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We explored and refined the hypothesis that during a first episode of acute schizophrenia a disorganization of brain functioning is present. A novel EEG measure was introduced, Global Field Synchronization (GFS), that estimates functional connectivity of brain processes in different EEG frequency bands. The measure was applied to EEG's from 11 never-treated, first-episode, young patients with an acute, positive, schizophrenic symptomatology and from 19 controls, residing in Bern, Switzerland. In comparison to age- and sex- matched controls, patients had significantly decreased GFS in the theta EEG frequency band, indicating a loosened functional connectivity of processes in this frequency. The result was confirmed in an independent, comparable patient group from Osaka, Japan (9 patients and 9 controls), thus making a total of 20 analyzed patients. Previous EEG research in healthy, awake subjects indicated a positive correlation of theta activity with memory functions. Thus, our result suggests a loss of mutual interdependence of memory functions in patients with acute schizophrenia, which agrees well with previous reports of working memory dysfunction in schizophrenia.

We describe a simple technique to measure sulfide in fecal homogenates (or any other liquid milieu), which involves acidification followed by the G.C. measurement of H2S in a gas space equilibrated with a small quantity of homogenate. An internal standard of Zn35S added to the homogenate permits correction for incomplete recovery of H2S in the gas space. The use of a sulfur chemiluminescence detector, which specifically and sensitively responds to sulfur-containing compounds, greatly facilitates this measurement.

Brain electrical microstates represent spatial configurations of scalp recorded brain electrical activity and are considered to be the basic elements of stepwise processing of information in the brain. In the present study, the hypothesis of a temporo-limbic dysfunction in panic disorder (PD) was tested by investigating the topographic descriptors of brain microstates, in particular the one corresponding to the Late Positive Complex (LPC), an event-related potential (ERP) component with generators in these regions. ERPs were recorded in PD patients and matched healthy subjects during a target detection task, in a central (CC) and a lateral condition (LC). In the CC, a leftward shift of the LPC microstate positive centroid was observed in the patients with PD versus the healthy control subjects. In the LC, the topographic descriptor of the first microstate showed a rightward shift, while those of both the second and the fourth microstate, corresponding to the LPC, revealed a leftward shift in the PD patients versus the healthy control subjects. These findings indicate an overactivation of the right hemisphere networks involved in early visual processing and a hypoactivation of the right hemisphere circuits involved in LPC generators in PD. In line with this interpretation, the abnormal topography of the LPC microstate, observed in the CC, was associated with a worse performance on a test exploring right temporo-hippocampal functioning. Topographical abnormalities found for the LPC microstate in the LC were associated with a higher number of panic attacks, suggesting a pathogenetic role of the right temporo-hippocampal dysfunction in PD.

The neurocognitive processes underlying the formation and maintenance of paranormal beliefs are important for understanding schizotypal ideation. Behavioral studies indicated that both schizotypal and paranormal ideation are based on an overreliance on the right hemisphere, whose coarse rather than focussed semantic processing may favor the emergence of 'loose' and 'uncommon' associations. To elucidate the electrophysiological basis of these behavioral observations, 35-channel resting EEG was recorded in pre-screened female strong believers and disbelievers during resting baseline. EEG data were subjected to FFT-Dipole-Approximation analysis, a reference-free frequency-domain dipole source modeling, and Regional (hemispheric) Omega Complexity analysis, a linear approach estimating the complexity of the trajectories of momentary EEG map series in state space. Compared to disbelievers, believers showed: more right-located sources of the beta2 band (18.5-21 Hz, excitatory activity); reduced interhemispheric differences in Omega complexity values; higher scores on the Magical Ideation scale; more general negative affect; and more hypnagogic-like reveries after a 4-min eyes-closed resting period. Thus, subjects differing in their declared paranormal belief displayed different active, cerebral neural populations during resting, task-free conditions. As hypothesized, believers showed relatively higher right hemispheric activation and reduced hemispheric asymmetry of functional complexity. These markers may constitute the neurophysiological basis for paranormal and schizotypal ideation.

