- Email: [email protected]
Western society of electroencephalography
472
SOCIETY P R O C E E D I N G S
0.2 V/ram. Above the threshold, respiratory rate increased to double its unstimulated value; lactic acid formation to three times, while creatine phosphate fell to a quarter of its initial level, Respiratory response in vitro required specific substrates and particular types of impulses. I t was affected by changes in glucose level and in ionic composition of the medium supplied to the tissue, Several added substances, including general depressants and anticonvulsants inhibited certain of tissue's metabolic responses. These changes were described and compared with effects of such agents on cerebral functioning and on the electroencephalogram in viva. Some electrographic changes induced in the narcotised cat by injection of succlnate. ~ G. W . CAMnRXDG~, Leeds and B. D. WYKE, Royal College of Surgeons, London. B a r b i t u r a t e anaesthesia has been maintained in cats by intravenous injection of appropriate amounts and concentrations of drug during electrographic monitoring, as described in an earlier communication. A t various stages of narcosis, solutions of sodium suecinate in various concentrations have been injected into the femoral vein or into the carotid artery. The effects of these injections have been studied in terms of the changes in eerebral electrical activity and in somatic reflexes, on respiration, and on cerebral electrical excitability. Control experiments were also made with solutions of sodium chloride and glucose iso-osmotic with the suecinate solution, and with isomolar solutions of organic acids ofher than succinate. All solutions were adjusted to pH 7.4. At the present time our results lead us to eonclude t h a t suceinate injected during b a r b i t u r a t e anaesthesia is capable of antagonising the action of the barbiturate, and t h a t this antagonism is produced whether the succinate be injected intravenously or into the carotid artery. For we find t h a t injeetion of succinate changes the pattern of spontaneous cerebral electrical activity in such a way as to sugg e s t a temporary decrease in the narcotic effect of the barbiturate. I t also changes the p a t t e r n of somatic reflexes and the rate, pattern and minute volume of respiration, and increases the excitability of the cortex as assessed by muscular responses to electrical stimulation of the brain, in directions which suggest a decrease of narcotic effect, B u t all these changes are transient, lasting only a few minutes; and provision of increasing quantities 7.
WESTERN
SOCIETY
OF
of succlnate beyond a certain amount does not appear to increase the duration of the effect to any extent. As yet we have no information as to the precise biochemical mechanisms by which these changes are brought about. The purpose of this communieatlen is merely to indicate that injection of suecinate does produce transient alterations in the nervous system during b a r b i t u r a t e narcosis, alterations which are manifest in several spheres of central nervous activity; and t h a t these changes are specific for succinate. However, our findings do not suggest the clinical application of suecinate in eases of b a r b i t u r a t e anaesthesia or intoxication, for its effects are too brief to be of practical value. I n any case, it is most effective where an analeptic is needed least in practice - - i.e. at the lighter levels of narcosis.
8.
An investigation of catatonic schizophrenia by the photo-Metrazol activation method, m J. Hombre a n d D. M. L~BERMAN, M a u d s l e y Hos. pital, L o n d o n .
Among the various chemical methods used for the activation of the EEG Cardiazol (Metrazol) occupies a prominent place. The main weakness of using this substance is that its action is very widespread both within the central nervous system and on other structures. Therefore in the absence of precise knowledge of the physiological mechanisms of its action conclusions can only be tentative. On the other hand, it has been used more than any other substance in the various EEG laboratories and this has led to the production of a number of working hypotheses. For example Gastaut suggested t h a t combining the Metrazol method with Grey W a l t e r ' s photic stimulation would reveal functional disturbances in mid-brain structures. The authors have investigated over a hundred neuro-psychiatric patients with the Gastaut method and have confirmed t h a t idiopathic epileptics and catatonic schizophrenics have low mean thresholds, as compared with normals or other diagnostic groups. Consideration of the relationship between epilepsy and schizophrenia led to further investigations, among others of the variation in the photo-Metrazol threshold in the course of the illness of catatonic schizophrenic patients. The threshold was found to vary with the phases of the illness. These findinffs would seem to support the concept of a dieneephalie re,ulating mechanism put forward by GeIlhorn, Hill and others.
ELECTROENCEPHALOGRAPHY
Hotel Statler, Los Angeles, Calif.
May 8 and 9, 1953 Officers for 1953 : President : E U G E N E W E B B , San Francisco, Calif. Vice-President : H. W. MAGOUN, Los Angeles, Calif. Secretary-Treasurer: S. N. B E R E N S , 902 Boren Avenue, Seattle 4, Wash.
1. Relation between the caudate nucleus and the diffuse thalamic projection system, m M. VERZEANO a n d T. SmMAMOTO. School of Med-
icine, University of California at Los Angeles, and the Veterans Administration Hospital, Long Beach, Calif.
SOCIETY PROCEEDINGS Study of alterations in electrical activity of the forebrain upon stimulating the head of the eaudato nucleus in cats, has revealed m a j o r projections to lower extrapyramidal stations and to the diffuse thalamic projection system. With regard to the latter, upon caudate stimulation, burst tripping with single shocks and driving or desynchronization with low or high frequency repetitive stimuli, could be recorded from the diffusely projecting thalamic nuclei and cortical regions with which they are connected. These findings indicate the importance of connections between basal ganglia and thalamus and suggest t h a t the former may participate in cerebral functions other than motor, 2.
Changes in h i p p o c a m p a l electrical activity induced by afferent stimulation. ~ A. a n d M . G . ARDUrNI a n d J. D. GREF.~, D e p a r t m e n t of A n a . tomy, Sch. of Med., U C L A , a n d V A Hospital, Long Beach, Calif.
