Questions regarding the sequential neural generator theory of the somatosensory evoked potential raised by digital filtering

doi:10.1016/0168-5597(84)90040-6

Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section

Volume 59, Issue 5, September 1984, Pages 388-395

https://doi.org/10.1016/0168-5597(84)90040-6 Get rights and content

Abstract

Digital bandpass filtering (300–2500 Hz) designed for zero phase shift was applied to somatosensory evoked potentials recorded with cephalic bipolar montages. Four consistent negative and corresponding positive peaks with latencies of about 16, 18, 19, and 20 msec were elicited with median nerve stimulation. Peroneal nerve stimulation also elicited 4 reproducible negative-positive peaks having latencies of about 24, 26, 28, and 30 msec. Interpeak latencies measured 1.3 ± 0.2 msec and 1.8 ± 0.25 msec for median and peroneal elicited SEPs respectively. Becaise cephalic bipolar recordings cancel most far-field potentials, multiple generators cannot account for all the additional components seen. It is hypothesized that some of the high frequency components recorded are due to activity in recurrent intrathalamic neuronal networks.

Résumé

Un filtre digital passe-bande (300–2500 Hz) conçu pour une différence de phase nulle a été appliqué aux potentiels évoqués somatosensoriels enregistrés en montages bipolaires céphaliques. Quatre pics négatifs reproductibles et les pics positifs correspondants, d'une latence de 16, 18, 19 et 20 msec ont été produits par stimulation du nerf médian. La stimulation du nerf péronier a également produit régulièrement 4 pics négatifs-positifs à des latences d'environ 24, 26, 28 et 30 msec. Les latences interpics étaient de 1,3 ± 0,2 msec et 1,8 ± 0,25 msec pour les PES produits par stimulation médiane et péronière respectivement. Les enregistrements céphaliques bipolaires annulant la plupart des potentiels de champs lointains, l'existence de générateurs multiples ne peut pas rendre compte de toutes les composantes additionnelles observées. L'hypothèse est faite que certaines des composantes à fréquence élevée enregistrées sont dues à l'activité de réseaux neuronaux récurrents intrathalamiques.

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^☆: This work was supported in part by a grant from the Multiple Sclerosis Society of Canada and NSERC Grant No. A4924.

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Questions regarding the sequential neural generator theory of the somatosensory evoked potential raised by digital filteringQuestions concernant la théorie du générateur nerveux séquentiel du potentiel évoqué somatosensoriel, soulevées par le filtrage digital☆

Abstract

Résumé

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

New subcortical components of the cerebral somatosensory evoked potential in man

Acta neurol. scand.

Somatosensory evoked potentials recorded directly from human thalamus and SMI cortical area

Arch. Neurol. (Chic.)