02012nas a2200229   4500008004100000022001400041245004900055210004800104260001200152300001100164490000800175520137600183653003401559653001301593653002501606653001901631653002301650653001801673100002201691700002101713856004801734       2015                        eng d  a1875-785500aTargeted neuroplasticity for rehabilitation.0 aTargeted neuroplasticity for rehabilitation  c03/2015  a157-720 v2183 a<p>An operant-conditioning protocol that bases reward on the electromyographic response produced by a specific CNS pathway can change that pathway. For example, in both animals and people, an operant-conditioning protocol can increase or decrease the spinal stretch reflex or its electrical analog, the H-reflex. Reflex change is associated with plasticity in the pathway of the reflex as well as elsewhere in the spinal cord and brain. Because these pathways serve many different behaviors, the plasticity produced by this conditioning can change other behaviors. Thus, in animals or people with partial spinal cord injuries, appropriate reflex conditioning can improve locomotion. Furthermore, in people with spinal cord injuries, appropriate reflex conditioning can trigger widespread beneficial plasticity. This wider plasticity appears to reflect an iterative process through which the multiple behaviors in the individual's repertoire negotiate the properties of the spinal neurons and synapses that they all use. Operant-conditioning protocols are a promising new therapeutic method that could complement other rehabilitation methods and enhance functional recovery. Their successful use requires strict adherence to appropriately designed procedures, as well as close attention to accommodating and engaging the individual subject in the conditioning process.</p>10aactivity-dependent plasticity10aH-Reflex10aoperant conditioning10aRehabilitation10aspinal cord injury10aspinal reflex1 aThompson, Aiko, K1 aWolpaw, Jonathan  uhttp://www.ncbi.nlm.nih.gov/pubmed/2589013602554nas a2200241   4500008004100000022001400041245016400055210006900219260001200288300001200300490000800312520178000320653001302100653001502113653001902128653001602147653001502163100002102178700002202199700002102221700002202242856004802264       2014                        eng d  a1522-159800aOperant conditioning of the soleus H-reflex does not induce long-term changes in the gastrocnemius H-reflexes and does not disturb normal locomotion in humans.0 aOperant conditioning of the soleus Hreflex does not induce longt  c09/2014  a1439-460 v1123 a<p>In normal animals, operant conditioning of the spinal stretch reflex or the H-reflex has lesser effects on synergist muscle reflexes. In rats and people with incomplete spinal cord injury (SCI), soleus H-reflex operant conditioning can improve locomotion. We studied in normal humans the impact of soleus H-reflex down-conditioning on medial (MG) and lateral gastrocnemius (LG) H-reflexes and on locomotion. Subjects completed 6 baseline and 30 conditioning sessions. During conditioning trials, the subject was encouraged to decrease soleus H-reflex size with the aid of visual feedback. Every sixth session, MG and LG H-reflexes were measured. Locomotion was assessed before and after conditioning. In successfully conditioned subjects, the soleus H-reflex decreased 27.2%. This was the sum of within-session (task dependent) adaptation (13.2%) and across-session (long term) change (14%). The MG H-reflex decreased 14.5%, due mainly to task-dependent adaptation (13.4%). The LG H-reflex showed no task-dependent adaptation or long-term change. No consistent changes were detected across subjects in locomotor H-reflexes, EMG activity, joint angles, or step symmetry. Thus, in normal humans, soleus H-reflex down-conditioning does not induce long-term changes in MG/LG H-reflexes and does not change locomotion. In these subjects, task-dependent adaptation of the soleus H-reflex is greater than it is in people with SCI, whereas long-term change is less. This difference from results in people with SCI is consistent with the fact that long-term change is beneficial in people with SCI, since it improves locomotion. In contrast, in normal subjects, long-term change is not beneficial and may necessitate compensatory plasticity to preserve satisfactory locomotion.</p>10aLearning10aplasticity10aRehabilitation10aSpinal Cord10asynergists1 aMakihara, Yukiko1 aSegal, Richard, L1 aWolpaw, Jonathan1 aThompson, Aiko, K  uhttp://www.ncbi.nlm.nih.gov/pubmed/24944216