People suffering from dementia are often able to remember their past but forget most recent events. This occurs because the brain damage from dementia makes it more difficult to encode new memories. However, this same damage also impairs a person's ability to remember where information comes from and whether or not it is reality.
For example, have you ever had a dream that felt so real that you questioned, for a brief moment, whether it was a dream or a memory? Healthy brains can usually make the distinction by identifying where the information came from and evaluating whether it actually happened. However, for those with dementia, the brain is unable to make this distinction. Pieces of information that actually came from the TV, a novel, or a dream may seem like part of a real-life event to a person with dementia.
Nancy Dennis, a cognitive neuroscientist at Penn State who studies false memories, says there are two types of memory problems in older people, both equally common. One is simply forgetting. You go to the grocery store and forget if you need milk or not. The other is false memories. You are certain that milk was on the grocery list when it was not.
Researchers do not know at what age false memories become more common. Yet, research has revealed that people over 65 more often have false memories and do not realize it. "We are very much aware of forgetting, because we know it happens," says Daniel Schachter, who researches memory at Harvard. "We are much less aware of memory distortion, where memory is there, but wrong."
As we grow older, we tend to become more confident in our memory, even though it is less accurate. In addition, older people tend to rely on the broad parameters for a memory but not the details. Usually, this does not affect a person's day-to-day life, but it is a sign of brain deterioration.
The hippocampus, which is an integral part of your brain for storing new memories, starts shrinking in many people as they age. It is also attacked early on by Alzheimer's disease. Many older people begin using other parts of the brain to compensate for the diminished hippocampus. Unfortunately, this compensation does not work as well and eventually the other parts of your brain decline as well.
When someone you love with dementia begins relating memories you know to be false, it can be confusing (and scary) to tell them the truth. Once a false memory takes hold in a person, it is hard to correct the matter. The more a person relates a false memory, the firmer the memory becomes in their mind.
Although these false memories can be frustrating to family and caregivers, it is important to understand why these false memories are occurring. Some people may benefit from a memory box, which can help a person recall past events and people. You can find helpful tips and information in our articles How to Communicate When They Have Alzheimer's and Successfully Dealing With Difficult Dementia Behaviors.
Source: False memories add to dementia frustrations by Stacey Burling in The Journal Gazette