According to this link:
http://www.memorylossonline.com/winter2010/memorynews.html

They are saying the rat that eats fat-food diet took longer to finish the maze and made more mistakes..

any thoughts?

The article doesn't state what kind of fat was used in the experiment. There are good fats and bad fats and without testing the effects of both, the study is pretty meaningless.

Also, the study is titled, “Deterioration of physical performance and cognitive function in rats with short-term high-fat feeding."

Perhaps the problem is the "short term" part. Any time you make a radical change to a daily diet there is a transition period where nothing works very efficiently as the body tries to adjust to its new diet. Maybe 5 days wasn't long enough to allow the rats fed a "high fat" diet to acclimate.

Any way you cut it, the study is pretty useless.

That is like feeding a group of people just grass for a few months, and then saying that grass must be unhealthy for cows, as all the people died.

HAHAHA i literally laughed out loud on your comment samjohn..nice!