Dose-response studies with co-dergocrine mesylate under hypoxia utilizing EEG mapping and psychometry

In a double-blind, placebo-controlled trial, human brain function and mental performance were studied under two different degrees of hypoxia after administration of two different doses (6 mg and 9 mg) of co-dergocrine mesylate (CDM) utilizing blood gas analysis, EEG mapping and psychometry. Hypoxic hypoxidosis (i.e. impairment of cerebral metabolism due to hypoxia) was experimentally induced by a fixed gas combination of 9.8% oxygen (O2) and 90.2% nitrogen (N2) (found in 6000 m altitude), and of 8.6% O2, 91.4% N2 (found in 7000 m altitude), which was inhaled for 23 min under normobaric conditions by 18 healthy volunteers. They received randomized after an adaptation session placebo, 6 mg and 9 mg co-dergocrine mesylate (CDM). Evaluation of blood gases, brain mapping and psychometry was carried out at 0, 2, 4, 6, 8 h after oral drug administration. Blood gas analysis demonstrated a drop in PO2 to 42 and 32 mm Hg 23 min after inhalation of the 9.8% and 8.6% gas mixture, respectively, PCO2 decreased to 32 and 31 mm Hg, pH increased to 7.46 and 7.47 and base excess increased to 0.50 and 0.90 nmol/l, respectively. EEG mapping demonstrated an increase in delta and decrease of alpha power and a slowing of the centroid over almost the whole brain. 6 mg and slightly less so 9 mg CDM attenuated this deterioration of vigilance (i.e. dynamic state of the neuronal network determining adaptive behavior). At the behavioral level, moderate hypoxia induced a deterioration of noopsychic performance, which was mitigated by 6 mg, but not by 9 mg CDM. A deepening of the hypoxia resulted in a loss of these brain protective effects of both doses. Decrement of the thymopsyche increased after both doses in the moderate hypoxic condition, while under marked hypoxia 6 mg CDM attenuated and 9 mg aggravated this deterioration. Time-wise, brain protective effects reached the level of statistical difference between the 2nd and the 6th hour. Somatic complaints like feeling dazed, giddiness and headache were mitigated dose dependently by CDM in the moderate, but not in the marked hypoxic hypoxidosis.

Sleep laboratory studies on the single-dose effects of serotonin reuptake inhibitors paroxetine and fluoxetine on human sleep and awakening qualities

Paroxetine is a novel antidepressant drug with selective serotonin (5-HT) reuptake inhibitory properties. In a double-blind placebo-controlled crossover sleep laboratory study the single-dose effects on objective and subjective sleep and awakening qualities were investigated after paroxetine 20, 30 and 40 mg morning doses (PX 20, 30, 40), paroxetine 30 mg evening dose, fluoxetine 40 mg morning dose (FX 40) and placebo in 18 healthy young volunteers. The drugs were orally administered in 2-wk intervals. In addition to each drug night, the adaptation night and washout night were recorded. Polysomnographic investigations (10:30 p.m. to 6:00 a.m.) showed a delayed sleep onset only after the morning intake of paroxetine, PX 40 being statistically different from placebo. Total sleep time and sleep efficiency deteriorated under morning PX 30, PX 40 and evening PX 30 as compared to placebo. The nocturnal wake time and sleep stage 1 increased under the paroxetine. Rapid eye movement (REM) reduction (min and %) occurred dose dependently after all paroxetine doses, but the REM latency was lengthened only after the morning intake. The suppressant effect on REM sleep is characteristic for antidepressants and was still significant in the washout nights following PX 40 and evening PX 30. The only statistically relevant finding under 40 mg fluoxetine referred to the increase of REM latency in both drug and washout nights. In contrast to objective results, subjective sleep quality remained generally unchanged. Attention, concentration and reaction performance improved under paroxetine as compared to baseline. The deterioration of well-being under PX 40 might be related to the appearance of drowsiness and nausea. Blood pressure and pulse rate were unaffected.

