Strange Loops

“Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute. THAT’S relativity.” –attributed to Albert Einstein

Our subjective experience of how fast time is passing depends on the situation we are in. Waiting for a pot to boil while you watch it can feel like a frustratingly long time, and watching a clock as it ticks down the last minutes of a long meeting or class can be excruciating. (In fact, studies consistently show that we perceive a watched clock to slow down or stop briefly when we first look at it, an effect known as chronostasis).

On the other hand, when immersed in enjoyable activities, we often lose track of time and are surprised to find out just how much time has really passed while we were so engaged. Time flies when you’re having fun, as the expression goes.
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When you think of intelligent non-human animals, you probably think of apes: they use tools, appear to have culture, can be taught language-like communication systems, and the list of uniquely human traits seems to be ever-shrinking thanks to them. Maybe you include dolphins in your list of smart animals.

When asked to imagine intelligence in the animal kingdom, it’s unlikely that the critters coming to mind would be octopuses, fish, birds or insects. But as a recent Scientific American article on comparative cognition points out, some branches of the tree of life that don’t normally get a lot of attention for their smarts have actually demonstrated some pretty impressive abilities.

In the sea, cephalopods (octopuses, squid, cuttlefish) are the mental badasses of the invertebrates. Octopuses, for example, are not only great problem solvers, but can learn to solve a problem simply from watching other octopuses do a task. Fish may be smarter than we give them credit for. Goldfish, for example, can orient their way through mazes (more efficiently than slime-mold, even). So can reptiles like turtles.
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Do you remember where you were when you first saw the closed-circuit TV footage of the 7/7 London bombings in 2005?

Hopefully not, else you may be imagining things — no such footage exists. But if you claimed to remember it, you would be in good company. Around 40% of British college students said they remembered such a video, when filling out questionnaires a mere three months after the bombings. It seems as if people had invented a memory to fill in or coalesce the details of an event they had seen or heard described later.

Psychology professor Elizabeth Loftus has studied false memories like these for a while. For example, one study she worked on showed participants a Disneyland ad with Bugs Bunny in it. Almost a third of people who had been to Disneyland at some point in their life falsely reported that they had met Bugs Bunny and shook his hand there — falsely because Bugs Bunny is a Warner Brothers character. The false memory was much less likely in people who were shown the same Disneyland ad without Bugs Bunny in it.

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Normally our bodies receive sensory input through eyes, ears, skin and other systems, and those inputs synch up in consistent ways, such that our brain can put it together into a coherent picture of the 3D world around and including us. My visual input is basically just a sterooscopic movie, but because it matches so well with tactile and other input (you feel the toe-pain of a rock right when you see that familiar foot object hit it), we interpret those images as us being inside a 3D world. Really we construct the world around us — and we presume our construction is veridical because it consistently predicts the matching up of sensory events (occasional illusions notwithstanding).

This makes perfect sense if, as we assume, we are bodies inhabiting a 3D world — bodies including brain systems that integrate sensory input from different feedback devices (including inner feedback from proprioception and the like). But if this is the case, then we should theoretically be able to disrupt or alter the brain processes that synch up our various sensory experiences, such that our consistent, 3D view of the world from our own body’s perspective is thrown out of whack. But what would happen, in that case?

We’re all familiar with claims of out-of-body experience such as, say, looking down on your own body from above. That is to say, some people report visual input that seems to locate itself in a spatial location within the 3D world that is not the same as usual. In fact, they may see an image of their own body, much like what we see in a mirror; except in the case of a mirror the various sensory modalities still match up. When seeing yourself in a mirror, the proprioceptive and muscular feedback of lifting your arms corresponds to visual feedback of the arms moving up in the mirror image, as well as peripherally seeing the arms come up as normal. In an out-of-body experience, however, the body could move (or not) in a way that doesn’t correspond to the changes in sensory (usually visual) input to the experiencer.
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“So what is this mind of ours: what are these atoms with consciousness? Last week’s potatoes! They now can remember what was going on in my mind a year ago — a mind which has long ago been replaced. To note that the thing I call my individuality is only a pattern or dance, that is what it means when one discovers how long it takes for the atoms of my brain to be replaced by other atoms. The atoms come into my brain, dance a dance, and then go out — there are always new atoms, but always doing the same dance, remembering what the dance was yesterday.”
–Richard Feynman (The Value of Science)

