Biomedical subjects

Peter Anderer

Publications and source records attributed to Peter Anderer.

At least 19 recordsLinked to original sources

PubMed2006

Low-resolution brain electromagnetic tomography (LORETA) identifies brain regions linked to psychometric performance under modafinil in narcolepsy.

Low-resolution brain electromagnetic tomography (LORETA) showed a functional deterioration of the fronto-temporo-parietal network of the right hemispheric vigilance system in narcolepsy and a therapeutic effect of modafinil. The aim of this study was to determine the effects of modafinil on cognitive and thymopsychic variables in patients with narcolepsy and investigate whether neurophysiological vigilance changes correlate with cognitive and subjective vigilance alterations at the behavioral level. In a double-blind, placebo-controlled crossover design, EEG-LORETA and psychometric data were obtained during midmorning hours in 15 narcoleptics before and after 3 weeks of placebo or 400 mg modafinil. Cognitive investigations included the Pauli Test and complex reaction time. Thymopsychic/psychophysiological evaluation comprised drive, mood, affectivity, wakefulness, depression, anxiety, the Symptom Checklist 90 and critical flicker frequency. The Multiple Sleep Latency Test (MSLT) and the Epworth Sleepiness Scale (ESS) were performed too. Cognitive performance (Pauli Test) was significantly better after modafinil than after placebo. Concerning reaction time and thymopsychic variables, no significant differences were observed. Correlation analyses revealed that a decrease in prefrontal delta, theta and alpha-1 power correlated with an improvement in cognitive performance. Moreover, drowsiness was positively correlated with theta power in parietal and medial prefrontal regions and beta-1 and beta-2 power in occipital regions. A less significant correlation was observed between midmorning EEG LORETA and the MSLT; between EEG LORETA and the ESS, the correlation was even weaker. In conclusion, modafinil did not influence thymopsychic variables in narcolepsy, but it significantly improved cognitive performance, which may be related to medial prefrontal activity processes identified by LORETA.

Adult↗

PubMed2006

EEG topography and tomography (LORETA) in the classification and evaluation of the pharmacodynamics of psychotropic drugs.

By multi-lead computer-assisted quantitative analyses of human scalp-recorded electroencephalogram (QEEG) in combination with certain statistical procedures (quantitative pharmaco-EEG) and mapping techniques (pharmaco-EEG mapping or topography), it is possible to classify psychotropic substances and objectively evaluate their bioavailability at the target organ, the human brain. Specifically, one may determine at an early stage of drug development whether a drug is effective on the central nervous system (CNS) compared with placebo, what its clinical efficacy will be like, at which dosage it acts, when it acts and the equipotent dosages of different galenic formulations. Pharmaco-EEG maps of neuroleptics, antidepressants, tranquilizers, hypnotics, psychostimulants and nootropics/cognition-enhancing drugs will be described. Methodological problems, as well as the relationships between acute and chronic drug effects, alterations in normal subjects and patients, CNS effects and therapeutic efficacy will be discussed. Imaging of drug effects on the regional brain electrical activity of healthy subjects by means of EEG tomography such as low-resolution electromagnetic tomography (LORETA) has been used for identifying brain areas predominantly involved in psychopharmacological action. This will be shown for the representative drugs of the four main psychopharmacological classes, such as 3 mg haloperidol for neuroleptics, 20 mg citalopram for antidepressants, 2 mg lorazepam for tranquilizers and 20 mg methylphenidate for psychostimulants. LORETA demonstrates that these psychopharmacological classes affect brain structures differently. By considering these differences between psychotropic drugs and placebo in normal subjects, as well as between mental disorder patients and normal controls, it may be possible to choose the optimum drug for a specific patient according to a key-lock principle, since the drug should normalize the deviant brain function. Thus, pharmaco-EEG topography and tomography are valuable methods in human neuropsychopharmacology, clinical psychiatry and neurology.

Brain↗

PubMed2005

Age-related cognitive decline in the menopause: effects of hormone replacement therapy on cognitive event-related potentials.

