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Biomedical subjects

J M Gaillard

Publications and source records attributed to J M Gaillard.

At least 127 records · Page 7Linked to original sources
PubMed1977

[Change in the mental contents in the paradoxical stage and in stage 2 under the effects of a benzodiazepine, flunitrazepam].

In some insomniacs under flunitrazepam treatment is noted on one hand a global increase of dream memories, and on the other hand an increase of dreams with unpleasant or anxious contents. The present investigation is intended first to test the hypothesis of a possible increase of mental contents in sleep outside the paradoxical phases, to account for the increase of dream memories without concomitant increase of paradoxical stage. Second it intends to investigate if the increase of unpleasant dreams may be found in the normal subject in laboratory.

Adult↗
PubMed1976

The orthodox-paradoxical sleep cycle in the rat.

Under the postulated existence of a mechanism regulating the NREM sleep- REM sleep sequence and a reset of this mechanism by long awakenings, the variability of sleep cycle in the rat was studied. Awakenings of various durations were included in the definition of sleep cycle boundaries. Results show that an intervening awakening of 1 min is close to the limit under which the same cycle seems to be resumed after the awakening and above which the previous cycle is abortive and a new cycle will start after the next sleep onset.

Animals↗
PubMed1976

A program for fitting of hypnograms and other biological data by orthogonal polynomials.

Many biological phenomenon are nonlinear and poorly approximated by linear regression. The program POLFIT calculates curvilinear regressions by fitting of orthogonal polynomials. This program, as well as two supporting programs (CORREC: disk storage, and CALCML: calculation of cumulated values of series of observations), was primarily designed for the study of the temporal organization of sleep components. They can be used as well for any other kind of biological data.

Computers↗
PubMed1976

[Sleep in the young adult studied through automatic analysis of recordings].

Our laboratory sleep polygraphic recordings are all automatically scored by a scoring system previously described. The automatic scoring reliability has already been estimated by a comparison with visual scoring. Nevertheless, it was interesting to investigate whether the picture of sleep given by this system, of a precisely defined group of subjects, was very different from that obtained by visual scoring for similar subjects in other laboratories. Therefore, we compared the results given by automatic analysis in a group of normal subjects aged 20--29 years with the results of Williams et al. (1974) for subjects of the same age. We thus mixed on purpose three sources of difference: the studied population, the laboratory and its habits, and the technique of scoring the records. This comparison showed a clear difference in the total time of sleep for men and women. This time, longer in our conditions, depended certainly on subjects and on recording conditions more than on automatic scoring. Sleep and stage latencies were not significantly different by the two scoring techniques. A difference appeared for waking latency, longer in our findings, but probably resulting from the definition of this parameter. The number of sleep cycles and their average duration were not different in the two techniques. Concerning sleep stages, stage 3 was slightly overestimated and stage 4 underestimated by automatic scoring compared with visual scoring, while there was no marked difference for the other stages. Finally, a larger number of stages are detected by the machine than by the human eye, which is probably due to the fact that the latter neglects some transitions from one stage to another when they are not important with regard to the context. Thus, apart from some differences resulting from the definition of parameters, there is a very large analogy between visual and automatic results of sleep scoring. The only effects of the latter are a slightly different assessment of the ratio of stages 3 and 4, in favour of stage 3, a larger estimate of the number of sleep stages, and a slight underestimation of REM sleep.

Adult↗
PubMed1976

Brain dopamine receptors and sleep in the rat: effects of stimulation and blockade.

A high dose of apomorphine, a stimulator of brain dopamine receptors, caused a reduction in total sleep, intermediate sleep and a delayed appearance of paradoxical sleep. With a lower dose, a small and not significant trend toward an increase of paradoxical sleep was observed. Spiroperidol, considered as a specific blocker of dopamine receptors, produced a dose-dependent increase of total sleep and a decrease of paradoxical sleep. Chlorpromazine induced a different effect, that is a clear enhancement of paradoxical sleep. Taken together, these results indicate that an activation of dopamine systems in the brain is partly involved not only in behavioral activation, but also in cortical activation of waking and paradoxical sleep. The effect of chlorpromazine on paradoxical sleep cannot be attributed to the antidopaminergic properties of this drug.

Animals↗
PubMed1976

Is insomnia a disease of slow-wave sleep?

The aim of this paper is to examine if a disturbance of slow-wave sleep may partly account for the imbalance between waking and sleep observed in insomnia. 40 normal subjects and 40 insomniacs were recorded in the laboratory. No direct interregulation appeared between total sleep and REM sleep on one hand, and between slow-wave sleep and REM sleep on the other. Slow-wave sleep, however, was linked to the waking-sleep imbalance, as low values of stages 3 and 4 were statistically associated with low total sleep duration. The reduction of slow-wave sleep could not merely be attributed to an increased pressure of wakefulness. Our results indicate that it represents probably a disturbance in itself, perhaps related in some cases to a precocious senescence of sleep, but do not account alone for all sleep disturbances.

Electroencephalography↗
PubMed1976

Benzodiazepine-induced modifications of dream content: the effect of flunitrazepam.

