Anyone who knows me well or, more particularly, talks with me in the afternoon or evening knows that my conversation then is peppered with such phrases as, “Oh, what is that word?” or “Well, I don't recall the name right now; maybe it will come to me later” or “Never mind, I forgot where I was going with this train of thought.”
It has been thus for so long now that I warn people: “We shouldn't try to do anything that takes brain power after about 2PM because by that time of day, I get stupid.”
It's not an excuse. It's true that I am much smarter in the morning and get more stupid as the clock hands pass noon.
This is a large impediment to accomplishing the work that matters to me: this blog and the Villages development that alone more than fill eight hours of every day.
In addition, my physical strength and energy wane at about the same pace so each day is a scramble to get everything done (blog and Villages work, the daily exercise program, shopping, bill paying, cooking, cleaning - you get the idea, pretty much anything other than lying about as a slug) before 3PM or so.
The difference in my capabilities between morning and afternoon/evening is so pronounced, it is almost like I am two different people. Now, science has provided me with a possible explanation.
"'Time of day really does matter when testing older adults,' says lead author John Anderson. 'This age group is more focused and better able to ignore distraction in the morning than in the afternoon.'
“He and his colleagues note that their study provides the strongest evidence yet that there are measurable differences throughout the day in brain function for older adults.”
John Anderson and his colleagues at the Rotman Institute at Baycrest Health Sciences and the University of Toronto published their results in the journal, Psychology and Aging.
It's a small study so more work may be needed. Nevertheless, the differences between ages and time of day are clear.
The initial study involved 16 young adults between the ages of 19 and 30, plus 16 older adults between the ages of 60 and 82. Between 1PM and 5PM, each person was given a sequence memory test while irrelevant words and pictures appeared on a screen as their brains were scanned with fMRI:
”The older adults who were tested in the afternoon showed signs of 'idling,' the researchers say, which means they were showing activations in the default mode - a set of regions that are activated when a person is resting or thinking about nothing in general.
“This could indicate that the adults were having a hard time focusing, because when a person is fully aiming their attention at something, resting state activations are suppressed.
“[However,] the team found that when another group of 18 older adults was tested in the morning between 8:30 and 10:30 am, they performed significantly better.
“In detail, they focused on fewer distracting items than their peers who were tested in the afternoon, and they even closed the age difference gap in performance with the younger adults.”
It has been known for awhile that old brains are more easily distracted than young ones, that elders commonly have more trouble focusing. And increased forgetfulness in old age (without dementia) even has its own name – senior moments.
Except for my daily personal experience, this is the first I have found that the time discrepancy may be a natural phenomenon of aging. And of course, as the authors point out, these results have important consideration for all cognitive research in elders:
"[Dr. Lynn Hasher, senior author on the paper,] adds that ignoring time of day when testing older adults on certain tasks 'may create an inaccurate picture of age differences in brain function.'"
In my case, maybe I've always had an old person's brain; the afternoon decline has been a difficulty for most of my adult life. I was in my mid-30s when my boss joked one day to the rest of the staff, “If you need Ronni to do anything, you'd better ask her before 3PM.”
Although I had not paid attention before then, when she said it, I knew she was right. It seems always to have been so that my mind slows way down not long after lunch.
At The Elder Storytelling Place today, Arlene Corwin: Word of Mouth