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Time disparity sensitive behavior and its neural substrates of a pulse-type gymnotiform electric fish, Brachyhypopomus gauderio

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Abstract

Roles of the time coding electrosensory system in the novelty responses of a pulse-type gymnotiform electric fish, Brachyhypopomus, were examined behaviorally, physiologically, and anatomically. Brachyhypopomus responded with the novelty responses to small changes (100 μs) in time difference between electrosensory stimulus pulses applied to different parts of the body, as long as these pulses were given within a time period of ~500 μs. Physiological recording revealed neurons in the hindbrain and midbrain that fire action potentials time-locked to stimulus pulses with short latency (500–900 μs). These time-locked neurons, along with other types of neurons, were labeled with intracellular and extracellular marker injection techniques. Light and electron microscopy of the labeled materials revealed neural connectivity within the time coding system. Two types of time-locked neurons, the pear-shaped cells and the large cells converge onto the small cells in a hypertrophied structure, the mesencephalic magnocellular nucleus. The small cells receive a calyx synapse from a large cell at their somata and an input from a pear-shaped cell at the tip of their dendrites via synaptic islands. The small cells project to the torus semicircularis. We hypothesized that the time-locked neural signals conveyed by the pear-shaped cells and the large cells are decoded by the small cells for detection of time shifts occurring across body areas.

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Abbreviations

ABC:

Avidin-biotin complex

DAB:

Diaminobenzidine

ELL:

Electrosensory lateral line lobe

EM:

Electron microscopy or electron micrograph

EOD:

Electric organ discharge

GA:

Glutaraldehyde

LM:

Light microscopy or light micrograph

MMN:

Mesencephalic magnocellular nucleus

PB:

Phosphate buffer

PBS:

Phosphate buffer saline

PFA:

Paraformaldehyde

References

  • Aguilera PA, Caputi AA (2003) Electroreception in G. carapo: detection of changes in waveform of the electrosensory signals. J Exp Biol 206:989–998

    Article  PubMed  Google Scholar 

  • Alves-Gomes JA, Orti G, Haygood M, Heiligenberg W, Meyer A (1995) Phylogenetic analysis of the South American electric fishes (order Gymnotiformes) and the evolution of their electrogenic system: a synthesis based on morphology, electrophysiology, and mitochondrial sequence data. Mol Biol Evol 12(2):298–318

    PubMed  CAS  Google Scholar 

  • Amagai S, Friedman MA, Hopkins CD (1998) Time coding in the midbrain of mormyrid electric fish. I. Physiology and anatomy of cells in the nucleus exterolateralis pars anterior. J Comp Physiol 182:115–130

    Article  CAS  Google Scholar 

  • Baker CLJ (1980) Jamming avoidance behavior in gymnotoid electric fish with pulse-type discharges: sensory encoding for a temporal pattern discrimination. J Comp Physiol 136:165–181

    Article  Google Scholar 

  • Bastian J (1976) Frequency response characteristics of electroreceptors in weakly electric fish (Gymnotoidei) with a pulse discharge. J Comp Physiol 112:165–180

    Article  Google Scholar 

  • Carlson BA, Kawasaki M (2006) Stimulus selectivity is enhanced by voltage-dependent conductances in combination-sensitive neurons. J Neurophysiol 96:3362–3377

    Article  PubMed  Google Scholar 

  • Carlson BA, Hasan SM, Hollmann M, Miller DB, Harmon LJ, Arnegard ME (2011) Brain evolution triggers increased diversification of electric fishes. Science 332:583–586

    Article  PubMed  CAS  Google Scholar 

  • Carr CE, Boudreau RE (1993) Organization of the nucleus magnocellularis and the nucleus laminaris in the barn owl: encoding and measuring interaural time differences. J Comp Neurol 334:337–355

    Article  PubMed  CAS  Google Scholar 

  • Carr CE, Friedman MA (1999) Evolution of time coding systems. Neural Comput 11:1–20

    Article  PubMed  CAS  Google Scholar 

  • Carr CE, Heiligenberg W, Rose GJ (1986a) A time-comparison circuit in the electric fish midbrain. I. Behavior and physiology. J Neurosci 6:107–119

