Why Can’t We Walk Straight?

Interesting insights into why we need to dream. Get good sleep!

Who better to review Chess Metaphors: Artificial Intelligence and the Human Mind than Garry Kasparov? I found his thoughts on human/computer “partnership” matches particularly fascinating.

So cool, the how and the why of controlling neurons with light. First, the why. Current methods lack precision:

Drugs and implanted electrodes can influence the brain, but they are terribly imprecise: Drugs flood the brain and affect many types of neurons indiscriminately. Electrodes activate every neuron around them.

This is bad for researchers, because practically every square millimeter of the brain contains a mess of different kinds of neurons, each specialized for a particular task. Drugs and electricity set off cascades of unwanted neural activity. Side effects.

It’s bad for patients, too. Cochlear implants, which let the deaf hear by shocking the auditory nerves, produce fuzzy sound because the electricity spreads beyond the neurons it’s aimed at. Deep brain stimulators for Parkinson’s patients allow them to walk and speak but may cause seizures and muscle weakness. Electroshock can help depression but often results in memory loss.

But if you can shine a light on just the section of the brain you want to fire (or not fire) you can get great precision. Of course, neurons are not light sensitive. At all. The solution? Insert genes from plants, which ARE light sensitive, into the neurons. How to do that is yet another cool thing, as is the potential Parkinson’s treatment, but I’ll leave that for the article.

Unfortunately the recent profile of V. S. Ramachandran in The New Yorker is subscriber-only, but you can still find out what’s going in this picture here:

Related, don’t miss this Atul Gawande piece (I think I’ve linked this one up before).

I really have to try the ping-pong ball-induced hallucinations.

Jill Price remembers everything. There is a downside:

In addition to good memories, every angry word, every mistake, every disappointment, every shock and every moment of pain goes unforgotten. Time heals no wounds for Price. “I don’t look back at the past with any distance. It’s more like experiencing everything over and over again, and those memories trigger exactly the same emotions in me. It’s like an endless, chaotic film that can completely overpower me. And there’s no stop button.”

She’s constantly bombarded with fragments of memories, exposed to an automatic and uncontrollable process that behaves like an infinite loop in a computer. Sometimes there are external triggers, like a certain smell, song or word. But often her memories return by themselves. Beautiful, horrific, important or banal scenes rush across her wildly chaotic “internal monitor,” sometimes displacing the present. “All of this is incredibly exhausting,” says Price.

I’ll try to remember this next time I am cursing myself for losing my car keys.

From The Olfactory Lives of Primates by Robert M. Sapolsky (Virginia Quarterly Review, not online):

For sensory systems, how many steps does it take to get from the eye, ear, or path of skin to that emotional limbic system. Roughly ten steps. Take vision. First there's a layer of neurons in the cortex that breaks the visual scene into dots, then a next layer turning the dots into lines, then collections of lines, on and on. Finally, an Ice Age later, by a neuron's temporal standard, visual information trickles to the limbic system, and you activate an emotional response appropriate to seeing the face of someone intent on, say, seducing you or ethnically cleansing you. All of the sensory systems, that is, except olfaction. How many steps from smelling something to the limbic system? Just one.

See also: NY Times article on smell.

Pretty interesting read over at Powering Muscles: 10 Ways to Train Your Brain for Better Performance:

The best evidence that muscle fatigue starts in the brain comes from studies involving sensors that measure electrical activity in the muscles. The amount of electrical activity in the muscles is a direct indicator of how hard the brain is driving them to perform work. In a recent French study, researchers found that an involuntary drop in performance during repeated bicycling sprints was accompanied by a comparable decline in electrical activity in the muscles. These results clearly showed that fatigue was not caused by acid buildup or any other factor within the muscles themselves. Instead, it was caused by reduced drive from the brain.

There is no spoon.

Bonus link: over at Salon a writer decided to give Charles Atlas' 1922 "Dynamic Tension" course a go. You know, the one you saw advertised in comic books as a kid? Pretty funny stuff. Not all crazy (but some very crazy).

Healthbolt on pumpkin seeds (and what your body does with all the tryptophan they pack):

...tryptophan works by morphing into seratonin, (which is known for fighting depression, reducing anxiety, and minimizing anger), making tryptophan pretty much the Wonder Amino Acid. In fact, in a recent study, folks who were asked to give a speech after eating a pumpkin seed bar had much lower heart rates and anxiety an hour later than those who didn't have the seeds.

