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Fanelsa A, Schellenberg R, Hillebrecht FU, Kisker E, Menchero JG, Kaduwela AP, Fadley CS. Magnetic dichroism in core-level x-ray photoemission with unpolarized excitation. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:17962-17965. [PMID: 9985931 DOI: 10.1103/physrevb.54.17962] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Dimpfel W, Hofmann HC, Prohaska A, Schober F, Schellenberg R. Source density analysis of functional topographical EEG: monitoring of cognitive drug action. Eur J Med Res 1996; 1:283-90. [PMID: 9367941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Electrical changes of the brain induced by mental work in the presence or absence of a drug formulation containing dimethylaminoethanolorotrate (DMAE), vitamins and minerals were analysed. Sixty elderly volunteers (30 females and 30 males; aged 40 - 65) who lacked concentration and efficiency during mental exercise according to their own opinions participated in a double-blind, placebo-controlled study. The EEG recordings were carried out before and after 12 weeks medication and were analysed according to the electrical charges at the scalp surface (Laplacian estimate) followed by Fast Fourier Transformation to obtain quantitative data. Whereas no change of electrical charge could be observed after 12 weeks of treatment in the placebo group, the verum group taking 1 capsule per day of an established drug containing a biogenic amine-vitamin combination revealed decreases in theta power during rest and increases in absolute theta power induced by mental demand within the area known to change its electrical activity during mental exercise. In the light of the current hypothesis that high theta resting power and low increases at frontotemporal brain areas during mental work indicate mental impairment, treatment with the drug under investigation was seen to successfully reverse these changes. This drug effect was localized in the frontotemporal cortex in a statistically significant manner during both the memory and the symbol recognition tests. The observed effect is fully consistent with a previous study using Fourier transformed data from conventional EEG voltage recordings. It can be concluded that an analysis of EEG data by means of the charge mode provides an excellent tool to quantify drug effects especially in cognitive research. A second perspective arises from the fact that it should be possible to recognize mental impairments at a very early stage by using this method, thus providing the possibility of an early treatment.
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Gerber WD, Schellenberg R, Thom M, Haufe C, Bölsche F, Wedekind W, Niederberger U, Soyka D. Cyclandelate versus propranolol in the prophylaxis of migraine--a double-blind placebo-controlled study. FUNCTIONAL NEUROLOGY 1995; 10:27-35. [PMID: 7649498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The aim of the present study was to ascertain the comparative efficacy of cyclandelate, a migraine prophylactic with calcium overload blocking properties, versus propranolol, a non-selective beta-adrenergic blocker, and placebo. Based on different statistical analysis procedures (including time series analysis) a responder and nonresponder evaluation for cyclandelate and propranolol was performed. In addition, an attempt was made to identify the dose relationship of the various drugs on headache parameters. In a double-blind placebo-controlled study 84 patients were treated in a placebo run-in phase (4 weeks). The patients were then randomized by the statistical criterion of placebo responder and nonresponder to either the cyclandelate or the propranolol group. The total treatment period included a low-dosage phase (8 weeks) and high-dosage phase (8 weeks). All patients kept a headache diary before, during and after treatment. The data were assessed by time series analysis (ARIMA), as well as by analysis of variance and nonparametric statistics. Based on ARIMA statistics, 39.3% of the patients showed a significant improvement of migraine during treatment with cyclandelate compared with 29.4% placed on propranolol. Higher doses of cyclandelate and propranolol were more effective. Using the qualitative response-criterion of a 50% reduction in migraine symptoms, cyclandelate showed a response in 67.9% and propranolol in 41.2% of all cases. It can therefore be concluded that cyclandelate as well as propranolol are two comparable substances in the prophylactic treatment of migraine, with cyclandelate showing fewer side effects.
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Schellenberg R, Todorova A, Dimpfel W, Schober F. Pathophysiology and psychopharmacology of dementia--a new study design. I. Diagnosis comprising subjective and objective criteria. Neuropsychobiology 1995; 32:81-97. [PMID: 7477806 DOI: 10.1159/000119219] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In a double-blind placebo-controlled psychopharmacological study 263 patients with cognitive impairment were screened and 137 of them were selected (following defined inclusion and exclusion criteria) to participate in a clinical trial (for results of treatment phase see part II, in preparation). The pretreatment state was evaluated twice using quantitative-topological EEG (qEEG) and psychopathological rating scales. There is a significant correlation between total score values of nearly all dementia-specific neuropsychological rating scales and absolute spectral power in the lower frequency ranges (delta, theta, alpha 1) at rest. In order to increase the diagnostic power, qEEG was recorded simultaneously with the performance in four different psychometric tests. It was found that the worse the psychopathological rating of a patient, the higher the absolute theta power at rest and the smaller the test- and demand-dependent further increase in theta power. The percentage of task-induced power increase in delta and theta frequency range appeared to be an efficient indicator for a reliable discrimination between healthy elderly individuals and demented patients (rank correlation coefficient for theta in F7: r = +0.55), which will also serve for evaluation of treatment.
