Biomedical subjects

B Saletu

Publications and source records attributed to B Saletu.

At least 91 records · Page 5Linked to original sources

PubMed1995

[Sleep apnea as a risk factor].

Sleep apnea and snoring are widely discussed as risk factors for internal and neurological diseases. The prevalence of snoring in an Austrian population survey is about 27.2% (males 36.5%, females 18.9%), and that of apnea (respectively irregularity and/or cessation of breathing) about 8.5% (31% of all snorers). Clinical symptoms like naps, daytime sleepiness, unquiet sleep, hypertonia, headache in the morning and psychological symptoms may be characteristics of sleep apnea. They should lead to further diagnosis and removal of this risk factor for ischemic heart disease and stroke.

Adolescent↗

PubMed1995

[A new method for testing the psychopharmacologic pupil oscillation hypothesis following administration of a nootropic substance].

Recently a new, precise and economical method for measuring central nervous activation in psychopathological groups was presented. By means of this procedure, the ¿psychopharmacological pupillary oscillations hypothesis¿ after administration of the nootropic compound bifemelane (CAS 90293-01-9) was examined in oder to assess pharmacologically induced changes in central activation. Before calculating the Fourier analysis, blinks have to be identified and eliminated by means of a new technique, which is called ¿smoothing¿. After application of bifemelane, a marked improvement of symptoms caused by cerebro-vascular disorders was reported. 18 subjects (7 females and 11 males), aged between 60 and 80 years, with a neurological and psychic age-adequate state, from whom a written, informed consent was obtained, participated voluntarily in the study. A placebo-controlled and double-blind design were administered in an interval of 8 days in cross-over design. The study, which also included measurement of noopsychic and thymopsychic changes, was carried out before and in the 2nd, 4th, 6th and 8th hour after application of the substances. In the slow frequency band, after application of bifemelane, an increase of activation (higher amplitudes) could be observed, which lasted from the 2nd to the 4th hour. However, differences between bifemelane and placebo did not reach the level of statistical significance. In faster frequencies, a reduction of the height of the amplitudes was found. Regarding the total spectrum, in the 2nd hour a moderate increase of activation could be demonstrated.

Aged↗

PubMed1994

Discrimination between demented patients and normals based on topographic EEG slow wave activity: comparison between z statistics, discriminant analysis and artificial neural network classifiers.

The topographic distributions of absolute delta and theta powers were used to classify demented patients and normals by means of z statistics, discriminant analysis and artificial neural networks (NN). The data were taken from two psychopharmacological studies in mildly to moderately demented patients (111 and 96 patients for studies I and II, respectively) and from 56 normal healthy controls. All patients were diagnosed according to DSM-III criteria and were free of medication for at least 2 weeks. The NN used was a strictly layered feed-forward network with complete connections. The z-transformed absolute power values in the combined delta and theta frequency range at 17 electrodes, recorded in a 3 min vigilance-controlled EEG with eyes closed, were used as input. After having trained the NN successfully by backpropagating of errors, the generalization test with independent data results in a classification performance of 90% determined by "relative operating characteristic" analysis. The NN out-performed z statistics and discriminant analysis. This high percentage of correct classifications may justify the development of further application of NNs based on topographic EEG data.

Aged↗

PubMed1994

Placebo-controlled trial of the xanthine derivative propentofylline in dementia.

Treatment of dementing illnesses is still unsatisfactory and agents that might have potential for improving cognitive functions are therefore under extensive investigation. Over a 3-month period a multicenter, double-blind, placebo-controlled, parallel-group study was conducted in 190 patients with dementia to examine whether administration of the xanthine derivative propentofylline at 0.9 g/d might either improve cognition or slow the progression of the disease. Improvement in performance on the Gottfries-Brane-Steen scale (GBS) and in at least two of eight psychometric assessments were defined a priori as the primary efficacy measures. The total scores on the GBS decreased in both the propentofylline and the placebo groups, with improvement however being significantly (p < 0.0001) higher in the propentofylline group. The mean scores in the Mini-Mental State Examination increased significantly (p < 0.05) in both groups, but the increase was significantly (p < 0.02) higher in the propentofylline-treated group. In contrast, psychometric assessments and the cognitive difficulties scale failed to demonstrate a therapeutic benefit of propentofylline after three months. Performance in these categories showed a significant (p < 0.05) improvement for the propentofylline-treated patients and for the placebo-treated patients, but was comparable for both groups. Thus, in spite of the positive results in GBS, the efficacy of propentofylline could not be established according to the definition of the primary efficacy measures. The clinical parameters, however, can be positively influenced by propentofylline. In addition, the results indicate that patient performance can already be enhanced if subjects are required to engage in cognitive tasks.

