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H Mantanus

Publications and source records attributed to H Mantanus.

At least 19 recordsLinked to original sources
PubMed1991

Comparison of adinazolam, amitriptyline, and diazepam in endogenous depressive inpatients exhibiting DST nonsuppression or abnormal contingent negative variation.

Adinazolam, a triazolobenzodiazepine that has an action similar to antidepressants in several pharmacological tests, was compared with amitriptyline and diazepam in endogenous depressive inpatients exhibiting dexamethasone suppression test non-suppression and/or abnormal contingent negative variation. Three parallel groups of 22 patients received in double-blind conditions either adinazolam (60-90 mg/day), amitriptyline (150-225 mg/day), or diazepam (30-45 mg/day) over a 4-week period, with weekly assessments by the Hamilton Rating Scale for Depression. Results showed significant superiority of amitriptyline over diazepam on total Hamilton depression scores. On the endogenomorphy subscale, amitriptyline induced significantly better improvement than both diazepam and adinazolam, whereas both amitriptyline and adinazolam exhibited significantly better antidepressant efficacy on the core symptoms of depression. Moreover, the dropout rate for inefficacy after 2 weeks of treatment was higher in the diazepam group. Taken together, these findings suggest that adinazolam has an antidepressant efficacy intermediate between amitriptyline and diazepam. Adinazolam was, however, much better tolerated than amitriptyline, and produced significantly fewer anticholinergic side effects.

Adult↗
PubMed1988

Inhibitory influence of oxytocin infusion on contingent negative variation and some memory tasks in normal men.

A double-blind study combining electrophysiological and psychometrical approaches was carried out to investigate the central effects of an intravenous oxytocin (OT) infusion in normal men. Contingent negative variation (CNV) was selected as the measure of central cognitive evoked potential, and the psychometric tests measured mood, vigilance and memory. OT infusion induced a significant decrease of CNV amplitude and an increase of post-imperative positive potentials in vertex derivations. A similar effect was still evidenced one week after treatment in frontal derivations, suggesting a long time effect of OT on human brain. No significant influence of OT on mood or vigilance tests was apparent; only one item of a memory test revealed a significant impairment of some mnesic performances. These observations provide new electrophysiological arguments supporting a central action of peripheral OT administration in man.

Adult↗
PubMed1988

[Modifications of contingent negative variation (CNV) induced by oxytocin infusion].

The central effects of an intravenous infusion of oxytocin (OT), 3,680 mIU in 45 min, were investigated in 20 male volunteers in a double-blind study combining an electrophysiological and a psychometrical approach. The electrophysiological approach consisted in the simultaneous recording of the CNV (Fz-A1 and Cz-A1) and the spontaneous EEG (bipolar P3-P4) recording on which was carried out an FFT analysis. On the other hand, various psychometric tests allowed to assess memory (Rey's tests), attention (K-T test) processes and mood changes (visual analogue scales). Within the hour following the infusion, OT induced a significant decrease of CNV amplitude and an increase of the post-imperative positive component at Cz-A1. A similar effect was still observed one week later, but was more marked at Fz-A1. Neither mood nor attention tests evidenced any significant effect of OT. Only one item of the memory test PRM (item 4) revealed a significant impairment after OT infusion. There were no subjective effects reported. These observations provide new electrophysiological arguments supporting a central action of peripheral OT administration in man. This action, which may be characterized as an acceleration of CNV "habituation" is the opposite of the one described with vasopressin.

Brain↗
PubMed1988

[Relationship between dexamethasone suppression test and contingent negative variation in major depressive patients].

We tried to relate two different indexes sensitive to the perturbations induced by major depression: the Dexamethasone Suppression Test or DST (Caroll, 1982) and the Contingent Negative Variation (CNV). The question was whether abnormalities in cortisol levels, following dexamethasone would enlight the modifications observed in CNV parameters and other electrophysiological indexes (EEG spectrum, reaction time). In 61 major depressive patients, 29 being DST-non-suppressors, we calculated differences in electrophysiological variables according to DST suppression or not, but we were not able to evidence significant differences between the groups. However, there were correlations between log-transformed levels of cortisol and on the one hand, CNV slope (r = -0.34, P less than 0.03) and on the other hand, reaction time (r = 0.45, P less than 0.01). Correlations between electrophysiological variables appeared in the sole suppressors group (e.g. CNV amplitude and alpha rythm reactivity; post-imperative variation and percent beta of the EEG spectrum). These results underline the complementary aspect of the two methods.

Adult↗
PubMed1985

Sleep and wake after benzodiazepine hypnotics: a 20-hour EEG comparison of lormetazepam and flunitrazepam.