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Schober F, Schellenberg R, Dimpfel W. Reflection of mental exercise in the dynamic quantitative topographical EEG. Neuropsychobiology 1995; 31:98-112. [PMID: 7760991 DOI: 10.1159/000119179] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The aim of this study was to investigate the activation process of the central nervous system during mental demand in a complex psychophysiological situation. A 17-channel quantitative topographical EEG was recorded in 48 healthy volunteers (male and female, aged 49 +/- 6 years), using the CATEEM system, during four different psychometric tests (simple reaction time measurement, concentration performance, figure detection and word recall test). The mental load varied with each test, producing a graduated increase in spectral power density in delta and theta frequency range on the EEG in the fronto-temporal, parietal and occipital regions of the cortex and a generalized decrease in alpha power. During the rest periods after each test a graduated increase in alpha 1 power was seen as a possible expression of change in vigilance level. With this method we were able to differentiate two effects of psychometric tests on brain activity: the actual mental demand itself and the influence on the vigilance level.
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Schober F, Schellenberg R, Dimpfel W. [A new method for assessment of mental performance during simultaneous, quantitative, topographical electroencephalometry and psychometry in pharmacology. Proof of the effect of a combination of biogenic amines, vitamins, minerals and trace elements]. ARZNEIMITTEL-FORSCHUNG 1994; 44:1285-95. [PMID: 7848346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Assessment of the Mental Performance during Simultaneous Quantitative Topographical Electroencephalometry and Psychometry in Pharmacology/Proof of influence of a biogenic amine-vitamin combination. The aim of this study was to verify the effect of a combination medicine (Vita-Gerin-Geistlich) on the human EEG pattern during psychometric (cognitive) tests given to 43 patients with poor concentration and thinking problems. A randomised, parallel, placebo-controlled double-blind study was performed. Applying 17-channel quantitative electroencephalometry and psychometric tests simultaneously this study revealed a test-dependent increase in absolute spectral EEG power in the delta and theta frequency bands, mainly observed in the frontotemporal cortex. After 8 weeks the increase in EEG power differed significantly with respect to taking placebo and verum (1 capsule/day). Verum caused a stronger rise in spectral delta and theta power, the psychometric test performance also improved. Both effects could be verified statistically. The novel EEG-controlled psychometric test set (enabling artefact-free EEG recording during psychometric tests) which was developed and used in this study represents a valid tool for future pharmacological research.
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Schellenberg R, Milch W, Schwarz A, Schober F, Dimpfel W. Quantitative EEG and BPRS data following Haldol-Decanoate administration in schizophrenics. Int Clin Psychopharmacol 1994; 9:17-24. [PMID: 7910833 DOI: 10.1097/00004850-199400910-00003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Approximately one-third of schizophrenic patients receiving antipsychotic drugs obtain little or no benefit from them. In some reports, response has been linked with "prognostic" factors, including abnormal EEG and drug response (pharmaco-EEG). Measurements of topological EEG spectral power and Brief Psychiatric Rating Scale (BPRS) values were obtained in 15 schizophrenics over a period of 20 min immediately after the first application, and at weekly intervals after single intramuscular injection of 2 ml depot haloperidol (Haldol-Decanoate). A highly significant increase in the alpha-1 power density at almost all positions and an increase in theta power at parietotemporal regions can be described as electrophysiological parameters of the acute pharmaco-EEG. BPRS values decreased continuously within the first 2 weeks followed by an increase to the predrug level after the fourth week. Over the whole observation period there was a correlation between neurophysiological data (alpha-1 power) and clinical symptomatology (BPRS total score; r = -0.7). Therefore, it can be concluded that quantitative EEG recordings are able to serve as a tool for the optimization of the depot neuroleptic treatment in schizophrenics.
