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Beta activity as an electrical seizure phenomena
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Type I pattern of inmediate diffuse barbiturate induced medium voltage beta rhythm; Type II pattern of medium-high voltage arrhythmic theta activity superimposed on beta rhythm; Type III pattern of high voltage rhythmic and semirhythmic sharp and slow (delta and theta) activity (most prominent in the nasopharyngeal and temporal leads). The normal Type I pattern was found in 25% of the alcoholics studied, while an abnormal Type II or Type III pattern was found in 75% of the alcoholics studied. The type II and Type III responses may be explained bv a relative loss of the ability of the cortex to respond with immediate beta rhythm. This would be consistent with the finding of significant cortical atrophy in a high percentage of chronic alcoholics. Alternatively, methohexital may produce the abnormal Type II and Type III responses by inhibiting cortical structures preferentially, allowing abnormal limbic or other subcortical areas to discharge excessively. D-1.04 EFFECTS OF LITHIUM ON CLINICAL AND EXPERIMENTAL MYOTONIA. R.A. Brumback, J.W. Gerst and R.D. Staton (Fargo, N. Dak., USA) Myotonia is delayed relaxation of muscle fibers after contraction, associated with normal initial muscle fiber ootentials. followed bv distinctive after-discharges of-repetitive potentials of increasing and decreasing frequency, recorded by EMG as waxing-and-waning "divebomber" discharges. Weanling Wistar rats, made myotonic by nine oral doses of 150 mg/ko of 20, 25-diazacholesterol over 3 weeks, walked stifflv. had mvotonic discharqes on EMG. and showed deiayed muscle relaxation: Lithium-chloride (0.6% solution) was given intravenously to the
animals during recording of tibialis anterior muscle twitch. After lithium administration there was a 50% improvement in muscle twitch tension and a normal relaxation time. A 37-
year-old man with myotonia congenita experienced marked stiffness with movement and had typical clinical and EMG myotonia. Treatment with phenytoin, quinine, and procainamide produced unpleasant side-effects and no improveLithium carbonate was ment in the myotonia. administered until he had marked reduction in clinical myotonia, increased ability to perform activities, and reduction in recordable The blood lithium level electrical myotonia. required to achieve this marked improvement was 2.3 mEq/l, which was associated with excessive sedation but no other problematic sideeffects. Blood lithium levels less than 2.0 mEq/l produced no clinically evident beneficial Further research with effect on the myotonia. lithium may demonstrate its utility as an adjunctive treatment for patients with myotonia.
C-14.08 BETA ACTIVITY AS AN ELECTRICAL SEIZURE PHENOMENA. R.A. Brumback and R.D. Staton (Fargo, N. Dak., USA) EEG waves havinq durations of 33 to 66 msec (15 to 30 c/set) are termed "beta waves". Rhythmic beta activitv recorded in the wakins EEG of normals may be: -(I) a central rhythm selectively blocked by sensory stimulation or movement of the contralateral extremity, (2) a posterior rhythm selectively blocked by visual stimuli ("fast alpha variant"), or (3) a diffuse low-voltage rhythm not blocked by any stimulus. Various drugs produce or enhance a diffuse beta rhythm. Asymmetrical absence of beta rhythm either spontaneously or after drug administration can localize cortical lesions. In nineteen channel EEG records we found that diffuse medium voltage rhythmic activity of beta frequency is the initial electrical activity which immediately follows the delivery of an electroThis beta-like convulsive shock stimulus. rhythm (Phase I'of the ECT-induced seizure) appears bilaterally symmetrically in all leads, but is of highest voltage in the fronto-central The initial frequency of this Phase I leads. beta activity is 22 to 24 c/set, but this slows to 16 to 18 c/set before being replaced after 1 to 3 set by Phase II arrhythmic polyspikes. From our tracings beta activity appears to be a specialized form of synchronous electrical seizure activity distinct from arrhythmic spikes/polyspikes and from 2.5 to 3.5 c/set "centrenceohalic" spike-wave activity. We also have the tracing of'a spontaneous se>zure in which electrical activity in the beta frequency range predominates. A-11.01 LECTUEL
LE SOMMEIL DES SUJETS A QUOTIENT INTELH. Huon (Vannes, France) ELEVE.
Plusieurs centaines de sujets adultes appartenant a la MENSA, ayant done un quotient intellectuel suoerieur a 140, ont repondu a un questionnaire sur le sommeii. ’ Quinze d'entre eux ont ete l'objetd'une analyse polygraphique de deux nuits de sommeil. Des particularites se degagent par rapport a la population generale et semblent sigOn note en particulier un endornificatives. missement rapide, une abondance du stade 4, la bonne qualite objective et subjective du sommeil et, d'une facon generale, un ensemble d'elements qui semblent traduire un bon fonctionnement des structures du sommeil. Ces resultats seront analyses et comment&.
