electric organ

Summary

Summary: In about 250 species of electric fishes, modified muscle fibers forming disklike multinucleate plates arranged in stacks like batteries in series and embedded in a gelatinous matrix. A large torpedo ray may have half a million plates. Muscles in different parts of the body may be modified, i.e., the trunk and tail in the electric eel, the hyobranchial apparatus in the electric ray, and extrinsic eye muscles in the stargazers. Powerful electric organs emit pulses in brief bursts several times a second. They serve to stun prey and ward off predators. A large torpedo ray can produce of shock of more than 200 volts, capable of stunning a human. (Storer et al., General Zoology, 6th ed, p672)

Top Publications

  1. Bettendorff L, Wins P, Schoffeniels E. Thiamine triphosphatase from Electrophorus electric organ is anion-dependent and irreversibly inhibited by 4,4'-diisothiocyanostilbene-2,2'disulfonic acid. Biochem Biophys Res Commun. 1988;154:942-7 pubmed
    Thiamine triphosphatase (TTPase) from membranes isolated from the main electric organ of E. electricus is activated about 8 fold by NO3-, I- and SCN- while SO42- is inhibitory. Activating anions shift the pH optimum of the enzyme from 5...
  2. von der Emde G, Schwarz S, Gomez L, Budelli R, Grant K. Electric fish measure distance in the dark. Nature. 1998;395:890-4 pubmed
    ..Our results suggest a novel mechanism for depth perception that can be achieved with a single, stationary two-dimensional array of detectors. ..
  3. Caputi A, Aguilera P, Castello M. Probability and amplitude of novelty responses as a function of the change in contrast of the reafferent image in G carapo. J Exp Biol. 2003;206:999-1010 pubmed
    ..We conclude that contrast discrimination in the electrosensory system of G. carapo obeys the general principle of appreciating any instantaneous input by the input's departure from a moving average of past images...
  4. Franchina C. Ontogeny of the electric organ discharge and the electric organ in the weakly electric pulse fish Brachyhypopomus pinnicaudatus (Hypopomidae, Gymnotiformes). J Comp Physiol A. 1997;181:111-9 pubmed
    I recorded the electric organ discharges (EODs) of 331 immature Brachyhypopomus pinnicaudatus 6-88 mm long. Larvae produced head-positive pulses 1.3 ms long at 7 mm (6 days) and added a second, small head-negative phase at 12 mm...
  5. Capurro A, Longtin A, Bagarinao E, Sato S, Macadar O, Pakdaman K. Variability of the electric organ discharge interval duration in resting Gymnotus carapo. Biol Cybern. 2001;84:309-21 pubmed
    We recorded the electric organ discharges of resting Gymnotus carapo specimens. We analyzed the time series formed by the sequence of interdischarge intervals...
  6. Gibbs M. Lateral line receptors: where do they come from developmentally and where is our research going?. Brain Behav Evol. 2004;64:163-81 pubmed
  7. Ramcharitar J, Tan E, Fortune E. Effects of global electrosensory signals on motion processing in the midbrain of Eigenmannia. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2005;191:865-72 pubmed
    ..This occurred in both the ampullary and tuberous systems, despite the fact that the ampullary afferents to the torus originate in a single ELL map whereas the tuberous afferents emerge from three maps...
  8. Chen L, House J, Krahe R, Nelson M. Modeling signal and background components of electrosensory scenes. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2005;191:331-45 pubmed
    ..The model is computationally fast and can be used to estimate the spatiotemporal pattern of activation across the entire electroreceptor array of the fish during natural behaviors...
  9. Bastian J. Pyramidal-cell plasticity in weakly electric fish: a mechanism for attenuating responses to reafferent electrosensory inputs. J Comp Physiol A. 1995;176:63-73 pubmed
    ..Electroreceptor afferent responses to electric organ discharge amplitude modulations caused by movement of the animal's tail were compared to responses caused by ..

More Information

Publications106 found, 100 shown here

  1. Van der Kloot W. Loading and recycling of synaptic vesicles in the Torpedo electric organ and the vertebrate neuromuscular junction. Prog Neurobiol. 2003;71:269-303 pubmed
    ..The amount of ACh loaded into recycling vesicles in the readily releasable pool decreases during stimulation. The ACh content of the vesicles can be varied over eight-fold range without changing vesicle size. ..
