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Comparison of motor patterns in the intact and deafferented flight system of the locust

II. Intracellular recordings from flight motoneurons

Summary

  1. 1.

    A preparation is described which allows intracellular recording from motoneurons during flight in tethered locusts with normal sensory input from wing receptors (Fig. 1).

  2. 2.

    The pattern of synaptic input to all the main flight motoneurons was recorded (Fig. 3) and compared to the synaptic input to the same motoneurons following deafferentation (Fig. 6). Clear differences were observed, particularly in the input pattern to elevator motoneurons. In intact animals elevator motoneurons received a powerful and rapid depolarization shortly after the termination of depressor activity. This phasic depolarization of elevators was not generated in deafferented preparations. Instead a distinctly different phasic depolarization occurred immediately preceding depressor activity. Transitions between the intact and the deafferented patterns of synaptic input were observed when flight slowed down in some intact and partially deafferented animals (Fig. 8). During these transitions both components of synaptic input to elevators could be observed.

  3. 3.

    The changes in the pattern of synaptic input to elevator motoneurons following deafferentation explain all the major changes in the flight motor pattern observed in EMG recordings from flight muscles. In particular, the delayed and variable onset of elevator activity following depressor activity in deafferented preparations is due to the absence of the early component of synaptic input to elevators.

  4. 4.

    We conclude that afferent input from wing receptors is necessary for the generation of the phasic depolarization which occurs in elevator motoneurons of intact animals. This result leads us to question the adequacy of the concept of central pattern generation for explaining the production of the flight motor pattern in locusts.

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References

  1. Arshavsky YI, Beloozerova IN, Orlovsky GN, Panchin YV, Pavlova GA (1985) Control of locomotion in marine molluscClione limacina. I. Efferent activity during actual and fictitious swimming. Exp Brain Res 58:255–262

  2. Bacon J, Möhl B (1983) The tritocerebral commissure giant (TCG) wind-sensitive interneurone in the locust. I. Its activity in straight flight. J Comp Physiol 150:439–452

  3. Bässler U, Wegner U (1983) Motor output of the denervated ventral nerve cord in the stick insectCarausius morosus. J Exp Biol 105:127–145

  4. Burrows M (1975) Monosynaptic connexions between wing stretch receptors and flight motoneurones of the locust. J Exp Biol 62:189–219

  5. Getting PA, Lennard PR, Hume RI (1980) Central pattern generator mediating swimming inTritonia. I. Identification and synaptic interactions. J Neurophysiol 44:151–164

  6. Gettrup E (1966) Sensory regulation of wing twisting in locusts. J Exp Biol 44:1–16

  7. Hedwig B, Pearson KG (1984) Patterns of synaptic input to identified flight motoneurons in the locust. J Comp Physiol A 154:745–760

  8. Kien J, Altman JS (1979) Connections of the locust wing tegula with metathoracic flight motoneurons. J Comp Physiol 133:299–210

  9. Kristan WB, Stent GS (1976) Peripheral feedback in the leech swimming rhythm. Cold Spring Harbour Symp Quant Biol 40:663–674

  10. Möhl B (1985) The role of proprioception in locust flight control. II. Information signalled by forewing stretch receptors during flight. J Comp Physiol A 156:103–116

  11. Neumann L, Möhl B, Nachtigall W (1982) Quick phase-specific influence of the tegula on the locust flight motor. Naturwissenschaften 69:393–394

  12. Pabst H (1965) Elektrophysiologische Untersuchungen des Streckrezeptors am Flügelgelenk der WanderheuschreckeLocusta migratoria. Z Vergl Physiol 50:498–541

  13. Pearson KG (1985) Are there central pattern generators for walking and flight in insects? In: Barnes WJP, Gladden MH (eds) Feedback and motor control in invertebrates and vertebrates. Croom Helm, London, pp 307–316

  14. Pearson KG, Wolf H (1987) Comparison of motor patterns in the intact and deafferented flight system of the locust. I. Electromyographic analysis. J Comp Physiol A 160:259–268

  15. Pearson KG, Reye DN, Robertson RM (1983) Phase-dependent influences of wing stretch receptors on flight rhythm in the locust. J Neurophysiol 49:1168–1181

  16. Peterson EL (1983) Generation and coordination of heartbeat timing oscillation in the medicinal leech. I. Oscillation in isolated ganglia. J Neurophysiol 49:611–626

  17. Peterson EL (1983) Generation and coordination of heartbeat timing oscillation in the medicinal leech. II. Intersegmental coordination. J Neurophysiol 49:627–638

  18. Selverston AI, Moulins M (1985) Oscillatory neural networks. Annu Rev Physiol 47:29–48

  19. Wendler G (1974) The influence of proprioceptive feedback on locust flight coordination. J Comp Physiol 88:173–200

  20. Wendler G (1983) The locust flight system: functional aspects of sensory input and methods of investigation. In: Nachtigall W (ed) Biona Report 2. Gustav Fischer, Stuttgart, pp 113–125

  21. Willows AOD, Dorsett DA, Hoyle G (1973) The neuronal basis of behavior inTritonia. III. Neuronal mechanism of a fixed action pattern. J Neurobiol 4:255–285

  22. Wilson DM (1961) The central nervous control of flight in a locust. J Exp Biol 38:471–490

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Wolf, H., Pearson, K.G. Comparison of motor patterns in the intact and deafferented flight system of the locust. J. Comp. Physiol. 160, 269–279 (1987). https://doi.org/10.1007/BF00609732

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Keywords

  • Intact Animal
  • Synaptic Input
  • Motor Pattern
  • Central Pattern Generation
  • Afferent Input