- Email: [email protected]
Eastern association of electroencephalographers
ITALIAN .~d3CIETY GS responses are observable at every hypnotic test. No diminution of the EEG response to train stimuli has been observed during the hypnotic anesthesia test. (5) Some patterns, as inversion of the alpha blocking reaction, have been observed sometimes in advanced phases of the hypnotic procedure, which hint at a state of exhaustion or fatigue. Periods of flattening of thc EEG, which not infrequently occur, do not seem to correspond to early phases
~21
of sleep, since the simultaneous GSR variations reveal a heightening of the activation level, that is, it shows that the subject is more amused, Finally the authors agree that hypnosis is not a special state which a subject "goes into", "comes out of" (T.X. Batt)er), but a behaviour in wh/ch an active attitude of the subject, and the transactional process between the subject and the hypnotist, play an important role.
Electroenceph. clin. Neurophy$iol., 1963, 15:916-921
EASTERN ASSOCIATION OF ELECTROENCEPHALOGRAPHERS New York, N.Y., December 5, 1962
Secretary: DR. J. R. HUGHES 462 Grlder St,, BuB'alo, N.Y. (U.S.A.)
I. Paroxysmal bllndneu.--H, Strauss (New York, N.Y.). This boy, 11 years old, has suffered from attacks of complete blindness with preservation of consciousness, lasting between 2 and 10 rain. The EEG shows almost continuous spike and wave patterns with frequencies from 1.5 to 3 per ~ , sometimes with double spikes, at the occipital electrodes, often simultaneously at the posterior temporal and, more rarely, the parietal electrodes, with a voltabe up to 200 pV. The number of these bursts decream with opening of the eyes, flicker with frequencies of 4 or more per sec and hyperventiiation, Mental activity has no in. fluenos, Neurological examination, including visual fields, optokinetic nystqmus was entlre!y neptive. Contrary to those cases with ictal blindness, in which the d i g h a r p started from one occipital region, one is dealing here with a osntrenosphalic disturbance, affecting maximally the o~ipital region. No similar case seems to have been pub. lished. The abnormal EEG and all clinical phenomena were promptly controlled by a combination of Tridione and Dilantin. 2 . - c . m t m e e p m u e ' eh~~emk~rsphk m u m . in ~ idmr~y, - - R, G. ~ md K. Abm-
hm (Bema~ Md.), Four cases of true precocious puberty associated with an EEG patten, sugBestive of "osntrenosphalic" origin (23.5/see bilateral and relatively synchronous and symmetrical spike and wave complexes) are presented, and three similar casesare r e p o ~ from the literature. Three of the present four cases exhibited clinical-radiological ~..idence indicative of precocious puberty of the "cerebral" type with probable lesions in the area of the hypothalamus and 3rd ventricle. An analysis of these cases suggests flint bilateral spike and wave discharges, often associated with seizures, may be a not uncommon finding in precocious
puberty of the cerebral type, and that these EEG patterns may occur with structural lesions in these areas even in the absence of other neurologic manifestations. The clinical-pathological and experimental evidence in support of the hypothetical "centrencephalon" of Penfield and Jasper as the site of origin of the 3/see spike and wave complex still remains rather controversial. However, the occurrence of this EEG pattern in association with a syndrome accompanied by organic lesions in those subcortical regions likely included in the ill.defined and hylmthetical "osntrencephalic" center, lends clinical support to the role of these regions in the patho.physiologlcal mechanisms of these EEG patterns. (Full paper in press in Elect~e,¢eph. olin. Neurophyslol., 1953). 3. Sleep BEGs in a IMe-tm-Me, ~ type of ~,oner pelmlm/on. - - W. J. (Allmm.. N.Y.). The recent EEG literature contains numerous references to the association between 14 and 7 per sec Ix~iiti~ spikes and behavior disorders with only an occasional report of negative findings. In the last year, sleep EEGs were ob. rained on 20 inmates of the New York State Vocational Institute who ranged in age from 16 to 20 years; they were all assigned to a special project to evaluate the care of younf epileptics in a penal institution. In most cases, their seizures were atypical and, indeed, in several it was felt that they did not suffer from epilepsy at 411.All were serving sentences for crimes that could not~reasonablyroe directly due to their epilepsy; none of them were institutionalized for a single crime and none had an I.Q. below borderline normal. Based on the literature, it was expected that there would be a relatively high incidence of"14 and 7" but in no case was such an electrographic configuration seen. The sleep EEGs of 27 other patients in the same abe group done over the same period of time were reviewed; in most of these casessleep EEGs were indicated because
Electrofnceph.din. Neurophysiol.,1963, 13:921-925
922
S4X'IETY PROCEEDINGS
of a possible diagnosis of epilepsy; five of this "control" group had "14 and 7". The possible reasons for these findings in the prisoners will be discussed. 4t. EEG in myotoain dystrophlea. - - J. Biltenbender and W. F ~ ( ~ Pa. and Albany, N.Y.). Myotonia dystrophica is a disease which involves a number of different bodily systems. However, in spite of repeated references to behavioral and intellectual abnormalities and pneumoencephalographic evidence of brain atrophy, there has been no evaluation of cerebral function as measured by EEG except in a few isolated case reports. The EEGs of 23 adult patients suffering from myotonia dystrophica were obtained. All had EEGs which were within the range of normal except for four who varied from the usual criteria of normal by having an "alpha" rate of less than 8/see. Even independent of these four patients, the myotonic patients as a group had a slower average alpha rate than an aged.matched control group. The basis for this EEG finding in myotonic patients cannot be definitely ascertained from our series but the suggestion can bc offered that this is at least in part a reflection of their not infrequent mild hypothyroidism.
5. Eleetro~eeplmle~zphic, eeflleogmphle and intraeerebral potentbds in two anatomically verified cases of Creutdeldt-.]laeob Disease. - - M. Raype.t (NewYork, N.Y,).
