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M Timsit-Berthier

Publications and source records attributed to M Timsit-Berthier.

87 records · Page 5Linked to original sources
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↗
PubMedDate not supplied

[Contingent negative variation and mental disorders].

This work, dealing with negative contingency variation (NCV) in mental patients, is in the general frame of research aiming at establishing correlations between biological phenomenons and psychic entities. The results can be examined in three different directions. 1. In the electrophysiological perspective they have individualized a series of physiological forms and brought a real nomenclature. 2. In an electro-clinical perspective, they have allowed to oppose normal curves (NCV, type I, responses to sensory stimulations type A, B, C and motor potential type N) and abnormal curves (NCV zero or type III, IV, responses type D and motor potential type P). One must however stress that this distinction is only valid if one studies adult subjects and awaken, and contributes only an index of non specific morbidity. Furthermore, considering two more electrophysiological criteria--the mode of combination of various curves and the stability of NCV--can help establishing a severity scale and modeling the above data. 3. In a physiopathological perspective, they have lead to discussing two hypotheses concerning the functional signification of prolonged NCV; one being a prolonged state of awaiting, the other a mode of particular reaction to imperative stimulation, and to demonstrate that it is not possible to consider only one and same system to explain all clinical categories. Thus, in this new area of slow cerebral potentials, as in clinical electroencephalography, is illustrated the teaching of the functional electroencephalography through the school of Paris where similar electric patterns have different significations when present in opposed psychological organisations.

Analysis of Variance↗
PubMedDate not supplied

[Study of the stress response: role of anxiety, cortisol and DHEAs].

AIM OF THE STUDY: Several studies have exhibited the psychological processes that are implied in the stress response and have shown, according to Selye's research, the participation of the hypothalamic-pituitary-adrenal axis and the major role of cortisol. The possible action of another adrenal steroïd, dehydroepiandrosterone (DHEA), is increasingly documented. The beneficial effect of the latter and his antistress role would be related to an antagonistic action to that of cortisol. The aim of our study was, first to assess biological and psychological aspects of the stress response, then to define the relationships that exist between these two processes. POPULATION AND METHODOLOGY: 40 subjects (21 women) aged 42 +/- 12 years, who consulted within a clinic of stress (CITES Prevert, Liege, Belgium) were studied. They all felt stressed but, according to DSM IV, were without mental disorders and drug free when examined. Subjects were asked to accomplish simple cognitive tasks: 1 - to distinguish two different auditory stimulations. The first one was a high-pitched sound of 1 470 Hz, which was presented unfrequently (20%). The second one, a low frequency tone of 800 Hz, was presented more frequently (80%). The interval between both stimuli was 1 s. The subject had to press a button when the rare stimulus was recognized. 2 - to extinguish a light after a warning tone of 64 dB, 50 ms and 1 000 Hz. The light, which followed one second later the tone, consisted of a series of flashes of 18 c/s that the subject had to stop by pressing a button. The purpose of this second procedure was that the subject was warned and had to prepare and anticipate the most rapid response. After that, subjects were submitted to self-evaluation psychological tests. The impact of psychosocial factors was assessed by Amiel-Lebigre life events questionnaire. Personality features and emotional response (state anxiety, related to experimental situation) were assessed by Spielberger inventory (STAI: State and Trait Anxiety Inventory). Psychological tests are practised immediately after experimental situation. Cortisol and DHEAs (dehydroepiandrosterone sulfate) were measured in blood samples taken before (t1) and after (t2) the experimental test. Cortisol was measured by radio-immunology and expressed as ng/ml of plasma. DHEAs was measured by radio-immunoassay and expressed as g/liter of plasma. RESULTS AND DISCUSSION: The majority of subjects displayed high scores of trait anxiety (37 subjects had a score>42) and life events impact (35 subjects had a score>200). These data confirmed that the subjects were fragile and were obviously stressed. In response to the cognitive tasks, that constituted for each subject a new event with which it was necessary to cope, 25 subjects exhibited high level of state anxiety (score>42) and an increase of cortisol plasmatic concentrations occurred solely in 11 persons. Ten among them were in the group of subjects which displayed a score of state anxiety>42 (p=0,0223, Chi square). Base on these data three types of stress response were identified: 1 - the experimental situation was experienced without anxiety ( psychological silence ) and without any increase in cortisol level ( biological silence ). There was no stress and these subjects were, despite their vulnerability, close to a normal health state . 2 - high emotional reaction (high level of state anxiety) was observed. This response reveals a psychological vulnerability that can be considered as the expression of a consecutive psychological distress induced by a threatening experimental situation. There were no biological manifestations ( biological silence ). 3 - high state anxiety and increased plasma cortisol levels were observed. The corresponding subjects were obviously more vulnerable. CONCLUSION: These results allow us to propose that the emergence of state anxiety is the first stress response and the primary protest . Up to a certain level, a plateau level, anxiety remains stable. Then, nature of the stress response changes and takes a biological aspect. Increased of cortisol plasma levels, the secondary protest , is observed and gives evidence of an intensified and sustained stress response. Such a gradual phenomenon is particularly reported in elevated psychological distress which is associated with loss of control. It is important to note that identical scores of state anxiety (Mann Whitney test) were observed in anxious subjects with or without rise of plasma cortisol levels. DHEAs was also implied in the stress response. The enhancement of plasma levels of DHEAs were dependent on cortisol, as shown by the close correlation between both hormones (r=0,433, p=0,0033, Spearman test). The hypothesis of an antagonism between these two hormones is based on the fact that DHEAs opposes the action of cortisol and exerts a true anticortisol effect. This antagonism might be related to a competition in their synthesis and release by the adrenal gland. In the present case, high level of anxiety (state and trait) was associated with an increase of cortisol, while low level (of anxiety) was related to an exclusive rise of DHEAs. Intermediate anxious score was observed in subjects who showed increases of both cortisol and DHEAs (p=0,0225, Kruskall Wallis test). Furthermore, a close relationship (negative correlation: Spearman test), was observed between increases in DHEAS and scores of state anxiety (r=- 0,382, p=0,06) and trait anxiety (r=- 0,0097, p=0,527). This means that the worriness and the underlying anxious ruminations and negative anticipations, which characterize trait anxiety, were less important in subjects who increased plasma DHEAs levels. In addition, emotional tension and uneasiness, which accompanies state anxiety, were also less marked. There are no studies reporting a relation between DHEA(s) and state or trait anxiety. Nevertheless, many authors have proposed a beneficial action of DHEA on the feeling of well-being. This beneficial role could be related to a double action of DHEA: a direct effect provided by its transformation into sexual hormones, an indirect one mediated by its competition with cortisol, of which the synthesis and consequently the activity decrease.

