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>>that they could notice a 1.5cm indentation difference - and not at eye level! Yes, their trained eye can most likely see far more than any of us. One thing
by toss1 4y ago
>>that they could notice a 1.5cm indentation difference - and not at eye level!
Yes, their trained eye can most likely see far more than any of us.
One thing I learned in neuroscience courses about perception is that one of the measures they take is the lower bound sensitivity of the perceptual system. One of the units is the JND = Just Noticeable Difference, which is well self-descriptive; find the smallest difference between two things that can be noticed. E.g., what is the smallest difference in pressure that is noticeable on a fingertip, tone or volume difference between two sounds, or the smallest size difference noticeable between two objects, etc.?
It turns out that top experts in any skill can have a JND that is about 10x finer than the average person. Moreover, they can not even know it!
I weirdly experienced this myself when I was one of the subjects in a test of discrimination of light brightness levels on a field with subtle differences. As they turned down the brightness in each round (and randomly moved the darker/lighter zones), the dark/light areas were completely obvious to me when everyone else swore that it was absolutely flat/even. I could only chalk it up to a decade of alpine ski racing training that had gotten me to top international racing levels — much of it was racing/training in flat light of cloudy days in snowfields — where we need to discern at high speed even the subtlest variations in shades of white to get critical information about snow conditions or contours. Until that test, I literally had no idea that anything was exceptional about my perceptual ability in this regard (my experience was generally that I wanted to see better), but training obviously drove changes down to the level of tuning the nervous system, even without specific intent to do so.
Science is so cool, and so are those Bedouin trackers!
- BLKNSLVR 4y agoThis is an interesting addition to my not-very-well stocked store of information about how tunable a human being is to specific tasks or situations. The second half of Neal Stephenson's Seveneves focuses on physical attributes, but I think it's the internal stuff like this that would be the real evolution paths.
- giardini 4y agoThe human eye can detect a single photon. Our other senses aren't so exquisite (it might be interesting to have the "nose of a dog" for awhile, say). But I am so often surprised at what I see.
- BLKNSLVR 4y agoI can't remember where I read it (probably a link from HN), about someone who, for a limited amount of time, had their sense of smell relatively suddenly become incredibly boosted, and my recollection is that they likened it to being a dog - the amount of information available to them about people in a Doctor's waiting room was surprising and confronting.
- toss1 4y agoWow, that's probably amazing! I once had an experience that gave me just a hit of what it must be like for cats and dogs. My cat had been hit by a skunk, and of course it was after hours in a rural area so it was the next day before we could get the tomato juice to clean him off. While he was still stinky, he mostly hid under a blanket with just his nose sticking out so he could minimize the smell. But he came out to go to his food/water bowl while I was reading a newspaper in a big chair (pre-internet times). So I couldn't see him and he was walking silently, but the smell was so strong that I could sense his location in full 3D — it was just a wonderous AHA! moment — "so THIS is what it's like for them - they can literally sense in 3D using smell the way we do with sight and hearing...". I know it was just a hint, as this was just the gains cranked way up on one smell, whereas they get the full-spectrum richness for everything, but, wow, what a revelation! The person's experience must have been truly mind-blowing!