[Relation between blood levels and average quantitative EEG and psychometrically assessed pharmacodynamic changes following zotepine]

In a double-blind, placebo-controlled study, the relationships between blood levels and pharmacodynamics of zotepine were investigated in 15 healthy subjects. They received randomized at weekly intervals single oral doses of 25, 50 and 100 mg zotepine and 50 mg clozapin as reference substance. Blood sampling for zotepine and prolactin plasma levels, quantitative EEG analyses, psychometry and tolerability measures were carried out at the hours 0, 1, 2, 4, 6 and 8. There was a dose-dependent increase in zotepine plasma levels with a tmax between 2-4 hours post-drug and cmax: 6.9, 14.8 and 19.6 ng/ml for the 3 doses, respectively and a slow decline thereafter. Prolactin levels also rose dose dependently, peaking in the 4th hour. Regression and correlation analyses demonstrated: the higher the zotepine plasma levels, the more delta/theta, the less alpha activity and the slower the centroid in the spectral analysed EEG and the more decrease in reaction time performance, numerical memory and CFF in psychometry. Neurophysiological changes started at 8 ng/ml, psychometric ones at 9 ng/ml. Our pharmacodynamic findings suggested zotepine to be a sedative broad-band neuroleptic, which was also reflected in the side effects.

EEG brain mapping in diagnostic and therapeutic assessment of dementia

EEG brain mapping has been proven to be a valuable method in diagnostic and therapeutic assessment in dementia trials, because it is a readily available, inexpensive, high time-resolution method for objective and quantitative evaluation of the neurophysiological aspects of dementias. In 111 mildly to moderately demented patients diagnosed according to DSM-III as both degenerative [senile dementia of the Alzheimer type (SDAT)] and vascular [multi-infarct dementia (MID) type], we were interested in showing not only differences between SDAT and MID patients and normal controls but also the relationship between CT scans, EEG maps, clinical ratings and psychometric tests. CT measures included 10 cerebrospinal fluid (CSF) space variables as well as 17 cortical density measures (1.7 mm3 cubes, Hounsfield units). Clinical investigations consisted of the SCAG score/factors, the digit symbol substitution test, the trailmaking test and the digit span forward test. In brain maps, SDAT patients showed slightly to moderately more slow and less alpha and beta activity as well as a slowing of the dominant frequency (DF) and the centroid (C) than did normal controls. These findings were most prominent in parietal and temporal regions. MID patients exhibited markedly augmented delta/theta and attenuated alpha and beta activity and a slowing of the DF and C. These neurophysiological findings suggest a deterioration of vigilance. Differences between SDAT and MID patients were found mostly in measures concerning differences in the maps. Brain maps of correlation coefficients between CT and EEG variables demonstrated: the greater the anterior horn distance, lateral ventricle distance, and Evan's index, as well as the less cortical density, the more delta/theta and the less alpha and beta activity in the EEG. Moreover, the higher the delta/theta, the less alpha and beta activity, the higher the SCAG scores, and the worse the psychometric performance. From the pharmacological point of view, we observed a significant improvement in vigilance after administration of several nootropic drugs both in normal and pathologically aging subjects, which was associated also with improvement of psychopathometric scores. Based on multi-variante analysis of variance (MANOVA)/Hotlelling T2 we observed a drug's effect in different brain regions of MID and SDAT patients. Thus, pharmaco-EEG mapping mediates valuable information regarding if, how, when, in which dosage, and where a nootropic drug acts on its target organ--the aging human brain.

