Are my memory lapses a sign of Alzheimer's?

Q: I am in my late 50s and I’ve noticed that my memory, and even my ability to concentrate, is not the same as it used to be. How do I tell the difference between memory changes that are a “normal” part of aging and changes that may signify the onset of a dementia such as Alzheimer’s disease?

Answer:
These kinds of personal observations regarding reduced memory efficiency and susceptibility to distraction are fairly common as we age. Research into the memory changes characterizing normal aging shows that our ability to encode information into memory starts to decline gradually beginning as early as our 30s. So if you’re in your 50s you might not remember quite as many details from a recently read newspaper article as you could in your 20s. However, your ability to keep the details you have learned is pretty stable throughout adulthood.

The biggest difference between older and younger adults is with the retrieval of stored information. The name or fact is stored in your brain, but you just can’t access it when you need it. Later, when the pressure is off, the information might come to you. This type of failure to retrieve a piece of information at the time you need it, such as remembering someone’s name, is the most common memory complaint associated with aging.

The changes in memory acquisition and retrieval as you age are cumulative and subtle; often many decades will go by before you become aware of these changes. A recent neuroimaging study, led by Dr. Cheryl Grady at Baycrest’s Rotman Research Institute in Toronto and published in the February, 2006, Journal of Cognitive Neuroscience found that there are age-related differences in brain-memory activity that begin gradually in middle age (between ages 40 and 60). The good news is that the changes are subtle, with relatively little impact on performance level.

The changes in memory activity become more pronounced in older adults (65-plus), and include regions in the brain believed to play a role in our ability to ignore distracting information. These regions show reduced activity when older adults engage in memory tasks, a finding consistent with results from previous studies showing increased susceptibility to distraction as we age. So, you may find you need to turn off the radio when you are engaged in a complex thinking task, such as doing your finances, while the teenager in your life can listen to an iPod while studying for an exam without difficulty.

At what point do memory changes become a cause for concern? Memory mistakes happen to all of us from time to time. We have all experienced going into a room and wondering, “Now, what did I come in here for?” Is making a memory mistake as an older adult potentially more significant than when we are younger? The answer is no. What might speak to significance is whether there seems to be a notable increase in the frequency of everyday memory slips and whether these slips have real consequences.

For example, if you are low on sugar in your cupboard and intend to make a birthday cake, then forgetting to buy the sugar at the grocery store means you have to make another trip. This occasional slip is no big deal. Similarly, forgetting you have a lunch date next week and committing to another activity is okay if you catch the error, but not okay if you stand up your lunch date.

As we age then, an increase in memory failures that have consequences, ranging from annoying (repeat trip to the grocery store) to more significant (standing up your lunch date) should grab our attention. You might wonder: Does this signify the onset of Alzheimer’s disease?

First, rule out all other possible causal explanations. A visit to your family doctor can assist in determining whether or not there is a physical explanation for reduced memory function. Consider what is happening in your life. Stress, mood, poor sleep, whether or not you happen to be pre-occupied or distracted: all these can reduce memory efficiency.

In short, some memory changes, such as reduced ability to retrieve a name or fact, are a normal part of aging. An increased tendency to make everyday memory failures that have real consequences may not be normal. However, you should consider whether there may be other physical or psychological factors, unrelated to dementia risk that could also explain these mistakes.

One thing you can do, regardless of whether or not you feel your memory is poorer than your same-aged peers, is to utilize memory strategies. Written reminders are a common strategy employed at any age, but there are many other strategies that research has shown can be effective. If you are interested in improving memory efficiency, check senior centres and hospitals within your community to see if they offer information on memory tips or workshops.

Educating yourself about practical memory strategies, and routinely applying them, can improve everyday remembering and may even delay the onset of dementia in those at risk.

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Dr. Kelly Murphy is a psychologist with Baycrest’s Memory Intervention Program. For more information on memory and aging, go to www.baycrest.org/memoryandaging