Quick quiz: which memories are most easily forgotten?

Not all memories are created equal. Some are indelible, others fleeting. That means not all forgetfulness is worrisome. The following scenario may help explain this.

Imagine that you are 65 years old. You get in your car to drive to your sister's house in another town for Thanksgiving. The last time you had Thanksgiving dinner at her house was five years ago. That was your Uncle Ed's last holiday with the family — he died three months later. Uncle Ed's new caregiver, Pat, had brought him to the dinner. That was also the Thanksgiving your niece announced she was pregnant. On this trip to your sister's, which of the following are you most likely to forget?

A. To release the parking brake before setting the car in motion

B. Your uncle's name

C. The name of your uncle's caregiver

D. The family's reaction to your niece's news

E. The route to your sister's house

F. To put in the car the pumpkin pie you promised to bring

Answer: If you have normal age-related memory problems, the correct answers are C and F.

Let's review:

A. The steps involved in driving a car are procedural memory, which holds up quite well with age.

B. If you have trouble remembering your uncle's name, this is a sign that something more serious may be wrong. You should consider having your memory checked by a doctor.

C. The name of someone you met only once several years ago is something that is less likely to be remembered. When you met Pat, you may have put the name into short-term memory and it never made into long-term storage. So you will not remember it five years later. Even if you did store the name, you haven't used it for so long that the memory of it has faded. If you saw Pat on the street, you would most likely recognize her but not remember her name. If she introduced herself, it would likely spark the memory and allow you to connect the name to the face.

D. Recollection of the interaction among the family members at the dinner is an example of episodic memory. Some types of episodic memory diminish with aging. But memories of events that provoke emotion tend to endure. You may have more trouble remembering a mundane conversation you had with your cousin than the news about your niece's pregnancy.

E. You could have answered E as something likely to be forgotten and been right. This was a trick because there's not enough information in the question. If you visit your sister often, then you should remember how to get to her house. Getting lost is a sign of a memory problem outside the realm of normal, and you should consider having your memory checked by a physician. If it's been five years since you drove there, you will likely need directions or a GPS. As you drive, though, you may find that you don't need as much prompting as you thought. You may see landmarks that jog your memory.

F. How could you possibly have forgotten the pie? There are several possible reasons for this lapse that have nothing to do with dementia. Distraction is an example. You may have been thinking about other concerns while packing for the trip. Perhaps the phone rang while you were loading the car. You chatted with a friend for a few minutes and then forgot that you hadn't put the pie in the car.

From Improving Memory: Understanding age-related memory loss