Type I pattern of inmediate diffuse barbiturate induced medium voltage beta rhythm; Type II pattern of medium-high voltage arrhythmic theta activity superimposed on beta rhythm; Type III pattern of high voltage rhythmic and semirhythmic sharp and slow (delta and theta) activity (most prominent in the nasopharyngeal and temporal leads). The normal Type I pattern was found in 25% of the alcoholics studied, while an abnormal Type II or Type III pattern was found in 75% of the alcoholics studied. The type II and Type III responses may be explained bv a relative loss of the ability of the cortex to respond with immediate beta rhythm. This would be consistent with the finding of significant cortical atrophy in a high percentage of chronic alcoholics. Alternatively, methohexital may produce the abnormal Type II and Type III responses by inhibiting cortical structures preferentially, allowing abnormal limbic or other subcortical areas to discharge excessively. D-1.04 EFFECTS OF LITHIUM ON CLINICAL AND EXPERIMENTAL MYOTONIA. R.A. Brumback, J.W. Gerst and R.D. Staton (Fargo, N. Dak., USA) Myotonia is delayed relaxation of muscle fibers after contraction, associated with normal initial muscle fiber ootentials. followed bv distinctive after-discharges of-repetitive potentials of increasing and decreasing frequency, recorded by EMG as waxing-and-waning "divebomber" discharges. Weanling Wistar rats, made myotonic by nine oral doses of 150 mg/ko of 20, 25-diazacholesterol over 3 weeks, walked stifflv. had mvotonic discharqes on EMG. and showed deiayed muscle relaxation: Lithium-chloride (0.6% solution) was given intravenously to the
animals during recording of tibialis anterior muscle twitch. After lithium administration there was a 50% improvement in muscle twitch tension and a normal relaxation time. A 37-
year-old man with myotonia congenita experienced marked stiffness with movement and had typical clinical and EMG myotonia. Treatment with phenytoin, quinine, and procainamide produced unpleasant side-effects and no improveLithium carbonate was ment in the myotonia. administered until he had marked reduction in clinical myotonia, increased ability to perform activities, and reduction in recordable The blood lithium level electrical myotonia. required to achieve this marked improvement was 2.3 mEq/l, which was associated with excessive sedation but no other problematic sideeffects. Blood lithium levels less than 2.0 mEq/l produced no clinically evident beneficial Further research with effect on the myotonia. lithium may demonstrate its utility as an adjunctive treatment for patients with myotonia.
C-14.08 BETA ACTIVITY AS AN ELECTRICAL SEIZURE PHENOMENA. R.A. Brumback and R.D. Staton (Fargo, N. Dak., USA) EEG waves havinq durations of 33 to 66 msec (15 to 30 c/set) are termed "beta waves". Rhythmic beta activitv recorded in the wakins EEG of normals may be: -(I) a central rhythm selectively blocked by sensory stimulation or movement of the contralateral extremity, (2) a posterior rhythm selectively blocked by visual stimuli ("fast alpha variant"), or (3) a diffuse low-voltage rhythm not blocked by any stimulus. Various drugs produce or enhance a diffuse beta rhythm. Asymmetrical absence of beta rhythm either spontaneously or after drug administration can localize cortical lesions. In nineteen channel EEG records we found that diffuse medium voltage rhythmic activity of beta frequency is the initial electrical activity which immediately follows the delivery of an electroThis beta-like convulsive shock stimulus. rhythm (Phase I'of the ECT-induced seizure) appears bilaterally symmetrically in all leads, but is of highest voltage in the fronto-central The initial frequency of this Phase I leads. beta activity is 22 to 24 c/set, but this slows to 16 to 18 c/set before being replaced after 1 to 3 set by Phase II arrhythmic polyspikes. From our tracings beta activity appears to be a specialized form of synchronous electrical seizure activity distinct from arrhythmic spikes/polyspikes and from 2.5 to 3.5 c/set "centrenceohalic" spike-wave activity. We also have the tracing of'a spontaneous se>zure in which electrical activity in the beta frequency range predominates. A-11.01 LECTUEL
LE SOMMEIL DES SUJETS A QUOTIENT INTELH. Huon (Vannes, France) ELEVE.
Plusieurs centaines de sujets adultes appartenant a la MENSA, ayant done un quotient intellectuel suoerieur a 140, ont repondu a un questionnaire sur le sommeii. ’ Quinze d'entre eux ont ete l'objetd'une analyse polygraphique de deux nuits de sommeil. Des particularites se degagent par rapport a la population generale et semblent sigOn note en particulier un endornificatives. missement rapide, une abondance du stade 4, la bonne qualite objective et subjective du sommeil et, d'une facon generale, un ensemble d'elements qui semblent traduire un bon fonctionnement des structures du sommeil. Ces resultats seront analyses et comment&.