Electrophysiological observations have been made on two cases of Creutzfeldt.Jacob (CJ) disea,se under a combined program of neurochemical, ultrastructural and electro. graphic investigations of degenerative disease,s of the brain (Korey et oL, American Academy t~f Neurology,
196~), The histological diagnosis in these two cases is based on brain biopsy specimens and autopsy material, At the cortical recording site, as well as elsewhere in the cortex, there was mild to marked loss of cortical neurones and alteration of the staining characteristics of many of the remaining ganglion cells, Sharply demarcated"microcysts" and swollen Mtrocytes were present in the neuropil, Neuro6brillary tangles and senile plaques were absent. The histologtc picture was considered to be consistent with CJ disease (R. D. Terry). Scalp ele~roencephalolFams were characterized by periodic bursts of high voltage positive-negative spikes and triophasic potentials recurring continuously at inter. pals ranging from 0.5 to 2 sac (Heeler, Lesse and Austin 1958; Alem~, Vizioli and Reda 1959), In the electrocorti. cobras taken during craniotomy similar complexes were recorded from the plal surface of the second right frontal convolution. Complete neuronal isolation of a portion (2.5 × 2 cm) of this ~ r u s resulted in very marked amplitude attenuation of these discharges, Amplitude attenuation of minor extent was observed when one of the pial recording ~ele~rodes was moved from cortex to white matter exposed by cortical biopsy. Intracerebral record. in8 with depth electrodes revealed the periodic complexes to be siwpler and of low amplitude in the white matter.
However, high voltage tri-phasic complexes resembling those recorded from the scalp znd the pial surface were again encountered in the subcortical grey matter (globus pallidus). These findings indicate two separate loci for the generation of the periodic bursts. The relationship of the subcortical and cortical activity to each other and to the scalp electroencephalogram will be discussed. 6. Evoked visual cortical responses in homonymous hemianopic defects in man. --- R. Cohn ~ M&). By the use of linear summating techniques (Mnemotron CAT) it is observed that 50 to 230 trains of photic stimulation, of variable frequency, generate essentially equal amplitude potentials from the occipital regions in nearly all normal individuals. Using similar derivatioqs (electrode arrays) it has been observed that with approxtmately 3 to 10 per sec stimulation there is a prominent amplitude asymmetry in the occipital outputs in all patients studied who clinically demonstrated lateral homonymous hemianopic defects. in some patients the lower amplitude potentials evoked from the involved side showed only a second harmonic output. These findings appear more reproducible than the changes observed, under similar conditions, using a stimulus pulse cycle of around I per sac. 7. A ,ew audio mote' system In man. - - R. G. Bitkfe.d, J, L. Jaeeblen and R.F. Galbralth 0tedmter, Minn.).
(n the course of observations using a CAT average response computer, an audio motor response system has been discovered, When click stimuli having intensities of I00~135 Db. (750 cycles basic frequency damped o~illa. lion) are applied to the ear in normal human subjects, a widespread response can be detected in facial, cranial and limb musculature. This can be clearly seen in averages of 100~150 responses when its amplitude may range from 10ol00 I,V. The latency is remarkably short in the cervical muscles (8-10 reset) indicating a simple two or three neurone-are pathway through the brainatem. The ampli. tude of the response is related to tension in the muscles and it disappears on complete relaxation. It is buried in voluntary EMG activity and usually cannot be seen in the un. processed raw data. Experiments, including curarization and manipulation of mu~le tension, indicate that while the response is myogenic in origin, it is capable of subtle imitation of genuine cortical evoked potentials, This fast audio motor response can be separated by latency from other known motor systems, For instance, the latency in the cervical muscles recorded inthe neck, is 8-10 msec for the fast response, 25 re.see for I "startle" response to a pistol shot and 100 msec for a voluntary movement response to an auditory stimulus. The function of this fast system is presently unknown, but its peg. sible implication in the pmma efferent system is being explored, It appears that "downstream" or centrifugal averaging in which probabilistic events in the contracted muscle mirror central processes may have wide application in neurologic research. ($upporledbyUSPHS(Tront B2056).
Electroencepb.din Neuropkysio/.,1963, I$: 921-925
EASTERN ASSOCIATIONOF ELECTROENCEPHALOGRAPHERS g. A factor ~amlyticshMy of ciinieal and electroeacephaiographic variables in epileptic patients. - - E, A. Rodin sad Y. L~ (Detroit, Mich.). Fifty-seven epileptic patients were investigated in detail from the clinical, neurological, psychiatric, psychologic, and electroencephalographic point of view. A seizure was induced by Mcgimide administration in all patients and the attack was pho~-~,~hed. The results of the investigations were coded in detail to allow automatic data processing. 155 variables were then selected for inter-correlations and 1,089 statistically significant correlations were obtained. Eighty variables which had shown the highest correlation coefficients were subsequently chosen for factor analysis. By means of the principal axes method and varimax rotation, eleven factors were extracted and identified. In view of time considerations the discussion will be limited to the presentation of three factors. The first factor deals with severity of seizure disorders, diffuse brain damage, and slowing of the background rhythms in the electroencephalogram. It contrasts differentiating features between the "deteriorated" epileptic and the patient with a seizure disorder but a normal mentality. The second factor shows differences between centrencephalic and focal cortical seizure disorders. Sociopathic behavior, behavioral difficulties in school, and difficulty concentrating were found to be related to the centrencephalic group which was abe younger in age. The third factor to be discussed deals with aspects of those patients whose induced Grand Mal seizure started with a gradual build-up of discharges in the left temporal area and pointed out, in addition to certain clinical features of the attack pattern, the importance of the post-ictal clinical phenomena in assessing the locus of origin of the epileptic discharge. In view of the fact that the number of patients investi. gated was still relatively small the study will be repeated on another sample.