Brain protection of nicergoline against hypoxia: EEG brain mapping and psychometry

In a double-blind, placebo-controlled trial human brain function and mental performance as well as the antihypoxidotic properties of nicergoline were studied utilizing blood gas analysis, EEG brain mapping and psychometry. Hypoxic hypoxidosis was experimentally induced by a fixed gas combination of 9.8% oxygen (O2) and 90.2% nitrogen (N2) equivalent to 6,000 m altitude, which was inhaled for 23 min under normobaric conditions by 16 healthy volunteers. They received randomized after an adaptation session placebo, 10 mg, 30 mg and 60 mg nicergoline (NIC). Evaluation of blood gases, brain mapping and psychometry was carried out at 0, 2, 4, 6, 8 hrs oral drug administration. Blood gas analysis demonstrated a drop in PO2 from 95 to 35 and 34 mm Hg in the 14 and 23 min of inhalation, respectively. PCO2 decreased too (38 to 34 and 34 mm Hg), while pH increased (7.39 to 7.44 and 7.44). Base excess increased (-0.6 to 0.6 and 0.4) while standard bicarbonate decreased (24.4 to 24.1 and 23.8 mmol/l). Thus, blood gases remained stable between the 14 and 23 min of hypoxia during which time the neurophysiological and behavioral evaluations were carried out. EEG brain mapping exhibited an increase in delta/theta activity mostly over the parietal, temporal and central regions (left more than right), while alpha activity decreased (mostly over the parietal, central, frontal, fronto-temporal and temporo-occipital regions). 30 and 60 mg NIC attenuated this deterioration of vigilance. At the behavioral level, hypoxic hypoxidosis induced a deterioration of the noo- and thymospsyche which was mitigated by NIC. Based on 13 psychometric variables, the hypoxia-induced performance decrement was on the overall (2nd-8th hr) 43% after placebo as compared with pretreatment normoxic values, while only 29, 24 and 31% after 10, 30 and 60 mg nicergoline, respectively. The difference between placebo and the optimal dosage of nicergoline 30 mg reached the level of statistical significance (p less than 0.01, multiple Wilcoxon).

Sleep laboratory studies on single dose effects of suriclone

1. In a double-blind, placebo-controlled sleep laboratory study single doses of suriclone, a new non-benzodiazepine anxiolytic binding to benzodiazepine receptors, were investigated with respect to sleep and awakening. 2. Sixteen healthy young volunteers spent 10 nights in the sleep laboratory: 1 adaptation night, 1 baseline night and 4 drug nights (placebo; 0.2 mg, 0.4 mg suriclone; 2 mg lorazepam as reference drug) and 4 subsequent wash-out nights (drug-interval: 1 week). Somnopolygraphic investigations (22.30 h to 06.00 h) were commenced 0.5 h after drug-intake. A self-rating scale for sleep and awakening quality as well as psychometric tests were completed in the morning. 3. Hypnotic effects were most pronounced after lorazepam in regard to total sleep time and sleep efficiency. After lorazepam as well as after 0.4 mg suriclone nocturnal awakenings decreased significantly as compared with placebo, which was reflected in an improved subjective sleep quality after both dosages. Suriclone 0.2 mg did not induce any alterations in all night sleep. 4. In the morning, well-being, drowsiness and reaction time performance deteriorated after lorazepam as compared with placebo but not after suriclone. The latter was significantly superior to lorazepam with respect to subjective awakening quality, well-being, emotional rapport, drowsiness and attention. 5. Blood pressure and pulse remained unchanged after all of the drugs. Critical flicker frequency and muscle strength decreased only after lorazepam as compared with placebo.

Topographic brain mapping of EEG after acute application of ergotalkaloids in the elderly

In a double-blind, placebo-controlled, crossover study the encephalotropic and nootropic effects of single doses of two ergotalkaloids (30 and 60 mg nicergoline and 5 mg co-dergocrine mesylate (CDM)) were investigated in 12 elderly subjects (mean age 67 years), utilizing topographic brain mapping of the EEG. Evaluation of EEG, memory, pulse and blood pressure were carried out at 0, 2, 4, 6 and 8 h. Topographic brain maps demonstrated an augmentation of total power, an acceleration of the centroid of the total activity, a decrease of delta/theta and an increase of beta activity (mostly in the alpha-adjacent frequency bands), as well as an acceleration of the centroid of the delta/theta and a slowing of the beta centroid. These changes are indicative of improvement in vigilance of elderly subjects after ergotalkaloids, which was also reflected in the significant improvement of memory after nicergoline. Topographically, the main effect was found over the frontal, central and temporal regions. Timewise, the pharmacodynamic peak fell into the 4th h, although with 60 mg significant encephalotropic effects could be observed in the 2nd and in the 6th h. The drugs were well tolerated.

