Back to Search
Start Over
Brain Activation Sequences Following Electrical Limb Stimulation of Normal and Paraplegic Subjects
- Source :
- NeuroImage. 16:115-129
- Publication Year :
- 2002
- Publisher :
- Elsevier BV, 2002.
-
Abstract
- In current clinical practice the degree of paraplegia or quadriplegia is objectively determined with transcranial magnetic stimulation (TMS) and somatosensory-evoked potentials (SSEP). We measured the MEG signal following electrical stimulation of upper and lower limbs in two normal and three clinically complete paraplegic subjects. From the MEG signal we computed distributed estimates of brain activity and identified foci just behind the central sulcus consistent in location with primary somatosensory (SI) for arm and foot and secondary somatosensory (SII) areas. Activation curves were computed from regions of interest defined around these areas. Activation of the SI foot area was observed in normal and paraplegic subjects when the upper limb was stimulated. Surprisingly, for each paraplegic subject, stimulation below the lesion was followed by cortical activations. These activations were weak, only loosely time-locked to the stimulus and were seen intermittently behind the central sulcus and nearby cortical areas. Statistical analysis of tomographic solutions and activation curves showed consistent responses following foot stimulation in one paraplegic (PS1) and intermittently in another paraplegic subject. We repeated the same experiment for PS1 in a different laboratory and the results from the analysis of foot stimulation from both laboratories revealed statistically significant focal cortical response only in the contralateral SI foot area.
- Subjects :
- Adult
Male
Brain activity and meditation
Feedback, Psychological
Cognitive Neuroscience
medicine.medical_treatment
Stimulation
Somatosensory system
Evoked Potentials, Somatosensory
medicine
Humans
Spinal Cord Injuries
Paraplegia
medicine.diagnostic_test
Brain
Magnetoencephalography
Extremities
Somatosensory Cortex
Anatomy
Middle Aged
Wrist
medicine.disease
Magnetic Resonance Imaging
Central sulcus
Electric Stimulation
Transcranial magnetic stimulation
Neurology
Somatosensory evoked potential
Female
Ankle
Psychology
Neuroscience
Algorithms
Subjects
Details
- ISSN :
- 10538119
- Volume :
- 16
- Database :
- OpenAIRE
- Journal :
- NeuroImage
- Accession number :
- edsair.doi.dedup.....76f28bb267b1d44946e244eeda687207