Alterations in the electrical activity of the hippocampus have been evoked by physiological stimulation of somatic, auditory, visual and olfactory receptors in the curarised rabbit, cat and monkey, without central anesthesia. The response invariably consisted of a train of large slow waves ( 3 - 6 / s e e . ) , often preceded by a sharp spike. This was always easily seen in the r a b b i t and with more difficulty in the cat and monkey. Such wave trains in the hippocampus were also induced by stimulation of the reticular activating system (100/see. 1 - 3 V ) in the brain stem. Findings suggest t h a t they are initiated by incoming connections from the septal region. The marked synchronization of hippocampal electrical activity induced by arousin~ stimuli contrasts strikingly with the desynchronized arous,~l pattern encountered in the electrical record of the neo-cortex, and of the two, the hippocampus seems the more easily affected, 3.
Effect of photic stimulation in visual pathways of the cat. m DONALD B. LINDSLEY, University of California, Los Angeles, Calif. Electrical responses were recorded simultaneously from several sites in the visual pathways and cortienl areas in the cat during repetitive photic stimulation. Recordin~ sites include retina, optic tract, lateral ~eniculate body, optic radiations, visual cortex I and II. and non-visual cortex. Stimulus parameters included l i g h t / d a r k ratio, intensity, wave-length, frequency, and duration of flssh. Sub-cortical electrodes were position by Horsier-Clarke technique. Recording sites were verified by histologic study. A few of the experiments were clone under Nembutal or chloro]osane anesthesia; the majority were decerebrate preparntions without subseouent anesthesia. The results show differentiation of visual and non-visual areas cortically and subeortically. The retina, optic t r a c t and lateral ~eniculate body respond discretely with varying patterns to frequencies of stimulation up to and above 100/see. whereas specific areas of the visual cortex fail to follow the stimulus beyond about 40/see. This suggests a possible mechanism of visual fusion, Interestin~ differential effects to monochromatic light have been obtained, with maximal response to yellow and blue-green, and minimal or no response to red. Intensity, duration of flash, and light-dark
473
ratio each produced modifications in subeortieal and cortical responses. The significance o]~ the results for visual theory and for further experimentation will be discussed.
Convulsions and spreading cortical depression. ~ A. VAN HARREVELD a n d J. S. STAMM, Cali. fornia Institute of Technology, Pasadena, Calif. The spreading cortical depression in the r a b b i t has previously been found to be accompanied by a slow potential change, a wave of vasoconstriction, and a decrease in cortical oxygen tension. This suggested the hypothesis t h a t the spreading depression is produced by cortical asphyxiation. The prevention 3f vasoconstriction would consequently alter the cortical depression. Cerebral vasodilators like acetylcholine, pilocarpine, and carbon dioxide were found to replace the spreading depression with a spreading convulsive pattern of the same latent period, speed of propagation, and a similar accompanying slow potential change. I t is concluded that the stimulus sets into motion a number of propagating phenomena, one of which is a vasoconstrictor mechanism, which depresses cortical activity. Another one is a convulsion producing mechanism, which can only be observed when vasoconstriction does not occur. 4.
5.
Further studies on electrical characteristics of
some types of electrodes. ~ A. M. GRASS, B. W . EDGEaTON a n d E. R. GgAss, Boston, Mass. As indicated by the title, this work is the continuation of previous studies on this subject. This group of experiments compares the electrical properties of stainless steel needle electrodes with similar electrodes made of precious metal alloys with particular reference to low frequency response and phase shift. Both types are further compared to disc type electrodes: The importance of depth of insertion is stressed. The discussion will deal with the significance of these findings in relation to EEG recordings. 6. Transistor circuits in r,emote stimulation. MARCEL VERZEANO a n d JOt~h~ D. F a s c i a , De. p a r t m e n t of A n a t o m y , School of Medicine, U C L A , a n d D e p a r t m e n t of Investigative Med. icine. V e t e r a n s Administration Hospital, Long Beach, Calif. The great usefulness in neurophysiology, of a method of stimulating the brain of unanesthetized, unrestrained animals, has led to the development by others of remote stimulation by modulated radio frequency carriers and crystal diode receivers. The high t r a n s m i t t i n g power required, the directional eL fects, and the difficulty in determining the stimulating voltage, are all disadvantages of this method. These have, however, been overcome in the present study by the addition of miniature transistor amplifiers to the crystal detector. The receiver developed on this principle consists of a crystal diode detector followed by two stages of amplification using Raytheon CK-722 PN-P transistors in " g r o u n d e d emitter )' circuits. With such a receiver mounted on the a n i m a l ' s collar and corn nected with subcutaneous leads to a bipolar electrode implanted in the brain satisfactory stimulation has been obtained at distances from the t r a n s m i t t i n g antenna varying from 6 to 80 feet. The t r a n s m i t t e r power required varied, with the distance, from 6 to
474
SOCIETY P R O C E E D I N G S
400 watts. With further miniaturization of the ¢omponents, it may become possible to imbed the receiver subcutaneously. 7.
Altered states of consciousness. ~ KARL O. VON HAOE% Los Angeles, Calif. Neuropathologically in eases with prolonged altered states of consciousness one usually finds gross lesions in the cephalic portion of the b r a i n stem, o¢casionally in its connections. These are usually due to encephalitis, trauma, thrombosis, hemorrhage, anoxia, chronic alcoholism and embolism. The electro-eneephalogram is not specific, often shows cornplete absence of b r a i n activity or high voltage slow activity which cannot be desynehronized by a f f e r e n t stimuli. 8.