9. Cliniadepllepflformselzuresorlainaflnslnchronle partially imlated e e r d n l cortex. - - F. A, Fa~tlln and k. Batters (New York, N.Y.). Further evidence is presented that rhythmic stimulation of a peripheral nerve will precipitate epik~tiform electrical activity selectively from an area of co:~nic, partially neuronally isolated, frontal cerebral cortex. In some animals this local epileptiform discharge spread ~md caused a generalized clinical seizure. tO. Effects of dilantin on focal eplleptoganle activity of cat neocortex. - - F. S. MusErsve u d D. P. Parpam (New York, N.Y.). The magnitude and duration of injury pot~tials, discharge frequency and characteristics of secondary homolateral and contralaterai projection activity have been studied in control and dilantin-treated cats following production of standard 4 mm-diameter cold lesions of suprasylvian cyrus. Treated animals received approximately 10 mg/kg/ day i.m. dilantin for 2 weeks or more prior to production
923
of freezing lesions. Negative injury potentials generated at the lesion site were significantly smaller in amplitude and shorter in duration in dilantin-treated animals than in controls. Dilantin did not prevent development of focal spiking but markedly reduced discharge frequency. The remarkably regular 1/secdischarges characteristically recorded in focal lesions of control animals were not observed in dilantin-treated animals. Cyclic alterations in intr.;nsic excitability of lesion sites were minimal in the latter preparations. Secondary foci developed in both groups but the amplitude and spread ofparoxysmalactivity from these foci were less conspicuous in treated animals. Dilantin effects on primary foci were not reproduced by barbiturates. Pentobarbital sodium even in relatively high concentrations failed to alter frequency and regularity of paroxysmal discharges at the lesion site. These and other data on the factors involved in development of focal discharges in cold lesions of neuronally isolated cortex indicate that dilantin reduced the "pacemaker potentiality" of cold-i~ured neurons. The consequences of this are reflected in rapid repolarization of elements involved in the initial trauma and suppression ofsubsequent rhythmically recurring non.synaptically induced fluctuations in neuronal excitability. I I. Aeti~,lty and excitability of pyramidal nmrones during seizures. - - L. Berlin (Bronx, N.Y.). Corticofugal discharges induced in the medullary pyramid by a single shock to the cerebral cortex can serve as indicators of the excitability of a known group of cortical cells. In the "resting" state a single shock to the unanesthetized cortex evoked a direct (D) wave followed for the next 4-5 msec by I or 2 indirect (I) waves, all of constant configuration. During seizures, there were marked fluctuations of these responses. The most common change consisted of a decrease of the D wave and the development of a large late I wave. Some responses demonstrated an enlarged D wave and depression of all I activity. The same problem was studied by recording spontaneous and evoked activity of single pyramidal neurones during the resting state and during seizures. Predictably a 0.01~ 0.03 msec cortical shock was followed within I.S msec by I-3 evoked action potentials. Metrazol induced seizureq yielded bursts of high frequency discharges for 0.2-0.5 sec followed by quiescent periods. Periods ofcontinuous firing for several so: were also noted. When the frequency of firing was maximal, the action potential amplitude was decreased. The response to corticalshockduring seizures varied widely. Usually the stimulus indaced a prolonged high frequency discharge for 40-80 msec; at other times there followed only a single spike or a delayed series of spikes. The variablility of cortical excitability during seizures suggests that seizure activity not only alters the pattern of discharge but sets up an intrinsic activity that dominates cortical activity so that it is no longer predictably responsive to external stimuli.
12. Phefle ~flmulation and matamflon in the Idttm. - - A. 1'. Dunn ~
I. J. Biumenthal (Northport, N.Y.).
The effc~'t of photi¢ stimulation upon evolution of cerebral
E/ectrocnceph, ¢//n. Neurophysiol., 1963, 15:921-925
924
SOCIETY PROCEEDINGS
activity (Grossman 1955; Kellaway 19~7)was inv,.stigated on the basis of 94 EEGs from 4"/unanesthetized kittens. The latter were divided into five groups, ranging in age from 1 day to 1 year, viz. : Group I: 1-30 days, N -- 32 kittens (68*/.), fifteen retested, total of 55 EEGs (59%); Groups I1 to V: 2-12 months, N -- 15 (32~), fourteen gepcated, 39 EEGs (41%). With the kitten at rest, the EEG patterns a few hours after birth present a mere baseline sway, with no response to physiological stimuli, such as sound and light. At five days the background rhythm reveals poorly organized traim of 6--T/see mcillatiom. Between 22 to 30 days of age two kittens showed multiple spiking. After 6 weeks high voltagepatternswith fast activity are seen. MaAed changes are noted after the 2nd month, with better organization and some increase in the basic frequency. One kitten in the 7-9 month Stoup revealed spike and wave formation. This ~roup and the 10-12 month group show basic 8-12/ sac activity in six kittem, whereas slower frequencies are seen in two other kittens. The initial response to photic stimulation is a negative spike discharge seen on the 10th day. Photic "driving" is first evoked at 22 days. By the 45th day photic "driving" is seen to some extent in all kittens. A positive correlation cougd be determined between increase of basic cerebral frequency and response to photic stimulation during the process of maturation. I$. Oscillatory, diytlmd~l atctlelty In qsually evoked reepomw from tim mmnesflmlsed monkey. - - J. R. HuGhes aM J, A, Mssuroweki (Buf~lo, N.Y.). Various types of rhythmical oscillatory activity have been pt~iously de~'ribed in visual cortical responses, evoked by a light flash under a variety of conditions in different animals, The present study deals with fast oscillatory rhythms, up to 200/see with subharmonics thereof, evoked by single flashes and noted mainly in the unanesthetized alert monkey. Under a variety of conditions, the latency to the onset or the response and to the first neptive peak varies attd may show a step.like change to the succeeding ne~tive wave. However, the latency to later wavelets tends to be constant with changes in the electrode position, intensity of stimulus and depth of anesthesia. Variations in these latter different conditions are associated with change in the number of wavelets, The largest number of wavelets appears (1) from electrode positions recording the higl~t amplitude evoked response (2) with the most intense stimuli and (3) in the most alert stage of awareness, Flora preliminary depth recording rhythmical activity can be seen from subcortical regions, but not so prominently as from the cortex. It seems possible that this rhythmical activity may be a ~ e r e l property of the entire visual system and p e r ~ of all sensory systems. The retina probably plays an important role here and may even drive this activity which is, ~wever, likely modified according to the ~ t a b i l i t y changes in the visual cortex.Thesignif. icance ofthese wavelets is questionable; they may be only an epipbenomenon without functional significance, and with only neurophysiolosical i n s t . However, it seems, at least, possible that these wavelets carrycoded neurophys.
iological information which may be of value to the re. sponding organism.