Aged↗

PubMed1994

BMS-181168 for protection of the human brain against hypoxia: double-blind, placebo-controlled EEG mapping studies.

In a double-blind, placebo-controlled, cross-over trial, the antihypoxidotic properties of BMS-181168 (previously BMY 21502)--a 1-[[1-[2-(trifluoromethyl)-4-pyrimidinyl]-4-piperidinyl]methyl]-2- pyrrolidinone alleviating impairment of learning and memory in the animal--were studied utilizing EEG mapping under an experimental hypoxic hypoxidosis. The latter was induced by a fixed gas combination of 9.8% oxygen (O2) and 90.2% nitrogen (N2) (found at 6000 m altitude), which was inhaled for 23 minutes under normobaric conditions by 16 healthy male volunteers (aged 23-35 years, mean 27.2 years). After an adaptation session, they received in randomized order at weekly intervals oral single doses of placebo, or of 100 mg, 200 mg, and 400 mg BMS-181168. Evaluation of blood gases (PO2, PCO2, SO2), adverse events, and EEG mapping was carried out prior to drug administration and 2, 4, 6 and 8 hours post-drug, on each occasion under normoxic and transient hypoxic conditions. Hypoxemia was controlled by drawing arterialized capillary blood samples from the earlobes after hyperemization of the latter (after 0, 14, and 23 minutes of hypoxic gas inhalation) and by oximetry. After 23 minutes of inhalation, analysis showed a drop in PO2 from 98 to 48 mm Hg, in PCO2 from 41 to 31 mm Hg, and in SO2 from 97 to 80%. Descriptive statistical analyses of EEG mapping data demonstrated under hypoxia/placebo conditions an increase in delta/theta activity and a decrease in alpha activity as well as a slowing of the delta/theta centroid and an increase in the alpha and beta centroid, which suggests a marked deterioration in physiological vigilance.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Pharmacokinetic and -dynamic studies with a new anxiolytic, suriclone, utilizing EEG mapping and psychometry.

1. In a double-blind, placebo-controlled, cross-over study, acute pharmacokinetic, neurophysiological and psychotropic effects of suriclone, a new cyclopyrrolone derivative, were investigated and compared with alprazolam. 2. Fifteen normal young volunteers received randomized oral single doses of placebo, 0.1, 0.2 and 0.4 mg suriclone as well as 1 mg alprazolam as reference compound. Investigations were carried out before and 1, 2, 4, 6 and 8 h after drug administration. 3. Pharmacokinetic investigations by radioimmunoassay showed a dose-dependent fast rise of plasma concentrations with a peak at 1 h and a rapid decline thereafter. Both the Cmax and the AUC values exhibited a linear relationship to dose. 4. EEG brain mapping demonstrated significant CNS effects of both compounds, characteristic for tranquillizers (increase of beta, decrease of alpha and increase of delta activity; attenuation of total power and acceleration of the centroid, i.e. centre of gravity frequency). When compared with alprazolam, suriclone exerted less sedative effects. 5. Time-efficacy calculations showed the pharmacodynamic peak effect of suriclone from the 2nd to the 4th hour, and of alprazolam in the 1st hour. Dose-efficacy calculations showed that the most pronounced CNS changes occurred after 1 mg alprazolam, followed by 0.4, 0.2 and 0.1 mg suriclone. 6. Psychometric investigations demonstrated no significant effects after the two lower doses of suriclone, while 0.4 mg and 1 mg alprazolam induced a decrement both in noopsychic and thymopsychic variables seen after higher doses of anxiolytic sedatives. Psychophysiology (critical flicker fusion, pupillometry, and skin conductance measures) pulse rate, systolic and diastolic blood pressure remained unchanged. 7. Psychophysiology (critical flicker fusion, pupillometry and skin conductance measures) showed differential dose-dependent effects. Pulse rate, systolic and diastolic blood pressure remained unchanged. Anxiolytic-characteristic side-effects (tiredness, drowsiness, etc.) occurred predominantly after the highest doses 0.4 mg suriclone and 1 mg alprazolam.