T h e sleep EEG i n enuresis. - - K ~ A. BUN~ a n d KErrH S. D r r M ~ , Long B e a c h a n d San Diego, Calif. All-night E E G recordings were performed on a preliminary series of twelve nocturnal enureties, ranging in age from five years to adulthood. Nine of these were 17 years or older. Bed-wetting was signalled through one E E G channel by an electronic device, The subjects were neurologically and urologically normal, and none had epileptic histories. I n wakefulness, drowsiness, light sleep, deep sleep, and durlug bed-wetting, the EEGs remained normal, showing no patterns even suggestive of seizure activity. The children mieturated in stages ranging from deep to very light sleep. One adult (the only subject not reaching deep sleep) wet during light sleep. Two adults wet a f t e r arousing to a drowsy state, and six wet a f t e r a full waking alpha pattern had been established for 2-14 vain. All adults initially showed a strong alpha rhythm, easily abolished by slight drowsiness. Theories of etiology of enuresis are reviewed, and the psychiatric implications of the eleetrographic finding of physiological wakefulness in the adults are discussed. Psychiatric and psycho-metric data of these cases are summarized, 9.
T h e use of p h e n u r o n e in the t r e a t m e n t of natcolevsy a n d cataplexv m A lyrellminary report, R. B. A m y , N. GoavoN a n d H. C. G u o o , San Francisco, Calif. Five patients with nareolepsy and cataplexy were treated with Phenurone 0.5 gin. four times daily over a period of one year. Of this group two have had no more eatapleetie seizures and only occasional mild eDisodes of narcolepsy. A third has shown moderate improvement. Another obtained no benefit, and the drug had to be discontinued in the f i f t h ease because of its toxle effect. 10. T h e e l e c t r o e n c e p h a l o g r a m in epilepsy, m H~NRY NLnWM&N, E l e c t r o e n c e p h a l o g r a p h y Lab. oratory, S t a n f o r d U n i v e r s i t y School of Medicine, San Francisco, Calif. A review of the literature revealed considerable divergence of opinion regarding the incidence of eleetroencephalographie abnormality in patients with convulsive disorders. F o r this reason, an analysis of our own material was undertaken. The reeort~ of 430 patients with a diagnosis of epilepsy were studled. In 122 the seizures were symptomatic, in the
remainder idiopathic, and the overall i n c i d e n ~ of abnormality was little different in the two groups. I n the whole group 64.9 per cent showed abnormal records~ while in those under 16 years of age the incidenee was 71.8 per cent. The highest incidence was in patients with age of onset of seizures between 10 and 15 years, and in those with a duration of seizures from 5 to 10 years. Of patients with clinical petit real, 76 per cent had abnormal records, but only 34.6 per cent showed petit real complexes. Lateralized or focal abnormality was three times as frequent in the symptomatic t h a n in the idiopathic group. 11. T h e relationship b e t w e e n t h e electroenceph. alogram a n d scores i n c e r t a i n R o r s c h a c h categortes. ~ LEE EDWARD TitAVXS a n d CLAYTON L. B ~ N r r r , U n i v e r s i t y o | S o u t h e r n California, Los Angeles, Calif. This study attempted to determine any possible relationships between scores in certain Rorschach categories and the occipital alpha index. Thirty-two normal adults with dominant and sub-dominant alpha rhythms (Alpha Group), and 34 normal adults with mixed and rare alpha rhythms ( B e t a Group), served as subjects. Alpha Group had significantly more whole responses ( W per cent) while Beta Group had significantly more total responses (R), unusual details plus space responses (Dd, S per cent), and color responses (sum C). Also B e t a Group had more total time (T) and a higher absolute number of W. I t may be concluded tentatively t h a t alpha individuals possess a passive-receptive manner of organizing stimuli, and reflect the constrictive work of affecfive factors upon productivity. 12. Serial EEG a n d clinical followup studies of a prolonged coma insulin reaction. ~ W . P. Fxs~n, Essondale, B.C. A case of a 42 year old paranoid schizophrenic patient is presented who developed signs and syruptoms of a diencephalic and upper brainstem disturbanee while undergoing coma insulin therapy. He remained deeply comatose for 24 hours and exhibited a marked imvalrment of his consciousness for the following 15 days. Serial E E G studies were carried out which yielded initially tracings resembling deep sleep. The gradual E E G improvement with, first, the reappearance of rhythmic 5 - 7 c/see. potentials, and finally, of alpha activity, was correlated with his clinical and psychological studies. His impaired state of general awareness, his inability to focus his attention, and his incapacity to commit to memory and recall his daily experiences, were explained by an interference with some such central integrative mechanism as has been described by Penfield. 13. T h e use of central nervous system stimulants in the diagnosis of convulsive disorders. 1 C o m m a n d e r B. I. KAH~ a n d C o m m a n d e r H . S. COLONY, Neuropsychiatric Service, U n i t e d States N a v a l Hospital, O a k l a n d , Calif. Since earliest recorded medical history, camphor has been known as a central nervous system stimulant. Recently, Metrazol, Coramine and other corn1 The opinions expressed are those of the authors and are not to be construed as official or reflecting the vtews of the Navy Department or the Naval Service at large.
