Elderly dogs can suffer from cognitive dysfunction, similar to dementia in humans. Evan MacLean with the Arizona Canine Cognition Center in Tucson explains how games and puzzles that provide mental stimulation for dogs helps researchers understand how human brains respond at an advanced age.

The saguaro cactus has been a source of study for southern Arizonans for decades. Saguaro National Park wildlife biologist Don Swann is among the scientists asking why saguaros are biologically fit to survive the ongoing drought, and looking deeper into its role in the desert ecosystem.

Our cognitive abilities change as we grow older.