  2. Jun J, Longtin A, Maler L. Precision measurement of electric organ discharge timing from freely moving weakly electric fish. J Neurophysiol. 2012;107:1996-2007 pubmed publisher
    ..Pulse-type electric fish generate a train of discrete and stereotyped electric organ discharges (EOD) to sense their surroundings actively, and rapid modulation of the discharge rate occurs while ..
  3. Tricas T, Michael S, Sisneros J. Electrosensory optimization to conspecific phasic signals for mating. Neurosci Lett. 1995;202:129-32 pubmed
  4. Caputi A, Budelli R. Peripheral electrosensory imaging by weakly electric fish. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2006;192:587-600 pubmed
    ..of the fish's body shapes the image in two different ways: by funneling the current generated by the electric organ to the sensory surface, it increases the fields rostrally, thus enhancing the perturbation produced by nearby ..
  5. Kawasaki M. Independently evolved jamming avoidance responses employ identical computational algorithms: a behavioral study of the African electric fish, Gymnarchus niloticus. J Comp Physiol A. 1993;173:9-22 pubmed
    ..Both fishes, nevertheless, gradually shift the frequency of electric organ discharge away when they encounter a neighbor of a similar discharge frequency...
  6. Ros E, Aleu J, Gomez De Aranda I, Canti C, Pang Y, Marsal J, et al. Effects of bis(7)-tacrine on spontaneous synaptic activity and on the nicotinic ACh receptor of Torpedo electric organ. J Neurophysiol. 2001;86:183-9 pubmed
    ..Miniature endplate potentials (MEPPs) were recorded extracellularly on slices of electric organ of Torpedo marmorata...
  7. Maler L. Receptive field organization across multiple electrosensory maps. I. Columnar organization and estimation of receptive field size. J Comp Neurol. 2009;516:376-93 pubmed publisher
    The electric fish Apteronotus leptorhynchus emits a high-frequency electric organ discharge (EOD) sensed by specialized electroreceptors (P-units)...
  8. Castelló M, Rodríguez Cattáneo A, Aguilera P, Iribarne L, Pereira A, Caputi A. Waveform generation in the weakly electric fish Gymnotus coropinae (Hoedeman): the electric organ and the electric organ discharge. J Exp Biol. 2009;212:1351-64 pubmed publisher
    This article deals with the electric organ and its discharge in Gymnotus coropinae, a representative species of one of the three main clades of the genus...
  9. Franchina C, Stoddard P. Plasticity of the electric organ discharge waveform of the electric fish Brachyhypopomus pinnicaudatus. I. Quantification of day-night changes. J Comp Physiol A. 1998;183:759-68 pubmed
    The electric organ discharge of the gymnotiform fish Brachyhypopomus pinnicaudatus is a biphasic waveform. The female's electric organ discharge is nearly symmetric but males produce a longer second phase than first phase...
  10. Rodríguez Cattáneo A, Aguilera P, Cilleruelo E, Crampton W, Caputi A. Electric organ discharge diversity in the genus Gymnotus: anatomo-functional groups and electrogenic mechanisms. J Exp Biol. 2013;216:1501-15 pubmed publisher
    Previous studies describe six factors accounting for interspecific diversity of electric organ discharge (EOD) waveforms in Gymnotus...
  11. Budelli R, Caputi A, Gomez L, Rother D, Grant K. The electric image in Gnathonemus petersii. J Physiol Paris. 2002;96:421-9 pubmed
  12. Arnegard M, Jackson B, Hopkins C. Time-domain signal divergence and discrimination without receptor modification in sympatric morphs of electric fishes. J Exp Biol. 2006;209:2182-98 pubmed
    ..Reproductively isolated mormyrid fishes from Gabon's Brienomyrus species flock emit distinctive electric organ discharges (EODs) thought to function in species and sex recognition...
  13. Middleton J, Longtin A, Benda J, Maler L. The cellular basis for parallel neural transmission of a high-frequency stimulus and its low-frequency envelope. Proc Natl Acad Sci U S A. 2006;103:14596-601 pubmed
    ..This circuit could, in principle, be implemented in the auditory or visual cortex by the previously identified biophysics of cortical interneurons. ..
  14. Rodríguez Cattáneo A, Caputi A. Waveform diversity of electric organ discharges: the role of electric organ auto-excitability in Gymnotus spp. J Exp Biol. 2009;212:3478-89 pubmed publisher
    This article shows that differences in the waveforms of the electric organ discharges (EODs) from two taxa are due to the different responsiveness of their electric organs (EOs) to their previous activity (auto-excitability)...
