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Southern electroencephalographic society
FRENCH SOCIETY 31. The EEG and the impairment of sleep by traffic noise during the night: a problem of preventive medicine. - H. R. Richter (Basle, Switzerland).
Continuous E E G monitoring of sleep reveals easily variations in depth following sensory stimuli. Together with the appearance of K complexes this objectively demonstrates a more or less frequent impairment of sleep, of which the individual concerned is usually un-
291
aware. Noise associated with modern civilization (automobiles, trucks, elevated and underground railways, jets) and even natural sounds (birds, etc.) frequently disturb the rest of sleepers - - the trophotropic phase of restitution - - and in this way help facilitate neurovegetative imbalance and lability. City builders and traffic engineers should take into consideration the need and right of every h u m a n to rest, a factor indispensable for health.
Electroenceph. clin. Neurophysiol., 1967, 23:283-291
SOUTHERN ELECTROENCEPHALOGRAPHIC SOCIETY Tulsa, Okla., November 4-6, 1966
Secretary: ROBERT L. GREEN JR., M . D . Psychiatry Service, Veterans Administration
1. The six per second spike and wave complex (the wave and spike phantom). - - B. R. Tharp (Durham, N.C.).
The "6/see spike and wave complex" has been correlated clinically with such phenomena as seizures, headaches, syncope, abdominal pain, personality disorders and psychoses. It is reported to occur in 0.4--1 ~ of patients undergoing EEG and is more commonly seen in females, usually in the third and fourth decades. The incidence of 6/sec spike and wave discharge was determined to be 1 . 5 ~ in a group of 195 healthy adult males during routine EEG recording in which the comparison montage (which compares symmetrical scalp areas in the same channel) was used for at least 5 min of each recording. The i.v. injection of diphenhydramine (50 mg) activated the spike and wave phenomena in 10 out of 34 subjects with normal control recordings. This study suggests that the 6/sec spike and wave discharge is a normal physiologic cerebral discharge which can be provoked by the i.v. administration or a centrallyacting antihistamine. 2. Significance of obtaining four phases of sleep in children. - - H. E. Goldman (Tulsa, Okla.).
It has been well documented that in EEG work with children sleep tracings are extremely valuable. There is great difficulty in obtaining sleep tracings in the group of patients who are hyperactive whether by virtue of emotional upset or mental retardation. Various techniques have been applied to induce the 4 stages of sleep. A review of the literature would suggest that the use ofchlorpromazine for the induction of sleep rarely has been attempted. This is a study of 25 patients with tracings done under the influence of this drug during sleep and waking in order to illustrate the following points: (1) Whether or not sleep tracings are readily obtained in children with the use of
Hospital,
Durham, N.C. (U.S.A.)
chlorpromazine, the length of time of induction of sleep and the presence of undesirable side effects. (2) The production of actual natural sleep in patients with chlorpromazine, with the corresponding EEG changes thereof. (3) The fact that chlorpromazine during the tracing has had no undesirable effects on the EEG, with subsequent ease of interpretation. The findings in 25 cases, before and after chlorpromazine administration, will be presented with a discussion of abnormalities produced. 3. Some observations on the physiological mechanisms of "thalamic" pain. - - R. Musella, M. J. Short, W. P. Wilson and B. S. Nashold (Durham, N.C.).
