Alzheimer’s researchers create ‘Forrest Gump’ mice

LONDON, Ont. — Western University scientists call their creations Forrest Gump mice because they can run great distances but are puzzled by simple tasks.

But beyond their novelty, they serve as a cautionary tale for neuroscientists trying to combat the scourge of Alzheimer’s disease.

Scientists know people with the disease lose neurons that produce a key chemical (acetylcholine) that serves as a traffic cop of sorts for signals sent through the brain.

So the researchers decided to see what would happen if they modified mice to produce more acetylcholine.

“The response was the complete opposite of what we expected,” researcher Marco Prado said. “It’s not a good thing. Acetylcholine release was increased threefold in these mice, which seemed to disturb cognitive function. But put them on a treadmill and they can run twice as far as normal mice before tiring. They’re super-athletes.”

The mice failed miserably on a test in which they were rewarded for remembering where a light flashes on a computer tablet — unmodified mice did significantly better.

Prado’s research is published in the Journal of Neuroscience. He believes the tests show acetylcholine in normal amounts helps people differentiate between things, but flooding the brain with the chemical makes it very difficult to discern what is important.