IAPRD new consensus classification of myoclonus.

Introduction: Recent new advances in myoclonus characterization and etiology justify an update of the 40-year-old respected classification of myoclonus proposed by Marsden, Hallett, and Fahn. New advances include genetic studies and clinical neurophysiology characterization.

Methods: The IAPRD appointed an expert panel to develop a new myoclonus classification.

Investigation of the posterior parietal cortex to ventral premotor connection in writer's cramp using transcranial magnetic stimulation.

The posterior parietal, premotor and motor cortices are brain regions relevant in the planning of movement. Previous transcranial magnetic stimulation (TMS) studies have shown ipsilateral premotor-to-motor inhibition in healthy subjects at rest. This premotor-to-motor inhibition has been found to be altered in patients with writer's cramp (WC), a common type of focal hand dystonia.

Focal Leg Dystonia Associated with Cerebellar Infarction and Application of Low-Frequency Cerebellar Transcranial Magnetic Stimulation: Evidence of Topographically Specific Cerebellar Contribution to Dystonia Development.

The cerebellum has recently been highlighted as a key neural substrate responsible for dystonia. A 57-year-old female presented with isolated focal leg dystonia that developed 8 years after acute cerebellar infarction. Brain magnetic resonance imaging showed an old cerebellar infarct in the right anterior cerebellum.

Consensus Paper: Experimental Neurostimulation of the Cerebellum.

The cerebellum is best known for its role in controlling motor behaviors. However, recent work supports the view that it also influences non-motor behaviors. The contribution of the cerebellum towards different brain functions is underscored by its involvement in a diverse and increasing number of neurological and neuropsychiatric conditions including ataxia, dystonia, essential tremor, Parkinson's disease (PD), epilepsy, stroke, multiple sclerosis, autism spectrum disorders, dyslexia, attention deficit hyperactivity disorder (ADHD), and schizophrenia.

Psychogenic parkinsonism.

Parkinsonism can be psychogenic, and psychogenic parkinsonism is about 10% of psychogenic movement disorder patients. Patients can present with any feature or combination of features of organic Parkinson's disease. There are clinical clues that can lead to the correct diagnosis, and laboratory testing with clinical neurophysiology or DAT (dopamine transporter) scanning can be helpful as well.

Neurophysiology of dystonia: The role of inhibition.

The pathophysiology of dystonia has been best studied in patients with focal hand dystonia. A loss of inhibitory function has been demonstrated at spinal, brainstem and cortical levels. Many cortical circuits seem to be involved.

Treatment of focal dystonias with botulinum neurotoxin.

This is a review on the use of injections of botulinum toxin for the treatment of focal dystonias. Disorders covered include cranial dystonia, cervical dystonia, spasmodic dysphonia, and focal hand dystonia. Considered are clinical aspects, alternative treatment strategies and principles of use of botulinum toxin injections.

Safety study of high-frequency transcranial magnetic stimulation in patients with chronic stroke.

Objective: Repetitive transcranial magnetic stimulation (rTMS) is a potential therapeutic tool to rehabilitate chronic stroke patients. In this study, the safety of high-frequency rTMS in stroke was investigated (Phase I).

Methods: The safety of 20 and 25 Hz rTMS over the motor cortex (MC) of the affected hemisphere, with intensities of 110-130% of the motor threshold (MT), was evaluated using surface electromyography (EMG) of hand and arm muscles.

Volitional control of movement: the physiology of free will.

This review deals with the physiology of the initiation of a voluntary movement and the appreciation of whether it is voluntary or not. I argue that free will is not a driving force for movement, but a conscious awareness concerning the nature of the movement. Movement initiation and the perception of willing the movement can be separately manipulated.