Hard copy can be borrowed from the University of Washington or b/w copies from University Microfilms. Below is the record from UW libraries. There is no truth to the rumor that every graduate student places a $20 bill in the pages of his dissertation as a reward to the first person to read it.

Author: Murray, James Alan, 1966-. Title: Neural correlates of orientation to water-flow in Tritonia diomedea / by James Alan Murray. Pub. Info.: 1994. Phy Descript: vii, 79 leaves : ill. (some col.) ; 29 cm. Notes: Thesis (Ph. D.)--University of Washington, 1994. Vita. Includes bibliographical references (leaves [76]-79). Depository copy has number: Thesis 42526. LC Subject: Tritonia-diomedia -- Behavior. Tritonia-diomedia -- Physiology. Animal-orientation. Other Sub.: Theses -- Zoology. Status: Friday Harbor Theses QL430.5.T7 M87 1994 CHECK THE SHELVES Natural Sciences General Stacks QL3 .Th42526 CHECK THE SHELVES {Aux. Stacks - request at Suzzallo Central Circ} Thesis 42526 LIBRARY USE ONLY

Neural Correlates of Orientation to Water-flow in Tritonia diomedea

by James Alan Murray

Chairperson of the Supervisory Committee: Professor A. O. Dennis Willows Department of Zoology (now Biology)

The nudibranch gastropod Tritonia diomedea Bergh oriented to tidal flow in nature and to water flow in the laboratory. The slugs oriented by bending their bodies toward the upstream side, and crawling upstream (positive rheotaxis) to become aligned head first into the flow. Surgical ablation of identified nerves showed that sensory information important for proper orientation was carried by the lateral branch of Cerebral Nerve 2. CeN2 innervates the oral veil. Other cerebral nerves were not necessary for orientation to flow. Bilateral ablation of CeN2 eliminated orientation; unilateral ablation of CeN2 did not eliminate orientation or bias turning behavior. Cutting a pedal nerve on one side of the body biased turning away from that side, but the slug oriented to flow by turning toward the intact side until pointed upstream. Extracellular nerve recordings show that CeN2 responded to flow stimulation of the oral veil with bursts of action potentials from the periphery. CeN1 and 3 did not respond strongly to oral veil flow stimuli. Many pedal neurons responded to flow stimuli applied to the head and oral veil. Four pairs of identified pedal neurons were both preferentially sensitive to ipsilateral stimulation of the head with flow, and produced contractions of the foot and body wall that could serve to turn the slug into the flow. One of these four pairs, Left and Right Pedal neuron 3 (L&RPe3), was necessary for turning into flow. Photoinactivation of a single Pe3 did not eliminate orientation, but photoinactivation of both L&RPe3 eliminated significant orientation to flow. The activity of Pe3 correlated with ipsilateral contractions made during turns upstream. This dissertation is available via anonymous FTP (file transfer protocol). The document is formatted in Microsoft Word 5.1a with some color figures. To obtain a copy, see the top of this page. The author reserves all rights to publication.

I am most grateful to my advisor Dr. Dennis Willows for his generous financial, intellectual, maritime, and aeronautical support throughout this project, and for hot skones early on cold mornings. Thanks to my committee members Drs. Eliot Brenowitz, Alan Kohn, Bill Moody, Johnny Palka, and Thomas Quinn, especially Drs. Brenowitz and Kohn for critiquing the draft. Drs. Glen Brown, Ken Lohmann, Win Watson, and Randy Hewes provided intellectual inspiration, technical advice, and insightful criticism. Drs. Win Watson, Peter Getting, and Glen Brown generously loaned equipment. Thanks to Dr. Glen Brown for Fig 1 and to Karen Chalupnik for the artwork. All sorts of gratitude is due Elizabeth Olsen for editing and assistance with word processing. I thank Drs. Craig Staude and David Duggins for slug dowsing and innumerable acts of technical assistance. The Friday Harbor Labs staff including Sally Dickman, Joyce Smith, Dick Destaffany, and Scott Schwinge provided essential help in completing this project, along with FHL maintenance staff, and the staff of the Department of Zoology. Special thanks to Kathy Carr, Dianne Wilkinson, and the staff of the Natural Sciences library who were immensely helpful. Dennis Willows, Glen Brown, Jerry Mahoney, Michelle Woodbury, Nat Scholz, and Kenny Broad assisted in underwater collection of data, even when the water was wet. Lauw Klaassen and Dr. Andries ter Maat provided invaluable technical assistance with fine-wire techniques. I thank the Grass Foundation and the Department of Zoology (especially Dr. Bill Moody) for additional funds to attend meetings, and for tuition waivers courtesy of the State of Washington. I am always grateful to Katie O'Reilly, Dr. Christine Szych, Betsy Blinks, and Elizabeth Olsen for friendship I can always count on. Fellow "Slug Pirates of the Pacific Northwest" Dennis Willows, Ken Lohmann, Glen Brown, Laura Hurley, Dan Brumbaugh, Raz Popescu, and Elizabeth "Bounty Hunter" Olsen helped abduct slugs. Thanks to Dr. Ingrith Deyrup-Olsen, Betsy Blinks, Raz Popescu, and Andreas Beckmann for various degrees and amounts of German translation. Thanks to the scientists and staff of the Washington Department of Fisheries and Seattle Aquarium for sightings of slugs in Washington and BC waters. A hearty thank you to the San Juan Island community for making me feel at home in their middle kingdom between heaven and earth. This work was supported by grants from NIH and NSF to AOD Willows, and by NIH training grants to JA Murray.

This work is dedicated to my parents, for the work they did that allowed me to attend quality schools, and for their unending and realized faith that I will find a career doing what I enjoy. Their lessons of honesty and hard work have served me well, and have culminated in these pages.

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modified 4-8-05