Rhythm Generation in Young Xenopus Tadpoles
Behavior of just-hatched frog tadpoles and the neuronal networks underlying it.
Just after they hatch from the egg, tadpoles of the frog Xenopus can swim when touched and make stronger struggling movements when held. They provide one of the simplest organisms where the networks’ underlying behavior can be studied. Models of swimming networks rely on the interaction of pacemaker and network rhythm generation based on reciprocal inhibition and rebound. The network can be reconfigured during continuous stimulation when some neurons active during swimming become silent and new neurons are recruited, so the network generates the slower struggling pattern.
The spinal cord of the adult mammal has proved very difficult to investigate and understand. This is the reason to look for simpler, related systems which might be more accessible. The hatchling frog tadpole is a vertebrate like us, but its nervous system has only just begun to generate...
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