14. Blood p r e m n changes and after-discharges foliowb~ stimulation of the septum in the cat. - - J. Mulmwa and 0 . J. And)' (Olmyanm City, Japan and Jackson, Miss.). Introduction: Hippocampal after-discharges have been shown to produce a depression, elevation or no change in the blood pressure levels, dependent upon sites of stimulation. Since the septum occupies a significant anatomico. physiologic position in the hippocampal circuitry of the limbic system, it was postulated that also the septum possessed nuclei contributing to specifically directed blood pressure changes. The postulate was tested by eliciting after.discharges from the septum and correlating the sites of stimulation with response. The septal nuclei were divided into four groups as previously suggested by Andy and Stephan (1959 and 1962). Technique: Eighteen cats ,-'mmobilized with Anectine were utilized. Sixty-seven different points in the septum were stimulated with a Grass stimulator. Threshold induced after-discharges and blood pressure changes were recorded on a Grass electroencephalo~raph and Sanborn Twin-Viso respectively. EEG recordings were also taken from various parts of the hippocampus, the amygdala and brain-stem. Blood pressure changes of 10 mm Hg or greater were considered significant, Brains were serially sec. tioned and points of stimulation and recording were histologically verified. Results: The septal nucleus of the diapnal band of Broca had a very strong tendency to induce significant ele. rations of the blood pressure, Elevations were also in. duced by after.dischar~ elicited following stimulation of the anterior hippocampal continuation. Stimulation of the caudal group tended to depress the blood pressure, No significant c h a n ~ were induced by stimulation of the dorsal lroup of septal nuclei. It is of further interest to note that the nucleus acgumbans had a tendency to induee blood pressure depression. These results will be discussed in relation to septal afferent and efferent systems and propaption of the afterdischarges to various other iimbic structures includinlg the amygdala, (Aided in part by a grant (B.815) NIH). t& Effects of Inkc4toas of a c e t y ~ end edmedine in the breln4tem of cats m tin amplitude of semov7 evoked poteuthl~ . - J. P. Cordam, J ~ md J. Wabh (M~tnal, Qm., Cuaab). The p ~ n t series of experiments was designed to study the effects of topical ehe~nica| stimulation of the brainstem reticular formation on a specific sensory input. As a test object, the cortical evoked potential, produced by single shock stimulation of the optic pathways was used, and adrenaline and acetylcholine were injected directly into the pontiac and bulbar reticular formation of curarized or enc'd,~m/e isoH cats. Effe~ve adrenaline injections were followed by a transieat but significant lacrosse of this evoked potential occurring with;n 1 rain after the end of the injection. Acetyk:holin¢ injections on the other E/eclroencepk, din, NeurophysioL, 1963~ 13:921-925
EASTERN ASSOCIATIONOF ELECYrROENCEPHALOGRAPHERS hand produced two types of r~sponse. The first and more characteristic response -was a significant decrease of the evoked potential occurring along a time course similar to the adrenergic effect. The second type of response was biphasic and consisted of an early and short-lasting increase followed by the usual decrease below base line levels. For various reasons which will be discussed, we believe that the transient and inconstant increase of the evoked potential following acetyk:holine injections may be spurious experimental artefact such as a change secondary to the emetic effects of acetykholine which can be observed following similar injections in the chronic, freely moving animal. These results are interpreted in terms of the selective activation of two ascending reticular systems capable of modulating sensory input at thalamic and cortical levels. l& A ~ b u l l m r arm commlllnermpomm of the retieulmr activating system. - - M. B. Allen, Jr. and M, Bolm]t¢ (JLisoII, ~ l i d h r ~ FIlliP). This report describes alterations of el~trical activity of the cortex, sympathetics, parasympathetics, and muscles following the production of lesions in the medulla oblongata. Methods: Fifty.five unanesthetized adult cats were sub. jetted to recordings of the electrocortico~praphic and short ciliary nerve (SCN) responses to short reticular stimulations before end after acute lesions of the bulb. Recordings were obtained from the cervical sympathetic trunk and extensor muscles of the neck in selected experiments. Three other animals were monitored, 2, 13, and 38 days alter the stereotaxic placement of lesions utilizing electric coagulation. Lesions were histologically confirmed. Results: (I) Transactions of the bulb at the level of the rostml third of the hypoglossal nucleus and the middle of the inferior olive were followed by prolongation of the cortical and parasympathetic responses to mesencephalic reticular stimulations, (2) Similar alterations of cortical and SCN responses were obtained following discrete bilateral coagulations involving the nucleus of the tractus solitarius and that area between this nucleus and the floor of the 4th ventricle, Muscular responses were also prolonged. O) Following the production orthese lesions, animals frequently demonstrated spontaneous fluctuation~ of cortical and sympathetic activity, Simultaneous inverse reactions of SCN tone were noted. (4) These spontaneous fluctuations, as well as the alteration in the post.stimulation responses, indicate the
925
presence of a buffering mechanism which controls the reticular activating system and influences cortical tone, sympathetic and parasympathetic as well as motor discharges. 1% Eulogy to Charles Wattles Stephenson, 1897-1962. - H. Davis (St. Louis, Mo.). One of the founding members of the" Eastern Association of Electroencephalngraphers and also of the American EEG Society, Charles Wattles Stephenson, of South Hero, Vermont, died suddenly last August of a heart attack. It is hard to believe that the sprightly, irrepressible "Chick" Stephenson, small of stature but quick of wit, is dead. In our EEG societies Chick was one who worked hard behind the scenes to create both the form and the spirit of those organizations, although he characteristically avoided the center of the stage himself. He was at his best and made probably his greatest contributions as a member of the committees that drafted the original constitutions and later ir.~erpreted and revised them. He was for many years chairman of the Rules Committee of the American EEG Society, after serving only a single year as a member of the original Council. He had insisted on stepping aside first from the Council to initiate the rotation of members by annual election. During the war he volunteered his services and spent nearly 2 years at the Army Hospital in Memphis as head of the EEG service. Army and Navy units, such as his, improved FEG techniques and developed a large back-log of experience in viewing, studying, classifying and interpreting thousands upon thousands of EEGs. This mass of experience was one of the foundation stones of electroencephalography, and Stephenson, although he published little, was one of the most careful and critical of analysts. With his characteristic ingenuity and a flair for tools and their uses, he also made several technical contributions to the fabrication of electrodes, to the routtne of EEG measurement and to the systematic description and classification of normal, borderline and abnormal EEG patterns. We miss Chick as an able EEGer, We miss Chick as a keen formulator and interpretor of rules and as a wise, practical counselor. We also miss his cheery smile and his inimitable and continuous flow of anecdotes, rMdles and stories. At Mesnaqua Farm the friendly hospitality of Chick and his delightful wife, "Yardy", was boundless. Their spirit has been one of the priceless ingredients of the Eastern and of the American EEG societies. May others carry on the tradition.