OBJECTIVE: Although epidemiological and clinical studies suggest that hormone replacement therapy (HRT) may protect against cognitive disorders and neurodegenerative diseases, the relation between estrogen and cognition in postmenopausal women remains controversial. METHODS: In a double-blind placebo-controlled, parallel group design study the effects of HRT with the estrogen-progestogen combination Presomen 1.25 compositum((R)) (1.25mg equine conjugated estrogens administered for 21 days plus the progestogen 5mg medrogeston given for 11 days) on event-related potentials (ERPs) in postmenopausal patients with age-related cognitive decline (DSM-IV code 780.9, ICD-10 code R 41.8) were investigated. After a pre-drug comparison with age-matched normal postmenopausal controls, 48 psychotropic drug-free patients aged 60 +/- 6 years were randomized to receive either placebo or verum for 4 months. ERPs were recorded before as well as on the 91-92 days of the study, which thus fell into the estrogen phase of the treatment during the fourth cycle. RESULTS: At baseline, patients showed a lengthening of P300 latency and an attenuation of P300 amplitudes as compared with normal controls. After HRT with Presomen, a significant shortening of P300 latency as compared with placebo was observed. CONCLUSIONS: The baseline P300 differences suggest that in the patient group the aging process was advanced, while after HRT with Presomen a significant improvement and normalization of information processing as indexed by P300 was observed.

Cognition↗

PubMed2005

On the pharmacotherapy of sleep bruxism: placebo-controlled polysomnographic and psychometric studies with clonazepam.

OBJECTIVES: Sleep bruxism (SB) is a parasomnia defined as a stereotyped movement disorder characterized by grinding or clenching of the teeth during sleep. Pathophysiologically, SB is the result of biological and psychosocial influences. Treatment comprises behavioral, orthodontic and pharmacological interventions. While benzodiazepines and muscle relaxants have been reported by clinicians to reduce bruxism-related motor activity, placebo-controlled studies are lacking. Thus, the aim of the present study was to investigate the acute effects of clonazepam (Rivotril) as compared with placebo, utilizing polysomnography and psychometry. METHOD: Ten drug-free outpatients (6 females, 4 males), aged 46.5 +/- 13.1 years, suffering from SB (ICD-10: F45.8; ICSD: 306.8) and having been treated by bite splints were included in the trial. Comorbidity was high: 7 patients presented nonorganic insomnia related to adjustment or anxiety disorders (5 patients) or depression (2 patients); all patients had a concomitant movement disorder (6 restless legs syndrome, 4 periodic leg movement disorder). After one adaptation night, patients received placebo and 1 mg clonazepam 1/2 hour before lights out in a single-blind, nonrandomized study design. Objective sleep quality was determined by polysomnography, subjective sleep and awakening quality by rating scales, objective awakening quality by psychometric tests. Clinical evaluation was based on the Pittsburgh Sleep Quality Index (PSQI), the Zung Depression (SDS) and Anxiety (SAS) Scales, the Quality of Life Index, the Epworth Sleepiness Scale and the International Restless Legs Syndrome Study Group (IRLSSG) Scale. RESULTS: On admission, SB patients exhibited deteriorated PSQI, SAS, SDS and IRLSSG measures. As compared with placebo, 1 mg clonazepam significantly improved the mean bruxism index from 9.3 to 6.3/h of sleep. Furthermore, it significantly improved the total sleep period, total sleep time, sleep efficiency, sleep latency and time awake during the total sleep period, and increased stage 2 sleep and movement time. Periodic leg movements decreased significantly, while the apnea index and apnea-hypopnea index increased marginally, but remained within normal limits. Subjective sleep quality improved as well, while in mood, performance and psychophysiology no changes were observed. CONCLUSION: Acute clonazepam therapy significantly improved not only the bruxism index but also objective and subjective sleep quality, with unchanged mood, performance and psychophysiological measures upon awakening, suggesting good tolerability of the drug.

Adult↗

PubMed2005

An E-health solution for automatic sleep classification according to Rechtschaffen and Kales: validation study of the Somnolyzer 24 x 7 utilizing the Siesta database.

