The purpose of this study was to investigate the acute changes in blink reflex responses in patients with facial palsy. We used the blink reflex R2 recovery curves as an index of the excitability of the blink reflex neural circuit and evaluated the excitability of the blink reflex within 10 days after onset. Twelve patients with peripheral facial palsy were selected on condition that the degree of facial palsy was so mild that R2 responses of the blink reflex were measurable on the affected side, and they were compared with 12 healthy volunteers. Conditioning and test electrical stimuli were delivered on the affected side of the supraorbital nerve. Ipsilateral R2 response (iR2) of the blink reflex in patients was significantly enhanced at interstimulus intervals (ISIs) between conditioning and test stimuli from 100 to 1,000 ms, in comparison with the control subjects. These findings suggested hyperexcitability of the blink reflex neural circuit in patients with facial palsy. In addition to iR2, contralateral R2 response (cR2) in the patients was also significantly increased at ISIs of 100–1,000 ms to the same extent as the enhancement of iR2. All these findings suggested that the hyperexcitable changes developed in a common pathway of iR2 and cR2, but not in the ipsilateral facial motor neurons. It is suggested that the hyperexcitability of the neural circuit of the blink reflex during an acute period of facial palsy is an adaptive response to compensate for impaired facial motor function.

This content is only available via PDF.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.