The physiological mechanisms responsible for the diffuse burning quality of painful sensations following lesions of the thalamus are unknown. The recent observation that discharging lesions in the mesencephalon can give rise to painful sensations may account for the spontaneous paroxysms of pain suffered by these patients. However, it is possible that inhibitory feedback from the cortex and thalamus to the reticular system may be abolished, resulting in the byperesthesia occurring in these patients. In an effort to test this hypothesis we have studied twelve cats, six as acute and six as chronic preparations. In these animals radio-frequency lesions were made in the nucleus ventralis postero-lateralis (VPL) of the thalamus. Before and after the lesions evoked potentials were recorded from the reticular formation, VPL and sensory cortex after stimulation of the sciatic nerve. These evoked potentials were averaged and recorded, using a Nuclear Chicago 3100 Computer. It was observed that evoked potentials in the reticular system were abolished with acute lesions in the thalamus. If a period of 5 or more days were allowed to elapse, these potentials returned. Amplitude and wave form data, relative to the longitudinal changes occurring after lesions, are still incomplete. These
Electroenceph. clin. Neurophysiol., 1967, 23:291-293
292
SOCIETY PROCEEDINGS
will be presented in detail and their significance in regard to the phenomenon of thalamic pain discussed. 4. Electro-clinical correlations of polyphasic spike discharges. - - L. Musella, D. T. Gianturco and W. P. Wilson (Durham, N.C.). This study was carried out to investigate the findings of polyphasic discharges and spike and wave complexes appearing maximally, over the central region in children, first described by Y. Gastaut (1951) and more recently by Ricci and Scarinci (1962). In addition to the children, the study includes a number of adults with cerebral palsy, showing the typical polyphasic discharges. The clinical and electrographic records of more than 100 patients were examined. Often the electrical discharges spread from the central region to include the temporal regions. Occasionally the frontal or parieto-occipital regions were involved. They are markedly sleep- and drowsiness-sensitive. The background rhythms are usually normal. Hyperventilation and photic stimulation do not activate the records. A group of patients with high voltage polyphasic discharge limited to the occipital regions was also studied and these cases are being followed to determine whether they represent a different entity or whether they should be included in the so-called "rolandic epilepsy". Another group of patients with polyphasic discharges were seen in association with hypsarrhythmic discharges. This group is being followed also and raises interesting speculations about the prognosis. In conclusion, the polyphasic spike described by Ricci and Scarinci is not specific to rolandic epilepsy but may be seen in a variety of clinical conditions and in different age groups. 5. Further studies on reference electrodes. - - T. W. Robinson and E. O. Johnson (Birmingham, Ala.). Further studies have been made on EEG reference electrodes since our report of last year on the successful use of the various types of neck electrodes. With these "inactive" EEG reference electrodes, the E K G potential gradients were mapped around the neck and on the scalp. Since then, more simplified types of indifferent electrodes have been investigated. These are based on the principle of placing the potential from the reference electrode on both grids 1 and 2 of the amplifier. As a result of these studies, it was shown that the resistance between electrodes was independent of the inter-electrode distance and, although the resistance between the electrodes increases with time, it can change over a wide range without increasing the amount of interference. It was further indicated that if the indifferent reference electrodes are placed on the body and the exploring electrode on the scalp, both E K G and EEG changes will be displayed. However, if the reference and exploring electrodes are both placed on the scalp mainly the EEG changes will be shown. 6. The amygdala and hippocampus in olfactory aura. - O. J. Andy (Jackson, Miss.). In the present case report, the amygdaloid system is
differentiated from the hippocampal system in the elaboration of an olfactory aura. A 38-year-old white male received a blow on the right side of the skull with the butt of a rifle 6 years previous to admission. A right subdural hematoma was removed. He subsequently developed seizures characterized by an onset of "dizziness" and followed by an olfactory sensation of foul odor such as vomitus. A sense of lightheadedness and mingled thoughts developed. He occasionally heard voices which gave him commands to do things. He had periods of automatic behavior with lack of conscious awareness of his acts. EEG studies revealed a predominant right temporal focal involvement. Under local anesthesia, the right amygdala and hippocampus were exposed and bipolar electrodes placed in each structure. Bipolar electrical stimulation of the amygdala produced an after-discharge lasting 21 sec and spreading to the adjoining hippocampus. The patient became excited, restless and agitated. He complained of a foul odor and stated it was similar to his experiences during the seizures. Electrical stimulation of the hippocampus produced a discharge lasting 16 sec with minimal spread to the amygdala, and it was not accompanied by an olfactory