Electrophysiology of the Interictal-Ictal Transition in Humans

  • Michael R. Sperling


Since the discovery of the spike in the EEG by Gibbs and colleagues in 1935, cerebral electrical activity has been the subject of intensive investigation in the study of epilepsy. The focus of most investigators has been upon abnormalities seen in the interictal state, the examination of seizures being limited to relatively few specialized laboratories. Early studies of the transition from the interictal to the ictal state characterized amplitude and frequency changes in the EEG, and while attention was paid to underlying mechanisms, in humans, a decided emphasis has been placed upon localization of a seizure focus for purposes of resective surgery (1,27,29,31,55,67,92). Key features of the ictal state, compared with the interictal state, are the capacity for development of self-sustaining discharges and spread to other cortical and subcortical areas. The purpose of this discussion is to review the electrophysiologic features in focal epilepsy of the transition from interictal to the ictal state.


Temporal Lobe Temporal Lobe Epilepsy Ictal Onset Seizure Focus Complex Partial Seizure 
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  1. 1.
    Ajmone-Marsan, C. Electrographic aspects of epileptic neuronal aggregates. Epilepsia 2: 22 - 38, 1961.PubMedCrossRefGoogle Scholar
  2. 2.
    Ajmone-Marsan, C. and Ralston, B. The epileptic seizure-its functional morphology and diagnostic significance. A clinical-electrographic analysis of metrazol induced attacks. Springfield, Ill: Chas. C. Thomas, 1957.Google Scholar
  3. 3.
    Ajmone-Marsan, C. and Zivin, L. Factors related to the occurrence of typical paroxysmal abnormalities in the EEG records of epileptic patients. Epilepsia 11: 361 - 381, 1970.CrossRefGoogle Scholar
  4. 4.
    Angeleri, F., Giaquinto, S., Marchesi, G. Registrazione elettroclinica delle crisi temorali e scariche intercritiche nell sonno notturno. Rev. Neurol. 40: 321 - 327, 1970.Google Scholar
  5. 5.
    Ayala, G., Dichter, M., Gumnit, R., Matsumoto H., Spencer W. Genesis of epileptic interictal spikes-New knowledge of cortical feedback systems suggests a neurophysiological explanation of brief paroxysm. Brain Res. 52: 1 - 17, 1973.PubMedCrossRefGoogle Scholar
  6. 6.
    Babb, T. and Brown, W. Neuronal, dendritic, and vascular profiles of human temporal lobe epilepsy correlated with cellular physiology in vivo. In: Advances in Neurology. A. Delgado-Escueta, A. Ward, D. Woodbury, R. Porter (eds). Vol. 44:949-966, 1986.Google Scholar
  7. 7.
    Babb, T., Carr, P., Crandall, P. Analysis of extracellular firing patterns of deep temporal lobe structures in man. Electroencephalogr. Clin. Neurophysiol. 34: 247257, 1973.Google Scholar
  8. 8.
    Babb, T. and Crandall, P. Epileptogenesis of human limbic neurons in psychomotor epileptics. Electroencephalogr. Clin. Neurophysiol. 40: 225 - 243, 1976.Google Scholar
  9. 9.
    Babb, T., Lieb, J., Brown, W., Pretorius, J., Crandall P. Distribution of pyramical cell density and hyperexcitability in the epileptic human hippocampal formation. Epilepsia 25: 721 - 728, 1984.PubMedCrossRefGoogle Scholar
  10. 10.
    Babb, T., Wilson, C., Isokawa-Akesson, M. Firing patterns of human limbic neurons during SEEG and clinical temporal lobe seizures. Electroenceph. Clin. Neurophysiol. 66: 467 - 482, 1987.PubMedCrossRefGoogle Scholar
  11. 11.
    Bancaud, J, Talairach, J., Bonis, A., Bordas-Ferrer, M. Anomalies EEG inercritiques bitemporales asynchrones dans les epilepsies unilaterales (a propos dune epilepsie dorigine tumorale). Rev. Neurol. 121: 369 - 379, 1969.PubMedGoogle Scholar
  12. 12.
    Bancaud, J. Riber, M., Chagot D. Origine comparee des paroxysmes de pointes infra-cliniques spontanees dans lepilepsie. Rev. EEG Neurophysiol. 5: 63 - 66, 1975.Google Scholar
  13. 13.
    Beaussart, M. and Faou, R. Evolution of epilepsy with rolandic paroxysmal foci: a study of 324 cases. Epilepsia 19: 337 - 342, 1978.PubMedCrossRefGoogle Scholar
  14. 14.
