By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) - Growing up there was always a special feeling that was brought to mind just by mentioning the date December 7, after all the attack on Pearl Harbor had been called a day that would live in infamy – and it does.

September 11 conjures up similar feelings and for far too many within listening range it is far more personal and painful than that. Psychologists say that certain images can cause people to remember traumatic events and certain dates have the same effect.

For those of you who are having difficulty with memories today, it is recommended that you allow yourself time to reflect on the events and process them. But the recommendation is to also do something active to get a sense of normalcy, whether it is a day at work, a favorite hobby or some sort of exercise.