Topographic mapping of cognitive event-related potentials in a double-blind, placebo-controlled study with the hemoderivative Actovegin in age-associated memory impairment

In a double-blind placebo-controlled study, the effects of Actovegin on cognitive event-related potentials were studied in 18 age-associated memory impairment (AAMI) patients. Actovegin is a protein-free metabolically active hemoderivative improving oxygen and glucose utilization. Each patient was treated, in randomized order, for 2 weeks with 250 ml 20% Actovegin and 250 ml placebo daily with an interval of 3 weeks in between. Psychophysiological tests were carried out by means of the Viennese Psychophysiological Test System (VPTS) before as well as 5 h after the administration of one single infusion on day 1 (acute effect), before (subacute effect) as well as after one additional superimposed infusion on day 15 (superimposed effect). There was no effect on earlier stages of information processing measured by N1 and P2 component of nontarget ERP nor on ERP latencies. However, P300 amplitude increased after acute, subacute as well as superimposed infusion of Actovegin as compared to placebo, confirming the hypothesis that nootropic drugs may influence the P300 amplitude in the sense of an improved availability of cognitive processing resources. This increase of P300 amplitude (up to 4.8 microV), seen specifically in central and parietal regions, proved to be significant in a confirmatory test.

Smooth pursuit eye movements in schizophrenia: influences of neuroleptic treatment and the question of specificity

The authors investigated smooth pursuit eye movements (SPEMs) in 66 schizophrenic and 40 major affective patients and 39 healthy controls. The results showed significant differences of both patient groups as compared to the controls. Schizophrenics with neuroleptic treatment in the preceding 2 years were significantly more disturbed than the controls, the affective patients and the untreated schizophrenics. Acute neuroleptic medication and neuroleptic treatment of a duration of 4-6 weeks appear not to significantly influence the quality of SPEMs.

EEG brain mapping and psychometry in age-associated memory impairment after acute and 2-week infusions with the hemoderivative Actovegin: double-blind, placebo-controlled trials

In a double-blind, placebo-controlled study the encephalotropic and psychotropic effects of Actovegin--a protein-free metabolically active hemoderivative improving oxygen and glucose utilization--were investigated in age-associated memory impairment (AAMI) patients, utilizing EEG brain mapping, psychometric and psychophysiological analyses. Each patient had a treatment of 2 weeks with 250 ml 20% Actovegin and 250 ml placebo daily with an interval of 3 weeks in between (the order of drugs sequence was randomized). Pharmacodynamic evaluations were carried out 0, 2, 4, 6 and 8 h after the administration of one single infusion on day 1 (acute effect), at 0 h on day 15 (subacute effect) as well as 2, 4, 6 and 8 h after one additional superimposed infusion on day 15 (superimposed effect). EEG brain mapping demonstrated that Actovegin exerted a significant action on the human brain function as compared with placebo characterized by a decrease of delta and theta, an increase of alpha-adjacent slow beta, a decrease of fast beta, an acceleration of the centroid of the delta/theta and alpha activity, a slowing of the beta centroid and an increase of the centroid of the total activity. Topographically the encephalotropic effects were mostly pronounced in the parietal, frontocentral and temporooccipital regions. These changes are indicative of an improvement of vigilance which was proven also by psychometric investigations at the behavioral level. Actovegin improved the noopsyche mostly in regard to attention, memory and rigidity/perseveration measures. In regard to the thymopsyche an improvement was noted in mood, affectivity, well-being and sedation. Psychophysiological evaluations demonstrated an increase in CFF, skin conductance, pupillary diameter and shortening of the latency and augmentation of the amplitude of the pupillary response. Time-efficacy calculations exhibited more effect after subacute than acute administration with the pharmacodynamic maximum in the 4th h after the superimposed dose. Evaluations of pulse, blood pressure and side effects demonstrated a very good tolerability of the drug. Our present neurophysiological, psychometric and psychophysiological findings confirm earlier results obtained in elderlies with similar methodology.