El¢ctroencepb. din. Neuropb ysloL , 1963, 15" 921-925
~21
of sleep, since the simultaneous GSR variations reveal a heightening of the activation level, that is, it shows that the subject is more amused, Finally the authors agree that hypnosis is not a special state which a subject "goes into", "comes out of" (T.X. Batt)er), but a behaviour in wh/ch an active attitude of the subject, and the transactional process between the subject and the hypnotist, play an important role.
Electroenceph. clin. Neurophy$iol., 1963, 15:916-921
EASTERN ASSOCIATION OF ELECTROENCEPHALOGRAPHERS New York, N.Y., December 5, 1962
Secretary: DR. J. R. HUGHES 462 Grlder St,, BuB'alo, N.Y. (U.S.A.)
I. Paroxysmal bllndneu.--H, Strauss (New York, N.Y.). This boy, 11 years old, has suffered from attacks of complete blindness with preservation of consciousness, lasting between 2 and 10 rain. The EEG shows almost continuous spike and wave patterns with frequencies from 1.5 to 3 per ~ , sometimes with double spikes, at the occipital electrodes, often simultaneously at the posterior temporal and, more rarely, the parietal electrodes, with a voltabe up to 200 pV. The number of these bursts decream with opening of the eyes, flicker with frequencies of 4 or more per sec and hyperventiiation, Mental activity has no in. fluenos, Neurological examination, including visual fields, optokinetic nystqmus was entlre!y neptive. Contrary to those cases with ictal blindness, in which the d i g h a r p started from one occipital region, one is dealing here with a osntrenosphalic disturbance, affecting maximally the o~ipital region. No similar case seems to have been pub. lished. The abnormal EEG and all clinical phenomena were promptly controlled by a combination of Tridione and Dilantin. 2 . - c . m t m e e p m u e ' eh~~emk~rsphk m u m . in ~ idmr~y, - - R, G. ~ md K. Abm-
hm (Bema~ Md.), Four cases of true precocious puberty associated with an EEG patten, sugBestive of "osntrenosphalic" origin (23.5/see bilateral and relatively synchronous and symmetrical spike and wave complexes) are presented, and three similar casesare r e p o ~ from the literature. Three of the present four cases exhibited clinical-radiological ~..idence indicative of precocious puberty of the "cerebral" type with probable lesions in the area of the hypothalamus and 3rd ventricle. An analysis of these cases suggests flint bilateral spike and wave discharges, often associated with seizures, may be a not uncommon finding in precocious
puberty of the cerebral type, and that these EEG patterns may occur with structural lesions in these areas even in the absence of other neurologic manifestations. The clinical-pathological and experimental evidence in support of the hypothetical "centrencephalon" of Penfield and Jasper as the site of origin of the 3/see spike and wave complex still remains rather controversial. However, the occurrence of this EEG pattern in association with a syndrome accompanied by organic lesions in those subcortical regions likely included in the ill.defined and hylmthetical "osntrencephalic" center, lends clinical support to the role of these regions in the patho.physiologlcal mechanisms of these EEG patterns. (Full paper in press in Elect~e,¢eph. olin. Neurophyslol., 1953). 3. Sleep BEGs in a IMe-tm-Me, ~ type of ~,oner pelmlm/on. - - W. J. (Allmm.. N.Y.). The recent EEG literature contains numerous references to the association between 14 and 7 per sec Ix~iiti~ spikes and behavior disorders with only an occasional report of negative findings. In the last year, sleep EEGs were ob. rained on 20 inmates of the New York State Vocational Institute who ranged in age from 16 to 20 years; they were all assigned to a special project to evaluate the care of younf epileptics in a penal institution. In most cases, their seizures were atypical and, indeed, in several it was felt that they did not suffer from epilepsy at 411.All were serving sentences for crimes that could not~reasonablyroe directly due to their epilepsy; none of them were institutionalized for a single crime and none had an I.Q. below borderline normal. Based on the literature, it was expected that there would be a relatively high incidence of"14 and 7" but in no case was such an electrographic configuration seen. The sleep EEGs of 27 other patients in the same abe group done over the same period of time were reviewed; in most of these casessleep EEGs were indicated because
Electrofnceph.din. Neurophysiol.,1963, 13:921-925
922
S4X'IETY PROCEEDINGS
of a possible diagnosis of epilepsy; five of this "control" group had "14 and 7". The possible reasons for these findings in the prisoners will be discussed. 4t. EEG in myotoain dystrophlea. - - J. Biltenbender and W. F ~ ( ~ Pa. and Albany, N.Y.). Myotonia dystrophica is a disease which involves a number of different bodily systems. However, in spite of repeated references to behavioral and intellectual abnormalities and pneumoencephalographic evidence of brain atrophy, there has been no evaluation of cerebral function as measured by EEG except in a few isolated case reports. The EEGs of 23 adult patients suffering from myotonia dystrophica were obtained. All had EEGs which were within the range of normal except for four who varied from the usual criteria of normal by having an "alpha" rate of less than 8/see. Even independent of these four patients, the myotonic patients as a group had a slower average alpha rate than an aged.matched control group. The basis for this EEG finding in myotonic patients cannot be definitely ascertained from our series but the suggestion can bc offered that this is at least in part a reflection of their not infrequent mild hypothyroidism.
5. Eleetro~eeplmle~zphic, eeflleogmphle and intraeerebral potentbds in two anatomically verified cases of Creutdeldt-.]laeob Disease. - - M. Raype.t (NewYork, N.Y,).