Objectives: Although behavioral studies have demonstrated that normative affective traits modulate the processing of facial and emotionally charged stimuli, direct electrophysiological evidence for this modulation is still lacking., Methods: Event-related potential (ERP) data associated with personal, traitlike approach- or withdrawal-related attitude (assessed post-recording and 14 months later) were investigated in 18 subjects during task-free (i.e. unrequested, spontaneous) emotional evaluation of faces. Temporal and spatial aspects of 27 channel ERP were analyzed with microstate analysis and low resolution electromagnetic tomography (LORETA), a new method to compute 3 dimensional cortical current density implemented in the Talairach brain atlas., Results: Microstate analysis showed group differences 132-196 and 196-272 ms poststimulus, with right-shifted electric gravity centers for subjects with negative affective attitude. During these (over subjects reliably identifiable) personality-modulated, face-elicited microstates, LORETA revealed activation of bilateral occipito-temporal regions, reportedly associated with facial configuration extraction processes. Negative compared to positive affective attitude showed higher activity right temporal; positive compared to negative attitude showed higher activity left temporo-parieto-occipital., Conclusions: These temporal and spatial aspects suggest that the subject groups differed in brain activity at early, automatic, stimulus-related face processing steps when structural face encoding (configuration extraction) occurs. In sum, the brain functional microstates associated with affect-related personality features modulate brain mechanisms during face processing already at early information processing stages.

Nondemented Parkinson's disease (PD) patients showed increased amplitude of event-related potential component P3. We recorded 18-channel spontaneous eyes-closed resting EEG and auditory oddball event-related potentials in 29 PD patients and 11 age-matched controls. Combining Mini-Mental State Examination score and oddball P3 counting performance, 15 patients were intellectually normal, 7 moderately, and 7 severely demented. P3 and N1 amplitude and latency, mean amplitude of 1,024 ms post-stimulus (separate after rare and after frequent stimuli), and resting EEG total power for 40 s were computed, and linearly regressed for age, sex, and L-dopa dosage. In nondemented PD patients, increased P3 amplitude was confirmed, but N1 amplitude and mean amplitude after rare and frequent stimuli were also increased as well as - most important - resting EEG total power. With increasing dementia, amplitude and power decreased, and P3 latency increased. Task demands cannot explain increased P3 amplitude, since similarly increased EEG total power was found during no-task resting. Prospective studies must determine whether P3 amplitude and EEG power in nondemented PD patients can serve as predictors of dementia., (Copyright 2000 S. Karger AG, Basel)

Global complexity of 47-channel resting electroencephalogram (EEG) of healthy young volunteers was studied after intake of a single dose of a nootropic drug (piracetam, Nootropil UCB Pharma) in 12 healthy volunteers. Four treatment levels were used: 2.4, 4.8, 9.6 g piracetam and placebo. Brain electric activity was assessed through Global Dimensional Complexity and Global Omega-Complexity as quantitative measures of the complexity of the trajectory of multichannel EEG in state space. After oral ingestion (1-1.5 h), both measures showed significant decreases from placebo to 2.4 g piracetam. In addition, Global Dimensional Complexity showed a significant return to placebo values at 9.6 g piracetam. The results indicate that a single dose of piracetam dose-dependently affects the spontaneous EEG in normal volunteers, showing effects at the lowest treatment level. The decreased EEG complexity is interpreted as increased cooperativity of brain functional processes.

Functional imaging of brain electrical activity was performed in nine acute, neuroleptic-naive, first-episode, productive patients with schizophrenia and 36 control subjects. Low-resolution electromagnetic tomography (LORETA, three-dimensional images of cortical current density) was computed from 19-channel electroencephalographic (EEG) activity obtained under resting conditions, separately for the different EEG frequencies. Three patterns of activity were evident in the patients: (1) an anterior, near-bilateral excess of delta frequency activity; (2) an anterior-inferior deficit of theta frequency activity coupled with an anterior-inferior left-sided deficit of alpha-1 and alpha-2 frequency activity; and (3) a posterior-superior right-sided excess of beta-1, beta-2 and beta-3 frequency activity. Patients showed deviations from normal brain activity as evidenced by LORETA along an anterior-left-to-posterior-right spatial axis. The high temporal resolution of EEG makes it possible to specify the deviations not only as excess or deficit, but also as inhibitory, normal and excitatory. The patients showed a dis-coordinated brain functional state consisting of inhibited prefrontal/frontal areas and simultaneously overexcited right parietal areas, while left anterior, left temporal and left central areas lacked normal routine activity. Since all information processing is brain-state dependent, this dis-coordinated state must result in inadequate treatment of (externally or internally generated) information.

