Reactivity of sensorimotor oscillations is altered in children with hemiplegic cerebral palsy: A magnetoencephalographic study

Abstract

Cerebral palsy (CP) is characterized by difficulty in control of movement and posture due to brain damage during early development. In addition, tactile discrimination deficits are prevalent in CP. To study the function of somatosensory and motor systems in CP, we compared the reactivity of sensorimotor cortical oscillations to median nerve stimulation in 12 hemiplegic CP children vs. 12 typically developing children using magnetoencephalography. We also determined the primary cortical somatosensory and motor representation areas of the affected hand in the CP children using somatosensory-evoked magnetic fields and navigated transcranial magnetic stimulation, respectively. We hypothesized that the reactivity of the sensorimotor oscillations in alpha (10 Hz) and beta (20 Hz) bands would be altered in CP and that the beta-band reactivity would depend on the individual pattern of motor representation. Accordingly, in children with CP, suppression and rebound of both oscillations after stimulation of the contralateral hand were smaller in the lesioned than intact hemisphere. Furthermore, in two of the three children with CP having ipsilateral motor representation, the beta- but not alpha-band modulations were absent in both hemispheres after affected hand stimulation suggesting abnormal sensorimotor network interactions in these individuals. The results are consistent with widespread alterations in information processing in the sensorimotor system and complement current understanding of sensorimotor network development after early brain insults. Precise knowledge of the functional sensorimotor network organization may be useful in tailoring individual rehabilitation for people with CP.

Children with cerebral palsy have uncharacteristic somatosensory cortical oscillations after stimulation of the hand mechanoreceptors

“…Our results indicate that the somatosensory cortical oscillations in the beta frequency range were abnormal in the children with CP, while alpha-theta responses seemed relatively intact. Similar exploratory results for the beta frequency were recently reported for a cohort of children with hemiplegic CP that underwent a median nerve stimulation paradigm (Pihko et al, 2014). Together these results imply that aberrations in somatosensory beta oscillatory activity may play a role in the tactile discrimination deficiencies often seen in children with CP.…”

“…These studies have identified that the somatosensory evoked-potentials/fields for the hand are diminished, and in some cases latent in children with CP (Kulak et al, 2005; Kulack et al, 2006; Riquelme and Montoya, 2010; Teflioudi et al, 2011; Maitre et al, 2012; Pihko et al, 2014; Papadelis et al, 2014). We have previously reported similar results for the foot (Kurz and Wilson, 2011; Kurz et al, 2012).…”

“…Far fewer studies have explored how the perinatal brain injury may also affect the oscillatory somatosensory activity that occurs after peripheral somatosensations are applied to the hand. A preliminary study conducted by Pihko and colleagues (2014) suggested that the alpha and beta oscillatory activity within the hand region of somatosensory cortices might be diminished in the damaged hemisphere of children with CP that have a hemiplegic presentation. While these exploratory results are enlightening, the electric median nerve stimulation paradigm employed in this initial investigation causes a broad stimulation of the somatosensory receptors, which does not allow for quantifying how the stimulation of specific sensory receptors found in the hand (i.e., mechanoreceptors, vibrotactile, etc.)…”

Somatosensory Misrepresentation Associated with Chronic Pain: Spatiotemporal Correlates of Sensory Perception in a Patient following a Complex Regional Pain Syndrome Spread

“…Furthermore, the interactions within the sensorimotor network are also disturbed (27). A recent study employed a multimodal neuroimaging approach and showed changes in somatotopy in cerebral palsy children (28).…”

Estimulação transcraniana não invasiva em indivíduos com paralisia cerebral: uma revisão integrativa da literatura

“…Por outro lado, a EMT tem sido utilizada na PC para realizar mapeamento cerebral, determinando o tipo/padrão de organização cortical. A EMT de pulso simples, em associação com a imagem por ressonância magnética (IRM), foi empregada na análise do mapeamento cerebral e avaliação da função da mão de indivíduos com PC unilateral 42,43,44,45,46 . A EMT parece mostrar-se um recurso importante para obter um prognóstico precoce nessa população 44,45 .…”