, heart attack risk

After 18 months, the average mental decline in the DHA and placebo groups was nearly identical, as measured on two separate tests and rating scales.

CNN: Fish oil ingredient doesn't slow Alzheimer's

Several studies that followed large groups of people as they aged have suggested that a diet rich in fish is linked to a reduced risk of dementia and mental decline, but most randomized controlled trials comparing DHA supplements with placebo have found no benefit.

CNN: Fish oil ingredient doesn't slow Alzheimer's

Research shows that eating approximately 3 servings per day of vegetables is associated with 40% less mental function decline.

CNN: How does nutrition affect dementia?

If it works, it could be the first drug to slow patients' mental and functional decline.

WSJ: CEO: Risks key for Merck to succeed, help patients

Fish consumption is associated with significantly less decline of mental function and lower risk of Alzheimer's disease.

CNN: How does nutrition affect dementia?

"In principle, if you can get the NGF into the brain successfully, this could offer a way of slowing down the decline of mental abilities in patients with Alzheimer's disease, " she said.

BBC: NEWS | Health | Alzheimer's gene therapy hailed

About 30 states have reduced mental health spending since 2008, when revenues were in steep decline, according to the National Alliance on Mental Illness.

NPR: After Shootings, States Rethink Mental Health Cuts