aura. The amygdala was isolated from the hippocampus by a transverse section between the two structures and extending to the medial surface of the temporal lobe cortex. The contiguity from the amygdala to the basal forebrain structures, and that of the hippocampus to the entorhinal cortex remained intact. Following the surgical isolation of these structures, electrical stimulation of the amygdala produced a local after-discharge which lasted 20 sec and was accompanied by agitation, restlessness, and recurrence of the olfactory aura. There was no simultaneous spread of the after-discharge to the hippocampus during this episode. Stimulation of the hippocampus produced an after-discharge which did not spread to the amygdala and there was no accompanying olfactory hallucinations, restlessness or agitation. The amygdala and temporal cortical tip were excised, and the hippocampus was left intact. During a 6-month post-operative period, the patient has had no recurrent episodes of the psychomotor seizures. Conclusion: In this case, the olfactory component of the psychomotor seizure appeared to be dependent upon an after-discharge occurring in the amygdaloid system. Involvement of the hippocampal system with the after-discharge was not essential for the elaboration of the olfactory hallucination. 7. Centreneephalie seizure discharges in patients with focal hemispheral lesions. - - L. F. Stewart and F. E. Dreifnss (Charlottesville, Va.). The concept of primary and secondary bilateral synchrony is reviewed from the clinical and experimental standpoints. Five illustrative cases are presented. All of them show evidence of focal cerebral hemispheral disease and the EEG findings are those of bilaterally synchronous spike and wave discharges. It is concluded that these represent examples of secondary bilateral synchrony. Whereas the existence of primary bilateral synehrony is not denied, it
Electroenceph. clin. NeurophysioL, 1967, 23:291-293
SOUTHERN SOCIETY is emphasized that there is n o constant and reliable way to distinguish it from secondary bilateral synchrony electroencephalographically, and it seems likely that most cases of presumed primary brain-stem epilepsy are in fact examples of secoadary bilateral synchrony. From the early onset of epilepsy in these patients and others in the literature, it is concluded that the significance of the bilaterally synchronous spike and wave discharge is that it reflects a stage in the maturation of the nervous system. It is not synonymous with "centrencephalic" or with "idiopathic" epilepsy. 8.
Death?. - - H. M. Hauser and E. J. Brewer Texas).
(Houston,
A 6-week-old infant who appeared to be dead was revived with massive stimulation, but required continuous resuscitation in a Lindley Infant Respirator to prevent recurrence of cessation of all signs of life. Electroencephalographically, it was demonstrated that this was due to high brain-stem seizures with suppression of cortical activity, brief myoclonic twitchings of face and eyelids, followed immediately by isoelectricity, cardiac asystole and apnea. The brief myoclonic seizures continued while the child was well oxygenated in the respirator, but without the post-ictal isoelectricity or asystole. The seizures were controlled with Dilantin and Phenobarbital, and the child resumed spontaneous respiration on the third hospital day. At 8 months he was normal on examination and showed no signs of cerebral damage. He had remained seizure-free on Dilantin and his E E G was normal for his age. It is suggested that this may explain rare instances of misdiagnosed infant death. 9. Electroencephalograms in the 65 and over. - - H. M. Hanser (Houston, Texas).
During the first 4 months of Medicare, an increased number of private patients in the age group 65 and over
293
were studied electroencephalographically. A review of the experience in several hospital units in a large metropolitan area demonstrated most of the increase in recordings was in elderly people in old established neighborhoods. This included predominantly those aged 75 and above with obvious severe cerebral pathology and abnormal records. These people are now being hospitalized and studied more thoroughly. At this early stage in the Medicare program it was not apparent whether the EEG had proven itself beneficial in the diagnosis, management, or eventual disposition of this particular group of patients. The lack of any significant increase in normal records and only a small increase in abnormal records from the age group 65-74 indicated that the electrographic study of patients with cerebral symptoms of a minor nature has not been influenced by the new law. 10. Effect of triiodothyronine on human visual evokedpotentials. - - M. J. Short and W. P. Wilson (Durham,
N.C.). Triiodothyronine was administered to adult male volun teers for 3 days. Photically elicited occipital evoked potentials were recorded prior to and subsequent to the administration of the hormone. Consistent changes occurred in the evoked potential, characterized by increased duration and voltage of the secondary component, waves V, VI and VII, with facilitation of the rhythmic after-discharge. These findings corroborate previous work performed upon the CNS of the eat under the influence of elevated levels of thyroid hormone. In man, as in the cat, there is a relative diminution of reticular activating system influence upon the electrophysiological function of the CNS. Various signs and symptoms of hyperthyroidism are discussed as they may relate to such changes in reticular formation activity.
