Update Rates

Modern data acquisition systems that are used for gathering data during testing are now digital instead of analog. In layman's terms, snapshots of data are recorded at a specified rate and then lines are drawn between the snapshots. In the case of a pressure reading, an acquisition system records a pressure of say 100 psig and then records the pressure again some specified time later. A representative graph is then produced by connecting these readings with straight lines. In modern systems this rate can be very high, up to 50,000 times per second (50,000 hz). Naturally, matching sampling rate with signal rate becomes pretty important as you can get graphs that have no resemblance to reality if you don't correlate them correctly. Old movies wherein the wagon wheels appear to be spinning backwards are a good example of this error. The camera took a snapshot at a time rate that wasn't correlated and when these snapshots are spliced together the wheel appears to be spinning backwards. It turns out our mind does the same thing with optical data that we take in with our sense of sight.

I was reading a short article about update rates and the how that correlates to our understanding of time passing. According to the article humans have the ability to do optical updates in the 60 hz range. In other words, we can't do it much faster than that no matter what we do. Dogs and cats are in the 80-90 hz range. The author was putting forth the suggestion that this has to do with life expectancy AND suggesting that updating at a faster rate in effect makes the total time passage between life and death similar in both instances. Carrying this comparison a little further he went on to explain that the common fly has the ability to update in the 225-250 hz range. (This kind of explains why it is so hard to kill a fly with a fly swatter as we must move in extreme slow motion from their perspective). They also live a very short life... but .... is it true that it seems just as long to them?

Of course my mind instantly went off in several other directions on that same subject. I read some time ago that we seldom actually update at full speed. It simply takes up too much concentration and energy and for efficiency we usually observe something for long enough to establish a pattern and then slow down our update rates in favor of predictive snapshots taken occasionally only to confirm the pattern is correct. Presumably.... this means that the more comfortable we get with the idea that we don't need to fully utilize full update rates the slower this actually gets until it is at a rate that is only a very small energy drain. We can recalibrate and update faster when something is amiss and we sense that our prediction is wrong. This was all written in explanation of optical illusions and the fact that eyewitness accounts are often so wrong when it comes to the actual physics of what happened.

I found this interesting enough at the time but somehow the correlation between update rates and our understanding of the passage of time also triggered some completely new thoughts. I have been researching how aging affects the brain as I have noticed that I sometimes now struggle to recall words or terminology for a short period while discussing things with other people. What I discovered is that the brain is a lot like a processor in that it is very parallel but not necessarily extremely fast. As we age we start to form more connections but are not as parallel. In other words, we can pull up more detail and in depth understanding but not necessarily at the same speed. It is the difference between passing information at top speed and passing information at a slower speed but with more contingent connections. Upon reading this, I felt a little better as I noticed in my own case that the terminology came to me; it just sometimes was not instantaneous. It more or less matches what I have read about how this works.

All of this goes to explain my next connection from the update rate. One of the things I discovered in researching how the brain works is the oft quoted idea that exercising the brain is a necessary part of staying mentally sharp. I think that is pretty well known and accepted but the update thing suddenly added another dimension to the equation. Currently, there is a sort of cottage industry of sites such as luminosity pushing mental exercise word games and such as a means of keeping the brain agile and healthy. I think this will only work to a point. If we do crossword puzzles or any other similar activity we find that they get easier the more of them you do. We are so good at pattern recognition type thinking that we begin to see who people who design such things go about the process. I found this out years ago when I started doing crossword puzzles in our local morning paper. I struggled at first but soon could do them in a very short time period. However.... I found that when I tried to expand and do those in the evening paper or other publications I was not nearly as efficient at getting them done. I didn't put a whole lot of thought into why but I think it was simply pattern recognition of that particular author.

It seemed an arcane and ridiculous thing to spend a lot of time on at the time and I soon lost interest. Keeping in mind the update rate thing it suddenly dawned on me today that it isn't doing anything in particular that keeps our brain agile it is doing something we don't know how to do. In other words, it is the very process of learning something new that requires our concentration.... our focus... to the point that we are in effect straining the bounds of that update rate and making our brain work at full speed or full effort. That is the key I think. A new subject...... one that we have to constantly go back and forth to different sources and really rack our concentration out on is tiring but absolutely necessary for high brain function. In effect, it is the difference between jogging around the block and doing interval training. It is the heavy lifting of wading through something complicated enough to require our full attention that strengthens the thought process; not the comfortable recollection and repetition of something we know well.

If this is true.... and I think it demonstrably is; maybe it also explains why people are often more comfortable in shared belief systems. Having faith in why things occur is obviously much less taxing on the brain than searching for reasons why things occur. It also explains why most people prefer affirmation to information. Maybe I should start a research project correlating intellectual curiousity with early onset dementia and Alzheimer's.

What does all this mean? Maybe it means I have too much time on my hands... but more likely it is just another manifestation of somehow needing to understand how everything ties together.