We investigated whether different, personality-related affective attitudes are associated with different brain electric field (EEG) sources before any emotional challenge (stimulus exposure). A 27-channel EEG was recorded in 15 subjects during eyes-closed resting. After recording, subjects rated 32 images of human faces for affective appeal. The subjects in the first (i.e., most negative) and fourth (i.e., most positive) quartile of general affective attitude were further analyzed. The EEG data (mean=25+/-4. 8 s/subject) were subjected to frequency-domain model dipole source analysis (FFT-Dipole-Approximation), resulting in 3-dimensional intracerebral source locations and strengths for the delta-theta, alpha, and beta EEG frequency band, and for the full range (1.5-30 Hz) band. Subjects with negative attitude (compared to those with positive attitude) showed the following source locations: more inferior for all frequency bands, more anterior for the delta-theta band, more posterior and more right for the alpha, beta and 1.5-30 Hz bands. One year later, the subjects were asked to rate the face images again. The rating scores for the same face images were highly correlated for all subjects, and original and retest affective mean attitude was highly correlated across subjects. The present results show that subjects with different affective attitudes to face images had different active, cerebral, neural populations in a task-free condition prior to viewing the images. We conclude that the brain functional state which implements affective attitude towards face images as a personality feature exists without elicitors, as a continuously present, dynamic feature of brain functioning., (Copyright 1999 Elsevier Science B.V.)

Momentary brain electric field configurations are manifestations of momentary global functional states of the brain. Field configurations tend to persist over some time in the sub-second range ("microstates") and concentrate within few classes of configurations. Accordingly, brain field data can be reduced efficiently into sequences of re-occurring classes of brain microstates, not overlapping in time. Different configurations must have been caused by different active neural ensembles, and thus different microstates assumably implement different functions. The question arises whether the aberrant schizophrenic mentation is associated with specific changes in the repertory of microstates. Continuous sequences of brain electric field maps (multichannel EEG resting data) from 9 neuroleptic-naive, first-episode, acute schizophrenics and from 18 matched controls were analyzed. The map series were assigned to four individual microstate classes; these were tested for differences between groups. One microstate class displayed significantly different field configurations and shorter durations in patients than controls; degree of shortening correlated with severity of paranoid symptomatology. The three other microstate classes showed no group differences related to psychopathology. Schizophrenic thinking apparently is not a continuous bias in brain functions, but consists of intermittent occurrences of inappropriate brain microstates that open access to inadequate processing strategies and context information

The present study shows that different neural activity during mental imagery and abstract mentation can be assigned to well-defined steps of the brain's information-processing. During randomized visual presentation of single, imagery-type and abstract-type words, 27 channel event-related potential (ERP) field maps were obtained from 25 subjects (sequence-divided into a first and second group for statistics). The brain field map series showed a sequence of typical map configurations that were quasi-stable for brief time periods (microstates). The microstates were concatenated by rapid map changes. As different map configurations must result from different spatial patterns of neural activity, each microstate represents different active neural networks. Accordingly, microstates are assumed to correspond to discrete steps of information-processing. Comparing microstate topographies (using centroids) between imagery- and abstract-type words, significantly different microstates were found in both subject groups at 286-354 ms where imagery-type words were more right-lateralized than abstract-type words, and at 550-606 ms and 606-666 ms where anterior-posterior differences occurred. We conclude that language-processing consists of several, well-defined steps and that the brain-states incorporating those steps are altered by the stimuli's capacities to generate mental imagery or abstract mentation in a state-dependent manner.

