AOI: Rat metacognition?

Rat metacognition?  I don't think so.

This article in Current Biology last year, Metacognition in the rat, argues that rats have similar 'metacognitive' capacities as other species that have, basically, bigger brains.

It doesn't matter if one thinks 'metacognition' (thinking about thinking) is a sign of self-awareness; basically, the result reported seems more easily explained by the rats learning an additional response option.

The type of experiment employed is an adaptation of one first used in animals (I think), where a forced-choice task is adapted to give a third "uncertain" response.  In this case, the rats were supposed to discriminate a tone duration, responding, say, to the left lever when the sound was short and the right lever when the sound was long.  Reward is given for correct responses.  Here, the rats also have an option to bail out from the forced-choice and make a response to a middle lever that gives a smaller but certain reward.  For hard trials, the rats learned to make the uncertain response.  The authors interpret this as evidence that the rats know what they know and don't know, that the rats are aware of their knowledge - when the rats are unsure of the answer, they opt out of the choice.

It seems much easier to interpret this result with a different explanation.  A simple learning mechanism can learn, based on feedback, that a perceived short tone = left, while a long tone = right.  The degree of activation of each response option could index the animal's certainty.  Given only two options, difficult trials are a tossup - but the internal state of the system in these cases would be a mixed activation of both left and right options (in the classic model of cognitive control, this conflict would be associated with activation of the anterior cingulate, anterior insula, etc).  Now, when given a third small certain reward response option, the optimal behavior is to learn to interpret the state of maximal conflict/uncertainty as a third state-response pair:  short=left, long=right, conflict=middle.  The degree of, say, anterior cingulate activation would basically represent the degree of activation of the middle option.  There is no need for metacognition at all, only a simple system that tracks uncertainty and response conflict, variables that may be required in any model capable of performing a forced-choice discrimination task, plus the ability to associate this internal system state with a response.

(hat tip from the Frontal Cortex)

exercise doesn't actually help depression

and now we know. All that advice about getting out and getting some exercise so you feel better is now not based on any real research. It seems that people do improve, but those people who get better

In the August issue of Archives of General Psychiatry:

Results Cross-sectional and longitudinal associations were small and were best explained by common genetic factors with opposite effects on exercise behavior and symptoms of anxiety and depression. In genetically identical twin pairs, the twin who exercised more did not display fewer anxious and depressive symptoms than the co-twin who exercised less. Longitudinal analyses showed that increases in exercise participation did not predict decreases in anxious and depressive symptoms.

Conclusion Regular exercise is associated with reduced anxious and depressive symptoms in the population at large, but the association is not because of causal effects of exercise.

Here's the press release. I'm sitting on the couch from now on.

why i'm not a "psychologist" #17

besides the issues with telling people you are a psychologist at parties, there is stuff published on theories like this:

http://improbable.com/2008/08/06/terror-management-theory-and-female-bombshells/

(more comment to come)

one possible thing before breakfast

Thought Experiment I

"Alice laughed: "There's no use trying," she said; "one can't believe impossible things."

"I daresay you haven't had much practice," said the Queen. "When I was younger, I always did it for half an hour a day. Why, sometimes I've believed as many as six impossible things before breakfast."

Charles Dodgson, Alice in Wonderland

I've already had breakfast, and this idea is a very possible thing, but thought experiments are very much in spirit of the beautiful Alice in Wonderland.

It's simple. Two points will help illuminate it. First, because special relativity abolished any idea of an absolute frame of reference in the universe, we have more than just imagined freedom to create our own maps of space - this freedom is, in a way, supported by physics*. Anything can be the stationary point in a defined frame of reference - the earth, which many people pick by default, or the sun, the Milky Way, Paris, Mecca, etc.

Second, consider that the information that reaches you at any point in time is limited by the light cone stretching around you in space and time, sortof like an unimaginably huge sphere, spreading outwards at the speed of light. As far as we know, nothing exists beyond your light cone, because by definition our observations are limited to this part of the universe. You are inescapably in the center.

With these two ideas, the freedom of frame of reference, and the centrality of your point of view granted simply by the speed of light revealing the observable universe, you can thus imagine that you are the stationary center of the universe. Put your brain in the center of everything, and try to imagine that it never moves, but everything else does. When you walk down the street, the Earth is spinning away under your feet, but your head remains still, in a location that hasn't changed, well, since you were an egg in the womb.

But you might wonder, if I'm walking down the street and I am not moving but my legs are moving the whole Earth, and slightly rotating the whole universe, wouldn't that be impossibly hard? It seems like it would be, however, it is the same problem, physically, to move your body with respect to the stationary frame of reference of the Earth as it is to move everything else with respect to the stationary frame of reference of your brain.

