Deep Sleep State Research Articles

MEMORY UNDER DIAZEPAM-MORPHINE NEUROLEFTANESTHESIA IN MALE SURGICAL PATIENTS

Sixty patients participated in an evaluation of memory during elective surgery performed under a type of neuroleptanesthesia in which diazepam and morphine were used as adjuncts to the nitrous oxide (N20)-curare technic. All patients were tested for recall of preinduction and postinduction events. In addition, patients in the experimental group heard word-pairs and neutral narrative passages through earphones at various times during operation; control patients wore the earphones but did not hear any of the taped materials. In general, patients had good recall of the preinduction period. Anesthesia was induced in all patients in approximately 2 minutes, and was accompanied by a deep sleep or amnesic state that lasted for the duration of the operative procedure. A small number (n = 9) of the patients reported vague recall of dreams, and events occurring immediately prior to (n = 2) or following (n = 5) operation. However, none reported that these recollections were in any way upsetting or distressing to them. It is concluded that the administration of a benzodiazepine tranquilizer (diazepam) and a narcotic analgesic (morphine) as adjuncts to NL.0-curare anesthesia results in a type of neuroleptanesthesia that, in addition to producing satisfactory anesthesia for major surgery, also offers considerable assurance that there will be no recollection or awareness during the operative procedure.

Relations of EEG Patterns with Arousal Level of Rat

1. Determination of EEG Patterns in SleepAn experiment was performed to determine relations of EEG patterns in natural sleep with arousal level. 6 male albino rats, 7.5 to 11 months after birth, were used. Stainless steel electrodes were implanted chronically in occipital cortex and hippocampus. EMG recordings were obtained from the neck muscle. By inspection of the polygraphic data based on EEG, EMG and behavior, 7 patterns were classified (Fig. 1). Patterns A and B indicate arousal states. Patterns C and E indicate drowsy or light sleep states. Patterns F and G indicate deep sleep states. Pattern H indicates paradoxical sleep.2. Stimulation ExperimentIn this experiment 4 rats were used. Pure tones (4000 cps, 1 sec. strong = 95 phon, weak =87 phon) were given to the animals when each EEG pattern appeared. It was assumed that tone stimulation would heighten arousal level.Fig. 3 and 4 show EEG pattern change by auditory stimuli during stimulation, post stimulation I (0-3 sec. after stimulation), post stimulation II (3-7 sec. after stimulation). Auditory stimulation changes deep sleep (F, G) and paradoxical sleep (H) EEG patterns to light sleep (C, E) patterns during stimulation or post stimulation I. But during post stimulation II, light sleep patterns changes to deep or paradoxical sleep patterns again.

Responsiveness of cat lateral geniculate at pre- and postsynaptic levels during natural sleep

Abstract Using cats carrying permanently implanted electrodes, responsiveness of the lateral geniculate body (LGB) was studied during sleep and wakefulness. The postsynaptic discharges in response to stimulation of the optic tract (OT) were smallest during light sleep and increased during deep sleep. The responses during resting wakefulness were intermediate between those during light and deep sleep. Responsiveness of the presynaptic terminals was measured by recording antidromically conducted OT spikes to stimulation of the terminals with the LGB electrodes. It is suggested that the state of deep sleep provides the LGB with a more intense presynaptic inhibition than does the state of light sleep. The deep sleep wave, a peculiar spontaneous activity seen in the LGB during deep sleep, was found to intensify phasically facilitation at the postsynaptic level and also inhibition at the presynaptic level.

NARCOSIS AS THERAPY IN NEUROPSYCHIATRIC CONDITIONS

By narcosis I mean a state of deep sleep or unconsciousness, more or less prolonged, and quite rapidly induced by means of drugs; a condition similar to the state of general anesthesia necessary for surgical operation, but not as profound. There is reported herewith the effect of narcosis in certain mental states, and its use as a therapeutic measure in the clinical management of various neuropsychiatric conditions. Before taking up the conditions in which deep sleep has been a decidedly beneficial therapy, I wish to emphasize, what seems quite unnecessary, the essential need of sleep in man and animal as well. Sleep is a biologic reaction of defense on the part of the animal organism against fatigue. Any disturbance of this natural cycle is attended with grave results. The continuous loss of sleep over a period of from five to seven days is incompatible with life. In all probability, the