    CAS  Google Scholar 

  • Carr CE, Maler L, Taylor B (1986b) A time-comparison circuit in the electric fish midbrain. II. Functional morphology. J Neurosci 6:1372–1383

    CAS  Google Scholar 

  • Castelló ME, Caputi A, Trujillo-Cenóz O (1998) Structural and functional aspects of the fast electrosensory pathway in the electrosensory lateral line lobe of the pulse fish Gymnotus carapo. J Comp Neurol 401:549–563

    Article  PubMed  Google Scholar 

  • Castelló ME, Nogueira J, Trujillo-Cenóz O, Caputi AA (2008) Sensory processing in the fast electrosensory pathway of pulse gymnotids studied at multiple integrative levels. Comp Biochem Physiol A 151:370–380

    Article  Google Scholar 

  • Crampton WGR, Albert JS (2006) Evolution of electric signal diversity in gymnotiform fishes. In: Ladich F, Collin SP, Moller P, Kapoor BG (eds) Communication in Fishes, vol 2. Science Publishers, Enfield, pp 647–731

    Google Scholar 

  • Friedman MA, Hopkins CD (1995) Evidence for mechanisms of temporal analysis in the knollenorgan electrosensory system of mormyrid fish. In: Burrows M, Matheson T, Newland PL, Schuppe H (eds) Nervous systems and behavior. Georg Thieme Verlag, Stuttgart, p 419

    Google Scholar 

  • Friedman MA, Hopkins CD (1998) Neural substrates for species recognition in the time-coding electrosensory pathway of mormyrid electric fish. J Neurosci 18:1171–1185

    PubMed  CAS  Google Scholar 

  • Guo YX, Kawasaki M (1997) Representation of accurate temporal information in the electrosensory system of the African electric fish, Gymnarchus niloticus. J Neurosci 17:1761–1768

    PubMed  CAS  Google Scholar 

  • Heiligenberg W (1974) Electrolocation and jamming avoidance in a Hypopygus (Rhamphichthyidae, Gymnotoidei), an electric fish with pulse-type discharges. J Comp Physiol 91:223–240

    Article  Google Scholar 

  • Heiligenberg W (1980) The evaluation of electroreceptive feedback in a gymnotoid fish with pulse-type electric organ discharges. J Comp Physiol 138:173–185

    Article  Google Scholar 

  • Heiligenberg W (1991) Neural Nets in Electric fish. The MIT Press, Cambridge

    Google Scholar 

  • Heiligenberg W, Altes RA (1978) Phase sensitivity in electroreception. Science 199:1001–1004

    Article  PubMed  CAS  Google Scholar 

  • Heiligenberg W, Bastian J (1980) The control of Eigenmannia’s pacemaker by distributed evaluation of electroreceptive afferences. J Comp Physiol 136:113–133

    Article  Google Scholar 

  • Heiligenberg W, Baker C, Bastian J (1978) The jamming avoidance response in gymnotoid pulse-species: a mechanism to minimize the probability of pulse-train coincidence. J Comp Physiol 124:211–224

    Article  Google Scholar 

  • Hopkins CD (1986) Behavior of Mormyridae. In: Bullock TH, Heiligenberg W (eds) Electroreception. John Wiley & Sons, New York, pp 527–576

    Google Scholar 

  • Hopkins CD, Bass AH (1981) Temporal coding of species recognition signals in an electric fish. Science 212:85–87

    Article  PubMed  CAS  Google Scholar 

  • Hopkins CD, Comfort NC, Bastian J, Bass AH (1990) Functional analysis of sexual dimorphism in an electric fish, Hypopomus pinnicaudatus, order Gymnotiformes. Brain Behav Evol 35:350–367

    Article  PubMed  CAS  Google Scholar 

  • Kawasaki M (1993) Independently evolved jamming avoidance responses employ identical computational algorithms: a behavioral study of the African electric fish, Gymnarchus niloticus. J Comp Physiol 173:9–22

    Article  CAS  Google Scholar 

  • Kawasaki M (2009) Evolution of time-coding systems in weakly electric fishes. Zoolog Sci 26:587–599