Administration, Oral↗

PubMed1994

Insomnia in generalized anxiety disorder: polysomnographic, psychometric and clinical investigations before, during and after therapy with a long- versus a short-half-life benzodiazepine (quazepam versus triazolam).

Within a double-blind, comparative study on the effects of the long-half-life benzodiazepine (BDZ), quazepam, and the short-half-life BDZ, triazolam, on clinical symptomatology, sleep and anxiety of 45 patients with insomnia based on a mild to moderate generalized anxiety disorder (GAD) (ICD-9 code: 307.42-1, 300,0; ASDC-APSS-Code: A.2.a), we compared, in a first step at baseline, drug-free polysomnographic and psychometric data of 22 patients recorded in the laboratory (L-group) and 21 patients recorded by the Oxford Medilog 9000 system at home (H-group) with those of normal controls. Sleep efficiency, total sleep time, wake within total sleep period (middle insomnia) and wake before buzzer (late insomnia) were significantly deteriorated in both patient groups as compared with controls, while sleep induction time only differed significantly in home recordings. Regarding sleep architecture, stage (S)2 was reduced, S3 and S4 increased in the H-group only, while no intergroup differences were seen in S1, SREM and REM latency. Subjective sleep quality was reduced in both patient groups, but not awakening quality. Psychometric tests in the morning demonstrated for the noopsyche, only a significantly deteriorated psychomotor activity in both patient groups. In the thymopsyche, evening well-being and mood in the morning were reduced in both the L- and H-group, affectivity and morning well-being only in the H-group. The psychopharmacological part of the study was completed by 40 patients (there were 4 drop-outs in the triazolam, 1 in the quazepam group). They were treated after 1 week placebo with either 15-30 mg (median 15 mg) quazepam or 0.25-0.5 mg (median 0.25 mg) triazolam for 4 weeks, and thereafter for 2 weeks with placebo. Anxiety (rated by HAMA and SAS) improved significantly with both drugs and remained improved throughout 2 weeks post-drug placebo, with quazepam being slightly superior to triazolam. Polysomnography demonstrated a shortened sleep onset only after quazepam. Sleep efficiency improved after acute administration of both drugs, but the improvement was maintained by quazepam only (tolerance development with triazolam). Rebound insomnia was observed only in the 1st post-triazolam placebo night (significant intergroup difference based on confirmatory testing). S2 increased, S3 + S4 decreased under and after quazepam, which represents a normalization in home-recorded GAD patients. S1 decreased with both drugs, SREM only under quazepam. Subjective sleep quality behaved very similarly to objective sleep efficiency. Awakening quality improved after acute therapy with both drugs, somatic complaints only with quazepam.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1994

Clinical, EEG mapping and psychometric studies in negative schizophrenia: comparative trials with amisulpride and fluphenazine.

Based on recent quantitative EEG findings of increased slow activity in negative schizophrenia indicating organicity, it was hypothesized that neuroleptics decreasing delta/theta activity should be beneficial for schizophrenics with predominantly negative symptoms. Thus, a double-blind, clinical, psychometric and neurophysiological study was carried out in 40 hospitalized patients with unproductive schizophrenia (mean age: 31 years; ICD diagnoses: 295.0, 295.1 and 295.6) who were treated randomly either with the benzamide amisulpride (AMI; n = 19) or low doses of fluphenazine (FLU; n = 21). In the first 2 weeks the daily doses were 50 mg AMI or 2 mg FLU, respectively, from the third week on up to the sixth week 100 mg AMI and 4 mg FLU. Clinical evaluations, psychometry and EEG mapping were performed on day 1 (hours 0 and 4--acute effect), on day 14 (hour 0--subacute effect) and on day 42 (hours 0 and 4--chronic and superimposed effects). Three AMI patients discontinued therapy prematurely because of productive symptoms (days 14, 28 and 35), while in the FLU group 2 patients dropped out due to depressive symptoms (days 21, 28), 1 due to productive symptoms (day 35), 1 due to ineffectiveness (day 28), and 1 because of an akinetic crisis (day 6). Statistical evaluation demonstrated a significant improvement in the AMDP apathy and Andreasen SANS score in both groups with the patients remaining severely ill as rated by the CGI. FLU-treated patients needed significantly more anticholinergic medication than the AMI-treated group. Psychometric evaluation showed in regard to the noopsyche significant improvement after subacute, chronic and superimposed AMI, while FLU-treated patients showed significant improvement only after subacute treatment. AMI was significantly superior to FLU at the hours 0 and 4 of day 42. The thymopsyche improved after subacute, chronic and superimposed administration of both compounds with a significant superiority of AMI on days 14 and 42 (4 h postdrug). EEG mapping showed a decrease of delta/theta and increase of beta activity as well as an acceleration of the centroid after acute and superimposed AMI on day 42 as compared with baseline; FLU patients exhibited a decrease of delta/theta activity and an acceleration of the total centroid too, while alpha activity was augmented and beta activity tended to be reduced. Our study demonstrated that, in addition to the new benzamide AMI, FLU in low doses may also be regarded as a neuroleptic with activating properties and may be utilized in the treatment of schizophrenics with predominantly negative symptoms.

