Alzheimer's blog

Procedural memory remains robust as dementia develops

By Angela Lunde August 20, 2013

Most things written about Alzheimer's describe the condition in terms of deficit and loss, and suggest that persons living with the disease can no longer learn or live meaningful lives.

My last post hopefully begins to draw attention to this misconception. Persons living with dementia maintain many abilities including the preservation and often enhancement of creative abilities as well as the capacity to learn.

One place where learning in the face of cognitive impairment comes alive is in the Mayo Clinic Healthy Actions To Benefit Independence and Thinking (HABIT) Program.

Persons living with memory loss and their support partners come to the program to learn new skills to compensate for memory loss through calendar-based training and to practice lifestyle habits aimed at optimizing brain health.

What's so rewarding about HABIT and other similar treatments is we validate that persons living with memory loss can actually learn when certain memory systems of the brain are involved. Fortunately, the brain is not a single entity but a combination of multiple functions with generally two prevailing memory systems.

One memory system is known as declarative or explicit memory; think of it as the "knowing what." It's memory of facts and events, and refers to those memories that can be consciously recalled. It's when something happens, or some information comes in, and we can later recall that event or information.

People with mild cognitive impairment and dementia such as Alzheimer's experience profound loss in declarative memory. Ask them to recall facts about a recent event, a conversation they had or something they recently read, and they probably won't succeed.

A second memory system is known as procedural or implicit memory; think of it as the "knowing how." It's the unconscious memory of how to do things created by repeating an activity over and over again so it occurs automatically — brushing teeth, writing our signature, or knowing the words to the hymns in church. They are well-rehearsed, almost unconscious, behavioral routines.

The good news is that procedural memory remains robust in the face of early memory loss and even into dementia. This means that a task or activity that has been repeated or practiced over and over can be remembered.

Imagine you've been an avid golfer most of your life and then develop dementia. You're likely to be able to play the game for quite some time because the habit of knowing how remains intact (choosing the iron or wood, swinging the club) in procedural memory. However, recalling the shot you just made, knowing when or what, may be forgotten as part of declarative memory.

Cameron J. Camp, Ph.D., a noted psychologist specializing in applied research in gerontology developed a research-based approach to Alzheimer's called "spaced retrieval" which, similar to the learning system in HABIT, employs procedural learning. Using repetition and repeated success, persons with Alzheimer's learn to remember.

Dr. Camp asks a group of caregivers at residential memory care facility, "What happens when you seat someone in Mary's chair in the dining room?" When someone in the audience says, "Mary gets angry," Dr. Camp nods, agreeing.

Mary couldn't tell you what seat in the dining room is hers or even show you when asked because that would draw from the conscious declarative memory system. Yet, having been directed to the same dining room chair for several months since moving into the facility, Mary's brain learned the unconscious process of finding her spot in the dining room because her procedural memory remains healthy. Mary can learn.

Now, there is another memory system that remains beautifully intact in persons living with Alzheimer's and other dementias called emotional memory — more on that next time.

- Maria Montessori

Aug. 20, 2013