To date, the only standard for the classification of sleep-EEG recordings that has found worldwide acceptance are the rules published in 1968 by Rechtschaffen and Kales. Even though several attempts have been made to automate the classification process, so far no method has been published that has proven its validity in a study including a sufficiently large number of controls and patients of all adult age ranges. The present paper describes the development and optimization of an automatic classification system that is based on one central EEG channel, two EOG channels and one chin EMG channel. It adheres to the decision rules for visual scoring as closely as possible and includes a structured quality control procedure by a human expert. The final system (Somnolyzer 24 x 7) consists of a raw data quality check, a feature extraction algorithm (density and intensity of sleep/wake-related patterns such as sleep spindles, delta waves, SEMs and REMs), a feature matrix plausibility check, a classifier designed as an expert system, a rule-based smoothing procedure for the start and the end of stages REM, and finally a statistical comparison to age- and sex-matched normal healthy controls (Siesta Spot Report). The expert system considers different prior probabilities of stage changes depending on the preceding sleep stage, the occurrence of a movement arousal and the position of the epoch within the NREM/REM sleep cycles. Moreover, results obtained with and without using the chin EMG signal are combined. The Siesta polysomnographic database (590 recordings in both normal healthy subjects aged 20-95 years and patients suffering from organic or nonorganic sleep disorders) was split into two halves, which were randomly assigned to a training and a validation set, respectively. The final validation revealed an overall epoch-by-epoch agreement of 80% (Cohen's kappa: 0.72) between the Somnolyzer 24 x 7 and the human expert scoring, as compared with an inter-rater reliability of 77% (Cohen's kappa: 0.68) between two human experts scoring the same dataset. Two Somnolyzer 24 x 7 analyses (including a structured quality control by two human experts) revealed an inter-rater reliability close to 1 (Cohen's kappa: 0.991), which confirmed that the variability induced by the quality control procedure, whereby approximately 1% of the epochs (in 9.5% of the recordings) are changed, can definitely be neglected. Thus, the validation study proved the high reliability and validity of the Somnolyzer 24 x 7 and demonstrated its applicability in clinical routine and sleep studies.

Adult↗

PubMed2005

Insomnia in somatoform pain disorder: sleep laboratory studies on differences to controls and acute effects of trazodone, evaluated by the Somnolyzer 24 x 7 and the Siesta database.

Patients with chronic pain often suffer from sleep disturbances, specifically decreased deep sleep, and thus may get into a vicious circle which maintains their pain condition. Utilizing polysomnography and psychometry, objective and subjective sleep and awakening quality was investigated in 11 patients with nonorganic insomnia (F51.0) related to somatoform pain disorder (SPD; F45.4) as compared with age- and sex-matched healthy controls of the Siesta normative database. Patients demonstrated a markedly deteriorated Pittsburgh Sleep Quality Index, a decreased Quality of Life Index, slightly increased self-reported anxiety (Zung SAS) and depression scores (Zung SDS), as well as an increased Epworth Sleepiness Scale and International Restless Legs Syndrome Scale score. Subjective sleep and awakening quality was markedly reduced, while somatic complaints were increased. Polysomnographic evaluation by a recently developed automatic sleep classifier (Somnolyzer 24 x 7) based on the rules of Rechtschaffen and Kales demonstrated reduced slow-wave sleep (SWS), the target variable in the present study, a decreased stage shift index, increased SWS latency and stage 4 sleep (S4) latency and an increased frequency of shifts from S2 to wakefulness (W) in patients as compared with controls. Minimal oxygen saturation was found decreased, periodic leg movements (PLMs) were increased. In the morning, patients showed deteriorated well-being, drive, mood and wakefulness. There were no significant noopsychic or psychophysiological differences between patients and controls (except for a reduced numerical memory and a slightly increased morning diastolic blood pressure in patients). Subsequent evaluation of the acute effects of 100 mg of a controlled-release formulation of trazodone (Trittico retard) in the patients demonstrated an increase in the target variable SWS, accompanied by a reduction in the number of awakenings and stage shifts. It normalized the frequency of shifts from S2 to W and reduced the frequency of shifts from W to S1, from S1 to S2, as well as from any stage to S1 and S2. Trazodone, however, also significantly reduced the total sleep period and S2 and increased the latency to S1. Moreover, the drug increased the reduced minimal O(2 )saturation, reduced the arousal index and the PLMs-in-wake index and normalized the increased morning diastolic blood pressure. In conclusion, our study demonstrated that SPD induced significant changes in subjective and objective sleep and awakening quality, which were partially mitigated by trazodone therapy. The data on the target variable SWS support our hypothesis of a key-lock principle in the diagnosis and drug treatment of sleep disorders. Our study provided the first evidence on the usefulness of the Somnolyzer 24 x 7 and the Siesta database in clinical practice.

