A total of 19 episodes of epileptic laughter in 8 patients were documented by video-EEG recording. The patients were classified into two groups: 4 patients having complex partial seizures (cps) of frontal origin (group F) and 4 patients with cps of temporal origin (group T). In group F, laughter was associated with peculiar automatism characterized by a bout of vigorous struggling of the extremities and body axis (frontal automatism).The laughter ended abruptly in group F. In group T, laughter was accompanied by rather mild gestural automatism, which usually tapered off toward the end of the seizure. In both groups, the laughter began in the first half of the seizure, suggesting that the laughter was an ictal phenomenon related to the seizure origin. The laterality of seizure onset was confirmed in 6 patients; 2 in group T and 4 in gruop F. The seizures originated from the left hemisphere in 4 patients and the right in 2. In 3 patients in group F, cranial CT scans revealed organic lesions in the left hemisphere. None of these patients was able to recall a feeling of mirth associated with the laughter, indicating that the ictal laughter was merely a facial expression without accompanying emotional change in all patients.However, there is a possibility that an ictal feeling of mirth may have been experienced in group T, since all the patients in this group had ictal amnesia.

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Unverricht-Lundborg disease (ULD) is an autosomal recessive disorder char-acterized by stimulus-sensitive myoclonus, tonic-clonic seizures, slowly progressive cerebellar signs and dementia, with onset between 6 and 15 years of age. We examined two unrelated Japanese patients suspected to have ULD, a 28-year old male (case 1) and a 36-year old female (case 2) whose parents were consanguineous (first cousins). We found enlargement (750-900 bp) of the 5' flanking region of the cystatin B gene in both the patients by Southern blot analysis.Sequencing analysis revealed that a 12-mer unit CCCCGCCCCGCG repeats 2 or 3 times in healthy individuals and more than 14 times in case 1. The two cases in our report, and ULD patients in Europe showed similar clinical and neurophysiological features;recessive inheritance, onset between 6 and 15 years of age, stimulus-sensitive myoclonus, slowly progressive cerebellar signs and dementia, giant somatosensory evoked potential (SEP) and characteristic electroencephalographic patterns (3-5 Hz generalized spike and wave, photosen-sitivity). We therefore suggest that the identification of mutant genes encoding cystatin B in patients suspected to have ULD not only contributes to the diagnosis in Japanese patients with ULD but also might contribute to the development of genetic studies in ULD.

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Near infrared spectroscopy (NIRS) appears to be a safe, noninvasive technique useful in the EEG laboratory.NIRS has been used for continuous monitoring of changes in blood and tissue oxygenation of the whole brain. We report our observa-tions of changes in local cerebral oxygenation in temporal lobe epilepsy.
Eleven patients (four men, seven women;average age31.9years) including two patients after surgical treatment were selected by identifing temporal lobe atrophy and lateralizing the epileptic focus, by means of MRI, SPECT and EEG. Using NIRS (Hamamatsu Photonics Co., Hamamatsu, Shizuoka, Japan), changes in cerebral blood and tissue of oxygenated haemoglobin (HbO₂) and deoxygenated haemoglobin (HbR) produced by hyperventilation (HV) were measured in both the temporal region with the atrophy and the contralateral temporal region.
In both temporal regions, HbO₂values decreased from baseline (at start of HV) after the end of HV, but there was no difference between temporal region with atrophy and contralateral temporal region. However, in nine cases except two cases after surgical treatment, there was difference between them when HV ended.HbR values changed from baseline, but there was no difference between temporal region and contralateral region. Because of results, it is suggested that NIRS may be useful for one of supplementary diagnosis of temporal lobe epilepsy, but it is necessary to investigate further.

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The authors report a quantitative autoradiographic analysis of benzodiazepine receptors using the partial inverse agonist ¹²⁵I-iomazenil in surgically resected tissues of 27 patients with intractable partial epilepsies. Pathological diagnosis of these tissues was; 14 mesial temporal sclerosis (MTS), 8 dysembryoplastic neuroepithelial tumor (DNT), 4 cortical dysplasia (CD) and 1 angioma. In MTS patients, the density of benzodiazepine receptors decreased in CAl, CA3 and CA4. The layers of gyrus dentatus were displaced with a thick and high density band. These findings were similar to simultaneous GABA-A stain findings. The decrease of receptor in each hippocampal structure highly correlated to the degree of cell loss in CAl, CA3 and CA4. The receptors were almost absent in the main lesions of DNT and angioma, and showed irregular distributions in the cortex around these lesions. The receptor den-sities of CD were parallel to Palmini's pathological grading. Nine cases were analyzed using ¹²³I-iomazenil SPECT before surgery after obtaining informed consent. Eight of them revealed marked low accumulations in the areas corresponding to the epile-ptogenic foci. We conclude that our results support histochemically the clinical availa-bility of ¹²³I-iomazenil SPECT as a non-invasive technique for detecting the changes in benzodiazepine receptor densities in patients with partial epilepsies.

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A 6-year-old girl developed self-induced pattern-sensitive epilepsy. There is no family history of epilepsy. At 6 years, she developed myoclonic jerks mainly on voluntary viewing of patterns such as her mother's vertically-striped clothes and a mesh of screen windows. Neither spontaneous nor photosensitive seizures occurred. Her seizures remained myoclonic except two generalized tonic-clonic seizures at ages 7 and 11. After the age of 10, the seizures occurred exclusively by self-induction. Interictal EEGs showed generalized spike-wave complexes but no photosensitivity. Ictal EEGs showed a generalized polyspike-wave complex. Computed tomography on the head revealed no abnormalities. Her self-induced seizures were controlled with valproate by the end of her 12th year. However, she had obsessive interest in patterns until age 12. She did not have other behavioral problems, but her intelligence quotient was 71 on the Kyoto Scale of Psychological Development. Her visual memory was especially poor in the test. She is now 13 years old and still on valproate. She is seizure-free and shows no more obsessive behavior toward patterns.

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We reported a surgical case of intractable frontal lobe epilepsy whose epile-ptogenic focus was remote from and independent of the structural brain lesion. The patient was twenty-six-year-old female suffering from intractable seizures for eight years. Three types of seizure were identified; (1) sudden vocalization during sleep, (2) incomprehensible words following speech arrest and (3) adversive seizure after simple partial attack of left upper limb followed by a secondary generalization. In magnetic resonance image a structural lesion was found in the anterior part of the supplementary motor area in the right madial frontal lobe. Scalp EEG demonstrated that the ictal events started from the right parietal area. Epileptogenic focus was determined at the hand area of the right motor cortex by video-EEG monitoring and functional mapping with chronic subdural electrodes. The lesion was totally removed and pathological diagnosis was astrocytoma grade 2. Since the epileptogenic focus was independent of the lesion, multiple subpial transection was performed to the focus and its surrounding area following tumor removal. The seizure disappeared after the surgery. Surgical strategy for treating patients with structural brain lesion associated with intractable epilepsy was discussed.

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