Background: Schizophrenic symptoms commonly are felt to indicate a loosened coordination, i.e. a decreased connectivity of brain processes., Methods: To address this hypothesis directly, global and regional multichannel electroencephalographic (EEG) complexities (omega complexity and dimensional complexity) and single channel EEG dimensional complexities were calculated from 19-channel EEG data from 9 neuroleptic-naive, first-break, acute schizophrenics and 9 age- and sex-matched controls. Twenty artifact-free 2 second EEG epochs during resting with closed eyes were analyzed (2-30 Hz bandpass, average reference for global and regional complexities, local EEG gradient time series for single channels)., Results: Anterior regional Omega-Complexity was significantly increased in schizophrenics compared with controls (p < 0.001) and anterior regional Dimensional Complexity showed a trend for increase. Single channel Dimensional Complexity of local gradient waveshapes was prominently increased in the schizophrenics at the right precentral location (p = 0.003)., Conclusions: The results indicate a loosened cooperativity or coordination (vice versa: an increased independence) of the active brain processes in the anterior brain regions of the schizophrenics.

Prompted reports of recall of spontaneous, conscious experiences were collected in a no-input, no-task, no-response paradigm (30 random prompts to each of 13 healthy volunteers). The mentation reports were classified into visual imagery and abstract thought. Spontaneous 19-channel brain electric activity (EEG) was continuously recorded, viewed as series of momentary spatial distributions (maps) of the brain electric field and segmented into microstates, i.e. into time segments characterized by quasi-stable landscapes of potential distribution maps which showed varying durations in the sub-second range. Microstate segmentation used a data-driven strategy. Different microstates, i.e. different brain electric landscapes must have been generated by activity of different neural assemblies and therefore are hypothesized to constitute different functions. The two types of reported experiences were associated with significantly different microstates (mean duration 121 ms) immediately preceding the prompts; these microstates showed, across subjects, for abstract thought (compared to visual imagery) a shift of the electric gravity center to the left and a clockwise rotation of the field axis. Contrariwise, the microstates 2 s before the prompt did not differ between the two types of experiences. The results support the hypothesis that different microstates of the brain as recognized in its electric field implement different conscious, reportable mind states, i.e. different classes (types) of thoughts (mentations); thus, the microstates might be candidates for the 'atoms of thought'.

Covert brain activity related to task-free, spontaneous (i.e. unrequested), emotional evaluation of human face images was analysed in 27-channel averaged event-related potential (ERP) map series recorded from 18 healthy subjects while observing random sequences of face images without further instructions. After recording, subjects self-rated each face image on a scale from "liked" to "disliked". These ratings were used to dichotomize the face images into the affective evaluation categories of "liked" and "disliked" for each subject and the subjects into the affective attitudes of "philanthropists" and "misanthropists" (depending on their mean rating across images). Event-related map series were averaged for "liked" and "disliked" face images and for "philanthropists" and "misanthropists". The spatial configuration (landscape) of the electric field maps was assessed numerically by the electric gravity center, a conservative estimate of the mean location of all intracerebral, active, electric sources. Differences in electric gravity center location indicate activity of different neuronal populations. The electric gravity center locations of all event-related maps were averaged over the entire stimulus-on time (450 ms). The mean electric gravity center for disliked faces was located (significant across subjects) more to the right and somewhat more posterior than for liked faces. Similar differences were found between the mean electric gravity centers of misanthropists (more right and posterior) and philanthropists. Our neurophysiological findings are in line with neuropsychological findings, revealing visual emotional processing to depend on affective evaluation category and affective attitude, and extending the conclusions to a paradigm without directed task.