Differential effects of the new central adrenergic agonist modafinil and d-amphetamine on sleep and early morning behaviour in elderlies

Modafinil (CRL 40476) is a new central alpha-adrenergic agonist with vigilance-promoting properties. In a double-blind, placebo-controlled sleep laboratory study its single-dose effects on sleep and early morning behaviour were investigated and compared with d-amphetamine. Ten elderly healthy volunteers (mean age: 68 years) spent 12 nights in the sleep laboratory: one adaptation night, one baseline night, five drug nights (100 mg and 200 mg modafinil; 10 mg and 20 mg d-amphetamine; placebo) and five subsequent washout nights. The drugs were administered orally in one week intervals at 10:00 p.m., and all-night somnopolygraphic investigations were performed between 10:30 p.m. and 6:00 a.m. A self-rating scale for sleep and awakening quality as well as psychometric tests were completed in the morning. d-amphetamine caused a dose-dependent impairment of sleep maintenance and sleep architecture, while modafinil did not. Thus, a significant reduction of total sleep time, REM-sleep and sleep stage 2 was seen after d-amphetamine when compared to placebo and 100 mg modafinil. Corresponding with these objective results, subjective sleep quality deteriorated significantly only after 20 mg d-amphetamine as compared to placebo. Morning investigations revealed an increase of CFF after 20 mg d-amphetamine. Pulse rate, evening and morning blood pressure remained unchanged. These findings suggest a different mode of action of the two compounds.

Psychophysiological research in psychiatry and neuropsychopharmacology. II. The investigation of antihypoxidotic/nootropic drugs (tenilsetam and co-dergocrine-mesylate) in elderlies with the Viennese Psychophysiological Test-System (VPTS)

In a double-blind placebo-controlled study, the effects of tenilsetam, a novel antihypoxidotic/nootropic agent, on spontaneous and event-related activity of the central and autonomous nervous system were studied in 15 elderly subjects of both sexes aged 58-77 years by means of the Viennese Psychophysiological Test-System (VPTS). The VPTS includes a special selection and combination of experimental situations, physiological measurements, behavioral measurements and data analysis. At weekly intervals, the subjects received randomized single oral doses of placebo, 150 mg, 300 mg and 900 mg tenilsetam (TEN) and 5 mg co-dergocrine-mesylate (CDM) as reference drug. Psychophysiological testings were carried out before and 2 h after drug administration. Evaluation of the spontaneous EEG-activity demonstrated no significant drug effects as compared to placebo. In contrast, TEN showed a dose-dependent augmentation of the N1-P2 and N2-P300 amplitudes of the event-related potentials (ERPs) in specific experimental conditions. In reference to placebo, the increase of N2-P300 amplitude after the highest dosage of TEN, as well as after CDM, amounted to approximately 5 microV, which confirms the hypothesis that nootropic drugs may influence the P300 amplitude in the sense of an improved availability of cognitive processing resources. There was no effect on ERP latencies, on mean amplitudes of contingent negative variation and of post-imperative negative variation, on autonomous nervous system, on psychological measurements, nor on reaction time. However, specific improvements were observed in psychomotor measures, such as synchronization accuracy and rhythmicity. These findings highlight the importance of using EEG and ERP measures in different experimental situations in conjunction with behavioral, psychological and autonomous nervous system measures to study nootropic drug effects.