Quick Googling turned up Dagoba's Seeds chocolate bar (68% cocoa, plus hemp, pumpkin and sunflower seeds). Mmm, something to indulge in come mid-July, after my second sentence is up.

I've wondered before (although perhaps not on this weblog, can't remember) how much of all medicine rests on the placebo effect. How many treatments would simply stop working if the placebo effect were suddenly erased from our minds? Consider this, from the article 13 Things That Do Not Make Sense:

Don't try this at home. Several times a day, for several days, you induce pain in someone. You control the pain with morphine until the final day of the experiment, when you replace the morphine with saline solution. Guess what? The saline takes the pain away.

This is the placebo effect: somehow, sometimes, a whole lot of nothing can be very powerful. Except it's not quite nothing. When Fabrizio Benedetti of the University of Turin in Italy carried out the above experiment, he added a final twist by adding naloxone, a drug that blocks the effects of morphine, to the saline. The shocking result? The pain-relieving power of saline solution disappeared.

Stop reading now if you don't want me to ruin certain treatments for you, because faith is everything...

Still here? Okay... I was discussing this with my neuromuscular therapist friend yesterday, and she mentioned a few interesting studies, one which showed that of the "alternative" pain management techniques, acupuncture appeared to be the most effective. However, another study showed that fake acupuncture (sticking in needles randomly?) is pretty much just as effective as real acupuncture. Did some Googling, found a bunch of references, but I particularly liked this one: Sham Acupuncture More Effective Than Sugar Pill in Easing Arm Pain.

First question that leaps to mind: what do you use as a control group if you're studying the placebo effect? :-)

After a few weeks of receiving the paper version of The New Yorker (rather than the limited online content) I can see why a buddy of mine found my not subscribing inexcusable. Fantastic. Each issue always has at least one must-read article in it, and often more than that. Off the newsstand you'd pay over $200 for a year's supply, but you get get it for less than $1/issue delivered. The highlights of the July 3rd issue were an interesting World Cup piece, a fascinating article on hemispherectomies (brain surgery, exactly what you'd guess it is from the word):

I asked him Mike's question, about all that space left by the missing lobes. In the past, [Dr. Ben Carson] said, doctors worried about this and tried to anchor the remaining brain by stitching it to the dura. They would put all kinds of things in the cranial cavity—one surgeon used sterile Ping-Pong balls. But, as Carson did more hemispherectomies, he realized that the brain's own drip of cerebrospinal fluid could adequately fill the cavity. Sometims the remaining brain moves during the weeks following the surgery, but usually by less than an inch. "It doesn't seem to be a problem," he said. Much of Carson's method is intuitive. "You develop a feel for the brain," he said. "Normal brain feels like a very soft boiled egg. A bad brain feels like a mushy apple."

... and a profile of David Addington (Cheney's chief-of-staff):

David Addington is a satisfactory lawyer, [Bruce] Fein said, but a less than satisfactory student of American history, which for a public servant of his influence, matters more. "If you read the Federalist Papers, you can see how rich in history they are," he said. "The Founders really understood the history of what people did with power, going back to Greek and Roman and Biblical times. Our political heritage is to be skeptical of executive power, because, in particular, there was skepticism of King George III. But Cheney and Addington are not students of history. If they were, they'd know that the Founding Fathers would be shocked by what they've done."

A bit off the beaten path for this blog, but fascinating enough to post. Mirror therapy:

[Complex regional pain syndrome] occurs in about one-third of people who fracture their wrists: they suffer unexplained persistent pain in their hand, arm or shoulder once the supportive plaster cast is removed. The pain can be so bad that some patients beg for their arm to be amputated, says Candy McCabe, who developed the novel mirror therapy at the University of Bath in the UK.

In the study, eight CRPS patients sat in front long mirrors. These were placed so that each person could see only the healthy half of their body, along with another reflection of the same half.

The result was that the side of the body with the painful arm was hidden from their view and it appeared to the patients as if they had two healthy arms. They were told to concentrate hard on the image and try to believe that what they saw was a true depiction of themselves.

"Three of them were cured instantly; the others took a little longer," says McCabe. "But once the mirror was removed, the pain returned." However, with continued mirror therapy, six people were completely cured. The two exceptions had conditions complicated by limb ulcers and actual physical distortions.

Be sure to click through to find out what happens to healthy folks subjected to the treatment.