Flectroeneeph. clin. Neurophysiol., 1967, 23:291-293
Continuous E E G monitoring of sleep reveals easily variations in depth following sensory stimuli. Together with the appearance of K complexes this objectively demonstrates a more or less frequent impairment of sleep, of which the individual concerned is usually un-
291
aware. Noise associated with modern civilization (automobiles, trucks, elevated and underground railways, jets) and even natural sounds (birds, etc.) frequently disturb the rest of sleepers - - the trophotropic phase of restitution - - and in this way help facilitate neurovegetative imbalance and lability. City builders and traffic engineers should take into consideration the need and right of every h u m a n to rest, a factor indispensable for health.
Electroenceph. clin. Neurophysiol., 1967, 23:283-291
SOUTHERN ELECTROENCEPHALOGRAPHIC SOCIETY Tulsa, Okla., November 4-6, 1966
Secretary: ROBERT L. GREEN JR., M . D . Psychiatry Service, Veterans Administration
1. The six per second spike and wave complex (the wave and spike phantom). - - B. R. Tharp (Durham, N.C.).
The "6/see spike and wave complex" has been correlated clinically with such phenomena as seizures, headaches, syncope, abdominal pain, personality disorders and psychoses. It is reported to occur in 0.4--1 ~ of patients undergoing EEG and is more commonly seen in females, usually in the third and fourth decades. The incidence of 6/sec spike and wave discharge was determined to be 1 . 5 ~ in a group of 195 healthy adult males during routine EEG recording in which the comparison montage (which compares symmetrical scalp areas in the same channel) was used for at least 5 min of each recording. The i.v. injection of diphenhydramine (50 mg) activated the spike and wave phenomena in 10 out of 34 subjects with normal control recordings. This study suggests that the 6/sec spike and wave discharge is a normal physiologic cerebral discharge which can be provoked by the i.v. administration or a centrallyacting antihistamine. 2. Significance of obtaining four phases of sleep in children. - - H. E. Goldman (Tulsa, Okla.).
It has been well documented that in EEG work with children sleep tracings are extremely valuable. There is great difficulty in obtaining sleep tracings in the group of patients who are hyperactive whether by virtue of emotional upset or mental retardation. Various techniques have been applied to induce the 4 stages of sleep. A review of the literature would suggest that the use ofchlorpromazine for the induction of sleep rarely has been attempted. This is a study of 25 patients with tracings done under the influence of this drug during sleep and waking in order to illustrate the following points: (1) Whether or not sleep tracings are readily obtained in children with the use of
Hospital,
Durham, N.C. (U.S.A.)
chlorpromazine, the length of time of induction of sleep and the presence of undesirable side effects. (2) The production of actual natural sleep in patients with chlorpromazine, with the corresponding EEG changes thereof. (3) The fact that chlorpromazine during the tracing has had no undesirable effects on the EEG, with subsequent ease of interpretation. The findings in 25 cases, before and after chlorpromazine administration, will be presented with a discussion of abnormalities produced. 3. Some observations on the physiological mechanisms of "thalamic" pain. - - R. Musella, M. J. Short, W. P. Wilson and B. S. Nashold (Durham, N.C.).
