Further evidence for a distinctive atypical degenerative parkinsonism in the Caribbean: A new cluster in the French West Indian Island of Martinique.

Background: A high prevalence of an atypical levodopa-resistant parkinsonism has been reported in the Caribbean island of Guadeloupe. These seminal observations have not been replicated or extended to neighbouring populations who share genetic and environmental characteristics.

Methods: To further characterise this atypical parkinsonism we prospectively investigated 305 consecutive patients with neurodegenerative parkinsonism in a community-based population from Guadeloupe and Martinique, a neighbouring French Caribbean island where the population has similar environmental and genetic backgrounds.

Effects of afferent stimulation rate on inhibitory spinal pathways in hemiplegic spastic patients.

Objective: It has recently been demonstrated in the cat and in healthy subjects that the effects of repetitive afferent fibre stimulation depends on the target spinal neurones. The purpose of this series of experiments was therefore to determine whether central nervous system lesions modify the behaviour of the inhibitory spinal pathways in response to repetitive activation of afferent fibres.

Methods: The H-reflex technique was used to study the effect of increasing the conditioning stimulus rate from 0.

Effects of anodal tDCS on lumbar propriospinal system in healthy subjects.

Objective: It has recently been shown that transcranial direct current stimulation (tDCS) (1) can modify lumbar spinal network excitability and (2) decreases cervical propriospinal system excitability. Thus the purpose of this series of experiments was to determine if anodal tDCS applied over the leg motor cortex area induces changes in lumbar propriospinal system excitability. To that end, the effects of anodal tDCS and sham tDCS on group I and group II propriospinal facilitation of quadriceps motoneurones were studied in healthy subjects.

Effects of anodal transcranial direct current stimulation over the leg motor area on lumbar spinal network excitability in healthy subjects.

In recent years, two techniques have become available for the non-invasive stimulation of human motor cortex: transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). The effects of TMS and tDCS when applied over motor cortex should be considered with regard not only to cortical circuits but also to spinal motor circuits. The different modes of action and specificity of TMS and tDCS suggest that their effects on spinal network excitability may be different from that in the cortex.

Transmission within several spinal pathways in adults with cerebral palsy.

Many studies have investigated the changes of spinal neuronal networks in patients with cortico-subcortical or spinal lesions occurring during adulthood. In contrast, little is known about modifications of transmission within spinal networks implied in motor control for patients suffering from perinatal lesions. In the present series of experiments, we have investigated, in adult patients with cerebral palsy who suffered cerebral damage in the perinatal period, the efficacy of transmission within four spinal networks known for exhibiting pathophysiological changes following a central nervous system lesion occurring in adulthood.