    Article  PubMed  Google Scholar 

  • Kawasaki M, Guo Y-X (1998) Parallel projection of amplitude and phase information from the hindbrain to the midbrain of the African electric fish Gymnarchus niloticus. J Neurosci 18:7599–7611

    PubMed  CAS  Google Scholar 

  • Kawasaki M, Heiligenberg W (1989) Distinct mechanisms of modulation in a neuronal oscillator generate different social signals in the electric fish Hypopomus. J Comp Physiol 165:731–741

    Article  CAS  Google Scholar 

  • Kawasaki M, Matsushita A (2009) Behavioral sensitivity to time differences in the electrosensory system of a pulse type gymnotiform fish. Program No. 196.15. 2009 Neuroscience Meeting Planner Chigcago, IL: Society for Neuroscience, 2009 Online

  • Kuba H, Ishii TM, Ohmori H (2006) Axonal site of spike initiation enhances auditory coincidence detection. Nature 444:1069–1072

    Article  PubMed  CAS  Google Scholar 

  • Livingstone M, Hubel D (1988) Segregation of form, color, movement, and depth: anatomy, physiology, and perception. Science 240:740–749

    Article  PubMed  CAS  Google Scholar 

  • Matsushita A, Kawasaki M (2004) Unitary giant synapses embracing a single neuron at the convergent site of time-coding pathways of an electric fish, Gymnarchus niloticus. J Comp Neurol 472:140–155

    Article  PubMed  Google Scholar 

  • Model PG, Spira ME, Bennett MV (1972) Synaptic inputs to the cell bodies of the giant fibers of the hatchetfish. Brain Res 45:288–295

    Article  PubMed  CAS  Google Scholar 

  • Mugnaini E, Maler L (1987) Cytology and immunocytochemistry of the nucleus exterolateralis anterior of the mormyrid brain: possible role of GABAergic synapses in temporal analysis. Anat Embryol (Berl) 176:313–336

    Article  CAS  Google Scholar 

  • Perrone R, Macadar O, Silva A (2009) Social electric signals in freely moving dyads of Brachyhypopomus pinnicaudatus. J Comp Physiol 195:501–514

    Article  Google Scholar 

  • Réthelyi M, Szabo T (1973a) A particular nucleus in the mesencephalon of weakly electric fish, Gymnotus carapo (Gymnotidae, Pisces). Exp Brain Res 17:229–241

    Article  PubMed  Google Scholar 

  • Réthelyi M, Szabo T (1973b) Neurohistological analysis of the lateral line lobe in a weakly electric fish, Gymnotus carapo (Gymnotidae, Pisces). Exp Brain Res 18:323–339

    Article  PubMed  Google Scholar 

  • Rose GJ, Heiligenberg W (1985) Temporal hyperacuity in the electric sense of fish. Nature 318:178–180

    Article  PubMed  CAS  Google Scholar 

  • Rosenbluth J, Palay S (1961) The fine structure of nerve cell bodies and their myelin sheaths in the eighth nerve ganglion of the goldfish. J Biophys Biochem Cytol 9:853–877

    Article  PubMed  CAS  Google Scholar 

  • Sotelo C, Réthelyi M, Szabo T (1975) Morphological correlates of electrotonic coupling in the magnocellular mesencephalic nucleus of the weakly electric fish Gymnotus carapo. J Neurocytol 4:587–607

    Article  PubMed  CAS  Google Scholar 

  • Sun YJ, Komatsu S, Naito A, Watanabe SY (1996) Fine structures of perikaryal myelin sheaths on statoacoustic ganglion cells in 3-day-old chicks. Tohoku J Exp Med 180:309–317

    Article  PubMed  CAS  Google Scholar 

  • Takahashi T, Moiseff A, Konishi M (1984) Time and intensity cues are processed independently in the auditory system of the owl. J Neurosci 4:1781–1786

    PubMed  CAS  Google Scholar 

  • von der Emde G (1993) Capacitance discrimination in electrolocating weakly electric pulse-fish. Naturwissenschaften 80:231–233

    Article  Google Scholar 

  • von der Emde G (1998) Capacitance detection in the wave-type electric fish Eigenmannia during active electrolocation. J Comp Physiol 182:217–224

