My research interests focus at the intersection between the study of how a nervous system is assembled during embryonic development and how activity in the nervous system allows an animal to produce behavior appropriate to its circumstances. I study these questions in an annelid worm--the medicinal leech, Hirudo medicinalis--because it has a relatively simple nervous system, yet it produces complex behaviors. In addition, leech embryos are quite robust, allowing us to do a variety of experiments.

Two active projects in the lab are:

(1) a detailed study at the cellular and molecular level of how specific synaptic connections are formed to produce a behavior called local bending. We expect to learn general mechanisms that produce specificity in the synaptic connectiions within neuronal circuits.

(2) a study of how two components from the venom of an annelid worm-hunting marine snail, Conus imperialis, change activity within the central nervous system of an adult leech and thus modify the behavior that the animal produces. By exploring the cellular effects of these two toxins, we expect to learn more about how previously described behavioral circuits in the leech operate.

                     Here's a leech at about 45% of the way through embryonic development

Here are some recent publications to introduce you to my work:

Marin-Burgin, A., F.J. Eisenhart, S.M. Baca, W.B. Kristan, Jr., and K.A. French Sequential development of electrical and chemical synaptic connections generates a specific behavioral circuit in the leech. J. Neurosci., 25:2478-2489. (2005)

French, K.A., J. Chang, S.Reynolds, R. Gonzalez, W.B. Kristan, III, and W.B. Kristan, Jr. Development of swimming in the medicinal leech, the gradual acquisition of a behavior.J. Comp. Physiol. 191:813-821 (2005).

Fan, R-J, A. Marin-Burgin, K.A. French, and W.O. Friesen.A dye mixture (Neurobiotin and Alexa 488) reveals extensive dye-coupling among neurons in leeches; physiology confirms the connections. J. Comp. Physiol., 191: 1157-1171 (2005)

Marin-Burgin, A., F.J. Eisenhart, W.B. Kristan, Jr., and K.A. French. Embryonic electrical connections appear to prefigure a behavioral circuit in the leech.J. Comp. Physiol 192:123-133 (2006).

Cornford, A., W.B. Kristan, III, S. Malnove, W.B. Kristan, Jr., and K.A. French. Functions of the subesophageal ganglion in the medicinal leech revealed by ablation of neuromeres in  embryos.  J. Exp. Biol., in press (2006).