The physiological mechanisms responsible for the diffuse burning quality of painful sensations following lesions of the thalamus are unknown. The recent observation that discharging lesions in the mesencephalon can give rise to painful sensations may account for the spontaneous paroxysms of pain suffered by these patients. However, it is possible that inhibitory feedback from the cortex and thalamus to the reticular system may be abolished, resulting in the byperesthesia occurring in these patients. In an effort to test this hypothesis we have studied twelve cats, six as acute and six as chronic preparations. In these animals radio-frequency lesions were made in the nucleus ventralis postero-lateralis (VPL) of the thalamus. Before and after the lesions evoked potentials were recorded from the reticular formation, VPL and sensory cortex after stimulation of the sciatic nerve. These evoked potentials were averaged and recorded, using a Nuclear Chicago 3100 Computer. It was observed that evoked potentials in the reticular system were abolished with acute lesions in the thalamus. If a period of 5 or more days were allowed to elapse, these potentials returned. Amplitude and wave form data, relative to the longitudinal changes occurring after lesions, are still incomplete. These
Electroenceph. clin. Neurophysiol., 1967, 23:291-293
292
SOCIETY PROCEEDINGS
will be presented in detail and their significance in regard to the phenomenon of thalamic pain discussed. 4. Electro-clinical correlations of polyphasic spike discharges. - - L. Musella, D. T. Gianturco and W. P. Wilson (Durham, N.C.). This study was carried out to investigate the findings of polyphasic discharges and spike and wave complexes appearing maximally, over the central region in children, first described by Y. Gastaut (1951) and more recently by Ricci and Scarinci (1962). In addition to the children, the study includes a number of adults with cerebral palsy, showing the typical polyphasic discharges. The clinical and electrographic records of more than 100 patients were examined. Often the electrical discharges spread from the central region to include the temporal regions. Occasionally the frontal or parieto-occipital regions were involved. They are markedly sleep- and drowsiness-sensitive. The background rhythms are usually normal. Hyperventilation and photic stimulation do not activate the records. A group of patients with high voltage polyphasic discharge limited to the occipital regions was also studied and these cases are being followed to determine whether they represent a different entity or whether they should be included in the so-called "rolandic epilepsy". Another group of patients with polyphasic discharges were seen in association with hypsarrhythmic discharges. This group is being followed also and raises interesting speculations about the prognosis. In conclusion, the polyphasic spike described by Ricci and Scarinci is not specific to rolandic epilepsy but may be seen in a variety of clinical conditions and in different age groups. 5. Further studies on reference electrodes. - - T. W. Robinson and E. O. Johnson (Birmingham, Ala.). Further studies have been made on EEG reference electrodes since our report of last year on the successful use of the various types of neck electrodes. With these "inactive" EEG reference electrodes, the E K G potential gradients were mapped around the neck and on the scalp. Since then, more simplified types of indifferent electrodes have been investigated. These are based on the principle of placing the potential from the reference electrode on both grids 1 and 2 of the amplifier. As a result of these studies, it was shown that the resistance between electrodes was independent of the inter-electrode distance and, although the resistance between the electrodes increases with time, it can change over a wide range without increasing the amount of interference. It was further indicated that if the indifferent reference electrodes are placed on the body and the exploring electrode on the scalp, both E K G and EEG changes will be displayed. However, if the reference and exploring electrodes are both placed on the scalp mainly the EEG changes will be shown. 6. The amygdala and hippocampus in olfactory aura. - O. J. Andy (Jackson, Miss.). In the present case report, the amygdaloid system is
differentiated from the hippocampal system in the elaboration of an olfactory aura. A 38-year-old white male received a blow on the right side of the skull with the butt of a rifle 6 years previous to admission. A right subdural hematoma was removed. He subsequently developed seizures characterized by an onset of "dizziness" and followed by an olfactory sensation of foul odor such as vomitus. A sense of lightheadedness and mingled thoughts developed. He occasionally heard voices which gave him commands to do things. He had periods of automatic behavior with lack of conscious awareness of his acts. EEG studies revealed a predominant right temporal focal involvement. Under local anesthesia, the right amygdala and hippocampus were exposed and bipolar electrodes placed in each structure. Bipolar electrical stimulation of the amygdala produced an after-discharge lasting 21 sec and spreading to the adjoining hippocampus. The patient became excited, restless and agitated. He complained of a foul odor and stated it was similar to his experiences during the seizures. Electrical stimulation of the hippocampus produced a discharge lasting 16 sec with minimal spread to the amygdala, and it was not accompanied by an olfactory aura. The amygdala was