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Have you ever wondered why life seems to pass more quickly as you get older? (Hey, old-timers, I'm talking about us!) Each year seems to go by faster and faster ("Didn't I just do the taxes a few months ago?!?"). You remember in vivid detail your Christmases, but now they rush by year after year without making much of an impression. What's going on?

I just finished reading two very interesting books on time perception. The first is the aptly titled, Why Life Speeds Up As You Get Older: How Memory Shapes our Past by Douwe Draaisma. The other is Philip Zimbardo's and John Boyd's The Time Paradox. The first deals with the topic of this post, the second discusses ways to use time to your advantage—a topic for a future post.

I'm not a cognitive psychologist (so cognitive bloggers, feel free to chime in), but the best answer for this phenomenon is that the early years are full of first-time events—your first date, the birth of your first child, that first big vacation, etc. First occasions are novel events and we tend to make more detailed and lasting memories of those first times. When we repeat the event, year after year, it is less likely to make a unique or lasting impression.

This doesn't just happen with life events. We can observe the same phenomenon in a shorter space of time. For instance, the first couple of days of your two-week vacation seem long and leisurely, and the time goes slowly. You're that you have two long weeks of this. But, the next thing you know, it's almost over and you are heading home!

That new romance? Seems like an eternity between those early telephone calls, but before you know it, it's your 20th anniversary.

I noticed that my first academic job seemed like a long one. Everything was new, and I have many memories, and I often recall the many lessons I learned from that job. Interestingly, the position was only nine months long! The same is true of subsequent jobs: The first years go slowly and seem full of important accomplishments, then the next many years rush by in a blur.

So here is the key to slowing down the pace of life (at least psychologically): As much as possible, take advantage of new and unique experiences. When we go to the same places and do the same things, we don't make distinct memories and time seems to fly by. Zimbardo and Boyd suggest focusing on positive (rather than negative) past memories, trying to live more in the present, and holding a positive perception of the future—envisioning a future full of hope and . In other words, use time wisely.

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