We investigated brain electric field signatures of subjective feelings after chewing regular gum or gum base without flavor. 19-channel eyes-closed EEG from 20 healthy males before and after 5 minutes of chewing the two gum types in random sequence was source modeled in the frequency domain using the FFT-Dipole-Approximation. 3-dimensional brain locations and strengths (Global Field Power, GFP) of the equivalent sources of five frequency bands were computed as changes from pre-chewing baseline. Gum types differed (ANOVA) in pre-post changes of source locations for the alpha-2 band (to anterior and right after regular gum, opposite after gum base) and beta-2 band (to anterior and inferior after regular gum, opposite after gum base), and of GFP for delta-theta, alpha-2 and beta-1 (regular gum: increase. gum base: decrease). Subjective feeling changed to more positive values after regular gum than gum base (ANOVA).--Thus, chewing gum with and without taste-smell activates different brain neuronal populations.

Background: The literature is inconclusive on the role of antidepressant medications in treating drug dependence. Studies have either not focused on depressed patients or have selected patients with depressive disorders based on cross-sectional symptoms rather than a syndromal diagnosis. A clinical trial of an antidepressant was, therefore, conducted on drug-dependent patients with syndromal depression., Methods: Patients receiving methadone hydrochloride maintenance treatment were selected if they met the criteria for a DSM-III-R depressive disorder that was chronologically primary, had persisted during a past abstinent period or was long-standing, and persisted during at least 1 month of stable methadone treatment. Subjects were randomized to a 12-week, double-blind, placebo-controlled trial of imipramine hydrochloride. A favorable response was defined as a Clinical Global Impression scale score for depression of 2 ("much improved") or 1 ("very much improved") and at least a 75% reduction in self-reported drug or alcohol use or abstinence., Results: One hundred thirty-seven patients were randomized, and 84 completed a minimum adequate trial of at least 6 weeks. Among the 84 adequately treated patients, 57% (24/42) receiving imipramine were rated as responders compared with 7% (3/42) receiving placebo (P < .001). On measures of mood, there was a robust effect of imipramine. Imipramine was superior to placebo on some self-reported measures of substance use and craving, and mood improvement was associated with improvement in self-reported substance use. However, few patients achieved urine-confirmed abstinence., Conclusions: Imipramine was an effective antidepressant in patients receiving methadone who were selected via syndromal criteria for depressive illness. Imipramine may reduce substance abuse among patients whose mood improves; however, this effect was less robust.

Brain electric activity is viewed as sequences of momentary maps of potential distribution. Frequency-domain source modeling, estimation of the complexity of the trajectory of the mapped brain field distribution in state space, and microstate parsing were used as analysis tools. Input-presentation as well as task-free (spontaneous thought) data collection paradigms were employed. We found: Alpha EEG field strength is more affected by visualizing mentation than by abstract mentation, both input-driven as well as self-generated. There are different neuronal populations and brain locations of the electric generators for different temporal frequencies of the brain field. Different alpha frequencies execute different brain functions as revealed by canonical correlations with mentation profiles. Different modes of mentation engage the same temporal frequencies at different brain locations. The basic structure of alpha electric fields implies inhomogeneity over time-alpha consists of concatenated global microstates in the sub-second range, characterized by quasi-stable field topographics, and rapid transitions between the microstates. In general, brain activity is strongly discontinuous, indicating that parsing into field landscape-defined microstates is appropriate. Different modes of spontaneous and induced mentation are associated with different brain electric microstates; these are proposed as candidates for psychophysiological 'atoms of thought'.

27-Channel EEG potential map series were recorded from 12 normals with closed and open eyes. Intracerebral dipole model source locations in the frequency domain were computed. Eye opening (visual input) caused centralization (convergence and elevation) of the source locations of the seven frequency bands, indicative of generalized activity; especially, there was clear anteriorization of alpha-2 (10.5-12 Hz) and beta-2 (18.5-21 Hz) sources (alpha-2 also to the left). Complexity of the map series' trajectories in state space (assessed by Global Dimensional Complexity and Global OMEGA Complexity) increased significantly with eye opening, indicative of more independent, parallel, active processes. Contrary to PET and fMRI, these results suggest that brain activity is more distributed and independent during visual input than after eye closing (when it is more localized and more posterior).

