Deafferentation studies on motor activity in the chick. I. Activity pattern of hindlimbs

✍ Scribed by Narayanan, C. H. ;Malloy, R. B.

• Publisher: John Wiley and Sons
• Year: 1974
• Tongue: English
• Weight: 960 KB
• Volume: 189
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1401890204

✦ Synopsis

Abstract

Neural crest precursors of dorsal root ganglia at lumbosacral levels of the spinal cord of chick embryos were destroyed by superficial cauterization at very early stages (52–64 hours) in order to study the influence of afferent input from the periphery on activity patterns of the hindlimbs during embryonic, hatching and post‐hatching periods. Neither total nor local activity of the hindlimbs in deafferented chick embryos showed any significant difference quantitatively from those of control embryos between 9 and 17 days of incubation. These embryos exhibited typical prehatching and hatching behavior except the final climax stage of hatching in which the embryo normally cracks the shell around the air space and emerges. The experimental embryos were unable to hatch by themselves. In hatched chicks, legs were incapable of making alternate stepping movements. These observations, discussed in the light of other experimental evidences, suggest that afferent input from the periphery is probably involved in the patterning of coordinated activity of the legs in the chick.