Researchers at Hiroshima University have discovered how to turn off fear in goldfish using lidocaine, a common anesthetic. The researchers first conditioned goldfish to be afraid of light flashed in their eyes. Then, according to Ars Technica, the researchers:
. . .were able to show that, after an injection of a small amount of lidocane [sic] directly into the corpus cerebelli, the fish were unable to learn to be afraid. That is, once the lidocaine took effect, the conditioning of the fish to associate the flash and electric shock no longer took. Future flashes didn't slow the heart rate although, once the lidocaine wore off, the fish were still able to learn to be scared of the conditioned trigger.
The research team's findings have been published (.pdf) in the journal Behavioral and Brain Functions.
Photo by bensonkua