Global complexity of spontaneous brain electric activity was studied before and after chewing gum without flavor and with 2 different flavors. One-minute, 19-channel, eyes-closed electroencephalograms (EEG) were recorded from 20 healthy males before and after using 3 types of chewing gum: regular gum containing sugar and aromatic additives, gum containing 200 mg theanine (a constituent of Japanese green tea), and gum base (no sugar, no aromatic additives); each was chewed for 5 min in randomized sequence. Brain electric activity was assessed through Global Omega (Omega)-Complexity and Global Dimensional Complexity (GDC), quantitative measures of complexity of the trajectory of EEG map series in state space; their differences from pre-chewing data were compared across gum-chewing conditions. Friedman Anova (p < 0.043) showed that effects on Omega-Complexity differed significantly between conditions and differences were maximal between gum base and theanine gum. No differences were found using GDC. Global Omega-Complexity appears to be a sensitive measure for subtle, central effects of chewing gum with and without flavor.

Chronic pain is a significant public health problem and frustrating for everyone affected by it. Psychiatrists should take an active role in the care of patients with chronic pain. They no longer should wait to make a psychiatric diagnosis by exclusion in the patient who has failed to respond to multiple treatments over a period of years. Recent advances in the treatment of chronic pain include the diagnosis and treatment of psychiatric comorbidity, the application of primary psychiatric treatments to chronic pain, and the development of interdisciplinary efforts to provide comprehensive health care to the patient suffering with chronic pain.

Brain processing of grammatical word class was studied analyzing event-related potential (ERP) brain fields. Normal subjects observed a randomized sequence of single German nouns and verbs on a computer screen, while 20-channel ERP field map series were recorded separately for both word classes. Spatial microstate analysis was applied, based on the observation that series of ERP maps consist of epochs of quasi-stable map landscapes and based on the rationale that different map landscapes must have been generated by different neural generators and thus suggest different brain functions. Space-oriented segmentation of the mean map series identified nine successive, different functional microstates, i.e., steps of brain information processing characterized by quasi-stable map landscapes. In the microstate from 116 to 172 msec, noun-related maps differed significantly from verb-related maps along the left-right axis. The results indicate that different neural populations represent different grammatical word classes in language processing, in agreement with clinical observations. This word class differentiation as revealed by the spatial-temporal organization of neural activity occurred at a time after word input compatible with speed of reading.

Menarche age was assessed in 93 adolescent females in a sample of public schools in East Hawaii. Native Hawaiian girls had significantly lower reported age at menarche than non-Hawaiian classmates. Age at menarche was significantly correlated with total fatness as measured by the sum of six skinfolds in girls who had reached menarche at least 2 years previous to measurement. When fatness was controlled in comparisons, the ethnic differences were not significant. Fat distribution, independent of fatness, was also significantly related to age at menarche. Socioeconomic, cultural, and admixture variables were not significantly related to age at menarche. Adiposity appears to be both a cause and a consequence of early age at menarche, with the relationship dependent on the elapsed time between menarche and measurement. This suggests that studies relating body composition to age at menarche must carefully control for the time interval between measurement and the date of menarche.

Reports on left-lateralized abnormalities of component P300 of event-related brain potentials (ERP) in schizophrenics typically did not vary task difficulties. We collected 16-channel ERP in 13 chronic, medicated schizophrenics (25 +/- 4.9 years) and 13 matched controls in a visual P300 paradigm with targets defined by one or two stimulus dimensions (C1: color; C2: color and tilt); subjects key-pressed to targets. The mean target-ERP map landscapes were assessed numerically by the locations of the positive and negative map-area centroids. The centroids time-space trajectories were searched for the P300 microstate landscape defined by the positive centroid posterior of the negative centroid. At P300 microstate centre latencies in C1, patients' maps tended to a right shift of the positive centroid (p < 0.10); in C2 the anterior centroid was more posterior (p < 0.07) and the posterior (positive) centroid more anterior (p < 0.03), but without left-right difference. Duration of P300 microstate in C2 was shorter in patients (232 vs 347 ms; p < 0.03) and the latency of maximal strength of P300 microstate increased significantly in patients (C1: 459 vs 376 ms; C2: 585 vs 525 ms). In summary only the one-dimensional task C1 supported left-sided abnormalities; the two-dimensional task C2 produced abnormal P300 microstate map landscapes in schizophrenics, but no abnormal lateralization. Thus, information processing involved clearly aberrant neural populations in schizophrenics, different when processing one and two stimulus dimensions. The lack of lateralization in the two-dimensional task supported the view that left-temporal abnormality in schizophrenics is only one of several task-dependent aberrations.