Adolescent↗

PubMed2005

Controlled clinical and psychometric studies on the relation between periodontitis and depressive mood.

BACKGROUND: Depressive mood is considered a risk factor for the development of periodontitis. OBJECTIVES: Investigation of the relationship between periodontitis and psychopathology utilizing psychometry (both observer- and self-rating scales). METHODS: Forty periodontitis patients were compared with 41 age- and sex-matched controls. The percentage of smokers was similar in both groups (30% versus 24.4%). Dental variables included probing depth, clinical attachment loss (CAL), radiographic loss of attachment, papillary bleeding index (PBI) and approximal plaque index (API). Psychometry comprised the Hamilton Depression Scale, the Zung Self-Rating Depression and Anxiety Scales, the von Zerssen Well-being and Complaint Scales, the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, the Quality-of-Life Index, crystallized intelligence and the Freiburg Personality Inventory (FPI). RESULTS: Multifactorial analysis of variance demonstrated increased depression and anxiety scores, reduced well-being, increased somatic complaints, deteriorated quality of life and introversion in periodontitis. Partial correlation analyses between psychometric measures and dental variables revealed positive correlations of periodontal disease severity/CAL with the depression/anxiety, subjective well-being and complaints scores, and a negative correlation with quality of life. The API was negatively correlated with social orientation, and the CAL was positively correlated with somatic complaints and introversion in the FPI. CONCLUSION: Our clinical-psychometric studies confirm depressive mood as a relevant pathogenetic factor for periodontitis.

Adult↗

PubMed2005

EEG mapping and low-resolution brain electromagnetic tomography (LORETA) in diagnosis and therapy of psychiatric disorders: evidence for a key-lock principle.

Different psychiatric disorders, such as schizophrenia with predominantly positive and negative symptomatology, major depression, generalized anxiety disorder, agoraphobia, obsessive-compulsive disorder, multi-infarct dementia, senile dementia of the Alzheimer type and alcohol dependence, show EEG maps that differ statistically both from each other and from normal controls. Representative drugs of the main psychopharmacological classes, such as sedative and non-sedative neuroleptics and antidepressants, tranquilizers, hypnotics, psychostimulants and cognition-enhancing drugs, induce significant and typical changes to normal human brain function, which in many variables are opposite to the above-mentioned differences between psychiatric patients and normal controls. Thus, by considering these differences between psychotropic drugs and placebo in normal subjects, as well as between mental disorder patients and normal controls, it may be possible to choose the optimum drug for a specific patient according to a key-lock principle, since the drug should normalize the deviant brain function. This is supported by 3-dimensional low-resolution brain electromagnetic tomography (LORETA), which identifies regions within the brain that are affected by psychiatric disorders and psychopharmacological substances.

Brain↗

PubMed2004

Sleep spindles and their significance for declarative memory consolidation.

