title: Speculations surrounding a spinal reflex.
abstract: A method has been developed for measuring the Ia fibre input/motoneurone output relationship for the soleus H-reflex in healthy human volunteers. The shift in the relationship during weak toe extension, and in some subjects during weak plantar flexion, indicates the imposition of an inhibitory mechanism, presumably presynaptic. From these observations, and others previously made on long-loop reflexes, it is argued that the inhibitory mechanism may have evolved to suppress unwanted information from the periphery, not only during movement but in the resting state, and that this development was a necessary accompaniment of encephalisation.
authors.affiliation: Department of Electrical Engineering, McMaster University, Hamilton, ON, Canada L8N 3Z5.
authors.forename: Hubert
authors.initials: H
authors.lastname: DeBruin
authors.forename: Winnie
authors.initials: W
authors.lastname: Fu
authors.forename: Victoria
authors.initials: V
authors.lastname: Galea
authors.forename: Alan
authors.initials: A
authors.lastname: McComas
mesh_terms: D000818:Animals; D005075:Biological Evolution; D004558:Electric Stimulation / Q000379:methods; D004576:Electromyography / Q000379:methods; D006801:Humans; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000502:physiology* / Q000528:radiation effects; D012018:Reflex / Q000502:physiology* / Q000528:radiation effects; D013116:Spinal Cord / Q000502:physiology*