In an electropharmacokinetic study, the effects of lormetazepam and flunitrazepam were compared by the means of a sleep EEG and waking EEG during the following daytime. At a 1-week interval, 6 normal subjects received at random either 2 mg lormetazepam or 2 mg flunitrazepam in a double-blind, crossover fashion. Sleep EEG was recorded throughout the night; 6-min EEG samples were recorded every hour during 10 hours on the following daytime for spectral analysis. Night sleep after flunitrazepam showed lower Stage IV sleep than after lormetazepam. During daytime, only flunitrazepam induced an increased percentage of beta 2 frequencies, which remained above baseline up to 10 hours after awakening, indicating a prolonged impregnation time. This study permitted comparison of the relative intensity and duration of these two benzodiazepines: lormetazepam appeared to be a short-acting hypnotic while flunitrazepam displayed longer modification of the brain electrical activity.

Adult↗
PubMed1984

[Is there a correlation between the phases of CNV and the power spectrum of the EEG?].

In 14 volunteers, the relationships between CNV and EEG power spectrum were studied during 3 periods of 1 sec: before S1, between S1 and S2, and after S2. We noted first a relation between CNV amplitude and EEG spectrum over the 3 periods: there was an inverse correlation for the alpha band, and a direct correlation for the beta band. We also observed a direct, strong correlation (r = 0.94) between CNV slope and alpha band reactivity during the S1-S2 interval, but this held only for subjects showing a decrease of alpha activity during the S1-S2 interval. There was no correlation at all between the positive phase (post-S2) of the CNV and EEG. These results are discussed in terms of functional states of the brain influencing CNV development, as well of the various modes of activation and reactivity at the individual level that modify the relationships between CNV and EEG.

Adolescent↗
PubMed1984

Self-reports of anxiety level and EEG changes after a single dose of benzodiazepines. Double-blind comparison of two forms of oxazepam.

A new formulation of oxazepam especially designed to increase the speed of absorption and eliminate the need to use water (freeze-dried dosage formulation; FDDF) was compared in double-blind and crossover conditions with the standard tablets of the same compound. 5 inpatients with generalized anxiety disorder received at 1-week intervals a single 30 mg dose of one of the compounds. Every 8 min for 96 min after drug intake, they completed a battery of visual analogue scales and had an EEG recording with computerized spectral analysis. Results showed a significantly more rapid onset of activity of FDDF oxazepam for both the self-reports of anxiety level (p less than 0.005) and the specific beta 2 EEG changes (p less than 0.0001), which were significantly correlated (r = -0.73; p less than 0.01). Moreover, all patients rated FDDF oxazepam as having faster onset of action in clinical change than regular tablets (p less than 0.05). This study shows the value of visual analogue scales, pharmaco-EEG, and crossover design in well-selected anxious inpatients in substantiating clinical differences between anxiolytic pharmacotherapies.

Adult↗
PubMed1983

[Relation between fast EEG rhythms and contingent negative variation].

The experiments were done to investigate the relationships between activation level and contingent negative variation (CNV). Two groups of subjects, differing in their level of cortical arousal, were recorded with eyes open (OE, N = 17) or eyes closed (CE, N = 40). Beta activity, CNV, electro-oculogram, reaction time and heart rate were studied. In the CE group, beta activity and CNV were not significantly correlated. In the OE group, CNV was slightly extended with a higher amplitude and a higher post-imperative negativity when beta activity was higher; heart rate was also significantly correlated with beta activity in this group. The results are discussed as a function of the existence of two neurophysiological mechanisms of generation and regulation of CNV.

Adult↗
PubMed1982

[Quantified EEG and CNV changes during inhalation of nitrous oxide].

The present study constitutes an approach to the action mechanisms of nitrous oxide (N2O) by assessing both the subjective effects induced by the inhalation of this anaesthetic gas, and their electrophysiological correlates, i.e., spontaneous EEG, analyzed by a Fourier algorithm, AEP and CNV. The experiment was conducted single blind in 9 volunteers under 3 recording conditions: inhalation of air, of a mixture of 25% N2O--75% O2, and of a mixture of 50% N2O--50% O2. A latin-square design was used. Polymorphic effects of N2O were evidenced on behaviour and on CNS: some of the behavioural manifestations could evoke a depression of SNC: muscle relaxation with difficulty of motor initiation, psychomotor slowing, slower EEG with diminution of the percent alpha component and increase in the percent theta and delta, loss of amplitude of both exogenous (N1) and endogenous (P300) components of the AEP. Conversely, other manifestations were observed that are compatible with an activation of the CNS: increase of sensory perceptions, appearance of perceptual illusions, maintenance of a high CNV amplitude and lengthening of its duration. This dual effect of N2O suggests a dissociative action at the different levels of the CNS.

Adult↗
PubMed1982

Action of lysine-vasopressin on human electroencephalographic activity. Night sleep pattern, auditory evoked potential, contingent negative variation.