Psychophysiological research in psychiatry and neuropsychopharmacology. I. Methodological aspects of the Viennese Psychophysiological Test-System (VPTS)

In order to find a psychophysiological paradigm for clinical application we have developed the Viennese Psychophysiological Test-System (VPTS), which includes a special selection and combination of experimental situations, physiological measurements, behavioral measurements and data analysis. This study presents detailed information concerning these four aspects. Experimental situations are related to the human model of information processing, where short changes of stimulus-reaction-correlated processes are selected: resting conditions (eyes open, eyes closed), habituation-orienting test, psychomotor-performance test, signal-detection test and reaction-time test. Physiological measures include central and peripheral activity of the cerebrospinal and autonomic nervous system: cortical activity (spontaneous electroencephalogram, auditory evoked potentials, late positive components, slow potentials), ocular activity (eye and eyelid movements), electrodermal activity (skin conductance), cardiac activity (heart rate measurement), respiratory activity (rate of respiration) and peripheral vascular activity (finger pulse volume). Behavioral measurements extend from micro behavior to complex diagnostic systems: psychomotor measurements, self-reported mood, arousal and visceral perception, psychological and psychiatric interviews. The application of this test system in 15 elderly subjects of both sexes aged 58-77 years gives information which exceeds the sum of the singular constructing elements of the VPTS.

Comparative bioavailability studies with a new mixed-micelles solution of diazepam utilizing radioreceptor assay, psychometry and EEG brain mapping

In a double-blind, placebo-controlled study the pharmacokinetic and pharmacodynamic properties of a standard solution of diazepam (DZ) (ValiumR) were compared with those of a novel diazepam mixed-micelles solution (DZ MM) (Valium MMR) both after i.v. and i.m. application utilizing radioreceptor assay, quantitative pharmaco-EEG and brain mapping techniques as well as psychometric and psychophysiological methods. The local tolerance was studied as well. The subjects received randomized and, in weekly intervals, following injections: (1) 10 mg DZ i.v. + placebo i.m.; (2) 10 mg DZ MM i.v. + placebo i.m.; (3) placebo i.v. + 10 mg DZ i.m.; (4) placebo i.v. + 10 mg DZ MM i.m.; (5) placebo i.v. + placebo i.m. Blood sampling, EEG-recordings, psychometric and psychophysiological tests as well as tolerance evaluations were carried out at 0, 1/2, 1, 2, 4, 6 and 8 h. Blood level evaluation demonstrated after i.m. application a significantly shortened tmax, a higher Cmax and generally higher plasma concentrations in the first and second hour following the mixed-micelles solution than the standard formulation, which suggests better absorption of the former than the latter in the muscle. Subsequent to i.v. administration, lower blood levels were observed between 30 min and 2 h after DZ MM than DZ. Power spectral density analysis of the EEG resulted in typical anxiolytic-sedative pharmaco-EEG profiles after all 4 active substances as compared with placebo. However, there were significant inter-drug differences as far as topographic aspects (pharmaco-EEG maps) were concerned. DZ MM i.v. induced significantly more initial but also late delta augmentation, alpha attenuation and centroid slowing than DZ i.v. which suggests more sedative effects at those times. Following i.m. application, a significantly more pronounced delta/theta attenuation, beta augmentation and centroid acceleration after DZ MM than DZ suggested more anxiolytic effects of the novel than the standard formulation. Discriminant analysis of changes in 6 thymopsychic, 12 noopsychic and 17 psychophysiological variables demonstrated the best discrimination of the 4 substances based on thymopsychic effects. Considering the latter, all 4 active compounds differed significantly from placebo, with no inter-drug differences after i.v. application but a marked superiority of the novel mixed-micelles solution over the standard solution after i.m. application. Specifically, DZ MM i.m. induced more desactivation and affect-attenuation than DZ i.m.(ABSTRACT TRUNCATED AT 400 WORDS)

Double-blind, placebo-controlled quantitative EEG and psychometric studies in elderlies on vigilance-promoting effects of an almitrine/raubasine combination (Duxil)