SOCIETY PROCEEDINGS pounds having camphor-like action have also been used to stimulate the central nervous system and to induce convulsions in susceptible individuals. Subclinical convulsive disorders are in part diagnosed by electroencephalographic study which reveals paroxysmal dysrhythmie tracings. Metrazol in minimal amounts, short of convulsive induction would show the onset of cortical dysrhythmia establishing a diagnosis of an epileptic disorder. To verify this concept 100 tracings made from psychotics without medication, 100 psychotics to whom Metrazol were given to ascertain significance of breakdown in cortical rhythm were compared with 100 known epileptics who were also given Metrazol as an adjunct in establishing the diagnosis of a convulsive disorder, The results of such tests were sufficiently uniform
475
that while the series is admittedly small, the data appears to furnish conclusive proof Metrazol as a diagnostic tool is of tremendous importance in veritying the presence of an epileptic disorder. 14. Changes following frontal lobotomy. ~ CHAR. LES L. YEAGER, Rm•ARD D. WALTER and ALEXANDER SIMON, San Francisco, Calif. A study of 150 patients undergoing surgical lobotomy was made that included pre and post operative serial tracings. The degree and extent of slow wave activity post-operatively was found to be correlated with clinical improvement. I n contrast to some previous studies, EEG abnormality was present in approximately 80 per cent of the cases three years after lobotomy.
SOCI]~Tt~ D']~LECTROENC]~PHALOGRAPHIE
ET
DES
SCIENCES
CONNEXES DE LANGUE FRAN~AISE H~pital de La Salp~tri~re, Paris. 20 mai 1953 Secr~taire: M. B. DELL, 9 r~le Jasmin, Paris 16e. 1. Etude ~lectrographique chez ['homme et chez l'anlmal de l'origine et de la propagation des d~charges ~pileptiques ¢ temporales ~. ~ HENal GASTAUT, R. NAQU~r, R. V m o u a o v x , Mines A. ROOER et M. BADIER, MarseiUe. I. Les donn$es recueillies chez l'ho~me centernent I ' E E G et I'ECoG. Du point de rue EEG, les auteurs analysent les trac~s de 300 sujets adress~s pour ~pilepsie psycho-motrice, ayant subi au moins trois enregistrements et chez lesquels le diagnostic a 6t~ confirm6 eliniquement et ~lectriquement par 1~observation et l'enregistrement d 'au moins une crise provoqu~e par injection de Cardiazol. Ils d~erivent d'abord les d~charges inter-critiques qui ne sont observ6es que dans 91 pour cent des cas et qui n'int~ressent la r~gion temporale que dans 70 pour cent d'entre eux. Ils insistent sur le nombre, le si~ge, l'~tendue, la forme et la chronologic de ces d~charges qui sont unilat~rales ou bilat~rales (et dans ce dernier cas eontemporaines ou ind~pendantes, mais pratiquement jamais synchrones), Ils ~tudient ensuite les d~charges eritiq~es qui n'accompagnent les d~charges cliniques que dans 71 pour cent des cas et qui sont bilat~rales (53 pour cent) ou focales (18 pour cent). Ils insistent sur leur forme et leur duroc qui permettent d'individualiser plusieurs vari~t~s, Dn point de rue ECoG, 45 cas seulement ont pu ~tre retenus sur les bases suivantes: existence pr~op~ratoire de d~charges temporales inter-critiques uni ou bilat~rales; exploration ECoG complete du lobe temporal et des structures qni le flanquent en dedans (gyrus hippocampi, nncus, amygdal~, insula avec ses opercules); enregistrements post-op~ratoires renouvel~s pour appr~cler le devenir des d~charges intercritiques, A partir de ces cas, les anteurs d~taillent la topographie, la morphologie et la chronologie des d~charges ~lectri~nes corticales qu'ils eomparent aux l~sions an,~tomiques observ~es par le neuro-chirur-
gien; dans un dernier paragraphe ils envisagent l'~volution post-op~ratoire des manifestations cliniques et ~lectriques de l'~pilepsie en fonction des r~sections effectu~es. II. Les donn$es recucillies chez l'auimal, concerncnt I'EEG, I'ECoG et l'anatomie pathologique de ]2 chats: 1) ayant subi une injection sous-corticale de p'~te d'alumine, 2) ayant pr~sent~ quelques mois apr~s cette injection des crises ~pileptiques de type psycho-moteur caract~ris~es par les r~actions affectives, des ph~nom~nes moteurs d4viationnels, des r~actions v~g~tatives, des activit~s alimentaires ~ type de m~tchonnement avee salivation, des ~tats confusionnels avec ou sans automatismes, 3) ayant conserv~ leurs crises pendant six ~ douze reels, 4) ayant pr~sent~ des d4charges 41ectriques intercritiques et critiques, 57 dont les l~sions ont pu ~tre ~tudi~es dans ]e d~tail apr~s le sacrifice. L'~tude EEG et ECoG de ces animaux a montr~ que leurs d~charges pr~sentent des caract~res topographiques, morphologiques et chronologiques tr~s voisins sinon identiques ~ ceux des d~ch~rges psychomotrices humaines. I I I . Sur la base des donates pr~c~dentes, les auteurs discutent quelques points th~oriques parmi lesquels: 1) L'existence rare mais eertaine d'4pil~psies psycho-motrices sans d~charges inter-crltiques, voire m~me sans d~eharges critiques; l~existence moins rare d'~pilepsies psycho-mortices avec d~charges situ~es en dehors de la r~gion temporale. 2) L'existence d'au moins trois vari~t~s topographiques d'~pilepsie psyeho-motrice en fonction du si~ge des l~sions qui les provoquent: 1°7 eelles (de beaucoup les plus nombreuses) qui trouvent leur origine clans la vaste r~gion comportant la pointe du lobe temvoral, l'uncus, l'amygdala, ]e gyrus hippocampi, l'insula et la r~gion orbitaire post~rieure; 2 °) celles (d~j~ moins nombreuses)qui trouvent leur orlgine dans une vartie du thalamus, du sons-thalamu~ ou de l'hypothalamus; 3 °) eelles (de beauceup
SOCIETY P R O C E E D I N G S