Electrophysiological observations have been made on two cases of Creutzfeldt.Jacob (CJ) disea,se under a combined program of neurochemical, ultrastructural and electro. graphic investigations of degenerative disease,s of the brain (Korey et oL, American Academy t~f Neurology,
196~), The histological diagnosis in these two cases is based on brain biopsy specimens and autopsy material, At the cortical recording site, as well as elsewhere in the cortex, there was mild to marked loss of cortical neurones and alteration of the staining characteristics of many of the remaining ganglion cells, Sharply demarcated"microcysts" and swollen Mtrocytes were present in the neuropil, Neuro6brillary tangles and senile plaques were absent. The histologtc picture was considered to be consistent with CJ disease (R. D. Terry). Scalp ele~roencephalolFams were characterized by periodic bursts of high voltage positive-negative spikes and triophasic potentials recurring continuously at inter. pals ranging from 0.5 to 2 sac (Heeler, Lesse and Austin 1958; Alem~, Vizioli and Reda 1959), In the electrocorti. cobras taken during craniotomy similar complexes were recorded from the plal surface of the second right frontal convolution. Complete neuronal isolation of a portion (2.5 × 2 cm) of this ~ r u s resulted in very marked amplitude attenuation of these discharges, Amplitude attenuation of minor extent was observed when one of the pial recording ~ele~rodes was moved from cortex to white matter exposed by cortical biopsy. Intracerebral record. in8 with depth electrodes revealed the periodic complexes to be siwpler and of low amplitude in the white matter.
However, high voltage tri-phasic complexes resembling those recorded from the scalp znd the pial surface were again encountered in the subcortical grey matter (globus pallidus). These findings indicate two separate loci for the generation of the periodic bursts. The relationship of the subcortical and cortical activity to each other and to the scalp electroencephalogram will be discussed. 6. Evoked visual cortical responses in homonymous hemianopic defects in man. --- R. Cohn ~ M&). By the use of linear summating techniques (Mnemotron CAT) it is observed that 50 to 230 trains of photic stimulation, of variable frequency, generate essentially equal amplitude potentials from the occipital regions in nearly all normal individuals. Using similar derivatioqs (electrode arrays) it has been observed that with approxtmately 3 to 10 per sec stimulation there is a prominent amplitude asymmetry in the occipital outputs in all patients studied who clinically demonstrated lateral homonymous hemianopic defects. in some patients the lower amplitude potentials evoked from the involved side showed only a second harmonic output. These findings appear more reproducible than the changes observed, under similar conditions, using a stimulus pulse cycle of around I per sac. 7. A ,ew audio mote' system In man. - - R. G. Bitkfe.d, J, L. Jaeeblen and R.F. Galbralth 0tedmter, Minn.).
(n the course of observations using a CAT average response computer, an audio motor response system has been discovered, When click stimuli having intensities of I00~135 Db. (750 cycles basic frequency damped o~illa. lion) are applied to the ear in normal human subjects, a widespread response can be detected in facial, cranial and limb musculature. This can be clearly seen in averages of 100~150 responses when its amplitude may range from 10ol00 I,V. The latency is remarkably short in the cervical muscles (8-10 reset) indicating a simple two or three neurone-are pathway through the brainatem. The ampli. tude of the response is related to tension in the muscles and it disappears on complete relaxation. It is buried in voluntary EMG activity and usually cannot be seen in the un. processed raw data. Experiments, including curarization and manipulation of mu~le tension, indicate that while the response is myogenic in origin, it is capable of subtle imitation of genuine cortical evoked potentials, This fast audio motor response can be separated by latency from other known motor systems, For instance, the latency in the cervical muscles recorded inthe neck, is 8-10 msec for the fast response, 25 re.see for I "startle" response to a pistol shot and 100 msec for a voluntary movement response to an auditory stimulus. The function of this fast system is presently unknown, but its peg. sible implication in the pmma efferent system is being explored, It appears that "downstream" or centrifugal averaging in which probabilistic events in the contracted muscle mirror central processes may have wide application in neurologic research. ($upporledbyUSPHS(Tront B2056).
Electroencepb.din Neuropkysio/.,1963, I$: 921-925
EASTERN ASSOCIATIONOF ELECTROENCEPHALOGRAPHERS g. A factor ~amlyticshMy of ciinieal and electroeacephaiographic variables in epileptic patients. - - E, A. Rodin sad Y. L~ (Detroit, Mich.). Fifty-seven epileptic patients were investigated in detail from the clinical, neurological, psychiatric, psychologic, and electroencephalographic point of view. A seizure was induced by Mcgimide administration in all patients and the attack was pho~-~,~hed. The results of the investigations were coded in detail to allow automatic data processing. 155 variables were then selected for inter-correlations and 1,089 statistically significant correlations were obtained. Eighty variables which had shown the highest correlation coefficients were subsequently chosen for factor analysis. By means of the principal axes method and varimax rotation, eleven factors were extracted and identified. In view of time considerations the discussion will be limited to the presentation of three factors. The first factor deals with severity of seizure disorders, diffuse brain damage, and slowing of the background rhythms in the electroencephalogram. It contrasts differentiating features between the "deteriorated" epileptic and the patient with a seizure disorder but a normal mentality. The second factor shows differences between centrencephalic and focal cortical seizure disorders. Sociopathic behavior, behavioral difficulties in school, and difficulty concentrating were found to be related to the centrencephalic group which was abe younger in age. The third factor to be discussed deals with aspects of those patients whose induced Grand Mal seizure started with a gradual build-up of discharges in the left temporal area and pointed out, in addition to certain clinical features of the attack pattern, the importance of the post-ictal clinical phenomena in assessing the locus of origin of the epileptic discharge. In view of the fact that the number of patients investi. gated was still relatively small the study will be repeated on another sample.
