Good Pain???
A study at the Massachusetts General Hospital has shown that areas within the reward circuitry of the brain respond to
pain. By imaging the brains of 8 volunteers with a functional MRI as their hands were stimulated by warm or hot temperatures, the researchers were able to pinpoint the areas of the brain that responded. It turns out that reward-associated areas responded initially to the pain caused by the hot stimulus, but in a manner that was the opposite of normally observed reward based activity. Areas known to be associated with the pain response became active later.
Lobster noses
If you've ever wanted to understand the mechanics of just how
lobsters smell, researchers at UC Berkeley have figured it out. Lobsters smell by flicking their antennae through the water in order to bring the sensory hairs on them into contact with odor molecules present in the water. The scientists observed several hours of video tape to determine the speed, distance, and frequency of flicks. Once measurements had been made, they were able to make a model lobster (named the Rasta Lobsta) from an empty lobster shell, epoxy, and a small motor to move the antennae. They then ran the lobsta through a virtual environment, in which fluorescent dye was substituted for odor molecules so that events could be visualized. This done, they determined that in order to get "odor" molecules to stick to the feathery antennae a lobster has to flick its antennae forward quickly. The backstroke is slower and traps the molecules in the sensory hairs. Then the next forward flick brings in a new population of molecules to be smelled.
current science news posted by Kirsten at 12/21/2001 03:04:00 PM
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