isolated from the hippocampus by a transverse section between the two structures and extending to the medial surface of the temporal lobe cortex. The contiguity from the amygdala to the basal forebrain structures, and that of the hippocampus to the entorhinal cortex remained intact. Following the surgical isolation of these structures, electrical stimulation of the amygdala produced a local after-discharge which lasted 20 sec and was accompanied by agitation, restlessness, and recurrence of the olfactory aura. There was no simultaneous spread of the after-discharge to the hippocampus during this episode. Stimulation of the hippocampus produced an after-discharge which did not spread to the amygdala and there was no accompanying olfactory hallucinations, restlessness or agitation. The amygdala and temporal cortical tip were excised, and the hippocampus was left intact. During a 6-month post-operative period, the patient has had no recurrent episodes of the psychomotor seizures. Conclusion: In this case, the olfactory component of the psychomotor seizure appeared to be dependent upon an after-discharge occurring in the amygdaloid system. Involvement of the hippocampal system with the after-discharge was not essential for the elaboration of the olfactory hallucination. 7. Centreneephalie seizure discharges in patients with focal hemispheral lesions. - - L. F. Stewart and F. E. Dreifnss (Charlottesville, Va.). The concept of primary and secondary bilateral synchrony is reviewed from the clinical and experimental standpoints. Five illustrative cases are presented. All of them show evidence of focal cerebral hemispheral disease and the EEG findings are those of bilaterally synchronous spike and wave discharges. It is concluded that these represent examples of secondary bilateral synchrony. Whereas the existence of primary bilateral synehrony is not denied, it
Electroenceph. clin. NeurophysioL, 1967, 23:291-293
SOUTHERN SOCIETY is emphasized that there is n o constant and reliable way to distinguish it from secondary bilateral synchrony electroencephalographically, and it seems likely that most cases of presumed primary brain-stem epilepsy are in fact examples of secoadary bilateral synchrony. From the early onset of epilepsy in these patients and others in the literature, it is concluded that the significance of the bilaterally synchronous spike and wave discharge is that it reflects a stage in the maturation of the nervous system. It is not synonymous with "centrencephalic" or with "idiopathic" epilepsy. 8.
Death?. - - H. M. Hauser and E. J. Brewer Texas).
(Houston,
A 6-week-old infant who appeared to be dead was revived with massive stimulation, but required continuous resuscitation in a Lindley Infant Respirator to prevent recurrence of cessation of all signs of life. Electroencephalographically, it was demonstrated that this was due to high brain-stem seizures with suppression of cortical activity, brief myoclonic twitchings of face and eyelids, followed immediately by isoelectricity, cardiac asystole and apnea. The brief myoclonic seizures continued while the child was well oxygenated in the respirator, but without the post-ictal isoelectricity or asystole. The seizures were controlled with Dilantin and Phenobarbital, and the child resumed spontaneous respiration on the third hospital day. At 8 months he was normal on examination and showed no signs of cerebral damage. He had remained seizure-free on Dilantin and his E E G was normal for his age. It is suggested that this may explain rare instances of misdiagnosed infant death. 9. Electroencephalograms in the 65 and over. - - H. M. Hanser (Houston, Texas).
During the first 4 months of Medicare, an increased number of private patients in the age group 65 and over
293
were studied electroencephalographically. A review of the experience in several hospital units in a large metropolitan area demonstrated most of the increase in recordings was in elderly people in old established neighborhoods. This included predominantly those aged 75 and above with obvious severe cerebral pathology and abnormal records. These people are now being hospitalized and studied more thoroughly. At this early stage in the Medicare program it was not apparent whether the EEG had proven itself beneficial in the diagnosis, management, or eventual disposition of this particular group of patients. The lack of any significant increase in normal records and only a small increase in abnormal records from the age group 65-74 indicated that the electrographic study of patients with cerebral symptoms of a minor nature has not been influenced by the new law. 10. Effect of triiodothyronine on human visual evokedpotentials. - - M. J. Short and W. P. Wilson (Durham,
N.C.). Triiodothyronine was administered to adult male volun teers for 3 days. Photically elicited occipital evoked potentials were recorded prior to and subsequent to the administration of the hormone. Consistent changes occurred in the evoked potential, characterized by increased duration and voltage of the secondary component, waves V, VI and VII, with facilitation of the rhythmic after-discharge. These findings corroborate previous work performed upon the CNS of the eat under the influence of elevated levels of thyroid hormone. In man, as in the cat, there is a relative diminution of reticular activating system influence upon the electrophysiological function of the CNS. Various signs and symptoms of hyperthyroidism are discussed as they may relate to such changes in reticular formation activity.
Flectroeneeph. clin. Neurophysiol., 1967, 23:291-293