%0 Journal Article %J Acta neurobiologiae experimentalis %D 1993 %T The volitional nature of the simplest reflex. %A Jonathan Wolpaw %A Jonathan S. Carp %K behavior %K Brain %K conditioning %K human physiology %K Learning %K Memory %K motoneuron %K nature %K primate %K Reflex %K Spinal Cord %K spinal site %K supra spinal site %K vertebrate %X Recent studies suggest that none of the behaviors of the vertebrate CNS are fixed responses incapable of change. Even the simplest reflex of all, the two-neuron, monosynaptic spinal stretch reflex (SSR), undergoes adaptive change under appropriate circumstances. Operantly conditioned SSR change occurs gradually over days and weeks and is associated with a complex pattern of CNS plasticity at both spinal and supraspinal sites. %B Acta neurobiologiae experimentalis %V 53 %P 103–111 %G eng %U http://www.ncbi.nlm.nih.gov/pubmed/8317238