  15. Tricas T, New J. Sensitivity and response dynamics of elasmobranch electrosensory primary afferent neurons to near threshold fields. J Comp Physiol A. 1998;182:89-101 pubmed
    ..We argue that these properties reflect evolutionary adaptations in elasmobranch fishes to enhance detection of prey, communication and social interactions, and possibly electric-mediated geomagnetic orientation. ..
  16. Kirschbaum F, Schwassmann H. Ontogeny and evolution of electric organs in gymnotiform fish. J Physiol Paris. 2008;102:347-56 pubmed publisher
    ..This zone is generating electrocytes continuously so that, as a consequence, the relative proportion of electric organ to muscle increases greatly. In 45mm long E...
  17. Faure G, Copic A, Le Porrier S, Gubensek F, Bon C, Krizaj I. Crotoxin acceptor protein isolated from Torpedo electric organ: binding properties to crotoxin by surface plasmon resonance. Toxicon. 2003;41:509-17 pubmed
    ..have suggested the existence of a 48 kDa crotoxin-binding protein in the presynaptic membranes of the electric organ of Torpedo marmorata...
  18. Chacron M, Toporikova N, Fortune E. Differences in the time course of short-term depression across receptive fields are correlated with directional selectivity in electrosensory neurons. J Neurophysiol. 2009;102:3270-9 pubmed publisher
    ..Because short-term depression is ubiquitous in the central nervous systems of vertebrate animals, it may be a common mechanism used for the generation of directional selectivity and other spatiotemporal computations. ..
  19. Bastian J. Electrolocation in the presence of jamming signals: behavior. J Comp Physiol A. 1987;161:811-24 pubmed
    ..Broad-band noise and sinusoidal signals, different in frequency by a few Hz from the animal's personal electric organ discharge (DF stimuli), were used to jam the tuberous electroreceptors...
  20. Sadoulet Puccio H, Khurana T, Cohen J, Kunkel L. Cloning and characterization of the human homologue of a dystrophin related phosphoprotein found at the Torpedo electric organ post-synaptic membrane. Hum Mol Genet. 1996;5:489-96 pubmed
    ..In addition, antibodies against either the Torpedo 87 kDa protein or human dystrobrevin demonstrate that at least three of the splice forms are translated as proteins in human brain tissue extracts. ..
  21. Gómez L, Budelli R, Grant K, Caputi A. Pre-receptor profile of sensory images and primary afferent neuronal representation in the mormyrid electrosensory system. J Exp Biol. 2004;207:2443-53 pubmed
    Afferent responses to the fish's own electric organ discharge were explored in the electrosensory lobe of the mormyrid fish Gnathonemus petersii...
  22. Babineau D, Lewis J, Longtin A. Spatial acuity and prey detection in weakly electric fish. PLoS Comput Biol. 2007;3:e38 pubmed
    ..Whereas large-object spacing is favorable for discriminating the individual elements of a scene, small spacing can increase the fish's ability to resolve a single target object against this background. ..
  23. Hitschfeld E, Stamper S, Vonderschen K, Fortune E, Chacron M. Effects of restraint and immobilization on electrosensory behaviors of weakly electric fish. ILAR J. 2009;50:361-72 pubmed
    ..These fishes use a specialized electric organ to produce an electric field that is typically below 1 volt/cm and serves in many behaviors including social ..
  24. Stoddard P, Rasnow B, Assad C. Electric organ discharges of the gymnotiform fishes: III. Brachyhypopomus. J Comp Physiol A. 1999;184:609-30 pubmed
    ..Spatio-temporal false-color maps of the electric organ discharges measured on the skin show that the electric field is not a simple dipole in Brachyhypopomus...
  25. Ratnam R, Nelson M. Nonrenewal statistics of electrosensory afferent spike trains: implications for the detection of weak sensory signals. J Neurosci. 2000;20:6672-83 pubmed
    ..This study emphasizes the importance of characterizing spike train variability on multiple time scales, particularly when considering limits on the detectability of weak sensory signals. ..
  26. Aguilera P, Caputi A. Electroreception in G carapo: detection of changes in waveform of the electrosensory signals. J Exp Biol. 2003;206:989-98 pubmed
    Electric fish evaluate the near environment by detecting changes in their self-generated electric organ discharge...