9. Cliniadepllepflformselzuresorlainaflnslnchronle partially imlated e e r d n l cortex. - - F. A, Fa~tlln and k. Batters (New York, N.Y.). Further evidence is presented that rhythmic stimulation of a peripheral nerve will precipitate epik~tiform electrical activity selectively from an area of co:~nic, partially neuronally isolated, frontal cerebral cortex. In some animals this local epileptiform discharge spread ~md caused a generalized clinical seizure. tO. Effects of dilantin on focal eplleptoganle activity of cat neocortex. - - F. S. MusErsve u d D. P. Parpam (New York, N.Y.). The magnitude and duration of injury pot~tials, discharge frequency and characteristics of secondary homolateral and contralaterai projection activity have been studied in control and dilantin-treated cats following production of standard 4 mm-diameter cold lesions of suprasylvian cyrus. Treated animals received approximately 10 mg/kg/ day i.m. dilantin for 2 weeks or more prior to production
923
of freezing lesions. Negative injury potentials generated at the lesion site were significantly smaller in amplitude and shorter in duration in dilantin-treated animals than in controls. Dilantin did not prevent development of focal spiking but markedly reduced discharge frequency. The remarkably regular 1/secdischarges characteristically recorded in focal lesions of control animals were not observed in dilantin-treated animals. Cyclic alterations in intr.;nsic excitability of lesion sites were minimal in the latter preparations. Secondary foci developed in both groups but the amplitude and spread ofparoxysmalactivity from these foci were less conspicuous in treated animals. Dilantin effects on primary foci were not reproduced by barbiturates. Pentobarbital sodium even in relatively high concentrations failed to alter frequency and regularity of paroxysmal discharges at the lesion site. These and other data on the factors involved in development of focal discharges in cold lesions of neuronally isolated cortex indicate that dilantin reduced the "pacemaker potentiality" of cold-i~ured neurons. The consequences of this are reflected in rapid repolarization of elements involved in the initial trauma and suppression ofsubsequent rhythmically recurring non.synaptically induced fluctuations in neuronal excitability. I I. Aeti~,lty and excitability of pyramidal nmrones during seizures. - - L. Berlin (Bronx, N.Y.). Corticofugal discharges induced in the medullary pyramid by a single shock to the cerebral cortex can serve as indicators of the excitability of a known group of cortical cells. In the "resting" state a single shock to the unanesthetized cortex evoked a direct (D) wave followed for the next 4-5 msec by I or 2 indirect (I) waves, all of constant configuration. During seizures, there were marked fluctuations of these responses. The most common change consisted of a decrease of the D wave and the development of a large late I wave. Some responses demonstrated an enlarged D wave and depression of all I activity. The same problem was studied by recording spontaneous and evoked activity of single pyramidal neurones during the resting state and during seizures. Predictably a 0.01~ 0.03 msec cortical shock was followed within I.S msec by I-3 evoked action potentials. Metrazol induced seizureq yielded bursts of high frequency discharges for 0.2-0.5 sec followed by quiescent periods. Periods ofcontinuous firing for several so: were also noted. When the frequency of firing was maximal, the action potential amplitude was decreased. The response to corticalshockduring seizures varied widely. Usually the stimulus indaced a prolonged high frequency discharge for 40-80 msec; at other times there followed only a single spike or a delayed series of spikes. The variablility of cortical excitability during seizures suggests that seizure activity not only alters the pattern of discharge but sets up an intrinsic activity that dominates cortical activity so that it is no longer predictably responsive to external stimuli.
12. Phefle ~flmulation and matamflon in the Idttm. - - A. 1'. Dunn ~
I. J. Biumenthal (Northport, N.Y.).
The effc~'t of photi¢ stimulation upon evolution of cerebral
E/ectrocnceph, ¢//n. Neurophysiol., 1963, 15:921-925
924
SOCIETY PROCEEDINGS
activity (Grossman 1955; Kellaway 19~7)was inv,.stigated on the basis of 94 EEGs from 4"/unanesthetized kittens. The latter were divided into five groups, ranging in age from 1 day to 1 year, viz. : Group I: 1-30 days, N -- 32 kittens (68*/.), fifteen retested, total of 55 EEGs (59%); Groups I1 to V: 2-12 months, N -- 15 (32~), fourteen gepcated, 39 EEGs (41%). With the kitten at rest, the EEG patterns a few hours after birth present a mere baseline sway, with no response to physiological stimuli, such as sound and light. At five days the background rhythm reveals poorly organized traim of 6--T/see mcillatiom. Between 22 to 30 days of age two kittens showed multiple spiking. After 6 weeks high voltagepatternswith fast activity are seen. MaAed changes are noted after the 2nd month, with better organization and some increase in the basic frequency. One kitten in the 7-9 month Stoup revealed spike and wave formation. This ~roup and the 10-12 month group show basic 8-12/ sac activity in six kittem, whereas slower frequencies are seen in two other kittens. The initial response to photic stimulation is a negative spike discharge seen on the 10th day. Photic "driving" is first evoked at 22 days. By the 45th day photic "driving" is seen to some extent in all kittens. A positive correlation cougd be determined between increase of basic cerebral frequency and response to photic stimulation during the process of maturation. I$. Oscillatory, diytlmd~l atctlelty In qsually evoked reepomw from tim mmnesflmlsed monkey. - - J. R. HuGhes aM J, A, Mssuroweki (Buf~lo, N.Y.). Various types of rhythmical oscillatory activity have been pt~iously de~'ribed in visual cortical responses, evoked by a light flash under a variety of conditions in different animals, The present study deals with fast oscillatory rhythms, up to 200/see with subharmonics thereof, evoked by single flashes and noted mainly in the unanesthetized alert monkey. Under a variety of conditions, the latency to the onset or the response and to the first neptive peak varies attd may show a step.like change to the succeeding ne~tive wave. However, the latency to later wavelets tends to be constant with changes in the electrode position, intensity of stimulus and depth of anesthesia. Variations in these latter different conditions are associated with change in the number of wavelets, The largest number of wavelets appears (1) from electrode positions recording the higl~t amplitude evoked response (2) with the most intense stimuli and (3) in the most alert stage of awareness, Flora preliminary depth recording rhythmical activity can be seen from subcortical regions, but not so prominently as from the cortex. It seems possible that this rhythmical activity may be a ~ e r e l property of the entire visual system and p e r ~ of all sensory systems. The retina probably plays an important role here and may even drive this activity which is, ~wever, likely modified according to the ~ t a b i l i t y changes in the visual cortex.Thesignif. icance ofthese wavelets is questionable; they may be only an epipbenomenon without functional significance, and with only neurophysiolosical i n s t . However, it seems, at least, possible that these wavelets carrycoded neurophys.
iological information which may be of value to the re. sponding organism.