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Salari H, Bramley A, Langlands J, Howard S, Chan-Yeung M, Chan H, Schellenberg R. Effect of phospholipase C inhibitor U-73122 on antigen-induced airway smooth muscle contraction in guinea pigs. Am J Respir Cell Mol Biol 1993; 9:405-10. [PMID: 8398179 DOI: 10.1165/ajrcmb/9.4.405] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The importance of phospholipase C (PLC) in airway smooth muscle contraction was studied, using an inhibitor of PLC, 1-[6-[[17 beta-3-methoxyestra-1,3,5(10)-trien-17-yl] amino]hexyl]-1H-pyrrole-2,5-dione (U-73122). Tracheas from ovalbumin (OA)-sensitized guinea pigs contracted rapidly after exposure to low concentrations of antigen (OA). However, tracheas treated with U-73122 for 10 min prior to the addition of antigen, demonstrated a 3 log rightward shift in the OA dose-response curve with an IC50 of 7 microM. The analogue of U-73122, 1-[6[[17 beta-3-methoxyestra-1,3,5 trien-17-yl]amino]hexyl]-2,5-pyrrolidine-dione (U-73433), was approximately 5-fold less active in inhibiting smooth muscle contraction. In addition to the inhibition of antigen-induced smooth muscle contraction, U-73122 inhibited carbachol- and leukotriene D4-induced smooth muscle contraction. Furthermore, U-73122 inhibited in a dose-dependent manner antigen-induced histamine release from guinea pig tracheal tissue. The inhibition of smooth muscle contraction by U-73122 correlated well with the inhibition of polyphosphoinositide mediates smooth muscle contractile responses to muscarinic agonists and leukotrienes as well as antigenic-induced contraction.
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Schellenberg R, Schwarz A. EEG- and EP-mapping--possible indicators for disturbed information processing in schizophrenia? Prog Neuropsychopharmacol Biol Psychiatry 1993; 17:595-607. [PMID: 8103234 DOI: 10.1016/0278-5846(93)90008-g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. Schizophrenic patients have been investigated electroencephalographically to describe disturbed information processing mechanisms. 2. 16-channel quantitative EEG and P300 were recorded at resting conditions before and during neuroleptic depot injection. 3. Reduced occipital alpha-power and alpha-power dependent P300-amplitudes were found in the schizophrenics. 4. Hippocampal structures are involved in the disturbed information processing mechanisms.
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Miyata M, Schuster B, Schellenberg R. Sulfite-containing Canadian pharmaceutical products available in 1991. CMAJ 1992; 147:1333-8. [PMID: 1483237 PMCID: PMC1336441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
OBJECTIVE To compile an inclusive list of Canadian pharmaceutical products available in 1991 that contained sulfites. DATA SOURCES Written and oral responses from 94 pharmaceutical companies selected from the 1989 Compendium of Pharmaceuticals and Specialties. RESULTS A list of sulfite-containing pharmaceutical products was compiled from data supplied by the 90 responding companies. Companies whose products contained no sulfites were separately identified. CONCLUSIONS Sulfites are present in many pharmaceutical products and are one of many excipients and additives that have been reported to cause severe adverse reactions. The provided list should be a useful aid for health care practitioners when prescribing pharmaceutical products for sulfite-sensitive patients.
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Schellenberg R, Schwarz A, Knorr W, Haufe C. EEG-brain mapping. A method to optimize therapy in schizophrenics using absolute power and center frequency values. Schizophr Res 1992; 8:21-9. [PMID: 1358183 DOI: 10.1016/0920-9964(92)90057-c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In this study EEG-spectral parameters like mean alpha-power values and center frequency values are computed as maps and compared using significant probability mapping. The parameters are used to describe changes of the functional state of the brain after neuroleptic depot injection (Haldol-Decanoate) in schizophrenic patients. The absolute alpha-power increased significantly (p < 0.01), especially within the first week after injection mostly in the left hemispheric regions. The center frequency decreased most significantly (p < 0.02) between the first and second week after haldol depot injection at the right occipital regions. Both parameters are efficient to describe functional changes correlated with clinical symptomatology, even 3-5 days earlier. Thus, EEG power and center frequency mapping can be used very efficiently to estimate the optimal time between sequential neuroleptic depot injections.
