Researchers say a drug already approved by U.S. regulators to treat high blood pressure may also help to reverse age-related memory declines.

The drug is called guanfacine and clinical trials are underway at Yale University in Connecticut to confirm its beneficial effect in enhancing so-called working memory in older adults.

Yale neurobiologist Amy Arnsten says working memory is the building block of all higher cognitive functions, underlying things like abstract thought and executive functions including multitasking - juggling several activities at once. Arnsten says working memory starts to decline in a person’s 40's.