STUDY OBJECTIVES: Functional significance of stage 2 sleep spindle activity for declarative memory consolidation. DESIGN: Randomized, within-subject, multicenter. SETTING: Weekly sleep laboratory visits, actigraphy, and sleep diary (4 weeks). PARTICIPANTS: Twenty-four healthy subjects (12 men) aged between 20 and 30 years. INTERVENTIONS: Declarative memory task or nonlearning control task before sleep. MEASUREMENT AND RESULTS: This study measured spindle activity during stage 2 sleep following a (declarative) word-pair association task as compared to a control task. Participants performed a cued recall in the evening after learning (160 word pairs) as well as in the subsequent morning after 8 hours of undisturbed sleep with full polysomnography. Overnight change in the number of recalled words, but not absolute memory performance, correlated significantly with increased spindle activity during the experimental night (r24 = .63, P < .01). Time spent in each sleep stage could not account for this relationship. CONCLUSION: A growing body of evidence supports the active role of sleep for information reprocessing. Whereas past research focused mainly on the distinct rapid eye movement and slow-wave sleep, these results indicate that increased sleep stage 2 spindle activity is related to an increase in recall performance and, thus, may reflect memory consolidation.

Adult↗

PubMed2004

EEG-mapping differences between narcolepsy patients and controls and subsequent double-blind, placebo-controlled studies with modafinil.

The aim of the present study was to investigate the role of EEG mapping as an objective and quantitative measure of vigilance in untreated and modafinil-treated narcoleptics, and compare it with the conventional neurophysiological method of the Multiple Sleep Latency Test (MSLT) and the subjective Epworth Sleepiness Scale (ESS). In 16 drug-free narcoleptics and 16 normal controls a baseline 3-min vigilance-controlled EEG (V-EEG) and a 4-min resting EEG (R-EEG) were recorded during midmorning hours. Thereafter, in a double-blind, placebo-controlled crossover design, patients were treated with a 3-week fixed titration of modafinil (200, 300, 400 mg) and placebo. EEG-mapping, MSLT and ESS measures were obtained before and at the end of the third week of therapy. Statistical overall analysis by means of the omnibus significance test demonstrated significant EEG differences between untreated patients and controls in the resting condition only (R-EEG). Subsequent univariate analysis revealed an increase in absolute and relative theta power, a decrease in alpha-2 and beta power as well as a slowing of the dominant frequency and the centroids of the alpha, beta and total power spectrum and thus objectified a vigilance decrement in narcolepsy. Modafinil 400 mg/d significantly improved vigilance as compared with placebo (p < or = 0.01), inducing changes opposite to the aforementioned baseline differences (key-lock principle). The MSLT and the ESS also improved under modafinil as compared with placebo, but changes were less consistent. Spearman rank correlations revealed the highest correlations between EEG mapping and the ESS, followed by those between EEG mapping and the MSLT, while the lowest correlation was found between the MSLT and the ESS. In conclusion, EEG mapping is a valuable instrument for measuring vigilance decrements in narcolepsy and their improvement under psychostimulant treatment.

Adult↗

PubMed2004

EEG mapping in patients with social phobia.

Recent studies have suggested an information-processing bias in social phobia (SP). Little is known about the electrophysiological correlates of anxiety in SP. The aim of the present study was to investigate the quantitative electroencephalogram (EEG) in 25 drug-free patients with SP as compared with age- and sex-matched normal controls and to correlate anxiety and depressive symptoms with EEG data. EEG was recorded under vigilance-controlled and resting conditions. The Spielberger State and Trait Anxiety Scale (STAI) and the Beck Depression Inventory (BDI) were administered to assess anxiety and depression levels. Multivariate analysis of variance revealed significant differences between patients and controls, specifically frontopolarly and right centrally. Statistical analysis demonstrated a decrease in absolute and relative delta, theta power, alpha-adjacent slow-beta and fast beta power and an increase in absolute and relative intermediate beta power, as well as an acceleration of the total centroid and a slowing in beta centroid and its variability. Trait anxiety and depression scores correlated positively with the dominant alpha frequency and the alpha centroid, and negatively with absolute theta and slow alpha power as well as with the centroid of the delta/theta frequency band. In conclusion, EEG mapping in patients with SP revealed significant differences from normal controls suggesting a hyperarousal as a pathogenetic factor of anxiety.

Adult↗

PubMed2004

P300 event-related potentials and cognitive function in social phobia.