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Boulay J, Schellenberg R, Brady PG. Role of ERCP and therapeutic biliary endoscopy in association with laparoscopic cholecystectomy. Am J Gastroenterol 1992; 87:837-42. [PMID: 1535478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Laparoscopic removal is rapidly becoming the preferred method of cholecystectomy; however, choledocholithiasis cannot usually be managed with a laparoscopic approach. Combined endoscopic sphincterotomy and laparoscopic cholecystectomy is a potential solution to this problem. To determine the feasibility of this combined procedure we studied 41 patients who had both endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic cholecystectomy. Indications for ERCP included jaundice, gallstone pancreatitis, dilated ducts on sonography, elevated liver enzymes, or stones seen on operative cholangiography. Twenty-eight patients had ERCP preoperatively. Nine patients had common duct stones; these were successfully removed from eight patients after sphincterotomy. Two patients had unexpected strictures requiring a change in surgical approach. Thirteen patients had ERCP postoperatively. Eight of those patients had common duct stones, and all were successfully removed following endoscopic sphincterotomy. Three patients had postoperative strictures, one of which was treated by endoscopic stent placement. No complications as a result of ERCP or sphincterotomy were encountered. ERCP and endoscopic sphincterotomy can be safely performed both preoperatively and as early as 1 day postoperatively. If indicators of choledocholithiasis are present, preoperative ERCP is preferred, because stone removal occasionally is unsuccessful, and cholangiographic findings may change the operative approach. Postoperative ERCP can define and, in some instances, treat biliary tract injuries resulting from laparoscopic cholecystectomy.
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Siewert B, Schellenberg R, Knorr W, Kropf S, Beyer H, Schindler M, Schwarz A. [Left hemispheric site of EEG findings in patients with schizophrenic psychoses]. FORTSCHRITTE DER NEUROLOGIE-PSYCHIATRIE 1990; 58:455-9. [PMID: 2086430 DOI: 10.1055/s-2007-1001209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
It was the aim of our study to examine the interhemispherical and extrahemispherical integration that is possibly disturbed in patients suffering from schizophrenic psychoses, using an easy method of EEG performance spectral analysis. For this purpose, the EEG at rest and the functional EEG were determined in 69 schizophrenic patients (ICD) and 22 healthy subjects and the EEG reactivity was calculated. Differences especially in alpha-2 reactivity were seen both intrahemispherically and interhemispherically. This supports the concept of left hemispheric dysfunction in patients suffering from schizophrenic psychoses.
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Schellenberg R, Knorr W, Schindler M, Kropf S, Beyer H. EEG-power spectral components of schizoaffective disorders. Schizophr Res 1990; 3:357-9. [PMID: 2282342 DOI: 10.1016/0920-9964(90)90023-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Schellenberg R, Schwarz A, Knorr W, Schindler M. [EEG performance spectral mapping during drug therapy in a patient with schizophrenic psychosis]. PSYCHIATRIE, NEUROLOGIE, UND MEDIZINISCHE PSYCHOLOGIE 1990; 42:618-24. [PMID: 1981811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In a paranoid-hallucinatoric patient with chronic course and acute exacerbation a EEG mapping study during neuroleptic treatment was carried out. The typical changes of the alpha power spectra in schizophrenic psychoses as well the normalization after neuroleptic treatment could be found in the alpha map. The changes were in correlation to the clinical state.
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Schellenberg R, Bogerts B, Falkai P, Suhr H, Halbach M, Gruzelier JH. Nasopharyngeally and vertex recorded P300's in normal subjects. Int J Psychophysiol 1990; 9:201-4. [PMID: 2228755 DOI: 10.1016/0167-8760(90)90075-o] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The P300 waveform has been associated with cognitive activity during information processing, and the hippocampus has been discussed as a possible generator of this waveform. This being the case some would argue that it should be possible to record the P300 with a shorter latency and greater amplitude from an electrode placed as near the hippocampus as possible. Under local anaesthesia we inserted a specially constructed needle electrode through the left nostril in the recessus pharyngeus close to the hippocampus. The results did not support the hippocampal hypothesis. Nasopharyngeally recorded P300's were found to have significantly decreased amplitudes and extended latencies when compared to vertex recordings.
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Schellenberg R, Knorr W, Beyer H, Kropf S, Schindler M, Bölsche F, Belicke B, Kondratjuk G. Multivariate EEG power spectral analysis in acute schizophrenics. Int J Psychophysiol 1989; 8:85-91. [PMID: 2584086 DOI: 10.1016/0167-8760(89)90022-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The electroencephalogram (EEG) during information processing is influenced by specific changes in brain electrical activity. Based on the theory of disturbed information processing in schizophrenics, we analysed auditory stimulus induced EEG changes by Fast Fourier Transformation. The most important of the significant stimulation-dependent EEG power changes were measured in the 0.5-3.5 Hz and 10-13.5 Hz frequency bands in the left frontoparietal lead. In a multivariate analysis the separation of the subjects examined into acute schizophrenics and normals was incorrect in only 21% of the cases (resubstitution rate); using pi-method an error of 31% was estimated.