In a double-blind, placebo-controlled study the encephalotropic and psychotropic properties of an acutely and 3-weeks subacutely administered novel drug Duxil (consisting of 30 mg of the antihypoxic almitrine which increases the oxygenation of the arterial blood by specific action on the pulmonary exchange system and of 10 mg raubasine, which potentiates this effect via increase in peripheral circulation), were investigated in 12 elderly subjects in their 70s. Each subject had a treatment of 3 weeks with Duxil and placebo (1 tablet b.i.d.) with an interval of 1 week in between (the order of drug sequence was randomized). EEG recordings, psychometric and psychophysiological tests as well as evaluation of pulse, blood pressure and side effects were carried out at 0, 2, 4, 6 and 8 h after the administration of one single dose on day 1 (acute effect), at the 0 h on day 21 (subacute effect) as well as at the 2, 4, 6, and 8 h after one additional superimposed dosage on day 21 (superimposed effect). Computer-assisted spectral analysis of the EEG demonstrated after single doses of two tablets of Duxil only subtle changes in the resting EEG, while after subacute administration and even more so after one superimposed dosage highly significant changes were observed, which were characterized by an increase of total power, alpha and alpha-adjacent beta activity, decrease in fast beta activity, and by an augmentation of absolute and relative power of the dominant frequency. These findings are indicative of an improvement in vigilance. The latter was seen also at the behavioral level, as psychometric tests showed specifically in noopsychic variables a significant improvement in intellectual, mnestic and psychomotor performance after the novel antihypoxic compound, as compared with placebo. There were practically no changes in thymopsychic variables. Evaluation of psychophysiological variables and side effects showed extremely good tolerability of the drug.

Topographic brain mapping of EEG before and after open-heart surgery

The brain function of 60 patients undergoing open-heart surgery (36 patients receiving coronary artery bypass, 21 patients valve replacements, 3 both) was investigated before and 10 days after the operation utilizing topographic brain mapping of the electroencephalogram (EEG). The postoperative EEG changes were characterized by a slight delta-theta increase, an alpha decrease [especially in the fast alpha (10.5-13 Hz) band] and a beta increase in the relative power. The total power and the absolute power of the delta-theta, alpha and beta showed a decrease, the dominant frequency a significant slowing from 9.7 to 9.3 Hz. The centroid of alpha and beta activity decreased as well. These results are similar to findings obtained in patients with organic brain syndrome. The EEG changes were prominent over the left hemisphere, which may be of particular clinical relevance.

Contralateral eye movements and alpha reactivity of lithium patients in recognition tasks

For the purpose of analyzing memory deficits in patients on lithium therapy the Psychological Labor (E. Opgenoorth et al.) and Lithium Department (R. Wolf et al.) studied not only psychological performance but also biosignals of elementary complexity (characteristic values of eye movements as a reaction to simple light stimuli) and of higher complexity, i.e. those which accompany the cognitive processing of information. Recall and recognition performance for incidentally learned word and picture items was tested in 14 patients receiving lithium treatment. Simultaneously registered EEG (O1-Cz and O2-Cz) and lateral eye movements (LEM) were analyzed with reference to different stimuli. Absolute alpha power and relative event-related desynchronization (ERD) show differences in EEG reactivity between healthy individuals and lithium patients demonstrated by differences in the amplitudes. LEM are characterized by a slight delay of the peaks.

Topographic brain mapping of EEG in neuropsychopharmacology--Part I. Methodological aspects

Topographic brain mapping of the electroencephalogram (EEG) is a promising new method in neuropsychiatry and neuropsychopharmacology. Rapid advances in computer technology allow on-line analysis by means of micro-computers. This paper describes an acquisition and signal analysis system for studying neurophysiological and neuropsychopharmacological aspects of human brain function. It consists of a server micro-computer functioning as an acquisition unit which is connected to a workstation micro-computer for statistical analysis and subsequent documentation of data on a printer and color plotter. According to the recommendations for standardization of data acquisition and signal analysis in pharmaco-electroencephalography, the paper mediates detailed information concerning recording and analysis equipment with special emphasis on the treatment of artifacts. Since up to now there is no normative consensus on the choice of reference conventions and interpolation algorithms, the system is designed for high flexibility to enable empirical comparisons between different methods.