    Article  Google Scholar 

  • von der Emde G (1999) Active electrolocation of objects in weakly electric fish. J Exp Biol 202:1205–1215

    PubMed  Google Scholar 

  • von der Emde G, Zelick R (1995) Behavioral detection of electric signal waveform distortion in the weakly electric fish, Gnathonemus petersii. J Comp Physiol 177:493–501

    Article  Google Scholar 

  • Xu-Friedman MA, Hopkins CD (1999) Central mechanisms of temporal analysis in the knollenorgan pathway of mormyrid electric fish. J Exp Biol 202:1311–1318

    PubMed  Google Scholar 

  • Yager DD, Hopkins CD (1993) Directional characteristics of tuberous electroreceptors in the weakly electric fish, Hypopomus (Gymnotiformes). J Comp Physiol 173:401–414

    Article  CAS  Google Scholar 

  • Zhang Y, Kawasaki M (2007) Interruption of pacemaker signals is mediated by GABAergic inhibition of the pacemaker nucleus in the African electric fish Gymnarchus niloticus. J Comp Physiol 193:665–675

    Article  CAS  Google Scholar 

Download references

Acknowledgments

We thank two anonymous referees for critical reading of the manuscript. This work was supported by a grant from National Science Foundation IOS-0723356 to MK, and by the JSPS (Japan Society for the Promotion of Science) Grants-in-Aid for Scientific Research no. 22570073, and by a grant from the CPIS (Sokendai Center for the Promotion of Integrated Sciences) to AM. We also thank to Kentaro Arikawa for providing us with experimental space and equipment for anatomical studies. The histological materials other than those of Brachyhypopomus were prepared by Grace Kennedy and other members of Walter Heiligenberg’s laboratory in early 1990 s and donated to MK. All experiments were approved by the University of Virginia Animal Care Committee.

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Correspondence to Atsuko Matsushita.

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Fig. 6

Time-locked neurons are non-adaptive to high repetition rate of stimulus pulses. a Intracellular recording from a time-locked neuron showing one-to-one spike firing to a pulse train of 450 Hz. b Field potential in the MMN to doublet pulses separated by 2 ms. Note only slight reduction in amplitudes between field potentials indicated by two arrows. Asterisks show stimulus pulse artifacts. c The time interval between the two pulses in b was varied from 2 to 40 ms, and the magnitude of the field potential to the second pulse was normalized to the field potential to the first pulse. Results in one fish recorded at the ganglion and the MMN with normal amplitude and 15 times higher amplitude of stimulus pulses than the natural EOD (eps 325 KB)

Fig. 7

The pear-shaped cells. a–c, g–i show extracellularly labeled cells. a1 A 50-μm thick transverse section of the right side of the ELL. Somata of the pear-shaped cells are arranged in the layer I (black arrow). Their axons form a thick bundle running toward the midline (white arrow). a2 A magnified view of the box in a1. b An exceptional pear-shaped cell whose soma possessed a dendrite (arrow). c Two somata of labeled pear-shaped cells (inset), one of which was enlarged (asterisk). The soma is contacted by a calyx (C) terminal. Arrowheads indicate the interface of the contact. d A labeled calyx ending of an afferent nerve fiber embracing a soma of a pear-shaped cell (P). e Conventional EM showing chemical synapses (arrows) between an afferent terminal (Af) and a pear-shaped cell soma (P). f A somatic myelination (arrowheads) of a pear-shaped cell. Note that continuous myelination with the axon hillock (asterisk). g An axon bundle in the lateral lemniscus. h A transverse section more anterior to g. Axons of the pear-shaped cells running through the torus semicircularis (T) and terminating in the MMN (arrow). L, lateral lemniscus. i Other material showing axon bundles (arrowheads) of pear-shaped cells and their glomerular terminals in the MMN (eps 16642 KB)

