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A 21-year-old female was first seen in 1974 for periodic hypersomnia. It had started at 13 years of age and was characterized by 4-6 days of drowsiness with megaphagia and some light psychic disorders. The attacks usually occurred at approximately 5-6 days after menstruation. Later, after an interval of oral contraception, they appeared during ovulation and increased in duration. During the periods of contraception, these attacks disappeared completely. At present (1980), the episodes are characterized by periodic hypersomnia, seen in a nocturnal polygraphic study; megaphagia has decreased, but the patient appears uncommunicative, sub-active and inexpressive when awaking in the course of the periods of somnolence. Several EEG recordings were made between 1974 and 1980, which showed few or no abnormalities during the attacks and which were normal with in the inter-ictal periods. Hormonal investigations failed to show any striking abnormality or correlation with continuous polygraphic studies. Similarity of this syndrome with the 'periodic hypersomnia and megaphagia in adolescent males' syndrome (Kleine-Levin) is discussed.

The kindling effect refers to an experimental model of epilepsy which involves an intermittent application of focal electrical stimulation to some areas of the brain. Bilateral seizures are obtained after about 15 stimulations of the amygdala in the rat. We studied the kindling effect under hyperbaric-hyperoxic conditions. In kindled rats, simulated diving significantly reduced interictal spiking. This effect was specific to the hyperoxic condition and did not occur in the normoxic-hyperbaric condition. In addition, this experiment underscored the role of stress (here, confinement stress) on the occurrence of seizures.

The authors discuss the case of four patients aged over 75 years who presented non-convulsive, but confusional status epilepticus. The EEG recordings during clinical status showed bilateral spikes of slow wave discharges in the frontal region. Following slow intravenous infusion of 10 mg of diazepam, EEG and clinical status returned quickly to normal. CT scans were always unremarkable. The ictal confusion in later life seems to be an entity, actually frequently reported in literature, which needs better description.

We report two observations of ilio-hypogastric and ilio-inguinal palsy. In both cases, an inguino-scrotal pain occurs just after low back effort. Clinically, we observed an infero-lateral 'pseudo-eventration' and trochantero-inguino-scrotal hypoesthesia in the first patient and an inguino-scrotal hypoesthesia in the second. The EMG recording shows an isolated, severe or total peripheric denervation of the inferior part of lateral abdominal muscles, associated in one case with a partial denervation of the upper lumbar paravertebral muscles. Scan shows L2 radicular asymmetry in the first patient and L1 in the second. This observation is discussed in relation to the literature.

Two E.E.G. recordings were made in a patient with human piroplasmosis (babesiosis). They showed signs of vigilance disturbances and generalized abnormalities, together with lateralization in the temporal region, on the right side in the first recording and on the left in the second one. These abnormal E.E.G. findings are reported, even though the clinical signs were not typical of babesiosis, as the biological diagnosis was certain (parasite definitely identified in the red blood cells, severe and progressive parasitic infestation), and it is impossible to evoke other aetiological elements. It is impossible to formulate a valid hypothesis, based on our present knowledge, to explain the mechanisms of this encephalic condition. We can only state the findings without prejudging its direct or indirect nature.

The authors have tried to consider EEG criteria applicable to fitness for diving. In a study of 90 professional divers, 37 (41%) displayed patterns susceptible of being interpreted as falling outside of strict normalcy. These patterns have sometimes been considered incompatible with diving, or even pathological by some authors. Considering the fact that these subjects were in good health, the value of these EEG signs is discussed in comparison with the literature. A general guideline is proposed placing subjects in three groups: fit, unfit, and questionable. In the last case, a final decision is taken in each individual case in agreement with the other medical examinations and based on the type of diving considered. Some explicit EEG criteria of definitive or temporary fitness and unfitness are proposed.

The influence of metabolic control on peripheral neuropathy was studied in a population of adult insulin-dependent diabetic patients. Motor conduction velocity (MCV), measured on the common peroneal nerve, was used as electrophysiological index of neuropathy. Following control of hyperglycaemia, rapid and significant improvement in MCV was observed in diabetics without renal or ocular complications, but not in diabetics presenting with these complications. This would suggest that peripheral diabetic neuropathy is governed by two different mechanisms and that one of these is metabolic, as it can be reversed by reinstating glucide balance.

The kindling effect is an experimental model of epilepsy which results from an intermittent application of focal electrical stimulations to certain regions of the brain. Generalized seizures are usually obtained after about fifteen stimulations of amygdala in the rat. We studied the kindling effect in hyperbaric-hyperoxic conditions. Eleven Wistar rats were stimulated daily in a caisson and all stimulations were delivered after 30 min of diving at 3 ATA of air. Diving inhibited kindling in half animals. In the others, which all presented generalised convulsions, diving produced a reduction in seizure duration, especially during the generalisation phase.

Five dogs and twelve rabbits were submitted to simulated diving at 6 ATA (compressed air) and 13-15 ATA (normoxic oxygen + nitrogen). Progressive decompressions were carried on for the first, rapid for the lasts. Motor nerve conduction velocity and nerve-muscle delays were measured. No variations could be observed neither for nerve conduction velocity nor for muscular and nerve action potentials. Nevertheless optic and electronic microscopy observations shew some nerve, neuronal and a few muscular alterations occuring during rapid decompression.

The authors, referring to 29 observed cases, review the characteristics of true renal epilepsy with regard both to attacks and to interictal periods. Their research shows that this type of epilepsy cannot be explained by any specific anatomical lesion but is probably functional and more specifically metabolic; it disappears when renal dialysis is performed. The authors accept that the factors liable to provoke this kind of epilepsy include cellular hyperhydration possibly associated with hypocalcaemia and with a genetic predisposition to convulsions. They reject the role of uraemia. This type of renal epilepsy is compared to the epileptic attacks provoked by renal dialysis.