  27. Zakon H. Insight into the mechanisms of neuronal processing from electric fish. Curr Opin Neurobiol. 2003;13:744-50 pubmed
    ..Their central sensory circuits are specialized to process amplitude modulated signals, to detect microsecond variations in spike timing, and are dynamically reconfigured depending on the stimulus parameters. ..
  28. Arnegard M, Bogdanowicz S, Hopkins C. Multiple cases of striking genetic similarity between alternate electric fish signal morphs in sympatry. Evolution. 2005;59:324-43 pubmed
    ..populations of mormyrid fishes that are morphologically cryptic in sympatry but produce alternate types of electric organ discharge (EOD)...
  29. Nelson M, Maciver M. Prey capture in the weakly electric fish Apteronotus albifrons: sensory acquisition strategies and electrosensory consequences. J Exp Biol. 1999;202:1195-203 pubmed
  30. Unguez G, Zakon H. Skeletal muscle transformation into electric organ in S. macrurus depends on innervation. J Neurobiol. 2002;53:391-402 pubmed
    The cells of the electric organ, called electrocytes, of the weakly electric fish Sternopygus macrurus derive from the fusion of mature fast muscle fibers that subsequently disassemble and downregulate their sarcomeric components...
  31. Sullivan J, Lavoué S, Arnegard M, Hopkins C. AFLPs resolve phylogeny and reveal mitochondrial introgression within a species flock of African electric fish (Mormyroidea: Teleostei). Evolution. 2004;58:825-41 pubmed
    ..Mapping the two forms of electric organ found in this group onto the AFLP tree suggests that posteriorly innervated electrocytes with nonpenetrating ..
  32. Markham M, McAnelly M, Stoddard P, Zakon H. Circadian and social cues regulate ion channel trafficking. PLoS Biol. 2009;7:e1000203 pubmed publisher
  33. Nazarian J, Berry D, Sanjari S, Razvi M, Brown K, Hathout Y, et al. Evolution and comparative genomics of subcellular specializations: EST sequencing of Torpedo electric organ. Mar Genomics. 2011;4:33-40 pubmed publisher
    ..C15orf24 protein localized to the murine postsynaptic sarcolemma. We show a novel approach towards identifying proteins expressed at a subcellular specialization using evolutionary diversity of organ function and cross-species mapping. ..
  34. Carlson B. Neuroanatomy of the mormyrid electromotor control system. J Comp Neurol. 2002;454:440-55 pubmed
  35. von der Emde G. Non-visual environmental imaging and object detection through active electrolocation in weakly electric fish. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2006;192:601-12 pubmed
    ..Electric images depend on size, distance, shape, and material of objects and on the morphology of the electric organ and the fish's body...
  36. Gabbiani F, Metzner W, Wessel R, Koch C. From stimulus encoding to feature extraction in weakly electric fish. Nature. 1996;384:564-7 pubmed
    ..We conclude that the sensory neurons are specialized to acquire information accurately with little processing, whereas the following stage extracts behaviourally relevant features, thus performing a nonlinear pattern-recognition task...
  37. Pereira A, Centurión V, Caputi A. Contextual effects of small environments on the electric images of objects and their brain evoked responses in weakly electric fish. J Exp Biol. 2005;208:961-72 pubmed
    ..These facts may be explained by the presence of adaptive responses observed at the slow pathway in the electrosensory lobe...
  38. Sanguinetti Scheck J, Pedraja E, Cilleruelo E, Migliaro A, Aguilera P, Caputi A, et al. Fish geometry and electric organ discharge determine functional organization of the electrosensory epithelium. PLoS ONE. 2011;6:e27470 pubmed publisher
    ..Differently from mormyriformes electric fish, gymnotiformes have an electric organ distributed along a large portion of the body, which fires sequentially...
  39. Moortgat K, Keller C, Bullock T, Sejnowski T. Submicrosecond pacemaker precision is behaviorally modulated: the gymnotiform electromotor pathway. Proc Natl Acad Sci U S A. 1998;95:4684-9 pubmed
    ..modulators of neural precision? We address this question in the most regular biological oscillator known, the electric organ command nucleus in the brainstem of wave-type gymnotiform fish...
  40. Unguez G, Zakon H. Phenotypic conversion of distinct muscle fiber populations to electrocytes in a weakly electric fish. J Comp Neurol. 1998;399:20-34 pubmed
    In most groups of electric fish, the electric organ (EO) derives from striated muscle cells that suppress many muscle phenotypic properties...
