01504nas a2200217   4500008004100000022001400041245009100055210006900146260001200215300001400227490000800241520088100249653001301130653001101143653001501154653001201169653001801181653001901199100002101218856004701239       1983                        eng d  a0006-899300aAdaptive plasticity in the primate spinal stretch reflex: reversal and re-development.0 aAdaptive plasticity in the primate spinal stretch reflex reversa  c11/1983  a299–3040 v2783 aMonkeys can gradually increase or decrease the amplitude of the segmentally mediated spinal stretch reflex (SSR) without change in initial muscle length or background EMG activity. Both increase (under the SSR increases mode) and decrease (under the SSR decreases mode) occur slowly, progressing steadily over weeks. The present study investigated reversal and re-development of SSR amplitude change. Over a period of months, following collection of control data, monkeys were exposed to one mode, then to the other, and then to the first mode again. Development, reversal, and re-development of change all took place over weeks, following very similar courses. These data are consistent with the hypothesis that persistent segmental alteration underlies SSR amplitude change. Such persistent segmental alteration would constitute a technically accessible substrate of memory.10aLearning10aMemory10aplasticity10aprimate10aspinal reflex10astretch reflex1 aWolpaw, Jonathan  uhttp://www.ncbi.nlm.nih.gov/pubmed/6640320