Adult↗
PubMedDate not supplied

[Recent maternity and manifestations of anxiety-depression. Epidemiological study of a population of non-consulting primiparas of the Liège region].

This study had for objective to detect the psychological morbidity of 176 non-consulting primiparas in the region of Liege using both the PSE and a sociological questionnaire. A high incidence of anxio-depressive manifestations was recorded in the month following birth (almost 27% of the cases) and their persistence at a lower rate in the 8th and 18th month. We were finally able to point out a certain number of risk factors: socioeconomic and familial conditions, somatic factors (difficult pregnancy and birth), recent psychological trauma or persistent conflict.

Adult↗
PubMedDate not supplied

[Standardized psychiatric examination according to the Wing-Cooper-Sartorius method].

The Present State Examination elaborated by Wing, Cooper and Sartorius aims at standardizing the psychiatric examination by controlling the interview technique, the definition of symptoms, and the taxinomic rationale. The method consists of two successive steps: a "human step" (evaluation of 140 symptoms) and a "computer step" (the CATEGO program, compatible with the WHO International Classification of Diseases). Besides its interest for clinical research, the Present State Examination is extremely helpful in clinical routine and in teaching. A few examples from the work done in our department are given. They concern an epidemiological study of recent mothers, a methodological reflexion on subjects presenting a borderline personality, and on a comparative study of female alcoholism.

Adolescent↗
PubMedDate not supplied

[Use of lysine-vasopressine in the treatment of post-traumatic amnesia (author's transl)].

Following experimental works on the role of vasopressine (ADH) on learning and memory process, we have treated seven subjects suffering from post-traumatic amnesia with Lysine-Vasopressine (LVP), as a nasal spray for 15 days (14 UI per day). All subjects (males, aged 20 to 63) presented a deficit for 3 years, did not follow any treatment and did not hope for any improvement. Five subjects presented a real improvement, either immediately during the treatment, or in a way more progressive some weeks after the end of the treatment. The improvement as today was evidenced by psychological tests (attention and short term visual retention tests) and by electrophysiological methods (measure of amplitude of the VCN). The improvement was mainly on general activity, motivation and capacity for social adaptation. It was associated for four subjects with a marked increases in the level of Neurophysine I. The mode of action of LVP is discussed in light of recent neurochemical and neurophysiological works.

Adult↗
PubMedDate not supplied

[Stress, anxiety and and event related potentials].

Our aim was to study the relationships between stress and anxiety with both psychological and neurophysiological (Events Related Potentials: CNV and P300) methods. The study was divided into 2 parts. In the first part, the research was carried out among 32 out-patients suffering from anxiety disorders (generalized anxiety disorders) according to DSM IV. All of them were drug free and displayed scores higher than 45 on the Spielberger Anxiety State and Trait Scale. They were compared to 40 controls paired in age and sex. The 2 groups displayed a score higher than 200 on the Amiel-Lebigre Life Events scale. In the second part, the control subjects were divided into 2 sub-groups The first one displayed scores higher than 45 (anxious controls) on the Spielberger Anxiety-State Scale while the second one displayed scores lower than 45 (non anxious controls). Two ERPs were recorded, the P300 by using the classical "Oddball" experimental paradigm in auditive modality and the Contingent Negative Variation (CNV) by using a reaction time task with warning stimulus. The results showed not only clear differences between the subjects who suffered from anxiety and the controls but also showed opposite results between anxious out-patients (anxiety disorders) and anxious controls. The non anxious controls were intermediate. While the outpatients showed a decreased P300, the group of anxious control showed an increase of this potential. The first one displayed a CNV/M1 (contingent negativity variation/early part) increase and a longest reaction time, while the second one exhibit an early CNV decrease and normally reaction time. It appears that the stress response expressed itself differently according to the psychological state and the stress situation. The behavioral and neurophysiological data will be discussed in the framework of cognitive, behavioral and psychophysiological theories.

Adult↗