How does a nervous system produce behaviour? A case study in neurobiology.

The behaviour and nervous systems of most adult animals are extremely complex so to achieve analysis down to the cellular level we have studied a very simple animal, the hatchling clawed-toad tadpole. Even if the brain is removed these tadpoles can swim when touched showing that this behaviour can be co-ordinated in the spinal cord. The use of neuroanatomical and electrophysiological techniques to discover what nerve cells are present in the spinal cord is described and how they interact to generate swimming behaviour is explored. We now have a working hypothesis for spinal cord network operation which is being tested using computer simulations and which suggests general principles on how nervous systems may work. Our study also provides a bird's-eye view of current approaches to investigating nervous systems at the cellular level.