Developments in technologic and analytical procedures applied to the study of brain electrical activity have intensified interest in this modality as a means of examining brain function. The impact of these new developments on traditional methods of acquiring and analyzing electroencephalographic activity requires evaluation. Ultimately, the integration of the old with the new must result in an accepted standardized methodology to be used in these investigations. In this paper, basic procedures and recent developments involved in the recording and analysis of brain electrical activity are discussed and recommendations are made, with emphasis on psychophysiological applications of these procedures.

Seventy-five patients meeting international diagnostic criteria for narcolepsy enrolled in a 6-week, three-period, randomized, crossover, placebo-controlled trial. Patients received placebo, modafinil 200 mg, or modafinil 400 mg in divided doses (morning and noon). Evaluations occurred at baseline and at the end of each 2-week period. Compared with placebo, modafinil 200 and 400 mg significantly increased the mean sleep latency on the Maintenance of Wakefulness Test by 40% and 54%, with no significant difference between the two doses. Modafinil, 200 and 400 mg, also reduced the combined number of daytime sleep episodes and periods of severe sleepiness noted in sleep logs. The likelihood of falling asleep as measured by the Epworth Sleepiness Scale was equally reduced by both modafinil dose levels. There were no effects on nocturnal sleep initiation, maintenance, or architecture, nor were there any effects on sleep apnea or periodic leg movements. Neither dose interfered with the patients' ability to nap voluntarily during the day nor with their quantity or quality of nocturnal sleep. Modafinil produced no changes in blood pressure or heart rate in either normotensive or hypertensive patients. The only significant adverse effects were seen at the 400-mg dose, which was associated with more nausea and more nervousness than either placebo or the 200-mg dose. As little as a 200-mg daily dose of modafinil is therefore an effective and well-tolerated treatment of excessive daytime somnolence in narcoleptic persons.

In summary, the classical sleep disorders of nocturnal enuresis, somnambulism, the nightmare, and the sleep terror occur preferentially during arousal from slow-wave sleep and are virtually never associated with the rapid-eye-movement dreaming state. Original data are reported here which indicate that physiological differences from normal subjects, of a type predisposing the individual to a particular attack pattern, are present throughout the night. The episode, at least in the case of enuresis, appears to be simply a reinforcement of these differences to a clinically overt level. A number of features are common to all four sleep disorders. These had been shown previously to be attributable to the arousal itself. New data obtained by means of evoked potential techniques suggest that these common symptoms of the confusional period that follows non-REM sleep are related to alterations of cerebral reactivity, at least of the visual system. The symptoms which distinguish the individual attack types (that is, micturition, prolonged confusional fugues, overt terror) appear to be based upon physiological changes present throughout sleep which are markedly accentuated during arousal from slow-wave sleep. These changes may in some way be related to diurnal psychic conflicts. But, to date, it has proved impossible to demonstrate potentially causal psychological activity, dreaming or other forms of mental activity, or even a psychological void in sleep just preceding the attacks. The presence of all-night or even daytime predisposing physiological changes and the difficulty in obtaining any solid evidence of a preceding psychological cause explain, no doubt, why the results of efforts to cure the disorders at the moment of their occurrence (for example, by conditioning procedures in nocturnal enuresis) have been far from satisfactory. I stress the points that the attacks are best considered disorders of arousal and that the slow-wave sleep arousal episode which sets the stage for these attacks is a normal cyclic event. Indeed it is the most intense recurrent arousal that an individual regularly experiences. The most fruitful possibilities for future research would appear to be more detailed studies of those physiological changes that predispose individuals to certain types of attacks when they undergo intense arousal or stress; the reversal of these changes by psychological or pharmacological means; and more refined investigations of the physiological and psychological characteristics of the process of cyclic arousal from non-REM sleep.

A questionnaire survey has been made of the life effects of narcolepsy in 180 patients, 60 each from North American, Asian and European populations, with 180 similarly distributed age and sex matched controls. Life-effects were attributed by the patients to the primary symptoms of excessive daytime drowsiness, sleep attacks, cataplexy, vivid hypnagogic hallucinations and sleep paralysis, and also to other frequent symptoms such as visual problems (blurring, diplopia) and memory impairment. Occupational problems were prevalent (over 75%) and included statistically significant deleterious effects upon performance, promotion, earning capacity, fear of or actual job loss RESUME: Nous avons e'tudie par questionnaire les effets sur la vie de 180 patients souffrant de narcolepsie (60 d'Amerique du Nord, 60 d'Asie et 60 d'Europe) el de 180 temoins apparilles pour age et sexe. Parmi les causes importants mentionnees par les patients, on note la somnolence diurne excessive, les attaques de sommeil, la cataplexie, les hallucinations hypnagogiques vivides et la paralysie du sommeil. D'autres symptomes frequents furenl les problemes visuels et lespertes de memoire. Des problemes au travail etaient tres frequents (75%) et significativement influent sur la performance, les promotions, la capacite a gagner, la crainte de la perte and increased disability insurance. Driving was greatly affected and patients fell asleep at the wheel more frequently (66%), had near or actual accidents from drowsiness or falling asleep at the wheel (67%), and could experience cataplexy (29%) or sleep paralysis (12%) while driving. Work or home accidents attributed to sleepiness or sleep (49%) or related to smoking (49%) were much more common in patients. There were also deleterious effects on education, recreation and personality related to the disease. Narcolepsy can produce a variety of life-effects probably more serious and pervasive than, for instance, those of epilepsy, therefore emphasizing the importance of early diagnosis and treatment. d'emploi ou la perte re'elle de I'emploi et I'assurance invalidite. La conduite d'un vehicule moteur etait souvent difficile; endormissement a la roue (66%), accidents apres somnolence (67%), cataplexie (29%) ou paralysie du sommeil (12%) avec le vehicule en marche. Les accidents a la maison ou au travail etaient egalement plus frequents, en rapport avec le sommeil (49%) ou le fait de fumer (49%). La narcolepsie eut egalement des effets nocifs sur /'education, la recreation et la personality. La narcolepsie est done apte a causer de nombreux problemes, ce qui devrait inciter a faire le diagnostic tot pour entreprendre rapidement le traitement.