Zombie Fish

I usually don't go in for "News of the Weird" types of things but this one is not only weird, it also has a fascinating explanation.



Zombie fish flapping explained thanks to "KickinPhresh" at Reddit:

The flopping action is actually the stimulation of local central pattern generators. A central pattern generator is a neural circuit which generates oscillatory patterns. Walking, respiration, slithering, and swimming (in the case of fish) are all driven by central pattern generators.

The general scheme of a central pattern generator is left/right and extensor/flexor antagonism. When any muscle moves, the opposing muscle will be simultaneously inhibited by an interneuron to allow for efficiency, and this motion will be 180 degrees out of phase with the contra-lateral side.

Fish have local central pattern generators up and down their side that coordinate this motion WITHOUT the brain. The pattern is generated locally, and only modulated and switched on/off by the brain. The motion seen in the video is due to the activation of central pattern generator circuits. The motion in the video is likely due to the activation of CPG circuits by high sodium (or the combination of salt, lemon and the aluminum foil.