Back in 1953, researchers at the Smithsonian Institution concluded from radio isotope tracings of chemicals entering and leaving the body that we replace around 98% of our bodies’ atoms every year or so.

Most of us are familiar with the cells in our body being replaced (the new daughter cells being made up largely of new food we take in). Skin cells slough off constantly and yet we retain skin. Hair is lopped off and new hair comes out. The stomach lining is replaced in a matter of days, the liver in weeks. An 18% yearly calcium replacement in the adult body replaces most of our bones in a few years. Neurons essentially stay for life (though adult neurogenesis sometimes replaces these).

But even those cells that are not replaced through duplication — even those holdout cells like neurons — have shifting make-up on the level of particles. New atoms flow in to replace old ones.

Now, we need not concern ourselves with whether or not every single atom actually gets replaced, or on what timeframe. We can at least be confident that a very large and significant amount of material in our bodies — even in our brains — was not there previously and won’t be there for very long. As Feynman put it, our bodies and brains are last week’s potatoes.

Obviously, this suggests that the individual atoms in our brains aren’t like packets of information holding memories or personality. Rather, the structure is what is important to cognition: whatever materials can instantiate that structure so as to carry out the computations and lead to the proper outputs are sufficient.
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At the Primate Research Institute in Japan, Ai is a chimpanzee in her thirties who has been involved in cognition research for decades. She’s well-known for learning to use our familiar numerals (1, 2, 3…) to appropriately label sets of objects (5 bananas, etc.), and she’s done some other really cool things with numerals and numbers.

What I didn’t know until recently is that she has a son, Ayumu, and he too is becoming quite the research superstar. A recent study demonstrated his talent for remembering an array of randomly mixed numerals on a computer screen, after they were very briefly flashed to him and then masked by white boxes. He had to touch each of the hidden numerals in order without a single mistake in order for a trial to be considered a success. This seems to show a pretty impressive working memory for visuo-spatial layouts, but does that mean Ayumu has something like eidetic memory (”photographic memory”)?

I don’t have the full article. However, previous studies with other chimps (including Biro and Matsuzawa’s 1999 study with his mother Ai) have shown that they “queue up” action sequences in a task like this, such that if the targets change/move in the middle of a trial, their fingers still briefly travel toward where the right answer would have been. Perhaps this is a demonstration of a pre-planned motor sequence, rather than anything like photographic memory.

One way to test this might be to remove one or more of the number locations completely (including the white box masking where it originally was flashed). If the chimp has a photograph-like visual of the layout in memory, then he should be able to continue the sequence by skipping over the missing numeral. But if he has pre-planned his actions in advance (as mother Ai did for a set of 3, 4 or 5 numerals), then his finger should still move to where the missing numeral disappeared.

Either way, if the task sounds easy, try it for yourself. (even with only 5 numerals, it’s pretty tough at first). The study compared college students’ performance to that of Ayumu, and the chimp won. Note that without access to the paper, it’s hard to know if the setup was truly the same. Ayumu almost certainly had a lot more practice than the college students (but then this is necessary to teach him what the task is, whereas humans can have instructions explained to them). Also, Ayumu’s numerals aren’t masked until he touches the first one (usually very quickly), but the college students’ might have been masked immediately after flashing (as the website demo with fewer numerals does).

At any rate, the experiment is a very impressive demonstration of a larger memory span than has been seen before in a setup like this. However that information is stored, it’s cool that he can do it.

[Thanks to Primatology.net for the game link]