<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jonathan Wolpaw</style></author><author><style face="normal" font="default" size="100%">O'Keefe, J. A.</style></author><author><style face="normal" font="default" size="100%">Noonan, P. A.</style></author><author><style face="normal" font="default" size="100%">Sanders, M. G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adaptive plasticity in primate spinal stretch reflex: persistence.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of neurophysiology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Spinal Cord</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1986</style></year><pub-dates><date><style  face="normal" font="default" size="100%">02/1986</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/3950691</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">272–279</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Monkeys can gradually change the amplitude of the wholly segmental, largely monosynaptic, spinal stretch reflex (SSR) when confronted by a task requiring such change (15-19). Change develops over months and may reverse and redevelop at similarly slow rates. We investigated the persistence of SSR amplitude change over nonperformance periods of up to 38 days. Eight animals with chronic EMG electrodes learned to maintain elbow angle and a given level of biceps background EMG against constant extension torque. At random times, a brief additional extension torque pulse elicited the biceps SSR. In the control mode, reward always followed. Under the SSR increase or SSR decrease mode, reward occurred only if the absolute value of biceps EMG in the SSR interval was above or below a set value. Animals completed 3,000-6,000 trials/day over data-collection periods of 2-17 mo. Animals worked first under the control mode for up to 60 days and then under the SSR increase or SSR decrease mode for up to 274 days. Mode was switched once or twice more (SSR increase to SSR decrease or vice versa) over subsequent months. Animals responded to each SSR increase or SSR decrease mode exposure with gradual mode-appropriate change in SSR amplitude. Mode exposures were interrupted by gaps in performance of 10-38 days. Gaps produced transient 10- to 15% decreases in SSR amplitude under the control mode. This nonspecific decrease disappeared over the first week of postgap performance. Under the control mode, gaps had no other effects on SSR amplitude.(ABSTRACT TRUNCATED AT 250 WORDS)</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jonathan Wolpaw</style></author><author><style face="normal" font="default" size="100%">O'Keefe, J. A.</style></author><author><style face="normal" font="default" size="100%">Kieffer, V. A.</style></author><author><style face="normal" font="default" size="100%">Sanders, M. G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Reduced day-to-day variation accompanies adaptive plasticity in the primate spinal stretch reflex.</style></title><secondary-title><style face="normal" font="default" size="100%">Neuroscience letters</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Learning</style></keyword><keyword><style  face="normal" font="default" size="100%">Memory</style></keyword><keyword><style  face="normal" font="default" size="100%">plasticity</style></keyword><keyword><style  face="normal" font="default" size="100%">primate</style></keyword><keyword><style  face="normal" font="default" size="100%">spinal reflex</style></keyword><keyword><style  face="normal" font="default" size="100%">stretch reflex</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1985</style></year><pub-dates><date><style  face="normal" font="default" size="100%">03/1985</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/3991057</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">54</style></volume><pages><style face="normal" font="default" size="100%">165–171</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Monkeys can change the amplitude of the spinal stretch reflex (SSR), or M1, when reward is made contingent on amplitude. The present study demonstrates that reduced SSR day-to-day variation accompanies such adaptive SSR change. This finding supports the assumption that initial, phase I, SSR change results from contingency-appropriate stabilization of tonic activity in relevant descending spinal cord pathways.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jonathan Wolpaw</style></author><author><style face="normal" font="default" size="100%">Kieffer, V. A.</style></author><author><style face="normal" font="default" size="100%">Seegal, R. F.</style></author><author><style face="normal" font="default" size="100%">Braitman, D. J.</style></author><author><style face="normal" font="default" size="100%">Sanders, M. G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adaptive plasticity in the spinal stretch reflex.</style></title><secondary-title><style face="normal" font="default" size="100%">Brain research</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Learning</style></keyword><keyword><style  face="normal" font="default" size="100%">Memory</style></keyword><keyword><style  face="normal" font="default" size="100%">plasticity</style></keyword><keyword><style  face="normal" font="default" size="100%">primate</style></keyword><keyword><style  face="normal" font="default" size="100%">spinal reflex</style></keyword><keyword><style  face="normal" font="default" size="100%">stretch reflex</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1983</style></year><pub-dates><date><style  face="normal" font="default" size="100%">05/1983</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/6860948</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">267</style></volume><pages><style face="normal" font="default" size="100%">196–200</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Monkeys can change the amplitude of the spinal stretch reflex without change in initial alpha motor neuron tone, as measured by EMG, or in initial muscle length. Change is apparent in 5-10 days, continues to develop over weeks, and persists during inactive periods. Spinal stretch reflex change may be a valuable system for studying the neuronal and synaptic bases of an adaptive change in primate CNS function.</style></abstract></record></records></xml>