I was thinking yesterday about all the things that go on in our lives, too many and varied to record.

That led me to think about Dr. Wilder Penfield, the famous Canadian neurosurgeon. A Heritage Moment on Canadian television brought his work on cerebral stimulation and discovery to the general public, you know, when the woman gets her brain pin-pricked (or something) and she says she can smell burnt toast. It's a dazzling story of total recall with the right stimulus but it's only occasionally true - in about 5% of cases. Still it's nice to think about, that all the time we put in is recorded somewhere - in our cerebral cortex or somewhere - and not lost, possibly recoverable. If you gave an event brain-time once, that is if it registered once, then it lies in wait for you at some future date. How much do you want to remember?

And then there's the theory of memory recovery through sensual stimulation, particularly through the olfactory sense. Apparently, a smell (aroma? fragrance?) can conjure up another time in one's life, more accurately and rapidly than any other stimulus. I used to keep an old lipstick because a sniff of it recalled one entire springtime of my life.

Well, it's interesting to note what triggers memory. One object, recalled in detail, can lead you on a path to the past, often with unexpected results, that is, more memories than you care to examine, or related events with causes you hadn't connected before, not always welcome.

Pick a year, any year, and try to remember what happened and what you learned. Give yourself a couple of chronological hints: the year you turned 33, for example, or 53 or 63, if applicable, and note what happened. Did you learn anything worth while, not earth-shattering, but useful?

Food for thought.