Adult↗

PubMed1994

Automatic sleep-spindle detection procedure: aspects of reliability and validity.

The paper describes a reliable and valid method for the automatic detection of sleep spindles in whole night polygraphy. The recording of a multi-channel EEG during sleep polysomnography was performed in 10 healthy volunteers aged 20-35 years. This objective method should improve the time-consuming and subjective visual evaluation by increasing the accuracy and allowing the calculation of quantitative variables (i.e., frequency and amplitude), thereby facilitating scientific work with quantitative data. An important part of the method is the treatment of artifacts (i.e., muscle and spindle-like alpha activity). Compared to hardware solutions, our software method has the advantage of higher flexibility in regard to artifact identification and usual spindle definitions.

Adult↗

PubMed1994

[Epidemiology of sleep disorders in Austria].

UNLABELLED: Epidemiologic data on sleep disturbances in Austria were collected for the first time in March/April 1993 in a representative inquiry ( SAMPLE: n = 1000, 471 males, 529 females). 26% of the subjects reported sleep disturbances which were mostly chronic (21% had suffered from sleep disturbance for more than one year). The incidence of sleep disturbances increased with age, namely 13% in 14-30 year-old subjects, 22% in 31-50 year-old ones and 41% in subjects over 50. 7% suffered from disturbances in sleep initiation, i.e., they had a sleep latency of over 30 minutes. 19% of them had difficulties in getting to sleep at least once a week. Disturbances in maintaining sleep were reported by 28% of subjects, 56% of them needing longer than one hour to get back to sleep. 30% suffered from daytime sleepiness, 43% of the subjects were impaired by their sleep disturbances in some way, but only 34% had consulted their doctor.

Adolescent↗

PubMed1994

[A new method for measuring central activation: fourier analysis of pupillary oscillations in depressed patients].

While the changes in pupillary size during wakefulness and drowsiness are easy to understand, the origin of pupillary oscillations is quite mysterious. Waves of spontaneous pupillary constriction and dilation accompany periods of increasing sleepiness and spontaneous arousal. Lowenstein et al. (1963) demonstrated that in the dark, the pupils of young normal alert subjects show waves of dilatation and contraction lasting from about 4 to 40 s and measuring up to 0.5 mm. Furthermore, superimposed fast and very extensive oscillations were observed. The first described oscillations seemed to reflect central nervous activation. Therefore we analysed pupillary oscillations during the recording period of static pupillometry (described by the authors in 1992) which lasted for 25.6 s. Before calculating the Fourier analysis, blinks have to be identified and eliminated by means of a new technique which is called "smoothing". Using the Fourier analysis, the spectrum was divided into 5 frequency bands (0.0-0.2; 0.21-0.4; 0.41-0.60; 0.61-0.8; 0.81-1 Hz). We were also interested in the total spectrum. In order to demonstrate utilisation of the new technique, 146 male and female depressed patients (ICD-Diagnosis 296.1, 296.3, 296.1, 296.3 + 300, respectively, 300.4, 301.1, 296.1, 296.3 + 290, respectively), aged between 18 and 45 years, were investigated by means of pupillometry, followed by analysis of pupillary oscillations. The whole group of depressive patients who received antidepressive medication was compared with 64 healthy subjects of similar age to demonstrate differences in the frequency bands.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Topographic mapping of EEG during sleep.

Topographic aspects of all night sleep EEG were investigated in 10 healthy volunteers (age 20-35 years). EEG brain maps showed an increase of delta power from stage 1 to 4, a decrease of alpha power most pronounced parieto-occipitally and a slowing of the dominant alpha frequency. Differences of EEG power in different sleep stages (as compared to wakefulness) are displayed topographically. Analysis of the course of stage 2 showed an increase of delta power and a decrease of theta power in the first sections of the night, and an increase of beta power later in the night.