  41. Stoddard P, Markham M, Salazar V. Serotonin modulates the electric waveform of the gymnotiform electric fish Brachyhypopomus pinnicaudatus. J Exp Biol. 2003;206:1353-62 pubmed
    ..electric fish Brachyhypopomus pinnicaudatus communicates with a sexually dimorphic electric waveform, the electric organ discharge (EOD). Males display pronounced circadian rhythms in the amplitude and duration of their EODs...
  42. Mantipragada S, Horvath L, Arias H, Schwarzmann G, Sandhoff K, Barrantes F, et al. Lipid-protein interactions and effect of local anesthetics in acetylcholine receptor-rich membranes from Torpedo marmorata electric organ. Biochemistry. 2003;42:9167-75 pubmed
    ..These displacements represent an intrinsic difference in affinity of the local anesthetics for the lipid-protein interface because the membrane partition coefficients are in the order benzocaine > tetracaine approximately procaine...
  43. Carlson B. Electric signaling behavior and the mechanisms of electric organ discharge production in mormyrid fish. J Physiol Paris. 2002;96:405-19 pubmed
    Mormyrid fish communicate and navigate using electric organ discharges (EODs)...
  44. Snyder J, Nelson M, Burdick J, MacIver M. Omnidirectional sensory and motor volumes in electric fish. PLoS Biol. 2007;5:e301 pubmed
    ..We propose that the ratio of the sensory volume to the motor volume provides insight into behavioral control strategies across all animals...
  45. Kim J, Laney C, Curry J, Unguez G. Expression of myogenic regulatory factors in the muscle-derived electric organ of Sternopygus macrurus. J Exp Biol. 2008;211:2172-84 pubmed publisher
    ..macrurus...
  46. Bacelo J, Engelmann J, Hollmann M, von der Emde G, Grant K. Functional foveae in an electrosensory system. J Comp Neurol. 2008;511:342-59 pubmed publisher
    ..Our data support the hypothesis that the chin appendage and nasal region are functionally distinct electrosensory foveae...
  47. Sîrbulescu R, Ilieş I, Zupanc G. Structural and functional regeneration after spinal cord injury in the weakly electric teleost fish, Apteronotus leptorhynchus. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2009;195:699-714 pubmed publisher
    ..Functional regeneration was demonstrated by recovery of the amplitude of the electric organ discharge, a behavior generated by spinal motoneurons...
  48. Pereira A, Caputi A. Imaging in electrosensory systems. Interdiscip Sci. 2010;2:291-307 pubmed publisher
    ..In the active electrosensory systems of fish these images are formed by the fish's own electric organ discharge...
  49. Bastian J, Courtright J, Crawford J. Commissural neurons of the electrosensory lateral line lobe of Apteronotus leptorhynchus: morphological and physiological characteristics. J Comp Physiol A. 1993;173:257-74 pubmed
    ..and labeling showed that ovoid cells discharge spontaneously at high rates, fire at preferred phases to the electric organ discharge, and respond to increased receptor afferent input with short latency partially adapting excitation...
  50. Hopkins C. Convergent designs for electrogenesis and electroreception. Curr Opin Neurobiol. 1995;5:769-77 pubmed
    ..for electrogenesis and electroreception has focused on the structure of electric organs, the neural circuitry controlling the pacemaker driving the electric organ, and the neural circuitry underlying time coding of electric waveforms.
  51. Hann R, Pagán O, Gregory L, Jacome T, Eterovic V. The 9-arginine residue of alpha-conotoxin GI is responsible for its selective high affinity for the alphagamma agonist site on the electric organ acetylcholine receptor. Biochemistry. 1997;36:9051-6 pubmed
    The two agonist-binding domains of the electric organ nicotinic acetylcholine receptor are located at the alphagamma and alphadelta subunit interfaces...
  52. McAnelly M, Zakon H. Coregulation of voltage-dependent kinetics of Na(+) and K(+) currents in electric organ. J Neurosci. 2000;20:3408-14 pubmed
    The electric organ cells of Sternopygus generate action potentials whose durations vary over a fourfold range. This variation in action potential duration is the basis for individual variation in a communication signal...
  53. Carlson B, Hopkins C, Thomas P. Androgen correlates of socially induced changes in the electric organ discharge waveform of a mormyrid fish. Horm Behav. 2000;38:177-86 pubmed
    Weakly electric fish from the family Mormyridae produce pulsatile electric organ discharges (EODs) for use in communication...
