TY - JOUR
T1 - The electric organ discharges of the gymnotiform fishes
T2 - II. Eigenmannia
AU - Assad, C.
AU - Rasnow, B.
AU - Stoddard, P. K.
AU - Bower, J. M.
N1 - Funding Information:
Acknowledgements We thank two anonymous reviewers for their thoughtful comments. Financial support came from NSF grant IBN-9319968 to JMB and from FIU Foundation and NIH/ NIGMS-GM08205-11 grants to PKS. All experiments were approved by the Caltech Institutional Animal Care and Use Committee and are in accordance with the NIH guidelines for experiments involving vertebrate animals.
PY - 1998/10
Y1 - 1998/10
N2 - We present detailed measurements of the electric organ discharge of the weakly electric fish, Eigenmannia sp. These maps illuminate, with high resolution in both space and time, the electric organ discharge potential and electric field patterns in the water about the fish and on the skin surface itself. The results demonstrate that the electric organ discharge of Eigenmannia approximates a simple oscillating dipole, which confirms previous descriptions and assumptions, but is in contrast to the electric organ discharges of several other gymnotiform species. Over each cycle of Eigenmannia's electric organ discharge, the electric field amplitude measured at any point near the fish oscillates from positive to negative, but the field vector remains nearly constant in direction. This electric organ discharge charge pattern is correlated with known anatomical and physiological features of the fish's electric organ, and confirms that the activation of electrocytes comprising the organ is well synchronized. As a result, the relatively simple electric organ discharge leads to a fairly uniform pattern of electrosensory stimuli along the body surface, which may facilitate central processing of electrosensory images. Electric organ discharge maps and animations resulting from this series of studies are available via the Internet (http:// www.bbb.caltech.edu/ElectricFish, or www.fiu.edu/ ~stoddard/electricfish.html).
AB - We present detailed measurements of the electric organ discharge of the weakly electric fish, Eigenmannia sp. These maps illuminate, with high resolution in both space and time, the electric organ discharge potential and electric field patterns in the water about the fish and on the skin surface itself. The results demonstrate that the electric organ discharge of Eigenmannia approximates a simple oscillating dipole, which confirms previous descriptions and assumptions, but is in contrast to the electric organ discharges of several other gymnotiform species. Over each cycle of Eigenmannia's electric organ discharge, the electric field amplitude measured at any point near the fish oscillates from positive to negative, but the field vector remains nearly constant in direction. This electric organ discharge charge pattern is correlated with known anatomical and physiological features of the fish's electric organ, and confirms that the activation of electrocytes comprising the organ is well synchronized. As a result, the relatively simple electric organ discharge leads to a fairly uniform pattern of electrosensory stimuli along the body surface, which may facilitate central processing of electrosensory images. Electric organ discharge maps and animations resulting from this series of studies are available via the Internet (http:// www.bbb.caltech.edu/ElectricFish, or www.fiu.edu/ ~stoddard/electricfish.html).
KW - Electric field
KW - Electric fish
KW - Electroreception
KW - Etomidate
KW - Gymnotiformes
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U2 - 10.1007/s003590050268
DO - 10.1007/s003590050268
M3 - Article
C2 - 9809452
AN - SCOPUS:0032191066
VL - 183
SP - 419
EP - 432
JO - Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology
JF - Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology
SN - 0340-7594
IS - 4
ER -