A 12-week placebo-controlled, randomized clinical trial was undertaken to evaluate imipramine as a treatment for cocaine abuse, and to examine whether its effect may be limited to subgroups defined by route of use or by diagnosis of depression. One-hundred thirteen patients were randomized, stratified by route of use and depression. All patients received weekly individual counseling. Compared to placebo the imipramine group showed greater reductions in cocaine craving, cocaine euphoria, and depression, but the effect of imipramine on cocaine use was less clear. A favorable response, defined as at least 3 consecutive, urine-confirmed, cocaine-free weeks was achieved by 19% (11/59) of patients on imipramine compared to 7% (4/54) on placebo (P < 0.09). The imipramine effect was greater among nasal users--33% (9/27) response on imipramine vs. 5% (1/22) on placebo (P < 0.02). Response was also more frequent, but not significantly so, among depressed users on imipramine (26%, 10/38) than on placebo (13%, 4/31) (P < 0.19). Response rates were low in intravenous and freebase users and those without depression. Considered together with the literature on desipramine, these data suggest tricyclic antidepressants are not promising as a mainstay of treatment for unselected cocaine abusers. However, tricyclics may be useful for selected cocaine abusers with comorbid depression or intranasal use, or in conjunction with a more potent psychosocial intervention.

The topic of this study was to evaluate state-dependent effects of diazepam on the frequency characteristics of 47-channel spontaneous EEG maps. A novel method, the FFT-Dipole-Approximation (Lehmann and Michel, 1990), was used to study effects on the strength and the topography of the maps in the different frequency bands. Map topography was characterized by the 3-dimensional location of the equivalent dipole source and map strength was defined as the spatial standard deviation (the Global Field Power) of the maps of each frequency point. The Global Field Power can be considered as a measure of the amount of energy produced by the system, while the source location gives an estimate of the center of gravity of all sources in the brain that were active at a certain frequency. State-dependency was studied by evaluating the drug effects before and after a continuous performance task of 25 min duration. Clear interactions between drug (diazepam vs. placebo) and time after drug intake (before and after the task) were found, especially in the inferior-superior location of the dipole sources. It supports the hypothesis that diazepam, like other drugs, has different effects on brain functions depending on the momentary functional state of the brain. In addition to the drug effects, clearly different source locations and Global Field Power were found for the different frequency bands, replicating earlier reports (Michel et al., 1992).

We review the controlled trials of antidepressant treatment in methadone patients. Several studies show antidepressant effects, but none demonstrate clear improvement in drug abuse. This is contrary to "self-medication" but rather suggests depression is either independent or substance induced. Methodologic limitations are noted, especially reliance on cross-sectional mood assessment, which may select transient mood disturbances rather than true affective disorder. We review our previously published pilot study of imipramine in depressed methadone patients selected by lifetime history, and we report four year treatment course in the nine patients who responded favorably during that trial. Patients remained euthymic during imipramine treatment and relapsed to depression during attempts to taper it. This suggests imipramine had an enduring antidepressant effect. However, intermittent drug use remained a problem for several patients, suggesting depression and drug abuse are at least in part independent disorders. Placebo controlled replications, combinations of antidepressant medication with psychosocial interventions, and exploration of antidepressants as adjuncts in methadone detoxification, are suggested avenues for further research.