0.2 V/ram. Above the threshold, respiratory rate increased to double its unstimulated value; lactic acid formation to three times, while creatine phosphate fell to a quarter of its initial level, Respiratory response in vitro required specific substrates and particular types of impulses. I t was affected by changes in glucose level and in ionic composition of the medium supplied to the tissue, Several added substances, including general depressants and anticonvulsants inhibited certain of tissue's metabolic responses. These changes were described and compared with effects of such agents on cerebral functioning and on the electroencephalogram in viva. Some electrographic changes induced in the narcotised cat by injection of succlnate. ~ G. W . CAMnRXDG~, Leeds and B. D. WYKE, Royal College of Surgeons, London. B a r b i t u r a t e anaesthesia has been maintained in cats by intravenous injection of appropriate amounts and concentrations of drug during electrographic monitoring, as described in an earlier communication. A t various stages of narcosis, solutions of sodium suecinate in various concentrations have been injected into the femoral vein or into the carotid artery. The effects of these injections have been studied in terms of the changes in eerebral electrical activity and in somatic reflexes, on respiration, and on cerebral electrical excitability. Control experiments were also made with solutions of sodium chloride and glucose iso-osmotic with the suecinate solution, and with isomolar solutions of organic acids ofher than succinate. All solutions were adjusted to pH 7.4. At the present time our results lead us to eonclude t h a t suceinate injected during b a r b i t u r a t e anaesthesia is capable of antagonising the action of the barbiturate, and t h a t this antagonism is produced whether the succinate be injected intravenously or into the carotid artery. For we find t h a t injeetion of succinate changes the pattern of spontaneous cerebral electrical activity in such a way as to sugg e s t a temporary decrease in the narcotic effect of the barbiturate. I t also changes the p a t t e r n of somatic reflexes and the rate, pattern and minute volume of respiration, and increases the excitability of the cortex as assessed by muscular responses to electrical stimulation of the brain, in directions which suggest a decrease of narcotic effect, B u t all these changes are transient, lasting only a few minutes; and provision of increasing quantities 7.
WESTERN
SOCIETY
OF
of succlnate beyond a certain amount does not appear to increase the duration of the effect to any extent. As yet we have no information as to the precise biochemical mechanisms by which these changes are brought about. The purpose of this communieatlen is merely to indicate that injection of suecinate does produce transient alterations in the nervous system during b a r b i t u r a t e narcosis, alterations which are manifest in several spheres of central nervous activity; and t h a t these changes are specific for succinate. However, our findings do not suggest the clinical application of suecinate in eases of b a r b i t u r a t e anaesthesia or intoxication, for its effects are too brief to be of practical value. I n any case, it is most effective where an analeptic is needed least in practice - - i.e. at the lighter levels of narcosis.
8.
An investigation of catatonic schizophrenia by the photo-Metrazol activation method, m J. Hombre a n d D. M. L~BERMAN, M a u d s l e y Hos. pital, L o n d o n .
Among the various chemical methods used for the activation of the EEG Cardiazol (Metrazol) occupies a prominent place. The main weakness of using this substance is that its action is very widespread both within the central nervous system and on other structures. Therefore in the absence of precise knowledge of the physiological mechanisms of its action conclusions can only be tentative. On the other hand, it has been used more than any other substance in the various EEG laboratories and this has led to the production of a number of working hypotheses. For example Gastaut suggested t h a t combining the Metrazol method with Grey W a l t e r ' s photic stimulation would reveal functional disturbances in mid-brain structures. The authors have investigated over a hundred neuro-psychiatric patients with the Gastaut method and have confirmed t h a t idiopathic epileptics and catatonic schizophrenics have low mean thresholds, as compared with normals or other diagnostic groups. Consideration of the relationship between epilepsy and schizophrenia led to further investigations, among others of the variation in the photo-Metrazol threshold in the course of the illness of catatonic schizophrenic patients. The threshold was found to vary with the phases of the illness. These findinffs would seem to support the concept of a dieneephalie re,ulating mechanism put forward by GeIlhorn, Hill and others.
ELECTROENCEPHALOGRAPHY
Hotel Statler, Los Angeles, Calif.
May 8 and 9, 1953 Officers for 1953 : President : E U G E N E W E B B , San Francisco, Calif. Vice-President : H. W. MAGOUN, Los Angeles, Calif. Secretary-Treasurer: S. N. B E R E N S , 902 Boren Avenue, Seattle 4, Wash.
1. Relation between the caudate nucleus and the diffuse thalamic projection system, m M. VERZEANO a n d T. SmMAMOTO. School of Med-
icine, University of California at Los Angeles, and the Veterans Administration Hospital, Long Beach, Calif.
SOCIETY PROCEEDINGS Study of alterations in electrical activity of the forebrain upon stimulating the head of the eaudato nucleus in cats, has revealed m a j o r projections to lower extrapyramidal stations and to the diffuse thalamic projection system. With regard to the latter, upon caudate stimulation, burst tripping with single shocks and driving or desynchronization with low or high frequency repetitive stimuli, could be recorded from the diffusely projecting thalamic nuclei and cortical regions with which they are connected. These findings indicate the importance of connections between basal ganglia and thalamus and suggest t h a t the former may participate in cerebral functions other than motor, 2.
Changes in h i p p o c a m p a l electrical activity induced by afferent stimulation. ~ A. a n d M . G . ARDUrNI a n d J. D. GREF.~, D e p a r t m e n t of A n a . tomy, Sch. of Med., U C L A , a n d V A Hospital, Long Beach, Calif.