The aim of the study was to investigate abnormalities of event-related potentials (ERPs) in social phobia patients indicating deficits in speed and amount of perceptual and cognitive resources as well as relationships between ERPs and cognitive functioning. ERPs were recorded from 19 EEG leads in a two-tone oddball paradigm in medication-free patients with DSM-IV social phobia (n=25) and in age- and sex-matched healthy controls (HC). Neuropsychological test performance was administered. Compared with the HC group, patients with social phobia showed reductions in N1 at temporal leads, N2 and P300 amplitudes, predominantly centroparietally, and longer P300 latencies. The observed P300 latency prolongation was associated with reduced Non-Verbal Learning Test (NVLT) but not the Wisconsin Card Sorting Test (WCST) scores. The reduction in N1 amplitude indicates an impairment in perceptual processing. The reduced P300 amplitudes may reflect reduced cognitive resources for the evaluation of relevant information. The increased P300 latency, indicating longer stimulus evaluation time, was correlated to deficits in learning processes as measured by the Non-Verbal Learning Test but not to executive function as measured by the Wisconsin Card Sorting Test. It may therefore be concluded that social phobia patients show deficits in cognitive information processing as reflected by ERPs.

Adult↗

PubMed2004

Sleep microstructure and neurodegeneration as measured by [123I]beta-CIT SPECT in treated patients with Parkinson's disease.

OBJECTIVES: Along with spindles, K-complexes are well known hallmarks of stage 2 (S2) sleep. However, little is known about their quantity in S2 sleep of patients with Parkinson's disease (PD). SETTING: Sleep laboratory, Department of Neurology, University of Vienna, Austria. PATIENTS AND METHODS: Whole-night polysomnography (PSG) was performed in twelve treated PD patients and ten healthy controls without history of sleep complaints. The quantity of spontaneous K-complexes, K-alpha-complexes, and sleep spindles in one hour S2 sleep, distributed in four epochs of 15 minutes all through the night, were visually selected and analysed. The quantity and the temporal course of these phasic events were compared with the quantity in age-matched healthy controls. Nine of the twelve PD patients underwent [123I]beta-CIT SPECT for calculating dopamine transporter binding in the striatum and serotonin transporter density in the thalamus-hypothalamus region. RESULTS: There was no difference between the quantity of K-complexes, K-alpha-complexes, and sleep spindles in PD patients and in the healthy control group. K-complexes but not sleep spindles decreased over the night in both groups. The number of sleep spindles did not correlate with the dopamine transporter binding in the striatum or the serotonin binding in the thalamic/hypothalamic region. CONCLUSION: K-complexes and sleep spindles are not reduced and do not seem to be related to the degree of dopaminergic degeneration in treated PD patients.

Aged↗

PubMed2004

Brain regions activated during an auditory discrimination task in insomniac postmenopausal patients before and after hormone replacement therapy: low-resolution brain electromagnetic tomography applied to event-related potentials.

Electrical sources of auditory event-related potentials (ERPs) determined by means of low-resolution brain electromagnetic tomography (LORETA) in 48 unmedicated insomniac postmenopausal patients aged between 46 and 67 years were compared with those obtained in 48 age-matched normal female controls. Subsequently, the patients were included in a double-blind, placebo-controlled, comparative, randomized 3-arm trial phase - Climodien 2/3 [estradiol valerate (EV) 2 mg + the progestin dienogest 3 mg] was compared with EV 2 mg and placebo - followed by an open-label phase in which all of them received Climodien 2/2 (EV 2 mg + dienogest 2 mg). The double-blind and the open-label phase lasted 2 months. ERPs were recorded from 19 EEG leads in a two-tone oddball paradigm and electrical sources of standard N1 and P2 as well as target N2 and P300 components were estimated. In both patients and controls, LORETA revealed an activation of the superior temporal gyrus [auditory cortex, Brodmann areas (BA) 41, 42, 22] for all four components. For standard P2, an additional activation was observed medially parietally in the precuneus (BA 7, 5). For target N2, also a medial frontal source (BA 9, 10, 32) was identified. Finally, for the target P300 component - in addition to the aforementioned sources - activations in the prefrontal cortex (BA 9, 10, 46, 47), the inferior parietal cortex (supramarginal gyrus, BA 40, 39) and the posterior cingulum (BA 31) were found. Thus, patients and controls did not differ in the structural processes engaged in these fundamental aspects of information processing. However, patients demonstrated significantly reduced source strength - for standard ERP components predominantly in the temporal lobe and for target components predominantly in the frontal lobe, indicating reduced energetic resources available for perceptual and cognitive demands of the discrimination task. While, as compared with placebo, estrogen alone had only minor effects on ERP source strength, Climodien generally increased the impressed current density at the ERP peak latencies, predominantly in the temporal lobe, indicating an increased stimulus-induced cortical arousal in the primary and higher-order auditory cortex. Specifically, Climodien enhanced P300 source strength in the left middle temporal gyrus and in the left superior frontal gyrus, brain regions that on the one hand have been shown to be affected by hormone therapy in positron emission tomography and functional magnetic resonance neuroimaging studies and that on the other hand are among those critical for encoding and memory processes.

