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Experimental Brain Research

, Volume 100, Issue 1, pp 1–6 | Cite as

New observations on input to spino-cervical tract neurons from muscle afferents

  • I. Hammar
  • Z. Szabo Läckberg
  • E. Jankowska
Original Paper

Abstract

Peripheral input to spino-cervical tract (SCT) neurons located in the L4 and L5 segments of the cat spinal cord was investigated using both extracellular and intracellular recording. The main aim was to find out whether midlumbar SCT neurons are excited monosynaptically not only by cutaneous afferents but also by group II muscle afferents, as in the sacral segments but apparently not in the caudal lumbar segments. Input from group II muscle afferents was found in 73% of investigated neurons; the latencies of excitation by group II afferents were compatible with a monosynaptic coupling between these afferents and 62% of neurons. The majority of the midlumbar SCT neurons were excited by group II afferents of the quadriceps and deep peroneal nerves. The predominant monosynaptic input from cutaneous afferents to the same neurons was from the saphenous nerve.

Key words

Spinal cord Ascending tracts Spinocervical neurons Group II muscle afferents Cat 

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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • I. Hammar
    • 1
  • Z. Szabo Läckberg
    • 1
  • E. Jankowska
    • 1
  1. 1.Department of PhysiologyUniversity of GöteborgGöteborgSweden

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