Alterations in the electrical activity of the hippocampus have been evoked by physiological stimulation of somatic, auditory, visual and olfactory receptors in the curarised rabbit, cat and monkey, without central anesthesia. The response invariably consisted of a train of large slow waves ( 3 - 6 / s e e . ) , often preceded by a sharp spike. This was always easily seen in the r a b b i t and with more difficulty in the cat and monkey. Such wave trains in the hippocampus were also induced by stimulation of the reticular activating system (100/see. 1 - 3 V ) in the brain stem. Findings suggest t h a t they are initiated by incoming connections from the septal region. The marked synchronization of hippocampal electrical activity induced by arousin~ stimuli contrasts strikingly with the desynchronized arous,~l pattern encountered in the electrical record of the neo-cortex, and of the two, the hippocampus seems the more easily affected, 3.
Effect of photic stimulation in visual pathways of the cat. m DONALD B. LINDSLEY, University of California, Los Angeles, Calif. Electrical responses were recorded simultaneously from several sites in the visual pathways and cortienl areas in the cat during repetitive photic stimulation. Recordin~ sites include retina, optic tract, lateral ~eniculate body, optic radiations, visual cortex I and II. and non-visual cortex. Stimulus parameters included l i g h t / d a r k ratio, intensity, wave-length, frequency, and duration of flssh. Sub-cortical electrodes were position by Horsier-Clarke technique. Recording sites were verified by histologic study. A few of the experiments were clone under Nembutal or chloro]osane anesthesia; the majority were decerebrate preparntions without subseouent anesthesia. The results show differentiation of visual and non-visual areas cortically and subeortically. The retina, optic t r a c t and lateral ~eniculate body respond discretely with varying patterns to frequencies of stimulation up to and above 100/see. whereas specific areas of the visual cortex fail to follow the stimulus beyond about 40/see. This suggests a possible mechanism of visual fusion, Interestin~ differential effects to monochromatic light have been obtained, with maximal response to yellow and blue-green, and minimal or no response to red. Intensity, duration of flash, and light-dark
473
ratio each produced modifications in subeortieal and cortical responses. The significance o]~ the results for visual theory and for further experimentation will be discussed.
Convulsions and spreading cortical depression. ~ A. VAN HARREVELD a n d J. S. STAMM, Cali. fornia Institute of Technology, Pasadena, Calif. The spreading cortical depression in the r a b b i t has previously been found to be accompanied by a slow potential change, a wave of vasoconstriction, and a decrease in cortical oxygen tension. This suggested the hypothesis t h a t the spreading depression is produced by cortical asphyxiation. The prevention 3f vasoconstriction would consequently alter the cortical depression. Cerebral vasodilators like acetylcholine, pilocarpine, and carbon dioxide were found to replace the spreading depression with a spreading convulsive pattern of the same latent period, speed of propagation, and a similar accompanying slow potential change. I t is concluded that the stimulus sets into motion a number of propagating phenomena, one of which is a vasoconstrictor mechanism, which depresses cortical activity. Another one is a convulsion producing mechanism, which can only be observed when vasoconstriction does not occur. 4.
5.
Further studies on electrical characteristics of
some types of electrodes. ~ A. M. GRASS, B. W . EDGEaTON a n d E. R. GgAss, Boston, Mass. As indicated by the title, this work is the continuation of previous studies on this subject. This group of experiments compares the electrical properties of stainless steel needle electrodes with similar electrodes made of precious metal alloys with particular reference to low frequency response and phase shift. Both types are further compared to disc type electrodes: The importance of depth of insertion is stressed. The discussion will deal with the significance of these findings in relation to EEG recordings. 6. Transistor circuits in r,emote stimulation. MARCEL VERZEANO a n d JOt~h~ D. F a s c i a , De. p a r t m e n t of A n a t o m y , School of Medicine, U C L A , a n d D e p a r t m e n t of Investigative Med. icine. V e t e r a n s Administration Hospital, Long Beach, Calif. The great usefulness in neurophysiology, of a method of stimulating the brain of unanesthetized, unrestrained animals, has led to the development by others of remote stimulation by modulated radio frequency carriers and crystal diode receivers. The high t r a n s m i t t i n g power required, the directional eL fects, and the difficulty in determining the stimulating voltage, are all disadvantages of this method. These have, however, been overcome in the present study by the addition of miniature transistor amplifiers to the crystal detector. The receiver developed on this principle consists of a crystal diode detector followed by two stages of amplification using Raytheon CK-722 PN-P transistors in " g r o u n d e d emitter )' circuits. With such a receiver mounted on the a n i m a l ' s collar and corn nected with subcutaneous leads to a bipolar electrode implanted in the brain satisfactory stimulation has been obtained at distances from the t r a n s m i t t i n g antenna varying from 6 to 80 feet. The t r a n s m i t t e r power required varied, with the distance, from 6 to
474
SOCIETY P R O C E E D I N G S
400 watts. With further miniaturization of the ¢omponents, it may become possible to imbed the receiver subcutaneously. 7.
Altered states of consciousness. ~ KARL O. VON HAOE% Los Angeles, Calif. Neuropathologically in eases with prolonged altered states of consciousness one usually finds gross lesions in the cephalic portion of the b r a i n stem, o¢casionally in its connections. These are usually due to encephalitis, trauma, thrombosis, hemorrhage, anoxia, chronic alcoholism and embolism. The electro-eneephalogram is not specific, often shows cornplete absence of b r a i n activity or high voltage slow activity which cannot be desynehronized by a f f e r e n t stimuli. 8.