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Schellenberg R, Christoph B, Kluba J, Knorr W, Siewert B, Schindler M, Linsel A. Nasopharyngeal EEG recording in schizophrenic patients a preliminary remark. Int J Psychophysiol 1989. [DOI: 10.1016/0167-8760(89)90315-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Gruzelier J, Liddiard D, Dennis P, Schellenberg R. Validation of EEG topographical mapping with neuropsychological functional activation. Int J Psychophysiol 1989. [DOI: 10.1016/0167-8760(89)90165-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Schellenberg R, Zwiener U, Kühne GE. [Pathophysiologic aspects of schizophrenic psychoses--a review]. PSYCHIATRIE, NEUROLOGIE, UND MEDIZINISCHE PSYCHOLOGIE 1989; 41:193-9. [PMID: 2662232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The aim of research in the field of "Biological Psychiatry" is the phenomenological description of several aspects of psychiatric diseases and the exploration of their pathological mechanisms. The most used methods are biochemical, morphological, genetical, social psychiatric, neuro- and psychophysiological ones. From the pathophysiological view the most discussed hypothesis is that of a disturbed central information processing. In this paper a short introduction should be given on psychosocial influence on the development of psychotic symptomatology and on the periphere vegetative and electroencephalographic parameters in psychiatric patients.
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Schellenberg R, Knorr W, Beyer H, Kropf S, Schindler M, Bölsche F, Kondratjuk G. Repeated acoustic stimulation of acute schizophrenic patients and the habituation of EEG power changes. Int J Psychophysiol 1989; 7:55-63. [PMID: 2925465 DOI: 10.1016/0167-8760(89)90031-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Habituation in psychiatric patients to repeated stimuli has typically been described in connection with the measurement of the skin conductance orienting response. Here EEG power spectra of acute schizophrenic patients and normals to 4 trials of an acoustic stimulation were examined for evidence of habituation. In response to stimulation the alpha EEG reactivity was less distinct in schizophrenics than in normals. This is in agreement with the theory of hypovariability or hyperstability of the EEG in schizophrenics. Signs of habituation in acute schizophrenics were clearer in fast beta frequencies of the parietal leads.
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Schellenberg R, Knorr W, Beyer H, Kropf S, Schindler M, Bölsche F. [Multivariate discriminant analysis of EEG power spectra in acute schizophrenic patients and healthy probands]. PSYCHIATRIE, NEUROLOGIE, UND MEDIZINISCHE PSYCHOLOGIE 1988; 40:555-63. [PMID: 3237884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The electroencephalogram (EEG) during information processing is influenced by specific changes in brain electrical activity. Based on the theory of a disturbed information processing in schizophrenics we analysed auditory stimulus induced EEG changes by Fast Fourier Transformation. The most important of the significant stimulation dependent EEG power changes were measured in the 0.5-3.5 Hz and 10-13.5 Hz frequency bands in the left parietal lead. In a multivariate analysis the separation of the subjects examined into acute schizophrenics and normals was incorrect in only 21% of the cases (resubstitution rate): using the pi-method an error of 31% was estimated.
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Schuart J, Blume M, Schellenberg R. [Studies on the extraction of biologically active vasopressin from plasma (author's transl)]. DIE PHARMAZIE 1981; 36:353-5. [PMID: 7267684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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49
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Schellenberg R. Sicherheitstechnische Bauteilbegutachtung. VonK . H . Ringelstein,S. Dittmar,P. M??ller,P. Hofst�tter,B. Goritzke,H . Kerkhoff undD. Schlegel. Verlag T�V Rheinland GmbH, K�ln 1975. 1. Aufl., 122 S., zahlr. Abb. u. Tab., kart. DM 27,-. CHEM-ING-TECH 1976. [DOI: 10.1002/cite.330480521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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50
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Schellenberg R, Mielenz H. [Local treatment of bacterial infections in surgical ambulatory practice using Fucidine-gel]. ZEITSCHRIFT FUR ALLGEMEINMEDIZIN 1975; 51:1608-9. [PMID: 1210369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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