  54. Markham M, Stoddard P. Adrenocorticotropic hormone enhances the masculinity of an electric communication signal by modulating the waveform and timing of action potentials within individual cells. J Neurosci. 2005;25:8746-54 pubmed
    ..Gymnotiform electric fish modulate their electric organ discharges (EODs) by reshaping the electric discharges of excitable cells in the periphery...
  55. McAnelly M, Zakon H. Androgen modulates the kinetics of the delayed rectifying K+ current in the electric organ of a weakly electric fish. Dev Neurobiol. 2007;67:1589-97 pubmed
    Weakly electric fish such as Sternopygus macrurus utilize a unique signal production system, the electric organ (EO), to navigate within their environment and to communicate with conspecifics...
  56. Chacron M, Bastian J. Population coding by electrosensory neurons. J Neurophysiol. 2008;99:1825-35 pubmed publisher
    ..In particular, we show that the number of correlated bursts within a given time window could be used by postsynaptic neurons to distinguish between both stimulus categories...
  57. Ruxton G. Non-visual crypsis: a review of the empirical evidence for camouflage to senses other than vision. Philos Trans R Soc Lond B Biol Sci. 2009;364:549-57 pubmed publisher
    ..Hence, I conclude that crypsis is a concept that can usefully be applied to senses other than vision, and that this is a field very much worthy of more investigation...
  58. Sarkis J, Salto C. Characterization of a synaptosomal ATP diphosphohydrolase from the electric organ of Torpedo marmorata. Brain Res Bull. 1991;26:871-6 pubmed
    A true ecto-apyrase (ATP diphosphohydrolase, EC 3.6.1.5) enzyme was found in the synaptosomal fraction from the electric organ of the electric ray Torpedo marmorata...
  59. Zakon H, Unguez G. Development and regeneration of the electric organ. J Exp Biol. 1999;202:1427-34 pubmed
    The electric organ has evolved independently from muscle in at least six lineages of fish...
  60. McAnelly L, Silva A, Zakon H. Cyclic AMP modulates electrical signaling in a weakly electric fish. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2003;189:273-82 pubmed
    Many species of electric fish show diurnal or socially elicited variation in electric organ discharge amplitude. In Sternopygus macrurus, activation of protein kinase A by 8-bromo-cAMP increases electrocyte sodium current magnitude...
  61. Stoddard P, Markham M, Salazar V, Allee S. Circadian rhythms in electric waveform structure and rate in the electric fish Brachyhypopomus pinnicaudatus. Physiol Behav. 2007;90:11-20 pubmed
    ..to express day-night oscillations in their discharge rates, and in the amplitude and duration of individual electric organ discharges (EODs)...
  62. Kelly M, Babineau D, Longtin A, Lewis J. Electric field interactions in pairs of electric fish: modeling and mimicking naturalistic inputs. Biol Cybern. 2008;98:479-90 pubmed publisher
  63. Hopkins C. Design features for electric communication. J Exp Biol. 1999;202:1217-28 pubmed
    ..that electric signals do not propagate, but exist as electrostatic fields, means that, unlike sound signals, electric organ discharges produce no echoes or reverberations...
  64. Stoddard P. Predation enhances complexity in the evolution of electric fish signals. Nature. 1999;400:254-6 pubmed
    ..Thus a signal element that evolved for crypsis has itself been modified by sexual selection...
  65. Aguilera P, Castello M, Caputi A. Electroreception in Gymnotus carapo: differences between self-generated and conspecific-generated signal carriers. J Exp Biol. 2001;204:185-98 pubmed
    Local electric fields generated by the electric organ discharge of Gymnotus carapo were explored at selected points on the skin of an emitter fish ('local self-generated fields') and on the skin of a conspecific ('local conspecific-..
  66. Bell C. Memory-based expectations in electrosensory systems. Curr Opin Neurobiol. 2001;11:481-7 pubmed
    ..Evidence from all three groups of fish indicates that the negative images are mediated by plasticity at parallel fiber synapses...
  67. Krahe R, Kreiman G, Gabbiani F, Koch C, Metzner W. Stimulus encoding and feature extraction by multiple sensory neurons. J Neurosci. 2002;22:2374-82 pubmed
    ..There, stimulus-induced coincident activity can improve the extraction of behaviorally relevant features from the stimulus...