    Bengzon, A., Rasmussen, T., Gloor, P., et al. Prognostic factors in the surgical treatment of temporal lobe epileptics. Neurology 18: 717, 1968.PubMedCrossRefGoogle Scholar
  15. 15.
    Blum, B. and Posener, L. A stochastic analysis of interictal epileptiform activity. Confin. Neurol. 26: 519 - 531, 1965.PubMedGoogle Scholar
  16. 16.
    Brazier, M. Spread of seizure discharges in epilepsy: anatomical and electrophysiological considerations. Exp. Neurol. 36: 263 - 272, 1972.PubMedCrossRefGoogle Scholar
  17. 17.
    Brazier, M. Electrical seizure discharges within the human brain: the problem of spread. In: Epilepsy: Its Phenomena in Man. M. Brazier (ed). New York: Academic Press, pp. 153 - 170, 1973.Google Scholar
  18. 18.
    Brown, W. Structural substrates of seizure foci. In: Epilepsy: Its Phenomena in Man. M. Brazier (ed). New York: Academic Press, pp. 339 - 375, 1973.Google Scholar
  19. 19.
    Buser, P., Bancaud, J., Talairach, J. Depth recordings in man in temporal lobe epilepsy. In: Epilepsy: Its Phenomena in Man. M. Brazier (ed). New York: Academic Press, pp. 67 - 97, 1973.Google Scholar
  20. 20.
    Calvin, W., Ojemann, G., Ward A. Human cortical neurons in epileptogenic foci: comparison of interictal firing patterns to those of epileptic neurons in monkeys. Electroencephalogr. Clin. Neurophysiol. 34: 337 - 351, 1973.PubMedCrossRefGoogle Scholar
  21. 21.
    Calvin, W., Sypert, G., Ward, A. Structural timing patterns within bursts from epileptic neurons in undrugged monkey cortex. Exp. Neurol. 21: 535 - 549, 1973.CrossRefGoogle Scholar
  22. 22.
    Cooper, R., Winter, A., Walter, W. Comparison of subcortical, cortical and scalp activity using chronically indwelling electrodes in man. Electrocephalogr. Clin. Neurophysiol. 18: 217 - 228, 1965.CrossRefGoogle Scholar
  23. 23.
    Crandall, P. Developments in direct recordings from epileptogenic regions in the surgical treatment of partial epilepsies. In: Epilepsy: Its Phenomena in Man. M. Brazier (ed). New York: Academic Press, pp. 339 - 375, 1973.Google Scholar
  24. 24.
    Crandall, P., Walter, R., Rand R. Clinical applications of studies on stereotactically implanted electrodes in temporal-lobe epilepsy. J. Neurosurg. 21: 827 - 840, 1963.CrossRefGoogle Scholar
  25. 25.
    Daly, D. Circadian cycles and seizures. In: Epilepsy: Its Phenomena in Man. M. Brazier (ed). New York: Academic Press, pp. 216 - 235, 1973.Google Scholar
  26. 26.
    Dichter M. and Ayala G. Cellular mechanisms of epilepsy: a status report. Science 237, 157 - 164, 1987.PubMedCrossRefGoogle Scholar
  27. 27.
    Engel, J., Crandall, P., Rausch, R. The partial epilepsies. In: The Clinical Neurosciences, Roger Rosenberg (ed). New York: Churchill Livingston, Vol. II. pp. 1349 - 1380, 1983.Google Scholar
  28. 28.
    Falconer, M. and Kennedy, W. Epilepsy due to small focal temporal lesions with bilateral spike discharging foci: a study of seven cases relieved by operation. J. Neurol. Neurosurg. Psychiatr. 24: 205 - 212, 1963.CrossRefGoogle Scholar
  29. 29.
    Gastaut, H. The Epilepsies: Electro-clinical Correlations. Springfield, Ill: Charles C. Thomas Publisher, p. 149, 1954.Google Scholar
  30. 30.
    Gastaut, H. and Gibbs, E. Atlas of Electroencephalography, Vol. 2, Epilepsy. Reading, Mass: Addison-Wesley Publishing Co., 1952.Google Scholar
  31. 31.
    Geiger, L. and Harner, R EEG patterns at the time of focal seizure onset. Arch. Neurol. 35: 276 - 286, 1978.PubMedCrossRefGoogle Scholar
  32. 32.