Topographic brain mapping of EEG in neuropsychopharmacology--Part II. Clinical applications (pharmaco EEG imaging)

Multi-lead analysis of drug-induced changes in human brain function as monitored by the scalp-recorded electroencephalogram (EEG) and subsequent imaging of topographic pharmaco-EEG maps has become possible and practical with the advent of modern mini- and micro-computers. The present paper gives a survey about topographic analyses of pharmaco-EEG data obtained in systematic double-blind, placebo-controlled studies in normal healthy volunteers involving representative drugs of 5 different psychopharmacological classes, such as neuroleptics (chlorprothixene), antidepressants (imipramine), tranquilizers (diazepam), psychostimulants (caffeine), and antihypoxidotics/nootropics (pyritinol). The determination of cerebral bioavailability utilizing time- and dose-efficacy relations, as well as the evaluation of bioequipotency of different formulations of compounds is shown. Topographic pharmaco-EEG seems not only to confirm our previous knowledge that quantitative analysis of the human EEG in combination with certain statistical procedures ("quantitative pharmaco-EEG") is a valuable method to determine if, how, when and at which dosage a drug will be centrally effective, but also to have the potential to show effects of psychotropic drugs on the target organ--the human brain--which could not be previously picked up by single lead recordings. Topographic pharmaco-EEG imaging can be viewed as an enlargement of our armamentarium to better understand the mode of action of psychotropic drugs in human neuropsychopharmacology, as well as to monitor and (eventually) predict therapeutic efficacy in patients.

Comparative placebo-controlled pharmacodynamic studies with zotepine and clozapine utilizing pharmaco-EEG and psychometry

In a double-blind, placebo-controlled study the encephalotropic and psychotropic properties of zotepine - a new tricyclic dibenzothiepine with antidopaminergic, adrenolytic and antiserotoninergic properties - were investigated utilizing quantitative EEG, psychometric and psychophysiological tests as well as clinical observations. Fifteen normal volunteers received randomized (latin square design) and at weekly intervals single oral doses of placebo, 25 mg, 50 mg and 100 mg zotepine as well as 50 mg clozapine as reference compound. Plasma samplings for blood levels, EEG recordings, and evaluation of blood pressure, pulse rate and side-effects were carried out at the hours 0, 1, 2, 4, 6 and 8, while psychometric data were recorded at the same time except the first hour. Computer-assisted spectral analysis of the EEG demonstrated after all three doses significant changes as compared with placebo characterized by an augmentation of delta and theta activity, decreased of alpha and beta activity, slowing of the centroid of the total activity and alpha activity, and decrease of the dominant frequency and its absolute and relative power. Such changes are typical for low-potency basic neuroleptics of the sedative type such as chlorpromazine. Clozapine also augmented slow activities, decreased alpha activity, the dominant frequency and the alpha centroid, but induced in contrast to zotepine a concomitant increase of fast beta activity, acceleration of the beta centroid and no slowing of the dominant frequency, while the total power was significantly attenuated. These findings confirm earlier reports about the pharmaco-EEG profile of clozapine, which has a resemblance to profiles of anticholinergic antidepressants of the amitriptyline type. Psychometric tests demonstrated after the higher doses of zotepine and clozapine a deterioration of noopsychic and thymospsychic functions which was more pronounced after the reference compound than after zotepine. The lowest dose of zotepine, 25 mg, even produced an improvement in numerical memory and complex reaction. CFF, skin conductance, pupillary diameter and pupillary response measurements decreased after both compounds. Dose-efficacy calculations showed 100 mg zotepine and clozapine to be the most CNS-effective compounds, followed by 50 mg and 25 mg zotepine, while placebo induced the least changes. Time-efficacy calculations showed neurophysiological and behavioral peak effects after zotepine at the 4th and 6th hour, as compared with the 2nd and 4th hour after clozapine. Pulse rate increased with both compounds; blood pressure decreased after clozapine but remained unchanged after zotepine.(ABSTRACT TRUNCATED AT 400 WORDS)