Adult↗

PubMed1993

Influence of partial sleep deprivation on the secretion of thyrotropin, thyroid hormones, growth hormone, prolactin, luteinizing hormone, follicle stimulating hormone, and estradiol in healthy young women.

The influence of partial sleep deprivation during the second half of the night on the secretion of thyroid stimulating hormone (TSH), thyroxin (T4), free T4 (fT4), triiodothyronine (T3), prolactin (PRL), growth hormone (GH), luteinizing hormone (LH), follicle stimulating hormone (FSH), and estradiol (E2) was investigated in 10 healthy young women. Blood samples were drawn at hourly intervals over a 64-hour period (i.e., 3 consecutive days and nights). During night 2, all subjects were awakened at 1:30 a.m. During partial sleep deprivation, TSH concentrations increased significantly and remained elevated throughout the following day. Levels of T4, fT4, and T3 were enhanced during the partial sleep deprivation hours only, and changes in these hormones seemed to be independent of TSH. PRL levels decreased, LH and E2 concentrations increased, and GH and FSH secretion remained unchanged during partial sleep deprivation. This pattern of change of different endocrine axes during partial sleep deprivation resembles those seen after total sleep deprivation, suggesting that similar neurochemical changes are induced by both forms of antidepressant therapy. The late evening GH peak occurred almost exclusively before the onset of sleep. Partial sleep deprivation did not influence the chronobiological profiles of any of the hormones investigated. The chemical changes underlying these alterations are speculated to involve enhancement of central norepinephrine and dopamine activity with a concomitant increase in the activity of the sympathetic nervous system.

Adult↗

PubMed1993

The effect of biologically-active light on the noo- and thymopsyche and on psychophysiological variables in healthy volunteers.

The study was carried out to show how bright light affects intellectual mnestic performance alertness, mood and psychophysiological variables in order to understand the mechanism of bright light which is still unclear. 15 healthy normal volunteers (8 males, 7 females) aged 22-34 years (mean 27) participated in the study. Exposure to bright light (2500 lux) or dim light (500 lux) was intermittent for 4 h between 9 a.m. and 5 p.m. Psychometric investigations for assessment of noopsychic variables, such as attention and concentration on the one hand, and thymopsychic variables, such as drive, on the other hand, as well as flexibility and psychophysiological measurements were carried out before, as well as 1, 2, 4, 6 and 8 h after baseline. As compared to the dim-light condition, subjects who were exposed to biologically-active light showed an improvement of noopsyche in the 6th and 8th hour. Also, the subjective thymopsyche revealed an improvement lasting for the whole investigation period. Psychophysiological measurements reflected an improvement of central and autonomous activation, which was parallel to the improvement of cognition and of well-being. However, biologically-active light did not affect flexibility.

Adult↗

PubMed1993

Acute effects of the novel antidepressant venlafaxine on cognitive event-related potentials (P300), eye blink rate and mood in young healthy subjects.

Venlafaxine is a novel non-tricyclic antidepressant, which preclinically has demonstrated serotonin, norepinephrine, and dopamine reuptake inhibiting effects. In this study acute effects of single oral doses of placebo, 12.5 mg, 25 mg, and 50 mg venlafaxine on event-related potentials (ERPs), eye blink rate and mood were studied in 16 healthy subjects. ERPs were investigated in an auditory odd-ball paradigm before as well as 3 h after each drug intake. In addition to 17 EEG leads, vertical and horizontal EOGs were recorded. After EOG minimization and visual artefact rejection the peak latencies of the spatial average were determined by an automatic procedure. The applied methods of data acquisition, artefact processing, objective component determination and statistical analysis were successful in describing acute effects of venlafaxine on ERPs in normals. N1 and P2 latencies were not affected. An increase in P2 amplitude in the relevant central and frontal regions was seen, reflecting some effect on automatic information processing. Stimulus evaluation time was not affected, as P300 latency remained unchanged. P300 amplitude was not affected at the relevant central and parietal region. Blink rate was not changed. By means of the adjective checklist a dose-dependent decrease of "extroversion" and "high spirits" and an increase of "introversion" was observed. Our findings suggest that venlafaxine affects human information processing less than would be expected from the more centrally inhibiting classical antidepressants.

Adult↗

PubMed1993

Treatment of the alcoholic organic brain syndrome: double-blind, placebo-controlled clinical, psychometric and electroencephalographic mapping studies with modafinil.