  68. Caputi A, Castelló M, Aguilera P, TRUJILLO CENOZ O. Electrolocation and electrocommunication in pulse gymnotids: signal carriers, pre-receptor mechanisms and the electrosensory mosaic. J Physiol Paris. 2002;96:493-505 pubmed
    ..Differences in carrier waveform may be used to distinguish between reafferent and communication signals...
  69. Chacron M, Maler L, Bastian J. Feedback and feedforward control of frequency tuning to naturalistic stimuli. J Neurosci. 2005;25:5521-32 pubmed
    ..Thus, with spatially extensive stimuli, these cells preferentially respond to the higher-frequency components of the receptor-afferent input...
  70. Caputi A, Castelló M, Aguilera P, Pereira C, Nogueira J, Rodríguez Cattáneo A, et al. Active electroreception in Gymnotus omari: imaging, object discrimination, and early processing of actively generated signals. J Physiol Paris. 2008;102:256-71 pubmed publisher
    ..In this review we summarize our findings in pulse gymnotids' active electroreception and outline a primary agenda for the next research...
  71. Markham M, Allee S, Goldina A, Stoddard P. Melanocortins regulate the electric waveforms of gymnotiform electric fish. Horm Behav. 2009;55:306-13 pubmed publisher
    ..Overall, these results strongly suggest that the HPI regulates the EOD communication signal, and demonstrate that circulating melanocortin peptides enhance the electrocyte discharge waveform...
  72. Zakon H, Thomas P, Yan H. Electric organ discharge frequency and plasma sex steroid levels during gonadal recrudescence in a natural population of the weakly electric fish Sternopygus macrurus. J Comp Physiol A. 1991;169:493-9 pubmed
    ..b>Electric organ discharge (EOD) frequencies were recorded, blood samples were taken for analysis of steroid titers, and gonads ..
  73. von der Emde G, Schwarz S. Imaging of objects through active electrolocation in Gnathonemus petersii. J Physiol Paris. 2002;96:431-44 pubmed
    ..During active electrolocation, fish produce a series of brief electric signals, electric organ discharges (EOD), with an electric organ in their tail...
  74. Nazarian J, Hathout Y, Vertes A, Hoffman E. The proteome survey of an electricity-generating organ (Torpedo californica electric organ). Proteomics. 2007;7:617-627 pubmed publisher
    Torpedo californica is a species in class Chondrichthyes. Electric rays have evolved the electric organ, which is similar to the mammalian neuromuscular junction (NMJ)...
  75. Salazar V, Stoddard P. Sex differences in energetic costs explain sexual dimorphism in the circadian rhythm modulation of the electrocommunication signal of the gymnotiform fish Brachyhypopomus pinnicaudatus. J Exp Biol. 2008;211:1012-20 pubmed publisher
    ..Because the electric signal constitutes a significant fraction of the energy budget, energy savings, along with predation avoidance, provides an adaptive basis for the production of circadian rhythms in electric signals...
  76. Hupé G, Lewis J. Electrocommunication signals in free swimming brown ghost knifefish, Apteronotus leptorhynchus. J Exp Biol. 2008;211:1657-67 pubmed publisher
    ..ghost knifefish, Apteronotus leptorhynchus, are a species of weakly electric fish that produce a continuous electric organ discharge (EOD) that is used in navigation, prey capture and communication...
  77. Arnegard M, Zwickl D, Lu Y, Zakon H. Old gene duplication facilitates origin and diversification of an innovative communication system--twice. Proc Natl Acad Sci U S A. 2010;107:22172-7 pubmed publisher
    ..sodium channel gene (Scn4aa), which arose by whole-genome duplication, was neofunctionalized for expression in electric organ and subsequently experienced strong positive selection...
  78. Crampton W, Lovejoy N, Waddell J. Reproductive character displacement and signal ontogeny in a sympatric assemblage of electric fish. Evolution. 2011;65:1650-66 pubmed publisher
  79. Wong C. Electrical stimulation of the preoptic area in Eigenmannia: evoked interruptions in the electric organ discharge. J Comp Physiol A. 2000;186:81-93 pubmed
    The functional role of the basal forebrain and preoptic regions in modulating the normally regular electric organ discharge was determined by focal brain stimulation in the weakly electric fish, Eigenmannia...
  80. Franchina C, Salazar V, Volmar C, Stoddard P. Plasticity of the electric organ discharge waveform of male Brachyhypopomus pinnicaudatus. II. Social effects. J Comp Physiol A. 2001;187:45-52 pubmed
    Many electric fish produce sexually dimorphic electric organ discharges...