The purpose of this study was to investigate the effect of flunitrazepam, a benzodiazepine with strong hypnotic properties, on dream content. Eight normal subjects were studied in laboratory by the awakening technique, and the dream contents were rated by two judges according to nine scaled dimensions: unreality, participation of the dreamer, pleasantness, unpleasantness, verbal aggresivity, physical aggressivity, sexuality, sensoriality and time of reference in the dreamer's life. By comparison with placebo condition, flunitrazepam induced more unpleasantness, more verbal aggressivity, more physical aggressivity, and more sexuality in dreams. This increase of emotionally loaded contents can be related to a disinhibitory effect of this drug, and the possible involvement of dopaminergic or serotoninergic systems is discussed.

Adult↗
PubMed1976

Habituation of visually evoked responses in man: a study of its time course.

Twelve subjects were tested in a study of short-and long-term habituation of visually evoked responses to flashes with fixed and random interstimulus intervals. Long-term habituation was evalutated using blocks of 64 responses, and 'sliding' averages were calculated for estimation of the short-term habituation. Two measures of averaged evoked responses amplitude were used: N1-P2 amplitude and mean level of responses between 70 and 220 msec. A gradual decrease of amplitude of the vertex responses was observed during the first 3 min of stimulation, the greater part of this decrement occurring during the first 15 sec, with fixed interstimulus intervals. No decrement was observed with random interstimulus intervals. As the time course of long-term habituation may be influenced by fluctuations in the levels of arousal and attention, a decrement of the responses in a short period of stimulation is more likely to represent true habituation. The procedure of 'sliding' average presents some advantages over the averaging by ordinal positions used in some studies and is more satisfactory in investigations of such noncooperative subjects as psychiatric patients.

Adult↗
PubMed1976

[Seasonal rhythm of free tryptophan and nonesterified fatty acids in the blood of healthy subjects (author's transl)].

During one year, free and total tryptophan, tyrosine and non-esterified fatty acids were determined in the blood of eight healthy volunteers. No clear seasonal rhythm appeared for any of these parameters. But over this period, the following significant correlations were found: total tryptophan-free tryptophan; total tryptophan-tyrosine; free tryptophan-tyrosine. For the individuals, the quotient tyrosine-tryptophan showed to be constant during this year.

Adult↗
PubMed1975

[Formation of norapinephrine in the rat brain after administration of ((+)-erythro-3,4-dihydroxyphenylserine(author's transl)].

Fluorescence microscopy of rat brains after administration of (+)-erythro-DOPS has been studied. (+)-erythro-DOPS induced an increase of brain NE part of which was formed in the capillary walls. The slight diminution of this increase when (+)-erythro-DOPS was administered after inhibition of peripheral decarboxylase, might result from the algebraic sum of two inversely acting processes: suppression of NE synthesis in the capillary walls and enhancement of parenchymatous NE in some brain areas. (+)-erythro-DOPS enters different brain structures non specifically and NE is formed in DA and 5-HT systems, displacing the amines especially at the terminals; the NE formed by (+)-erythro-DOPS in NE systems should be rapidly catabolised. Possible pharmacological effects of (+)-erythro-DOPS administration involve consideration of the lack of topical specificity of NE formation; the displacement of 5-HT and DA; and the fact (+)-erythro-DOPS produces (+)-NE, and not naturally occurring NE.

Animals↗
PubMed1975

Effect of peripheral decarboxylase inhibition on HVA and 5HIAA in cerebrospinal fluid of depressed patients.

The effects of benserazide on the level of homovanillic acid and 5-hydroxyindoleacetic acid in CSF have been investigated in 1 manic and 11 depressed patients. Benserazide induced no change on both metabolites. This negative result supports the view that monoamine metabolites in CSF, in the absence of loading with an exogenous precursor, originate mostly from brain parenchyma, without significant contribution of the metabolism in capillary walls.

Adult↗
PubMed1975

EEG sleep studies of insomniacs under flunitrazepam treatment.

This study investigates the effect of flunitrazepam, a new benzodiazepine, on the sleep of insomniac patients under chronic treatment. Polygraphic recordings have shown that this drug decreases not only the activity of the wakefulness system, but also the activity of the synchronizing system of slow-wave sleep. The subjective feeling of improved and sounder sleep seems to be related to a decrease of wakefulness pressure as well as to a decrease of body motoricity, but not with the modification of sleep stages themselves. Flunitrazepam appears to possess some regulatory properties on REM sleep, since this stage is enhanced in patients with an initial low amount of REM sleep and decreased in those having a higher initial REM sleep. Flunitrazepam possesses potent and useful hypnogenic properties in man but does not induce physiological sleep.

Adult↗
PubMed1975

[Some problems related to the automatic interpretation of recordings of bioelectric activity in man].

The automatic interpretation of recordings of bioelectric activities in man represents a certain number of difficulties which are discussed more specially insofar as the analysis of automatic polygraphic recordings of sleep. A system of analysis specifically utilising "passe bande" filters has been used to obtain interesting results on many recordings. The interpretation itself is obtained with the help of a small computer coupled to a system of measurement and digitalisation.

Computers↗