    Gibbs, F., Davis, H., Lennox, W. The electroencephalgram in epilepsy and in impaired states of consciousness. Arch. Neurol. Psychiatr. 34: 1133 - 1148, 1935.CrossRefGoogle Scholar
  33. 33.
    Gibbs, F. and Gibbs, E. Atlas of Electroencephalography, Ed 2. Vol. 2. Cambridge, Mass: Addison-Wesley, 1952.Google Scholar
  34. 34.
    Gloor, P. Contributions of electroencephalography and electrocorticography to the neurosurgical treatment of the epilepsies. In: Advances in Neurology, Neurosurgical Management of the Epilepsies. D. Purpura. J. Penry, R. Walter (eds). Vol. 8, New York: Raven Press, pp. 59 - 105, 1975.Google Scholar
  35. 35.
    Gloor, P. Electroencephalography and the role of intracerebral depth electrode recordings in the selection of patients for surgical treatment of epilepsy. In: Advances in Epileptology. XVth Epilepsy International Symposium. R. Porter, et al (eds). New York: Raven Press, pp. 433 - 437, 1984.Google Scholar
  36. 36.
    Goldensohn, E. and Purpura, D. Intracellular potentials of cortical neurons during focal epileptogenic discharges. Science 139: 840 - 842, 1963.PubMedCrossRefGoogle Scholar
  37. 37.
    Goldring, S. and Gregorie, E. Surgical management of epilepsy using epidural recordings to localize the seizure focus. J. Neurosurg. 60: 457 - 466, 1984.PubMedCrossRefGoogle Scholar
  38. 38.
    Gotman, J., Ives, J., Gloor, P., Olivier, A., Quesney, L. Changes in interictal EEG spiking and seizure occurrences in humans. Epilepsia 23: 432 - 433, 1982.Google Scholar
  39. 39.
    Hahn, J. and Sellers, M. Surgical techniques for relief from seizures. Cleve. Clin. Q. 5: 307 - 311, 1984.Google Scholar
  40. 40.
    Hartman, E., Colasanti, B., Craig, C. Epileptogenic properties of cobalt and related metals applied directly to cerebral cortex of rat. Epilepsia 15: 121 - 129, 1974.PubMedCrossRefGoogle Scholar
  41. 41.
    Hess, R. Localized abnormalities. In: Handbook Electroencephalography and Clinical Neurophysiology. A. Remond (ed). Elsevier, Amsterdam, Vol. 11B, Section V, pp. 88 - 115, 1976.Google Scholar
  42. 42.
    Hill, D. The electroencephalographic concept of psychomotor epilepsy: A summary. Compts. Rendus IV Cong.. Neurol. Internat., Paris, Vol. 1: 27 - 33, 1949.Google Scholar
  43. 43.
    Isokawa-Akesson, M., Babb, T., Wilson, C. Physiology of hippocampal neurons in humans and lower mammals. In: Fundamental Mechanisms of Human Brain Function: Opportunities for Direct Investigation in Association with the Surgical Treatment of Epilepsy. J. Engel, et al. (eds). 1987a.Google Scholar
  44. 44.
    Isokawa-Akesson, M., Wilson, C., Babb, T. Structurally stable burst and synchronized firing in human amygdala neurons: auto-and cross-correlation analyses in temporal lobe epilepsy. Epilepsy Res. 1: 17 - 34, 1987b.PubMedCrossRefGoogle Scholar
  45. 45.
    Ishijima, B., Hori, T., Yoshimasu, N., Fukushima, T., Hirakawa, K., Sekino, H. Neuronal activities in human epileptic foci and surrounding areas. Electroencephalogr. Clin. Neurophysiol. 39: 643 - 650, 1975.PubMedCrossRefGoogle Scholar
  46. 46.
    Jasper, H. Report of committee on methods of clinical exam in EEG. EEG Clin. Neurophysio1. 10: 370 - 375, 1958.CrossRefGoogle Scholar
  47. 47.
    Jensen, I. Temporal lobe epilepsy. Etiological factors and surgical results. Acta Neurol. Scandinay. 53: 103 - 118, 1976.Google Scholar
  48. 48.
    Jensen, I. Temporal lobe epilepsy. Types of seizures, age and surgical results. Acta Neurol. Scandinay. 53: 335 - 357, 1976.CrossRefGoogle Scholar
  49. 49.
    Johnston, D. and Brown, T. Mechanisms of neuronal burst generation. In: Electrophysiology of Epilepsy. P. Schwartzkroin and H. Wheal (eds). London: Academic Press, pp. 277 - 302, 1984.Google Scholar
  50. 50.
