Intracranial stimulation of the trigeminal nerve in man. II. Reflex responses.
AUTOR(ES)
Cruccu, G
RESUMO
The reflex responses evoked by direct electrical stimulation of the intracranial portion of the trigeminal nerve have been studied in 16 subjects undergoing percutaneous retrogasserian thermocoagulation for the treatment of trigeminal neuralgia affecting the second or third division. In the obicularis oculi muscle, early and late responses similar to the R1 and R2 components of the blink reflex were recorded. The former could be evoked only by stimulation of the second division and its latency was consistent with intermediately fast afferents. A late reflex (50-70 ms) was occasionally recorded from the anterior belly of the digastric muscle. The response was sometimes followed by a later activity and showed the features of a polysynaptic reflex. No response was obtained in the jaw elevators when fully relaxed. With the subject voluntarily clenching his teeth, both an early "H-like" response and two silent periods in the background EMG were obtained. The second silent period was similar in the muscles ipsi- and contralateral to intracranial stimulation, while the first silent period was longer in the ipsilateral muscles. Possible mechanisms contributing to the inhibition following stimulation of the mixed portion of the nerve are discussed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1028769Documentos Relacionados
- Intracranial stimulation of the trigeminal nerve in man. I. Direct motor responses.
- Intracranial stimulation of the trigeminal nerve in man. III. Sensory potentials.
- Evoked skin sympathetic nerve responses in man.
- The Role of Endotoxin during Typhoid Fever and Tularemia in Man. II. Altered Cardiovascular Responses to Catecholamines*
- Characterisation of textile dust extracts: II. Bronchoconstriction in man.