In a double-blind study 40 abstinent hospitalized male patients with an alcoholic organic brain syndrome (OBS; ICD 9: 291.2) were treated for 6 weeks with either placebo or 200 mg modafinil b.i.d. Modafinil (CRL 40476) is a vigilance-promoting, putative central alpha 1-adrenergic agonist with a pharmacological profile quite different from that of amphetamine. Clinical investigations demonstrated that the spontaneous remission of the alcoholic OBS was augmented and accelerated by modafinil, which was found significant as compared with placebo by confirmatory statistics in the target variable, the Clinical Global Impression scale. The drug was well tolerated. Psychometric tests revealed significant improvement of the noopsyche after modafinil as compared with placebo, while the thymopsyche and psychophysiological measurements were not affected. Electroencephalographic mapping showed significant differences between the central effects of modafinil and placebo indicating an improvement of vigilance under modafinil. Typical vigilance-promoting properties were seen after acute drug administration, were less evident before the morning dose after chronic treatment but re-occurred after super-imposed daily drug administration. Thus, our clinical, psychometric and neurophysiological investigations in alcoholic OBS patients demonstrated a therapeutic effect of modafinil in the early phase of abstinence.

Adult↗

PubMed1993

Restriction to a limited set of EEG-target variables may lead to misinterpretation of pharmaco-EEG results.

The number and types of target variables quantified from the spectrally analyzed EEG used in topographic pharmaco-EEG studies are still being discussed. Drug-induced changes of target variables obtained in the alpha frequency band--four absolute and four relative powers as well as three frequency measures--were utilized to assess the effects of xantinolnicotinate in demented patients using a parallel group design and the effects of buspirone in a double-blind, placebo-controlled crossover design. We conclude that for the proper evaluation of the different drug effects on the alpha activity, all these target variables should be considered. Descriptive p values of multiple comparisons within the framework of descriptive data analyses are important tools in interpreting drug effects.

Adolescent↗

PubMed1993

Clinical-pharmacological study with the two isomers (d-, l-) of fenfluramine and its comparison with chlorpromazine and d-amphetamine: blood levels, EEG mapping and safety evaluation.

In a double-blind, placebo-controlled, crossover study, the blood levels and pharmacodynamic properties of single oral doses of 15 and 30 mg d-fenfluramine (d-FEN) and 30 mg l-fenfluramine (l-FEN) were investigated as compared with 50 mg chlorpromazine (CPZ) and 20 mg d-amphetamine (AMPH) utilizing pharmaco-electroencephalogram (EEG) mapping as well as prolactin and safety assessments. Eighteen healthy young volunteers randomly (Latin square) received at weekly intervals the different treatments. Blood sampling to determine AMPH, FEN and its main metabolite norFEN, as well as plasma prolactic levels, EEG recordings and evaluation of hemodynamics and spontaneous side effects were carried out at 0, 2, 4, 6 and 8 h after drug administration. Before and 24 h after drug intake morning subjective sleep quality was also assessed. Blood level investigations after d-FEN demonstrated dose-dependent blood concentrations peaking after 2-4 h and slowly declining thereafter. NorFEN, the main metabolite, exhibited a steady increase in plasma concentrations up to the 8th h. After l-FEN a similar time course was obtained but the concentrations of the parent compound were higher and those of the metabolite lower in comparison with the d-isomer, suggesting stereoselective kinetics. d-FEN induced significant and dose-dependent pharmaco-EEG changes characterized by a decrease in total power and combined delta/theta activity and by an increase in beta activity and an acceleration of the centroid of the total activity with no changes in alpha power, which were quite different from those of the reference drugs. l-FEN produced only minimal changes (of the same type as d-FEN). 50 mg CPZ and 20 mg d-AMPH produced significant changes as compared to placebo but with quite opposite patterns, the former exhibiting the typical sedative-neuroleptic profile and the latter that typical of psychostimulants. Dose/treatment- and time-efficacy calculations based on all variables showed in the V-EEG that only 30 mg d-FEN and 50 mg CPZ were different from placebo (with peak effects in the 8th and 4th h, respectively), while in the resting condition (R-EEG) all drugs/dosages but 30 mg l-FEN differed from placebo (with the peak effect occurring in the 4th-6th h after d-FEN and l-FEN, in the 2nd h after CPZ and in the 4th-6th h after AMPH). Plasma prolactin levels were only modified by CPZ (maximal increase in the 2nd h).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