Brain Plasticity following Intensive Bimanual Therapy in Children with Hemiparesis: Preliminary Evidence

Abstract

Neuroplasticity studies examining children with hemiparesis (CH) have focused predominantly on unilateral interventions. CH also have bimanual coordination impairments with bimanual interventions showing benefits. We explored neuroplasticity following hand-arm bimanual intensive therapy (HABIT) of 60 hours in twelve CH (6 females, mean age 11 ± 3.6 y). Serial behavioral evaluations and MR imaging including diffusion tensor (DTI) and functional (fMRI) imaging were performed before, immediately after, and at 6-week follow-up. Manual skills were assessed repeatedly with the Assisting Hand Assessment, Children's Hand Experience Questionnaire, and Jebsen-Taylor Test of Hand Function. Beta values, indicating the level of activation, and lateralization index (LI), indicating the pattern of brain activation, were computed from fMRI. White matter integrity of major fibers was assessed using DTI. 11/12 children showed improvement after intervention in at least one measure, with 8/12 improving on two or more tests. Changes were retained in 6/8 children at follow-up. Beta activation in the affected hemisphere increased at follow-up, and LI increased both after intervention and at follow-up. Correlations between LI and motor function emerged after intervention. Increased white matter integrity was detected in the corpus callosum and corticospinal tract after intervention in about half of the participants. Results provide first evidence for neuroplasticity changes following bimanual intervention in CH.

Improvements in upper extremity function in children with unilateral spastic cerebral palsy after intensive training correlates with interhemispheric connectivity

“…Furthermore, the efficacy of an intervention on hand function may also depend on the lateralization of the corticospinal tract (CST) [15] although the latter was found not to be a predictor of upper limb functions following HABIT [6] or CIMT [16]. Nonetheless, the result of these studies reinforces the importance to study other possible structures involved in hand function changes [8,13,17].…”

Motor, sensory and executive function brain networks in children with unilateral cerebral palsy

“…Here we have identified a further 22 studies assessing the CST (results of studies in the previous review are not discussed here). In unilateral CP ten studies showed significantly reduced FA in the non-dominant CST 108-110, 112, 114, 169-173 ; eight studies also demonstrated increased MD 108,109,112,[169][170][171][172]174 ; five studies demonstrated reduced streamline count 109,112,169,171,174 ; one study demonstrated reduced volume and cross sectional area 175 , and one study demonstrated a change in Apparent Fibre Density (a metric derived from constrained spherical deconvolution) 112 . One study demonstrated increased MD in the dominant CST in unilateral CP 172 .…”

“…In 174 . This study also demonstrated a correlation between streamline counts of interhemispheric connections and intrahemispheric connections.…”

“…This has been used in conjunction with structural connectivity measured by diffusion MRI 114,182 . This technique can be used to give an index of laterality 170,171,174 . Laterality indices were shown to correlate with FA in the posterior limb of the internal capsule 174 as well as improve with constraint induced movement therapy (along with diffusion MRI measures) 170 .…”

“…This technique can be used to give an index of laterality 170,171,174 . Laterality indices were shown to correlate with FA in the posterior limb of the internal capsule 174 as well as improve with constraint induced movement therapy (along with diffusion MRI measures) 170 . Resting state motor networks were shown to be altered in both unilateral and bilateral CP, with greater change in the non-dominant hemisphere in unilateral CP 171 .…”