14. Blood p r e m n changes and after-discharges foliowb~ stimulation of the septum in the cat. - - J. Mulmwa and 0 . J. And)' (Olmyanm City, Japan and Jackson, Miss.). Introduction: Hippocampal after-discharges have been shown to produce a depression, elevation or no change in the blood pressure levels, dependent upon sites of stimulation. Since the septum occupies a significant anatomico. physiologic position in the hippocampal circuitry of the limbic system, it was postulated that also the septum possessed nuclei contributing to specifically directed blood pressure changes. The postulate was tested by eliciting after.discharges from the septum and correlating the sites of stimulation with response. The septal nuclei were divided into four groups as previously suggested by Andy and Stephan (1959 and 1962). Technique: Eighteen cats ,-'mmobilized with Anectine were utilized. Sixty-seven different points in the septum were stimulated with a Grass stimulator. Threshold induced after-discharges and blood pressure changes were recorded on a Grass electroencephalo~raph and Sanborn Twin-Viso respectively. EEG recordings were also taken from various parts of the hippocampus, the amygdala and brain-stem. Blood pressure changes of 10 mm Hg or greater were considered significant, Brains were serially sec. tioned and points of stimulation and recording were histologically verified. Results: The septal nucleus of the diapnal band of Broca had a very strong tendency to induce significant ele. rations of the blood pressure, Elevations were also in. duced by after.dischar~ elicited following stimulation of the anterior hippocampal continuation. Stimulation of the caudal group tended to depress the blood pressure, No significant c h a n ~ were induced by stimulation of the dorsal lroup of septal nuclei. It is of further interest to note that the nucleus acgumbans had a tendency to induee blood pressure depression. These results will be discussed in relation to septal afferent and efferent systems and propaption of the afterdischarges to various other iimbic structures includinlg the amygdala, (Aided in part by a grant (B.815) NIH). t& Effects of Inkc4toas of a c e t y ~ end edmedine in the breln4tem of cats m tin amplitude of semov7 evoked poteuthl~ . - J. P. Cordam, J ~ md J. Wabh (M~tnal, Qm., Cuaab). The p ~ n t series of experiments was designed to study the effects of topical ehe~nica| stimulation of the brainstem reticular formation on a specific sensory input. As a test object, the cortical evoked potential, produced by single shock stimulation of the optic pathways was used, and adrenaline and acetylcholine were injected directly into the pontiac and bulbar reticular formation of curarized or enc'd,~m/e isoH cats. Effe~ve adrenaline injections were followed by a transieat but significant lacrosse of this evoked potential occurring with;n 1 rain after the end of the injection. Acetyk:holin¢ injections on the other E/eclroencepk, din, NeurophysioL, 1963~ 13:921-925
EASTERN ASSOCIATIONOF ELECYrROENCEPHALOGRAPHERS hand produced two types of r~sponse. The first and more characteristic response -was a significant decrease of the evoked potential occurring along a time course similar to the adrenergic effect. The second type of response was biphasic and consisted of an early and short-lasting increase followed by the usual decrease below base line levels. For various reasons which will be discussed, we believe that the transient and inconstant increase of the evoked potential following acetyk:holine injections may be spurious experimental artefact such as a change secondary to the emetic effects of acetykholine which can be observed following similar injections in the chronic, freely moving animal. These results are interpreted in terms of the selective activation of two ascending reticular systems capable of modulating sensory input at thalamic and cortical levels. l& A ~ b u l l m r arm commlllnermpomm of the retieulmr activating system. - - M. B. Allen, Jr. and M, Bolm]t¢ (JLisoII, ~ l i d h r ~ FIlliP). This report describes alterations of el~trical activity of the cortex, sympathetics, parasympathetics, and muscles following the production of lesions in the medulla oblongata. Methods: Fifty.five unanesthetized adult cats were sub. jetted to recordings of the electrocortico~praphic and short ciliary nerve (SCN) responses to short reticular stimulations before end after acute lesions of the bulb. Recordings were obtained from the cervical sympathetic trunk and extensor muscles of the neck in selected experiments. Three other animals were monitored, 2, 13, and 38 days alter the stereotaxic placement of lesions utilizing electric coagulation. Lesions were histologically confirmed. Results: (I) Transactions of the bulb at the level of the rostml third of the hypoglossal nucleus and the middle of the inferior olive were followed by prolongation of the cortical and parasympathetic responses to mesencephalic reticular stimulations, (2) Similar alterations of cortical and SCN responses were obtained following discrete bilateral coagulations involving the nucleus of the tractus solitarius and that area between this nucleus and the floor of the 4th ventricle, Muscular responses were also prolonged. O) Following the production orthese lesions, animals frequently demonstrated spontaneous fluctuation~ of cortical and sympathetic activity, Simultaneous inverse reactions of SCN tone were noted. (4) These spontaneous fluctuations, as well as the alteration in the post.stimulation responses, indicate the
925
presence of a buffering mechanism which controls the reticular activating system and influences cortical tone, sympathetic and parasympathetic as well as motor discharges. 1% Eulogy to Charles Wattles Stephenson, 1897-1962. - H. Davis (St. Louis, Mo.). One of the founding members of the" Eastern Association of Electroencephalngraphers and also of the American EEG Society, Charles Wattles Stephenson, of South Hero, Vermont, died suddenly last August of a heart attack. It is hard to believe that the sprightly, irrepressible "Chick" Stephenson, small of stature but quick of wit, is dead. In our EEG societies Chick was one who worked hard behind the scenes to create both the form and the spirit of those organizations, although he characteristically avoided the center of the stage himself. He was at his best and made probably his greatest contributions as a member of the committees that drafted the original constitutions and later ir.~erpreted and revised them. He was for many years chairman of the Rules Committee of the American EEG Society, after serving only a single year as a member of the original Council. He had insisted on stepping aside first from the Council to initiate the rotation of members by annual election. During the war he volunteered his services and spent nearly 2 years at the Army Hospital in Memphis as head of the EEG service. Army and Navy units, such as his, improved FEG techniques and developed a large back-log of experience in viewing, studying, classifying and interpreting thousands upon thousands of EEGs. This mass of experience was one of the foundation stones of electroencephalography, and Stephenson, although he published little, was one of the most careful and critical of analysts. With his characteristic ingenuity and a flair for tools and their uses, he also made several technical contributions to the fabrication of electrodes, to the routtne of EEG measurement and to the systematic description and classification of normal, borderline and abnormal EEG patterns. We miss Chick as an able EEGer, We miss Chick as a keen formulator and interpretor of rules and as a wise, practical counselor. We also miss his cheery smile and his inimitable and continuous flow of anecdotes, rMdles and stories. At Mesnaqua Farm the friendly hospitality of Chick and his delightful wife, "Yardy", was boundless. Their spirit has been one of the priceless ingredients of the Eastern and of the American EEG societies. May others carry on the tradition.
El¢ctroencepb. din. Neuropb ysloL , 1963, 15" 921-925