It's a bit of an odd way to look at things, but a rather illuminating perspective. An updated, and more fun, version of the the brain in a vat perspective. Your brain is the stationary center of the universe; things come into it, things happen inside it, things are done to the world. There is experienced light inside your head, but everywhere else is dark. The problem of planning is not how to move about the world, but how to move the world about you, how to bring new experiences and rewards to you. Think of those hand-held mechanical games where you are trying to navigate a little silver ball through a maze of obstacles into a hole by tilting the board - only think of the silver ball as completely stationary, with the maze world spinning by it until it falls home.

Sure, sure, this is sortof just amusing sophomoric philosophy, but simple changes in perspectives and reframing of problems like this can be extremely helpful in science.

One simple implication of this perspective is that everyone (and thing) can be seen as the center of the universe. Think what you will about ethical relativity; physical relativity is also lots of fun.

* this point taken from special relativity, of course, could change because of further developments in physics. I'm no expert on the preservation of relativity ideas in unified theories, but it seems like a good thing to preserve...

Listening to: John Luther Adams, In the White Silence

distractable chimps, aggressive antelopes

Brief news flash from the world of animal research:

Recently, researchers reported that chimpanzees are sometimes more patient in waiting for a reward than humans are. This is surprising, given that people have long thought that our "amazing" abilities to delay gratification were due to our evolution-granted bigger foreheads. But now*, it turns out that chimps employ some of the same strategies used by kids to get more cookies by waiting - they sit on their hands, or they play with toys. If you haven't seen the videos produced by Mischel's work on delay of gratification in kids (an ability that later predicts SAT scores), you're really missing out. BUT we're all missing out on the chimp story because the researchers didn't post any videos! (I think half the reason I follow primatology research is to watch chimps doing smart things)

Usually, in those old nature documentaries, you see the males fighting for weeks for the right to inseminate the choicest females. But no one has really seen a reversal of this dynamic. Turns out, this mate competition reversal is predicted to happen when the species is promisuous, there are a lot of females, and the guy tends to run out of sperm. Here the guys want to mate with all the females so they can spread their limited seed. But the ladies want the good guys all to themselves. So, what to they do? The African topi antelope women get persistent and aggressive. Getting too angry is a turnoff, though, as the guys counterattack or run away. The researchers made an understated note that these reversed "conflicts probably often go unnoticed because males, in contrast to females, can avoid mating without conspicuous resistance."

* Chimpanzees use self-distraction to cope with impulsivity. T.A. Evans and M.J. Beran, Biology Letters 3, 2007.
+ Reversed Sexual Conflict in a Promiscuous Antelope. J Bro-Jørgense. Current Biology, December 18, 2007.

a dialogue on determinism?

I'd like to find intelligent discussions of determinism, and discuss the issue myself. But I never find anything, and I always end up keeping to myself. Sure there are (psychological) reasons why important things are ignored. This is one hell of an elephant, though. An absurd one, but are you calling all of this normal?

- now I do recall how law is one of the few places that plays with this. They like to take teeny bites, as if just a wee bit won't hurt. As far as your legal theories go, guys, with that bite you've already lost the whole house.

something about pollock

A few months ago, I found myself staring at a Jackson Pollock painting at the Met. I've done it before and didn't get anything out of it. (Well, I was amused once when a National Gallery security guard pointed out the few bugs and cigarette butts entombed in one.) But that day I just stared. Stared like I love to do with bright modernist paintings, waiting for the afterimage to show me the most vivid opposing colors this side of drugged Van Gough viewing. Of course, Pollock doesn't have much for color.

Then layers of the painting started to shift and move. You can almost direct the movement if you keep your gaze focused. This happens naturally, I think, or anyway, I remember it happening to me as a kid staring at a big plywood board. Perhaps when the visual cortex gets a fixed input of a pattern for a long enough time, the brain invents movement?

Is this something that people see in his paintings? That they are alive, and alive like others cannot be because of the pattern? If not, maybe they should, and otherwise I'm still searching for what they're worth.

The press needs a science education

Dear Sir,

The LA Times recently published an Op-ed by Mr. Amen on brain disorders and behavior, arguing that current candidates for the presidency exhibit obviously dysfunctional brains and that they should have their heads examined.

What were you thinking? As a working cognitive neuroscientist, I don't have time to
rebut everything said in the article and Amen himself, so I'm just writing to help
editorial boards learn.

But see this Slate article for a great start.

Sure, it is an opinion page. But publishing opinions by quacks on scientific areas in
which the public is extraordinarily interested is an terrible disservice to your readers.
People love to learn about the brain, but do not understand that this man is not a
scientist! You've now joined the notorious company of the New York Times in publishing pseudoscience brain Op-eds in the past weeks (and I'm sure that both of these helped the writer's company coffers). Thank you, our nation's papers of record, for helping to educate the public about what real neuroscientists do. Next time, when considering one of these pieces, do researchers and the public a favor and just say no.

p.s. - please read the New York Times letter to the editor, signed by 17 cognitive neuroscientists (a number of which I have been lucky to work with), protesting last month's atrocious political brain scan "experiment" Op-ed.

People want to learn about the brain, so please, I beg you, stop hurting america.