    King, D., So, E., Marcus, R., Gallagher, B. Techniques and applications of sphenoidal recording. J. Clin. Neurophysiol. 3: 51 - 65, 1986.Google Scholar
  51. 51.
    Komatsu, Y., Toyama, K., Maeda, J., Sakaguchi, H. Long-term potentiation investigated in a slice preparation of striate cortex of young kittens. Neurosci. Lett. 26: 269 - 274, 1981.PubMedCrossRefGoogle Scholar
  52. 52.
    Kopeloff, N., Chusid, J., Kopeloff, L. Epilepsy produced in Macaca mulatta with commerical aluminum hydroxide. Electroencephalogr. Clin. Neurophysiol. 6: 303 - 306, 1954.PubMedCrossRefGoogle Scholar
  53. 53.
    Lange, H., Lieb, J., Engel, J., Crandall, P. Temporal-spatial patterns of pre-ictal spike activity in human temporal lobe epilepsy. Electroencephalogr. Clin. Neurophysiol. 56: 543 - 555, 1983.PubMedCrossRefGoogle Scholar
  54. 54.
    Lieb, J., Engel, J., Gevins, A., Crandall, P. Surface and deep EEG correlates of surgical outcome in temporal lobe epilepsy. Epilepsia 22: 515 - 538, 1981.PubMedCrossRefGoogle Scholar
  55. 55.
    Lieb, J., Walsh, G., Babb, T., Walter, R., Crandall, P. A comparison of EEG seizure patterns recorded with depth electrodes in patients with temporal lobe epilepsy. Epilepsia 17: 137 - 160, 1976.PubMedCrossRefGoogle Scholar
  56. 56.
    Lieb, J., Hogue, K., Skomer, C., Song, X. Interhemispheric propagation of human mesial temporal lobe seizures: a coherence/phase analysis. Electroencephalogr. Clin. Neurophysiol. 67: 101 - 119, 1987.PubMedCrossRefGoogle Scholar
  57. 57.
    Lieb, J., Woods, S., Siccardi, A., Crandall, P., Walter, D., Leake, B. Quantitative analysis of depth spiking in relation to seizure foci in patients with temporal lobe epilepsy. Electroencephalogr. Clin. Neurophysiol. 44: 641 - 663, 1978.PubMedCrossRefGoogle Scholar
  58. 58.
    Lombroso, C. Sylvian seizures and midtemporal foci in children. Arch. Neurol. 17: 52, 1967.PubMedCrossRefGoogle Scholar
  59. 59.
    Matsumoto, H. and Ajmone-Marsan, C. Cortical cellular phenomena in experimental epilepsy: Interictal manifestations. Exp. Neurol. 9: 286 - 304, 1964.PubMedCrossRefGoogle Scholar
  60. 60.
    Matsumoto, H. and Ajmone-Marsan, C. Cortical cellular phenomena in experimental epilepsy: Ictal manifestations. Exp. Neurol. 9: 305 - 326, 1964.PubMedCrossRefGoogle Scholar
  61. 61.
    Mazars, Y. Interpretation du phenomene dextinction dans la phas initiale de crises focales corticales. Rev. Neurol. 82: 520 - 522, 1950.PubMedGoogle Scholar
  62. 62.
    Fetsche, H., Prohaska, O., Rappelsberger, P., Vollmer, R., Kaizer, A. Cortical seizure patterns in multidimensional view: the information content of equipotential maps. Epilepsia 15: 439 - 463, 1974.CrossRefGoogle Scholar
  63. 63.
    Prince, D., Connors, B., Benardo, L. Mechanisms underlying interictal-ictal transition. In: Advances in Neurology: Status Epilepticus. A. Delgado-Escueta, C. Wasterlain, D. Treiman, and R. Porter (eds). New York: Raven Press, 34:177187, 1983.Google Scholar
  64. 64.
    Prince, D. and Connors, B. Mechanisms of epileptogenesis in cortical structures. Ann. Neurol. 16 (suppl): 59 - 64, 1984.CrossRefGoogle Scholar
  65. 65.
    Prince, D. and Wong, R. Human epileptic neurons studied in vitro. Brain Res. 210: 323 - 333, 1981.PubMedCrossRefGoogle Scholar
  66. 66.
