Illustration: Mike Pick
Life is tough if you’re a fruit fly. You live for maybe two months, and you’re a great model organism for all sorts of experiments. You’ve got a limited set of genes so it’s pretty easy to get you to grow legs where your antennae should be, or grow nothing where your eyes should be. You’re expected to reproduce prodigiously, but sometimes you’re tricked into mating with a corpse.
And every once in a while, scientists reprogram your brain with a laser. An Oxford University team, led by Gero Miesenböck, did just this, taking fruit fly behavioral studies a step further by directly inducing a “memory” in a fly’s neurons.
Fruit fly brains, like their genomes, are pretty simple. Compared to human brains, which have as many as 100 billion neurons, the average fruit fly has something on the order of 100,000. A group of only 12 neurons is responsible for dopamine production, which is in turn responsible for the behavioral pattern in which the scientists in the Oxford study were interested: pain avoidance.
Instead of conditioning a fly to avoid a particular odor with electric shocks; Miesenböck and company replicated the neuronal change such conditioning would produce using a laser. Sure enough, the test subjects avoided the odor as if they had a memory of being shocked.
It isn’t clear whether this process really produces a “memory,” but neither is it clear what a fly memory is like on a phenomenological level. For that, you’ll have to shift focus from neuroscience to philosophy.
Mice for mice
As test subjects, lab mice have it a little better. Sure, you and all your mice friends are essentially clones, and you also have to put up with the occasional electric shock. But you get all the red wine you can drink, a chance to try out NASA’s levitation machine, and now you can play videogames all day.
Thanks to a nifty bit of virtual reality engineering, Princeton scientists were able to better study the part of the brain where location information is stored while a mouse ran in a digital maze based on the game Quake.
As in the fruit fly study, these Princeton scientists were zeroing in on the neurons associated with specific behavior, but in this case they were after the brain’s “place cells.” So named because they fire when presented with navigational landmarks that help place the mouse in space, these cells are studied using implanted electrodes. This presents a challenge to experiment design, as subjects need to be able to move around to put their navigational systems to the test.
The Princeton solution? Put the mouse on a mouse, or rather, a modified trackball that allows it to run in place in multiple directions. And instead of VR goggles, a virtual environment was projected onto a wraparound screen.
Judging by the video, the mouse is having a grand time playing with its new immersive gaming rig. Who wouldn’t? Similar tech is available to humans, but it will run you about $20,000, even with a $10,000 introductory discount.
As former champion Quake player, I’ve asked Seed’s own Lee Billings to endorse Princeton’s mouse; it wouldn’t be his first mouse endorsement. In any case, he should jump on this thing before Apple does. Just be sure to tell these mice not to stay up all night playing videogames; continuous exposure to light is bad for their brains.
Superfreaky now
Hotshot economist/journalist duo Steven Levitt and Stephen Dubner may have left their brains at home when putting together a chapter in Superfreakonomics, the follow-up to their 2007 blockbuster.
At the center of ongoing blogospheric firestorm is their chapter on global warming, or rather, global cooling. That the phrase “global cooling” made the cover of the book was the first tip that their coverage might be more about provocation than elucidation, and the corresponding chapter is indeed rife with myths, misquotes, and mischaracterizations. Instead of detailing them here, please consult this directory of debunkers: Joe Romm, Eric Pooley, William Connolley, Tim Lambert, The Union of Concerned Scientists, Nate Silver, and Levitt’s fellow New York Times blogging economist Paul Krugman.
Levitt and Dubner’s errors are not primarily on whether global warming is real, but on what causes it and how best to fight it. Nevertheless, the offending chapter muddies the waters at a time when clarity is desperately needed. A new poll by the Pew Research Center shows that Americans’ belief that there is a scientific evidence of global warming is at a three-year low: Only 57 percent think climate change is real, compared to 77 percent in 2006.
Hype is great for selling books and TV shows, but it has a way of coming back to bite you. It’s hard to believe it’s only been a week since the country sent its love up into the skies of Colorado for the now-infamous “Balloon Boy.” It turned out that the entire affair was part of a hype machine for a reality-TV show ostensibly modeled after “Mythbusters.” (Though it was unclear what exactly would be busted, considering Richard Heene’s history as all-around pseudoscience crackpot.)
Unfortunately, even real scientists are guilty of hype from time to time. It’s taken a few months, but the story of the “missing link” Darwinius—aka Ida—has finally come totally unraveled. It turns out that Ida is nobody’s ancestor, after all. Brian Switek, Scienceblog’s Laelaps, breaks down what this means for confusing the public’s understanding of evolution at the Times and BBC 4 Radio. In the end, it’s just more ammunition for the crazy people Richard Dawkins has to debate into the ground.
Each week, Seed’s Evan Lerner offers his take on the events and issues that shape science, science policy, and science journalism. Read previous Weeks in Review here, or follow him on Twitter.
Originally published October 23, 2009
