Why time appears to speed up with age

Not sure but according to Von Bertalanffy, brain "frequency" tends to slow down with age anyway. The same amount of perceptive events are spread onto longer periods of time thus appearing speeding up.

Cortical layers tend to be more of a way of dividing a specific low-level task up into sub-functions of information processing. For example, they do different networking/interconnect jobs in different layers and as one would expect different areas of the neocortex have varying layer counts (ranging from 1 to 6).

A more comprehensive computational unit of the cortex is actually the neocortical column which is a "horizontal" patch of neocortex. This is a functional unit that is probably very close to a microprocessor in analogy in that it contains a set of variables, some processing rules, input and output wires, and the capability of executing functions. A whole patch of cortical columns forms a sort of processing center, and interestingly enough, those tend to be specialized for certain kinds of information processing tasks. That's why in an fMRI scan whole areas of the cortex tend to light up together, and it's often the same areas geographically even if you scan a lot of people.

So if we're talking about a theory of localized neocortical involvement, my first impulse would be to check out those specialized areas for (non-)activity - something that led to pretty good empirical results before in related studies - as opposed to using the layers for that hypothesis.

my own subjective data:

in my childhood, a day seems to go pretty slow, probably because of just "messing around" tends to get boring. However I never felt the years as passing at a different rate than they do now (in my mid 30's).

I'm the type of person who "looks to the future" however so maybe if I was past-oriented I'd feel different.

My father always says life is like a roll of toilet paper. The further you get on the roll the faster it spins and the less of it you have left the more you cherish it.

Time is clearly a solid and measurable component of our physical world but our perception of it is warped by our own personal experience.

My wife can sit next to me for 8 hours and futz around the house etc while I sit with my headphones on and code 'in the zone'. I come out of the zone feeling as if I had just experienced only maybe an hour of zone time and she will laugh and point out the window at the dark night. :-)

I have six children, a daughter-in-law, a grandson and two cats. My life is clearly not moving any faster then my children but I do keep reminding them that as they get older they keep making me older!

I would argue that actually life goes slower the older you get. You have more context against the rest of your life and the OP might be using that as the reason we perceive life going quicker. But to me it's more like the "weight" of my life to date allows me a lot more perspective, I often measure an event against the birth of a child, a marriage, a house I used to live in etc. Less about the MM/DD/YYYY and more about the "Around this event this happened".

When time seems to have moved quickly is when you're talking to your mom and dad about your grandson and the day your baby girl was born and how they're going through all the same things you did when you were having children. It's the reference points that stun you. That somehow 25 years just vanished in a flash of light. But the reality is this is the same as this group talking about TRS-80 Model I's with 4k of memory. A lot has happened since then even though it was sort of like yesterday for those of us who lived through 300 baud modems and 16k memory upgrades.

This is why I love HN. The comments are better than the article.