T h e sleep EEG i n enuresis. - - K ~ A. BUN~ a n d KErrH S. D r r M ~ , Long B e a c h a n d San Diego, Calif. All-night E E G recordings were performed on a preliminary series of twelve nocturnal enureties, ranging in age from five years to adulthood. Nine of these were 17 years or older. Bed-wetting was signalled through one E E G channel by an electronic device, The subjects were neurologically and urologically normal, and none had epileptic histories. I n wakefulness, drowsiness, light sleep, deep sleep, and durlug bed-wetting, the EEGs remained normal, showing no patterns even suggestive of seizure activity. The children mieturated in stages ranging from deep to very light sleep. One adult (the only subject not reaching deep sleep) wet during light sleep. Two adults wet a f t e r arousing to a drowsy state, and six wet a f t e r a full waking alpha pattern had been established for 2-14 vain. All adults initially showed a strong alpha rhythm, easily abolished by slight drowsiness. Theories of etiology of enuresis are reviewed, and the psychiatric implications of the eleetrographic finding of physiological wakefulness in the adults are discussed. Psychiatric and psycho-metric data of these cases are summarized, 9.
T h e use of p h e n u r o n e in the t r e a t m e n t of natcolevsy a n d cataplexv m A lyrellminary report, R. B. A m y , N. GoavoN a n d H. C. G u o o , San Francisco, Calif. Five patients with nareolepsy and cataplexy were treated with Phenurone 0.5 gin. four times daily over a period of one year. Of this group two have had no more eatapleetie seizures and only occasional mild eDisodes of narcolepsy. A third has shown moderate improvement. Another obtained no benefit, and the drug had to be discontinued in the f i f t h ease because of its toxle effect. 10. T h e e l e c t r o e n c e p h a l o g r a m in epilepsy, m H~NRY NLnWM&N, E l e c t r o e n c e p h a l o g r a p h y Lab. oratory, S t a n f o r d U n i v e r s i t y School of Medicine, San Francisco, Calif. A review of the literature revealed considerable divergence of opinion regarding the incidence of eleetroencephalographie abnormality in patients with convulsive disorders. F o r this reason, an analysis of our own material was undertaken. The reeort~ of 430 patients with a diagnosis of epilepsy were studled. In 122 the seizures were symptomatic, in the
remainder idiopathic, and the overall i n c i d e n ~ of abnormality was little different in the two groups. I n the whole group 64.9 per cent showed abnormal records~ while in those under 16 years of age the incidenee was 71.8 per cent. The highest incidence was in patients with age of onset of seizures between 10 and 15 years, and in those with a duration of seizures from 5 to 10 years. Of patients with clinical petit real, 76 per cent had abnormal records, but only 34.6 per cent showed petit real complexes. Lateralized or focal abnormality was three times as frequent in the symptomatic t h a n in the idiopathic group. 11. T h e relationship b e t w e e n t h e electroenceph. alogram a n d scores i n c e r t a i n R o r s c h a c h categortes. ~ LEE EDWARD TitAVXS a n d CLAYTON L. B ~ N r r r , U n i v e r s i t y o | S o u t h e r n California, Los Angeles, Calif. This study attempted to determine any possible relationships between scores in certain Rorschach categories and the occipital alpha index. Thirty-two normal adults with dominant and sub-dominant alpha rhythms (Alpha Group), and 34 normal adults with mixed and rare alpha rhythms ( B e t a Group), served as subjects. Alpha Group had significantly more whole responses ( W per cent) while Beta Group had significantly more total responses (R), unusual details plus space responses (Dd, S per cent), and color responses (sum C). Also B e t a Group had more total time (T) and a higher absolute number of W. I t may be concluded tentatively t h a t alpha individuals possess a passive-receptive manner of organizing stimuli, and reflect the constrictive work of affecfive factors upon productivity. 12. Serial EEG a n d clinical followup studies of a prolonged coma insulin reaction. ~ W . P. Fxs~n, Essondale, B.C. A case of a 42 year old paranoid schizophrenic patient is presented who developed signs and syruptoms of a diencephalic and upper brainstem disturbanee while undergoing coma insulin therapy. He remained deeply comatose for 24 hours and exhibited a marked imvalrment of his consciousness for the following 15 days. Serial E E G studies were carried out which yielded initially tracings resembling deep sleep. The gradual E E G improvement with, first, the reappearance of rhythmic 5 - 7 c/see. potentials, and finally, of alpha activity, was correlated with his clinical and psychological studies. His impaired state of general awareness, his inability to focus his attention, and his incapacity to commit to memory and recall his daily experiences, were explained by an interference with some such central integrative mechanism as has been described by Penfield. 13. T h e use of central nervous system stimulants in the diagnosis of convulsive disorders. 1 C o m m a n d e r B. I. KAH~ a n d C o m m a n d e r H . S. COLONY, Neuropsychiatric Service, U n i t e d States N a v a l Hospital, O a k l a n d , Calif. Since earliest recorded medical history, camphor has been known as a central nervous system stimulant. Recently, Metrazol, Coramine and other corn1 The opinions expressed are those of the authors and are not to be construed as official or reflecting the vtews of the Navy Department or the Naval Service at large.