  81. Ardanaz J, Silva A, Macadar O. Temperature sensitivity of the electric organ discharge waveform in Gymnotus carapo. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2001;187:853-64 pubmed
    ..In this study, we aim to describe the role of temperature upon electric organ discharge waveform in Gymnotus carapo, order Gymnotiformes, family Gymnotidae, and to analyze its interactions ..
  82. Escalada A, Navarro P, Ros E, Aleu J, Solsona C, Martín Satué M. Gadolinium inhibition of ecto-nucleoside triphosphate diphosphohydrolase activity in Torpedo electric organ. Neurochem Res. 2004;29:1711-4 pubmed
    ..E-NTPDase activity has been described in Torpedo electric organ electrocytes...
  83. Tan E, Nizar J, Carrera G E, Fortune E. Electrosensory interference in naturally occurring aggregates of a species of weakly electric fish, Eigenmannia virescens. Behav Brain Res. 2005;164:83-92 pubmed
    ..The median difference in electric organ discharge frequencies between nearby Eigenmannia during the day was 23 Hz in black water habitats, 41 Hz in ..
  84. Pusch R, von der Emde G, Hollmann M, Bacelo J, Nöbel S, Grant K, et al. Active sensing in a mormyrid fish: electric images and peripheral modifications of the signal carrier give evidence of dual foveation. J Exp Biol. 2008;211:921-34 pubmed publisher
    Weakly electric fish generate electric fields with an electric organ and perceive them with cutaneous electroreceptors. During active electrolocation, nearby objects are detected by the distortions they cause in the electric field...
  85. Longtin A, Middleton J, Cieniak J, Maler L. Neural dynamics of envelope coding. Math Biosci. 2008;214:87-99 pubmed publisher
    ..The model is modified from previous models by stimulus reducing contrast in order to make it sufficiently linear to agree with the experimental data...
  86. Changeux J. Allosteric receptors: from electric organ to cognition. Annu Rev Pharmacol Toxicol. 2010;50:1-38 pubmed publisher
    ..Theoretical models of cognitive functions are proposed that link the molecular to the cognitive level. The report ends with a discussion on nicotinic receptors and the pharmacology of the future...
  87. Savard M, Krahe R, Chacron M. Neural heterogeneities influence envelope and temporal coding at the sensory periphery. Neuroscience. 2011;172:270-84 pubmed publisher
    ..Our results show that heterogeneities in peripheral neuronal populations can have dramatic consequences on the nature of the neural code...
  88. Gallant J, Hopkins C, Deitcher D. Differential expression of genes and proteins between electric organ and skeletal muscle in the mormyrid electric fish Brienomyrus brachyistius. J Exp Biol. 2012;215:2479-94 pubmed publisher
    ..In spite of the similarity in the physiology and function of EOs in mormyrids and gymnotiforms, this study indicates that the mechanisms of development in the two groups may be considerably different...
  89. Caputi A, Silva A, Macadar O. The electric organ discharge of Brachyhypopomus pinnicaudatus. The effects of environmental variables on waveform generation. Brain Behav Evol. 1998;52:148-58 pubmed
    The electric organ discharge of Brachyhypopomus pinnicaudatus was studied by recording (1) the discharge field potentials in water at different conductivities and temperatures and (2) the spatiotemporal pattern of electromotive forces of ..
  90. Bastian J. Plasticity of feedback inputs in the apteronotid electrosensory system. J Exp Biol. 1999;202:1327-37 pubmed
    Weakly electric fish generate an electric field surrounding their body by means of an electric organ typically located within the trunk and tail...
  91. Terleph T, Moller P. Effects of social interaction on the electric organ discharge in a mormyrid fish, Gnathonemus petersii (Mormyridae, Teleostei). J Exp Biol. 2003;206:2355-62 pubmed
    ..This paper documents socially mediated changes in the electric organ discharge (EOD) of subadult Gnathonemus petersii under non-breeding environmental conditions...
  92. Graff C, Kaminski G, Gresty M, Ohlmann T. Fish perform spatial pattern recognition and abstraction by exclusive use of active electrolocation. Curr Biol. 2004;14:818-23 pubmed
    The field generated by the electric organ of weakly electric fish varies with the electrical properties of nearby objects. Correspondingly, current fluxes in this field differentially stimulate the electroreceptors in the fish's skin...