Map landscape-based segmentation of the sequences of momentary potential distribution maps (42-channel recordings) into brain microstates during spontaneous brain activity was used to study brain electric field spatial effects of single doses of piracetam (2.9, 4.8, and 9.6 g Nootropil UCB and placebo) in a double-blind study of five normal young volunteers. Four 15-second epochs were analyzed from each subject and drug condition. The most prominent class of microstates (covering 49% of the time) consisted of potential maps with a generally anterior-posterior field orientation. The map orientation of this microstate class showed an increasing clockwise deviation from the placebo condition with increasing drug doses (Fisher's probability product, p < 0.014). The results of this study suggest the use of microstate segmentation analysis for the assessment of central effects of medication in spontaneous multi-channel electroencephalographic data, as a complementary approach to frequency-domain analysis.

We describe 2 patients with clinical syndromes suggestive of Wegener's granulomatosis: elevated titers of cytoplasmic antineutrophil cytoplasmic antibodies (cANCA), bronchocentric granulomatosis, and acute renal failure. A renal biopsy in one case showed crescentic glomerulonephritis and in the other case showed interstitial nephritis. These cases may reflect bronchocentric granulomatosis among a spectrum of diseases associated with cANCA. Use of cANCA may identify those patients with bronchocentric granulomatosis who require immunosuppressive therapy.

The purpose of this article is to present the fourth case report of bilateral discoid medial menisci. A previously unreported anomaly of the tibial plateaus associated with the discoid menisci was also present bilaterally. The patient was treated successfully by excision of the central anomalous discoid portion of the menisci, using arthroscopic techniques.

Corynebacterium group D2 is a gram-positive bacillus easily identified in clinical microbiology laboratories. However, this organism is often disregarded as a skin and mucous contaminant. The Spanish literature has recently described Corynebacterium group D2 as a urinary pathogen in a specific patient population. We report a case of Corynebacterium group D2 infection to illustrate the potential pathogenicity and clinical presentation of infection due to this organism in the United States.

Revision total hip replacement has traditionally required a trochanteric osteotomy for successful cement removal and component reinsertion. In this study the authors have concluded that in most instances the revision total hip replacement procedure can be successfully performed without trochanteric osteotomy. The advantages are underscored by the high percentage of trochanteric complications with trochanteric osteotomy for revision total hip replacement and the ease of rehabilitation without trochanteric osteotomy. Also, improved functional results without trochanteric osteotomy were noted. The specific indications for the procedure included revision total hip replacement with ununited prior trochanteric osteotomy, revision total hip replacement with femoral shaft fractures, and revision total hip replacement with stem fractures requiring only acetabular revision. The contraindications to the procedure are fibrous union or ununited trochanteric osteotomy from prior total hip replacement, severe acetabular protrusion of the acetabular component, advanced myositis ossificans, ankylosis of the hip, and advanced proximal femoral osteoporosis. The operating room records, x-rays, and outpatient records of 63 total hip revisions in 52 patients were reviewed. There was a minimum 2-year follow up with a range from two years to seven years. The patients were divided into two groups, comparing 21 trochanteric osteotomized revisions to 44 with trochanteric sparing techniques. Both groups were analyzed for age, type of implant, intraoperative perforation of femur, intraoperative femoral shaft fractures, intraoperative cortical window, component malpositioning extraneous cement, intraoperative blood loss, operating time, postoperative leg length inequality, persistent abductor weakness, average first day of ambulation, wound infection, dislocation, nonunion of the trochanter, and postoperative pain. In the nonosteotomized group, there was a 21% decreased blood loss, a 14% decrease in persistent abductor weakness, a 14% decrease in subluxation and dislocation, a 30% decrease operating time and a 50% reduction in intraoperative femoral perforation. In the osteotomized group there were six cases of fibrous union of the greater trochanter, two cases requiring removal of broken wires for trochanteric bursitis. A detailed surgical technique and representative cases are presented. In carefully selected cases, revision total hip replacement is optimally performed without trochanteric osteotomy. Postoperative trochanteric problems of nonunion, broken wires, bursitis, and abductor weakness can effectively be eliminated by avoiding trochanteric osteotomy.(ABSTRACT TRUNCATED AT 400 WORDS)