Acoustic Stimulation↗

PubMed2004

Effects of the South American psychoactive beverage ayahuasca on regional brain electrical activity in humans: a functional neuroimaging study using low-resolution electromagnetic tomography.

Ayahuasca, a South American psychotropic plant tea obtained from Banisteriopsis caapi and Psychotria viridis, combines monoamine oxidase-inhibiting beta-carboline alkaloids with N,N-dimethyltryptamine (DMT), a psychedelic agent showing 5-HT(2A) agonist activity. In a clinical research setting, ayahuasca has demonstrated a combined stimulatory and psychedelic effect profile, as measured by subjective effect self-assessment instruments and dose-dependent changes in spontaneous brain electrical activity, which parallel the time course of subjective effects. In the present study, the spatial distribution of ayahuasca-induced changes in brain electrical activity was investigated by means of low-resolution electromagnetic tomography (LORETA). Electroencephalography recordings were obtained from 18 volunteers after the administration of a dose of encapsulated freeze-dried ayahuasca containing 0.85 mg DMT/kg body weight and placebo. The intracerebral power density distribution was computed with LORETA from spectrally analyzed data, and subjective effects were measured by means of the Hallucinogen Rating Scale (HRS). Statistically significant differences compared to placebo were observed for LORETA power 60 and 90 min after dosing, together with increases in all six scales of the HRS. Ayahuasca decreased power density in the alpha-2, delta, theta and beta-1 frequency bands. Power decreases in the delta, alpha-2 and beta-1 bands were found predominantly over the temporo-parieto-occipital junction, whereas theta power was reduced in the temporomedial cortex and in frontomedial regions. The present results suggest the involvement of unimodal and heteromodal association cortex and limbic structures in the psychological effects elicited by ayahuasca.

Administration, Oral↗

PubMed2003

Quality of life in nonorganic and organic sleep disorders: II. Correlation with objective and subjective quality of sleep and awakening.

OBJECTIVE: The purpose of this study of 100 patients suffering from sleep-disorders was to determine correlations between their subjective health-related quality of life (HRQoL) and objective variables in sleep initiation and maintenance, sleep architecture, objective quality of awakening, psychophysiological parameters and subjective quality of sleep and awakening. METHODS: Objective measurements were obtained from overnight diagnostic polysomnography. Subjective HRQoL was determined from the Quality of Life Index (QLI, Mezzich and Cohen) completed prior to the adaptation night. Other measurements included subjective and objective quality of sleep and awakening (psychometry) the evening before and morning after polysomnographic investigations. RESULTS: 63% of the patients were suffering from nonorganic and 37% from organic sleep disorders (SDs). Within the first group, nonorganic insomnia predominated; within the second, sleep apnea. Subjective HRQoL correlated well with subjective sleep and awakening quality, especially in nonorganic SDs. There were only a few correlations of objective measurements with subjective HRQoL: in the total group of SD patients HRQoL correlated with sleep stage S2, and in nonorganic SDs with attention scores and psychophysiological measurements (mainly the pulse rate in the evening and morning). CONCLUSION: Our findings suggest only a weak relationship between objective sleep variables and subjective HRQoL in both organic and nonorganic SDs. However, we found various significant correlations of HRQoL with subjective measurements of sleep, especially in nonorganic SDs.