This study is an investigation of the central effects of vasopressin in man, as this hormone proved able to modify learning processes in animals and was applied successfully to post-traumatic, amnesic patients. Electrophysiological techniques were used to assess the effects of lysine-vasopressin (LVP) given by nasal spray (7 and 14 IU) on night sleep pattern (12 subjects), auditory evoked potentials (AEP; 26 subjects), and contingent negative variation (CNV; 26 subjects). Night sleep EEG was not modified to a great extent: in particular REM sleep did not undergo any change after LVP. Nor were AEPs modified, either in the 6-hour period following drug administration or 1 week after; CNV, however, reacted in a significant manner 6 h after drug intake, and the modifications were still present after 1 week. LVP did not affect CNV amplitude itself but its evolution through time, as CNV habituation was prevented. Such effects are discussed with regard to the neurochemical mechanisms of vasopressin action and CNV genesis.

Administration, Intranasal↗
PubMed1981

A correlation study of contingent negative variation, reaction time, and EEG power spectrum in control and psychopathological populations.

Contingent negative variation (CNV), reaction time (RT), and EEG power spectrum were measured in a group of 27 neurotics and 26 controls subjects, male and female, aged 18 to 38. CNV was recorded with a 1 sec interstimulus interval and averaged over 48 trials. Two spectral analyses of the EEG were performed, the first during the 1 sec period preceding S1 (spontaneous EEG), the second during the S1-S2 interval (activated EEG). For each group of subjects, we calculated the correlations between four measures of CNV amplitude, RT duration, and the relative powers of the delta, theta, alpha and beta activities during spontaneous and activated EEG. In neurotic subjects there was an absence of correlation between the pre- and post-imperative segments of the CNV, and between early CNV amplitude and per cent alpha power. Both groups shared in common strong correlations relating CNV amplitude and RT length, on the one hand, and the different components of the EEG spectrum, on the other hand, Principal component analysis applied to the pooled data revealed different factors for CNV and EEG parameters, suggesting independence of the neurophysiological mechanisms implied in the two phenomena.

Adolescent↗
PubMed1981

[Inversion of the polarity of contingent negative variation during falling asleep (author's transl)].

In 25 subjects repeated examination of contingent negative variation (S1 - S2 = 1 sec) under relatively unconstrained experimental conditions (simple, monotonous task, long recording sessions with eyes closed) favorized drowsiness and falling asleep. These periods of low vigilance level, observed in 7 subjects, are characterized by: (1) a global reduction in spontaneous EEG, measured by a diminution in the alpha/theta + delta index (FFT on bipolar leads P3--P4); (2) an inversion in alpha reactivity in the S1 - S2 interval, which, instead of diminishing, tends to augment 'paradoxically'; and (3) an inversion in the polarity of the CNV, which can reach a positive value as high as + 15 to + 20 microV. These electrophysiological phenomena are not accompanied by significant modifications in reaction time. The results are interpreted as the translation of an active 'internal inhibition' process, induced by repetition of monotonic stimuli. They are compared with animal data obtained by MARCZYNSKI and SHERRY (1972) and SKINNER and YINGLING (1977).

Adult↗
PubMed1981

A study of psychological and endocrine variables on 14 patients treated by chronical haemodialysis.

In 13 patients suffering from renal dysfunction and treated by chronic haemodialysis, the mnemic functions appeared within the limits of normality and there was no positive correlation between blood levels of neurophysines and free cortisol. On the other hand, a negative correlation was found between levels of neurophysine I and items 3 and 5 of the memory test PRM. This negative result indicates that in haemodialyzed patients a discrepancy may exist between blood levels of neurophysines and vasopressin release, or that there is no direct relationship between plasma and CSF concentrations of such hormones.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

[Comparative study of the CNV and the quantitative EEG during a simple motor task (author's transl)].

The purpose of this study was to evaluate CNV amplitude variability and its degree of covariance with the spontaneous EEG (quantified by FFT algorithm) and the reaction time. 14 healthy male subjects made from atypical for one hour, and they had to keep their eyes closed. Recordings were during this period. CNV experimental paradigm was performed (S1--S2 = 1500 msec). The major findings of this study were that: 1) the CNV amplitude progressively decreased during the first part of the test (habituation) and then tended to stabilize. While not correlated with the vigilance index of spontaneous EEG (alpha/theta + delta index) the CNV amplitude was significantly related to the alpha reactivity index (% alpha of spontaneous EEG--% alpha of the S1--S2 EEG), 2) the CNV slope (calculated by drawing two points situated at 600 msec and 1400 msec after S1) showed significant relationship to both these EEG indices and the reaction time. These data are discussed in terms of Cooper's distinction between "scopeutic" and "categoric" processes (1978) and in terms of the Tecce model of the CNV (1972).

Adult↗