Fig. 8

Glomerular terminals of pear-shaped cells in the MMN. a–d Intracellularly neurobiotin-injected terminals of pear-shaped cells in the MMN from four different materials. a A glomerular terminal. b Axonal branching observed at a deep location in the MMN. c1 Composite micrograph of projection processes of a pear-shaped cell. This terminal attached at least three large cells (short arrows). One of them is shown in c2 embedded in resin for EM (c3). Long arrows indicate densely glomerular terminals. c2 Resin-embedded vibratome section of the large cell soma in c1. The large cell soma (arrow) is attached by a labeled club ending (arrowhead). c3 EM view of the large cell (c2) (asterisk). The vacuole in the club ending is probably an artifact from tracer injection or following processing, because we have never seen it in the conventional EM. c4 An expanded view of the box in c3, showing two gap junctions (arrows). d1 Glomerular terminals of another pear-shaped cell. The glomerulus (arrow) was observed with EM (d2). d2 EM of the endings in a glomerulus (arrowheads), surrounded by membranous structures, synaptic island. d3 Enlarged view of the box in d2. Arrows indicate postsynaptic densities whose electron densities are a little thinner than that of the labeled presynaptic profile. Asterisks, postsynaptic elements (dendrites). e1 Conventional EM of a synaptic island. Asterisks, fragments of postsynaptic dendrites. P, Presynaptic ending of a pear-shaped cell. e2 Magnified view of the box in e1, showing two asymmetric chemical synapses. Asterisks, postsynaptic dendrites (eps 12989 KB)

Fig. 9

The morphology of large cells. a A transverse section of the MMN (delineated with broken line) stained with neutral red showing distribution of somata of the large cells. Approximately 70 somata were counted in this section. Inset: Magnified view of two somata. b A myelinated soma and two club endings forming input synapses (asterisks). The boxed area in b is enlarged in c where gap junctions (arrowheads) and an adherence junction (arrow) are seen. C, Club ending, L, large cell. d1, d2 Camera Lucida drawings of individual large cells projected onto the transverse plane. The rostrocaudal dimension of the large cells in d1 and d2 are 650 and 750 μm, respectively. e A large cell soma (L) with two initial segments (asterisks) and two input terminals (arrows). The two input terminals attached on the unmyelinated part of the soma (L). Note the continuous myelination over the soma (arrowheads), initial segments, and axons. f Light micrograph of the large cell drawn in d2 showing the soma and proximal axon of an intracellularly labeled large cell in a single 50-μm thick section. s, soma. g, h Calyx endings of axon collaterals of the labeled large cell drawn in d2. i1–i3 Three sections sampled from serially cut ultrathin sections of a labeled calyx ending (arrowheads). Note that the ending embraces a soma of a postsynaptic neuron (asterisks) which has a dendrite (arrow) (eps 15105 KB)

Fig. 10

The small cells. a A small cell receiving a calyx-ending via gap junctions. Boxed area in a1 is enlarged in a2. Note the continuous gap junction. b Another small cell with a dendrite (arrowheads) and axon (asterisk). Portions of a calyx ending attached to the soma (arrows). c Retrogradely labeled small cells. Almost all labeled cells in the MMN were observed to have a dendrite and an axon. Short arrows indicate the tufted tip of dendrites. Arrowheads indicate bundles containing small cell axons. Long arrows: thick axons of pear-shaped cells. d A biocytin-labeled small cell with a dendrite (white arrowhead) and axon (black arrowhead). The end of the dendrite forms a tuft (thick arrow). Small arrow, axon of other small cell. Inset: The tufted dendritic tip of another small cell. e The tufted dendritic tip of a labeled small cell. e1 LM showing a tufted end (arrowhead) that was observed with EM (e2 and e3). Asterisk indicates the soma. e2 An ultrathin section showing a contact of labeled ends and an unlabeled axon terminal (P). Note laminated membranous structures (asterisks) around the labeled profile, indicating the ‘synaptic island’. Boxed area is enlarged in e3, showing numerous synaptic vesicles (arrowheads) (eps 7843 KB)

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Matsushita, A., Pyon, G. & Kawasaki, M. Time disparity sensitive behavior and its neural substrates of a pulse-type gymnotiform electric fish, Brachyhypopomus gauderio . J Comp Physiol A 199, 583–599 (2013). https://doi.org/10.1007/s00359-012-0784-4

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