Gait-related cerebral alterations in patients with Parkinson's disease with freezing of gait.

Freezing of gait is a common, debilitating feature of Parkinson's disease. We have studied gait planning in patients with freezing of gait, using motor imagery of walking in combination with functional magnetic resonance imaging. This approach exploits the large neural overlap that exists between planning and imagining a movement.

General movements in the perinatal period and its relation to echogenicity changes in the brain.

Background: In preterm born infants abnormal general movements (GMs) generally normalize before three months post term, but may persist when perinatal brain injury is present.

Aims: To assess the continuity of GM quality from fetal to early neonatal period and its relation to brain echogenicity changes.

Study Design: Prospective study examining GMs and three vulnerable brain areas before and 7days after birth.

Spatial remapping of cortico-striatal connectivity in Parkinson's disease.

Parkinson's disease (PD) is characterized by striatal dopamine depletion, especially in the posterior putamen. The dense connectivity profile of the striatum suggests that these local impairments may propagate throughout the whole cortico-striatal network. Here we test the effect of striatal dopamine depletion on cortico-striatal network properties by comparing the functional connectivity profile of the posterior putamen, the anterior putamen, and the caudate nucleus between 41 PD patients and 36 matched controls.

Clinimetrics of freezing of gait.

The clinical assessment of freezing of gait (FOG) provides great challenges. Patients often do not realize what FOG really is. Assessing FOG is further complicated by the episodic, unpredictable, and variable presentation, as well as the complex relationship with medication.

Postural responses to multidirectional stance perturbations in cerebellar ataxia.

Previous studies of patients with focal cerebellar damage underscored the importance of the cerebellum for balance control. These studies were restricted to postural control in the pitch plane, and focused mainly on leg muscle responses. Here, we examined the effect of degenerative cerebellar lesions on postural control in multiple directions, and studied how such lesions affect intersegmental coordination of the legs, trunk and arms.

Repetitive transcranial magnetic stimulation to improve mood and motor function in Parkinson's disease.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that can produce lasting changes in excitability and activity in cortical regions underneath the stimulation coil (local effect), but also within functionally connected cortical or subcortical regions (remote effects). Since the clinical presentation of Parkinson's disease (PD) is related to abnormal neuronal activity within the basal ganglia and cortical regions, including the primary motor cortex, the premotor cortex and the prefrontal cortex, several studies have used rTMS to improve brain function in PD. Here, we review the studies that have investigated the possible therapeutic effects of rTMS on mood and motor function in PD patients.

Trunk sway in patients with spinocerebellar ataxia.

We investigated whether quantified measurements of trunk sway during stance and gait tests in patients with autosomal dominant spinocerebellar ataxia (SCA) could be a useful approach to assess ataxia, which is highly relevant for adequate follow-up and future intervention studies. Examined were 11 SCA patients and 11 age-matched, healthy controls. Postural and balance control were quantified using peak-to-peak measurements of trunk angle and angular velocity, in the roll (lateral) and pitch (anterior-posterior) directions, during a battery of stance and gait tasks.

Effects of stimulation pattern on electrical stimulation-induced leg cycling performance.

Electrical stimulation-induced leg cycling (ES-LC) is beneficial for individuals with spinal cord injury (SCI), but cycling performance is often limited because of rapid fatigue of the stimulated muscles. This study evaluated whether a stimulation pattern with a catchlike-inducing pulse train increased force production and hence cycling performance. Five men with SCI performed ES-LC using different stimulation patterns: (1) the standard pattern with ramp modulation, (2) a pattern with no ramp modulation, (3) a pattern with no ramp modulation but with an initial doublet, and (4) a pattern with a middle doublet.

Effects of stereotactic neurosurgery on postural instability and gait in Parkinson's disease.

Postural instability and gait disability (PIGD) are disabling signs of Parkinson's disease. Stereotactic surgery aimed at the internal globus pallidus (GPi) or subthalamic nucleus (STN) might improve PIGD, but the precise effects remain unclear. We performed a systematic review of studies that examined the effects of GPi or STN surgery on PIGD.