SOCIETY PROCEEDINGS pounds having camphor-like action have also been used to stimulate the central nervous system and to induce convulsions in susceptible individuals. Subclinical convulsive disorders are in part diagnosed by electroencephalographic study which reveals paroxysmal dysrhythmie tracings. Metrazol in minimal amounts, short of convulsive induction would show the onset of cortical dysrhythmia establishing a diagnosis of an epileptic disorder. To verify this concept 100 tracings made from psychotics without medication, 100 psychotics to whom Metrazol were given to ascertain significance of breakdown in cortical rhythm were compared with 100 known epileptics who were also given Metrazol as an adjunct in establishing the diagnosis of a convulsive disorder, The results of such tests were sufficiently uniform
475
that while the series is admittedly small, the data appears to furnish conclusive proof Metrazol as a diagnostic tool is of tremendous importance in veritying the presence of an epileptic disorder. 14. Changes following frontal lobotomy. ~ CHAR. LES L. YEAGER, Rm•ARD D. WALTER and ALEXANDER SIMON, San Francisco, Calif. A study of 150 patients undergoing surgical lobotomy was made that included pre and post operative serial tracings. The degree and extent of slow wave activity post-operatively was found to be correlated with clinical improvement. I n contrast to some previous studies, EEG abnormality was present in approximately 80 per cent of the cases three years after lobotomy.
SOCI]~Tt~ D']~LECTROENC]~PHALOGRAPHIE
ET
DES
SCIENCES
CONNEXES DE LANGUE FRAN~AISE H~pital de La Salp~tri~re, Paris. 20 mai 1953 Secr~taire: M. B. DELL, 9 r~le Jasmin, Paris 16e. 1. Etude ~lectrographique chez ['homme et chez l'anlmal de l'origine et de la propagation des d~charges ~pileptiques ¢ temporales ~. ~ HENal GASTAUT, R. NAQU~r, R. V m o u a o v x , Mines A. ROOER et M. BADIER, MarseiUe. I. Les donn$es recueillies chez l'ho~me centernent I ' E E G et I'ECoG. Du point de rue EEG, les auteurs analysent les trac~s de 300 sujets adress~s pour ~pilepsie psycho-motrice, ayant subi au moins trois enregistrements et chez lesquels le diagnostic a 6t~ confirm6 eliniquement et ~lectriquement par 1~observation et l'enregistrement d 'au moins une crise provoqu~e par injection de Cardiazol. Ils d~erivent d'abord les d~charges inter-critiques qui ne sont observ6es que dans 91 pour cent des cas et qui n'int~ressent la r~gion temporale que dans 70 pour cent d'entre eux. Ils insistent sur le nombre, le si~ge, l'~tendue, la forme et la chronologic de ces d~charges qui sont unilat~rales ou bilat~rales (et dans ce dernier cas eontemporaines ou ind~pendantes, mais pratiquement jamais synchrones), Ils ~tudient ensuite les d~charges eritiq~es qui n'accompagnent les d~charges cliniques que dans 71 pour cent des cas et qui sont bilat~rales (53 pour cent) ou focales (18 pour cent). Ils insistent sur leur forme et leur duroc qui permettent d'individualiser plusieurs vari~t~s, Dn point de rue ECoG, 45 cas seulement ont pu ~tre retenus sur les bases suivantes: existence pr~op~ratoire de d~charges temporales inter-critiques uni ou bilat~rales; exploration ECoG complete du lobe temporal et des structures qni le flanquent en dedans (gyrus hippocampi, nncus, amygdal~, insula avec ses opercules); enregistrements post-op~ratoires renouvel~s pour appr~cler le devenir des d~charges intercritiques, A partir de ces cas, les anteurs d~taillent la topographie, la morphologie et la chronologie des d~charges ~lectri~nes corticales qu'ils eomparent aux l~sions an,~tomiques observ~es par le neuro-chirur-
gien; dans un dernier paragraphe ils envisagent l'~volution post-op~ratoire des manifestations cliniques et ~lectriques de l'~pilepsie en fonction des r~sections effectu~es. II. Les donn$es recucillies chez l'auimal, concerncnt I'EEG, I'ECoG et l'anatomie pathologique de ]2 chats: 1) ayant subi une injection sous-corticale de p'~te d'alumine, 2) ayant pr~sent~ quelques mois apr~s cette injection des crises ~pileptiques de type psycho-moteur caract~ris~es par les r~actions affectives, des ph~nom~nes moteurs d4viationnels, des r~actions v~g~tatives, des activit~s alimentaires ~ type de m~tchonnement avee salivation, des ~tats confusionnels avec ou sans automatismes, 3) ayant conserv~ leurs crises pendant six ~ douze reels, 4) ayant pr~sent~ des d4charges 41ectriques intercritiques et critiques, 57 dont les l~sions ont pu ~tre ~tudi~es dans ]e d~tail apr~s le sacrifice. L'~tude EEG et ECoG de ces animaux a montr~ que leurs d~charges pr~sentent des caract~res topographiques, morphologiques et chronologiques tr~s voisins sinon identiques ~ ceux des d~ch~rges psychomotrices humaines. I I I . Sur la base des donates pr~c~dentes, les auteurs discutent quelques points th~oriques parmi lesquels: 1) L'existence rare mais eertaine d'4pil~psies psycho-motrices sans d~charges inter-crltiques, voire m~me sans d~eharges critiques; l~existence moins rare d'~pilepsies psycho-mortices avec d~charges situ~es en dehors de la r~gion temporale. 2) L'existence d'au moins trois vari~t~s topographiques d'~pilepsie psyeho-motrice en fonction du si~ge des l~sions qui les provoquent: 1°7 eelles (de beaucoup les plus nombreuses) qui trouvent leur origine clans la vaste r~gion comportant la pointe du lobe temvoral, l'uncus, l'amygdala, ]e gyrus hippocampi, l'insula et la r~gion orbitaire post~rieure; 2 °) celles (d~j~ moins nombreuses)qui trouvent leur orlgine dans une vartie du thalamus, du sons-thalamu~ ou de l'hypothalamus; 3 °) eelles (de beauceup