    Racine, R. and McIntyre, D. Mechanisms of kindling: a current view. In: The Limbic System. B. Doane and K. Livingston (eds). New York: Raven Press, pp. 109 - 121, 1986.Google Scholar
  67. 67.
    Ralston, B. The mechanism of transition of interictal spiking foci into ictal seizure discharges. Electroencephalogr. Clin. Neurophysiol. 10: 217 - 232, 1958.PubMedCrossRefGoogle Scholar
  68. 68.
    Ralston, B. and Papatheodorou, C. The mechanism of transition of interictal spiking foci into ictal seizure discharges. Part II, Observation of man. Electroencephalogr. Clin. Neurophysiol. 12: 297 - 304, 1960.PubMedCrossRefGoogle Scholar
  69. 69.
    Rasmussen, T. Cortical excision for medially refractory focal epilepsy, Proceedings of the Hans Berger Centenary Symposium. New York: Churchill Livingston, pp. 227 - 239, 1974.Google Scholar
  70. 70.
    Rasmussen, T. Surgical treatment of complex partial seizures: results, lessons, and problems. Epilepsia 24 (suppl.) S65 - S76, 1983.PubMedCrossRefGoogle Scholar
  71. 71.
    Rayport, M. and Waller, H. Technique and results of micro-electrode recording in human epileptogenic foci. Electroencephalogr. Clin. Neurophysiol. (Suppl.), 25: 143 - 151, 1967.Google Scholar
  72. 72.
    Reid, S. and Sypert, G. Chronic models of epilepsy. In: Electrophysiology of Epilepsy. P. Schwartzkroin and H. Wheal (eds). London: Academic Press, pp. 138 - 151, 1984.Google Scholar
  73. 73.
    Rovit, R., Gloor, P., Henderson, L. Temporal lobe epilepsy: a study using multiple basal electrodes. I. Description of method. Neurochirurgia 3: 6 - 19, 1960.PubMedGoogle Scholar
  74. 74.
    Schwartzkroin, P. Hippocampal slices in experimental and human epilepsy. In: Advances in Neurology. A. Delgado-Escueta. A. Ward, Jr., D. Woodbury, R. Porter (eds). Vol. 44:991-1010, 1986.Google Scholar
  75. 75.
    Schwartzkroin, P. and Haglund M. Spontaneous rhymthic synchronous activity in epileptic human and normal monkey temporal lobe. Epilepsia 27: 523 - 533, 1986.PubMedCrossRefGoogle Scholar
  76. 76.
    Schwartzkroin, P. and Knowles W. Intracellular study of human epileptic cortex: in vitro maintenance of epileptiform activity. Science 223: 709 - 712, 1984.PubMedCrossRefGoogle Scholar
  77. 77.
    Schwartzkroin, P. and Prince D. Cellular and field potential properties of epileptogenic hippocampal slices. Brain Res. 147: 117 - 130, 1978.PubMedCrossRefGoogle Scholar
  78. 78.
    Schwartzkroin, P., Turner, D., Knowles, W., Wyler, A. Studies of human and monkey epileptic neocortex in the vitro slice preparation. Ann. Neurol. 13: 249257, 1983.Google Scholar
  79. 79.
    Sherwin, I. Interictal-ictal transition in the feline pencillin epileptogenic focus. Electroencephalogr. Clin. Neurophysiol. 45: 525 - 534, 1978.Google Scholar
  80. 80.
    Spencer, S. Depth electroencephalography in selection of refractory epilepsy for surgery. Ann. Neurol. 9: 207 - 214, 1981.CrossRefGoogle Scholar
  81. 81.
    Sperling, M. and Engel, J. Jr. Electroencephalographic recording from the temporal lobes: a comparison of ear, anterior temporal and nasopharyngeal electrodes. Ann. Neurol. 17: 510 - 513, 1985.PubMedCrossRefGoogle Scholar
  82. 82.
    Sperling, M. and Engel J. Jr. Sphenoidal electrodes. J. Clin. Neurophysiol. 3: 67 - 73, 1986.PubMedCrossRefGoogle Scholar
  83. 83.
    Sperling, M., Mendius, J., Engel J. Jr. Mesial temporal spikes: a simultaneous comparison of sphenoidal, nasopharyngeal, and ear electrodes. Epilepsia 27: 8186, 1986.CrossRefGoogle Scholar
  84. 84.
    Sperling, M., Lieb, J., Engel J. Jr., Crandall, P. Independent auras in patients with complex partial seizures. Epilepsia 27: 628, 1986.CrossRefGoogle Scholar
  85. 85.
