title: Operant conditioning of primate H-reflex: phases of development.
abstract: This study sought to determine whether operantly conditioned change in the primate triceps surae (TS) H-reflex develops in distinct phases. Data from 20 animals in which the TS H-reflex in one leg was trained up (i.e., HRup mode) and 18 in which it was trained down (i.e., HRdown mode) were averaged to define H-reflex behavior in trained and control legs. In HRup animals, the trained-leg H-reflex showed a large phase I increase in the first two days followed by gradual phase II increase that continued for weeks. The control-leg H-reflex appeared to show much smaller phase I and phase II increases. In HRdown animals, the trained-leg H-reflex decreased gradually over weeks, while the control-leg H-reflex appeared to increase within 2 days and did not change from then on. The initial rapid increase in the HRdown control leg suggested that two early events occurred in the HRdown trained leg: a nonspecific increase like that in the control leg and an operantly conditioned mode-specific decrease. These two effects may have obscured each other, so that H-reflex size in the HRdown trained leg did not drop rapidly in the first few days. These results improve understanding of adaptive H-reflex change as an operantly conditioned phenomenon, and provide encouragement and direction for efforts to reproduce and study the phenomenon in reduced or anesthetized preparations.
authors.affiliation: Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201.
authors.forename: J R
authors.initials: JR
authors.lastname: Wolpaw
authors.forename: D M
authors.initials: DM
authors.lastname: Maniccia
authors.forename: T
authors.initials: T
authors.lastname: Elia
mesh_terms: D000818:Animals; D003216:Conditioning, Operant / Q000502:physiology*; D006181:H-Reflex / Q000502:physiology*; D006614:Hindlimb; D008254:Macaca nemestrina / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D013116:Spinal Cord / Q000502:physiology; D013997:Time Factors