title: The effect of operant-conditioning balance training on the down-regulation of spinal H-reflexes in a spastic patient.
abstract: Spasticity in chronic hemiparetic stroke patients has primarily been treated pharmacologically. However, there is increasing evidence that physical rehabilitation can help manage hyper-excitability of reflexes (hyperreflexia), which is a primary contributor to spasticity. In the present study, one chronic hemiparetic stroke patient operantly conditioned the soleus H-reflex while training on a balance board for two weeks. The results showed a minimal decrease in the Hmax-Mmax ratio for both the affected and unaffected limb, indicating that the H-reflex was not significantly altered with training. Alternatively, paired-reflex depression (PRD), a measure of history-dependent changes in reflex excitability, could be conditioned. This was evident by the rightward shift and decreased slope of reflex excitability in the affected limb. The non-affected limb decreased as well, although the non-affected limb was very sensitive to PRD initially, whereas the affected limb was not. Based on these results, it was concluded that PRD is a better index of hyperreflexia, and this measurement could be more informative of synapse function than simple H-reflexes. This study presents a novel and non-pharmacological means of managing spasticity that warrants further investigation with the potential of being translated to the clinic.
authors.affiliation: Department of Kinesiology & Program in Neural Science, Indiana University, Bloomington, IN, 47405, USA.
authors.forename: Najmeh
authors.initials: N
authors.lastname: Hoseini
authors.affiliation: Department of Kinesiology & Program in Neural Science, Indiana University, Bloomington, IN, 47405, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Koceja
authors.affiliation: Department of Kinesiology & Program in Neural Science, Indiana University, Bloomington, IN, 47405, USA; Department of Kinesiology, Indiana University-Purdue University, Indianapolis, IN, 46202, USA. Electronic address: zariley@iupui.edu.
authors.forename: Zachary A
authors.initials: ZA
authors.lastname: Riley
mesh_terms: D001676:Biofeedback, Psychology; D003216:Conditioning, Operant / Q000502:physiology*; D015444:Exercise / Q000502:physiology; D006181:H-Reflex / Q000502:physiology*; D006801:Humans; D008297:Male; D009128:Muscle Spasticity / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D018482:Muscle, Skeletal / Q000502:physiology; D010291:Paresis / Q000150:complications / Q000628:therapy; D004856:Postural Balance / Q000502:physiology*; D011999:Recruitment, Neurophysiological / Q000502:physiology; D020521:Stroke / Q000150:complications; D055815:Young Adult