The paddlefish, Polyodon spathula, is a filter feeding fish. Its main prey consists of small water fleas (e.g. daphnia). In the course of my investigations I studied the response properties of afferent fibers and dorsal octavolateral nucleus (DON) neurons to moving DC field of different polarity. Those fields mimick the electric field that surrounds living daphnia.

In addition I characterized the response properties of neurons in the lateral mesencephalic nucleus (LMN) to uniform electric fields, to moving artificial DC stimuli and to live daphnia. I compared those responses with the repsonses of neurons in the DON. In a separate study I investigated the different receptive field properties of units in all known electroreceptive areas of the paddlefish brain and tried to relate them to specific motor behaviors such as prey catching or object avoidance.

Paddlefish striking at an artificial dipole (picture courtesy of Lon Wilkens)