    Sypert, G., Oakley, J., Ward A. Single unit analysis of seizures in neocortex. Exp. Neurol. 28: 308 - 325, 1970.PubMedCrossRefGoogle Scholar
  86. 86.
    Sypert, G. and Ward, A. The hyperexcitable neuron: Microelectrode studies of the chronic epileptic focus in the intact, awake monkey. Exp. Neurol. 19: 104, 1967.PubMedCrossRefGoogle Scholar
  87. 87.
    Talairach, J. and Bancaud, J. Stereotactic exploration and therapy in epilepsy. In: Handbook of Clinical Neurology, P. Vinken, G. Bruyer (eds). North-Holland, Amsterdam, Vol. 15: 758 - 782, 1974.Google Scholar
  88. 88.
    Talairach, J., David, M., Tournoux, P., et al. Atlas des noyaux gris centraux-atlas danatomie stereotaxique. Masson, Paris, 1957.Google Scholar
  89. 89.
    Talairach, J., David, M., Tournous, P. Lexploration chirurgicale stereotaxique du lobe temporale dans lepilepsie temporale. Masson, Paris, p. 136, 1958.Google Scholar
  90. 90.
    Van Buren, J., Ajmone-Marsan, C., Mutsuga, N., et al. Surgery of temporal lobe epilepsy. In: Advances in Neurology. Neurological Management of the Epilepsies. D. Purpura, J. Penry, R. Walter (eds). Vol. 8, New York: Raven Press, pp. 155 - 196, 1975.Google Scholar
  91. 91.
    Walker, A. Convulsive activity. Quart. Phi Beta Pi, 47: 108 - 115, 1950.Google Scholar
  92. 92.
    Walter, R. Tactical considerations leading to surgical treatment of limbic epilepsy. In: Epilepsy: Its Phenomena in Man. M. Brazier (ed). New York: Academic Press, pp. 99 - 119, 1973.Google Scholar
  93. 93.
    Ward, A. Physiological basis of chronic epilepsy and mechanisms of spread. In: Advances in Neurology: Status epilepticus. A. Delgado-Escueta, C. Wasterlain, D. Treiman, R. Porter (eds). New York: Raven Press, 34:189-199, 1983.Google Scholar
  94. 94.
    Wieser, H. Electroclinical Features of the Psychomotor Seizure. Fischer, Stuttgart, 1983.Google Scholar
  95. 95.
    Wieser, H. and Yasargil, M. Selective amygdalohippocampectomy as a surgical treatment of mesiobasal limbic epilepsy. Surg. Neurol. 17: 445 - 457, 1982.PubMedCrossRefGoogle Scholar
  96. 96.
    Wieser, H., Bancaud, J., Talairach, J., Bonis, A., Szikla, G. Comparative value to spontaneous and chemically and electrically induced seizures in establishing the lateralization of temporal lobe seizures. Epilepsia 20: 47 - 59, 1979.PubMedCrossRefGoogle Scholar
  97. 97.
    Wilson, C., Isokawa-Akesson, M., Babb, T., Wang, M., Engel J. Temporal lobe neuronal excitability in complex partial epilepsy. In: Proceedings of the 16th Epilepsy International Congress, 1985.Google Scholar
  98. 98.
    Wyler, A., Burchiel, K., Ward, A. Chronic epileptic foci in monkeys: correlations between seizure frequency and proportion of pacemaker epileptic neurons. Epilepsia 19: 475 - 483, 1978.PubMedCrossRefGoogle Scholar
  99. 99.
    Wyler, A., Ojemann, G., Ward, A. Neurons in human epileptic cortex: correlation between unit and EEG activity. Ann. Neurol. 11: 301 - 308, 1982.PubMedCrossRefGoogle Scholar
  100. 100.
    Wyler, A. and Ward, A. The alumina monkey model. In: Electrophysiology of Epilepsy. P. Schwartzkroin and H. Wheal (eds). London: Academic Press, pp. 277 - 302, 1984.Google Scholar
  101. 101.
    Zivin, L. and Ajmone-Marsan, C. Incidence and prognostic significance of epileptiform activity in the EEG of non-epileptic subjects. Brain 91: 751 - 778, 1968.PubMedCrossRefGoogle Scholar

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© Springer Science+Business Media New York 1988

Authors and Affiliations

  • Michael R. Sperling
    • 1
  1. 1.Department of NeurologyThe Graduate Hospital University of PennsylvaniaPhiladelphiaUSA

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