I understand about time moving faster as you get older, but I get the feeling my general all-round perception of time is askew in many ways. For instance, I'll sometimes think about something that happened a year ago and it seems more recent than something which I remember from 6 months ago. 
 
But yeah, the years speeding up....it was a great shock to me how quickly the ages of 30-40 flew by. I'm 40 now but I can remember the last day of my 20's like it was yesterday...I distinctly remember sitting in the kitchen in my place on Nantucket (where I lived at the time), eating spaghetti & tomato sauce and reading "A Heartbreaking Work Of Staggering Genius" by Dave Eggers, and every now and then thinking "holy crap, I'm 30 tomorrow" before burying the thought and going back to my book. 
 
But the weird thing is that this memory seems fresher than certain things I can remember from 5 years ago. 

 
Nostalgia's a thing of the past.

sharke
I swear, the last few years my whole perception of time has gone completely off its rocker. Is this normal in your late 30's/early 40's? 

It isn't necessarily indicative of age. My wife has always referred to events in her life as having happened "a few years ago" and most of those events happened thirty or more years ago. Of course, when she first started saying that, they really were only "a few years ago."
 
So, no worries. You're fine....
 
But when you hit 50...! Hoo-boy.

Kalle Rantaaho
That's how I've always figured it is. That's why it puzzles me that I've never ever seen this explanation mentioned in any articles or discussions on perception of time. It's as if the scholars didn't take this point of view in consideration at all. As if it was too simple.

They may have missed it, but Einstein didn't. He said time is constantly speeding up, so it's not just perception based on how long we've been alive; years are going by faster for us than they did for our ancestors. And our great-great-(ad infinitum)-grandchildren might only be on the planet for the blink of an eye.

sharke
I'll sometimes think about something that happened a year ago and it seems more recent than something which I remember from 6 months ago. 

Something else to keep in mind from recent physics discoveries is that all time happens/happened/will happen simultaneously. You may simply be being lead around by a tachyon that's skipping backwards in time. Also, time and light are slowed and can even move backwards in time when acted upon by outside forces. So, when you're surrounded by light beams, there's a 50/50 chance you're traveling backwards in time or the world is or the light is and it's really screwing with... well... everything.
 
 

rontarrant
 
Something else to keep in mind from recent physics discoveries is that all time happens/happened/will happen simultaneously. 

 
It sounds like scientists came to that conclusion before they'd even finished their experiments. 
 

Time is an illusion.

sharke
A few years ago I saw Bert Jansch live in Brooklyn, great gig and whenever I think back to it now I always think it was about 4 years ago. Just found the ticket stub when cleaning out a cupboard tonight. 
 
It was in 2006. How in the hell did that happen? I swear, the last few years my whole perception of time has gone completely off its rocker. Is this normal in your late 30's/early 40's? 

Made me laugh reading that because me and the guy I work with have almost coined " it must have been about 4 years ago" as a catch phrase of late when recalling a past event, to the point where it has become a kind of in joke with us. It never is 4 years, it's always way more than that - in the last instance it was actually 10 years ago.

sharke
It sounds like scientists came to that conclusion before they'd even finished their experiments. 
 

Yeah, I think you got it now.

paulo

sharke
A few years ago I saw Bert Jansch live in Brooklyn, great gig and whenever I think back to it now I always think it was about 4 years ago. Just found the ticket stub when cleaning out a cupboard tonight. 
 
It was in 2006. How in the hell did that happen? I swear, the last few years my whole perception of time has gone completely off its rocker. Is this normal in your late 30's/early 40's? 

Made me laugh reading that because me and the guy I work with have almost coined " it must have been about 4 years ago" as a catch phrase of late when recalling a past event, to the point where it has become a kind of in joke with us. It never is 4 years, it's always way more than that - in the last instance it was actually 10 years ago.

I would not be surprised if they did a study and found that "4 years" was the average guess of people thinking of things which happened some time ago, but not too long ago.