Adult↗

PubMed2003

Quality of life in nonorganic and organic sleep disorders: I. Comparison with normative data.

Subjective health-related quality of life (HRQoL) was investigated in 100 patients with disturbed sleep (39 women aged 52 +/- 13 years and 61 men aged 53 +/- 10 years) referred to the sleep laboratory and compared with HRQoL in 100 normal healthy adults. Measurements included the Quality of Life Index (QLI) (Mezzich and Cohen), and objective (polysomnographic) and subjective (psychometric) quality of sleep and awakening. Statistical analysis (Mann-Whitney U-test) showed HRQoL to be significantly reduced in sleep disorders (SDs), with a more pronounced reduction in nonorganic than in organic SDs. Patients with nonorganic hypersomnia were more disturbed than those with nonorganic insomnia. Within organic SDs, patients with apnea were more disturbed than those with obstructive snoring. Out of ten elementary HRQoL components, seven were disturbed in SDs: physical well-being, psychological well-being, self-care and independent functioning, occupational functioning, interpersonal functioning, personal fulfillment, and overall quality of life. No differences between patients and normal healthy subjects where found in the components social support, community and services support or spiritual fulfillment. Patients suffering from nonorganic SDs had significantly worse scores in physical and psychological well-being and overall quality of life than those with organic SDs. Patients with both SDs and additional diagnoses of affective disorders had more profoundly reduced HRQoL than those with anxiety disorders. Follow-up of 51 patients (31 with nonorganic SDs and 20 with organic SDs) one year after sleep laboratory investigation and subsequent treatment found significantly improved HRQoL compared with pre-treatment. Moreover, patients diagnosed and treated in the sleep laboratory showed lower re-hospitalization rats.

Activities of Daily Living↗

PubMed2003

Effects of hormone replacement therapy on perceptual and cognitive event-related potentials in menopausal insomnia.

The influence of a combined estrogen-progestin regimen (Climodien, Lafamme) on auditory event-related potentials (ERPs) was investigated in a double-blind, placebo-controlled, comparative, randomized 3-arm trial phase (Climodien 2/3=estradiol valerate 2 mg+the progestin dienogest 3 mg, EV=estradiol valerate 2 mg, and placebo), followed by an open-label phase in which all patients received Climodien 2/2 (estradiol valerate 2 mg+dienogest 2 mg). Both the double-blind and the open-label phase lasted 2 months. ERPs were recorded from 19 EEG leads in a two-tone odd-ball paradigm in 49 patients aged between 46 and 67 yr with the diagnosis of insomnia (G 47.0) related to postmenopausal syndrome (N 95.1). Climodien reduced standard N1 and target P300 latencies as compared to placebo, while EV did not affect N1 latency but similarly reduced P300 latency. Climodien increased N1, P2 and P300 amplitudes dose-dependently, predominantly at frontal leads. Estrogen alone had only minor effects on ERP amplitudes. The shortening of standard N1 latency and enhancement of N1 and P2 amplitudes indicates a positive effect of Climodien on perceptual processing, most likely due to vigilance improvements also observed in EEG mapping. Concerning target P300, it seems that estradiol is responsible for the improvement in stimulus evaluation time, as reflected by the shortening of the peak latency, while dienogest seems to account for the improvement in cognitive information processing capacity, whereby 3 mg induced a more pronounced augmentation of P300 amplitudes than 2 mg. Based on the spatial distribution of this increase, it can be speculated that Climodien mainly affects the more frontally distributed P3a subcomponent, which is associated with attention and orientation. Furthermore, the observed changes in ERP-components are consistent with recent studies showing significant positive effects of hormone replacement therapy on cholinergic functions. Thus, Climodien seems to be of interest in preventing cognitive decline and treating cognitive disorders in postmenopausal women. Indeed, there is increasing evidence of beneficial effects of estrogen in dementia. Our present findings suggest that the estrogen effects may be augmented by dienogest.

Affect↗