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U Hegerl

Publications and source records attributed to U Hegerl.

120 records · Page 7Linked to original sources
PubMed1988

Auditory evoked potentials as possible predictors of outcome in schizophrenic outpatients.

As part of a follow-up study on long-term neuroleptic treatment, 36 schizophrenic out-patients under neuroleptic treatment were studied in an 'auditory oddball' event-related potential paradigm after a 3-month stabilization phase following clinical discharge. In the first cross-sectional analysis, we evaluated the influences of age and gender and tried to find auditory evoked potential (AEP) variables, which might be promising as potential predictors of the course of illness. Compared with healthy age-matched controls, the patients showed smaller N1/P3-amplitudes. Males and females showed only minor AEP-differences, the amplitude N1/P2 being slightly higher in females. Age correlated positively with the latency P3 and negatively with the latency P2R. The interpeak latency P3-P2R showed the highest correlation with age. Test/re-test reliability was measured and variables with r less than 0.60 were rejected. The amplitudes N1/P2 and N1/P3 showed the highest test/re-test correlations. The more severely disturbed patients (global assessment scale [GAS]-score less than 65) had shorter interpeak latencies P2F-N1F than the less disturbed patients (GAS greater than or equal to 65). Patients with a high rate of relapse tended to have shorter interpeak latencies P2F-N1F than patients with low rates of relapse. Our results indicate that the interpeak latency P2F-N1F has an acceptable test/re-test reliability (C3: r = 0.72; C4: r = 0.80) and is related to clinical variables characterizing the course and outcome of illness. This leads to the hypothesis that a short interpeak latency, P2F-N1F, might be a predictor of poor prognosis.

Adult↗
PubMed1988

Detection of brainstem lesions in multiple sclerosis: comparison of brainstem auditory evoked potentials with nuclear magnetic resonance imaging.

Topographical information provided by brainstem auditory evoked potentials (BAEPs) was investigated in 43 patients by comparison with cerebral nuclear magnetic resonance imaging (NMR). Lesions in the region of the brainstem auditory pathways were demonstrated by BAEPs in 44.2%, and in 39.5% by NMR. As regards brainstem levels, in 15/21 (71.4%) with abnormal findings at least one lesion was verified by NMR-matched BAEP results. The study confirms the topographical information provided by the BAEPs on the different levels of the brainstem, but not the assumption that generation of the BAEPs is predominantly ipsilateral. BAEPs retain their importance for the detection of disseminated lesions in the diagnosis of multiple sclerosis (MS) in the era of expensive imaging methods.

Adolescent↗
PubMed1987

Auditory evoked potentials and response to lithium prophylaxis.

Auditory evoked potentials were recorded in 28 euthymic patients with affective psychosis who had received lithium prophylaxis for at least 5 years. Binaural clicks at 4 intensities were presented in randomized order via headphones. Potentials were recorded from Cz, C3, and C4 referenced to linked mastoid electrodes. N1-P2 amplitudes, N1 and P2 latencies, and the slope of the amplitude/stimulus intensity function (ASF) were determined in each patient. The patients were divided into responders and nonresponders on the basis of whether or not they had been hospitalized for treatment of relapses during the last 5 years of lithium prophylaxis. The ASF was steeper for all leads in responders than in nonresponders. In addition, N1 latencies were shorter for all leads in responders than in nonresponders. Age played a role in the differences observed between responders and nonresponders for ASF, but not for N1 latencies.

Adult↗
PubMed1986

Diagnostics of extra-cranial carotid stenoses. Comparison of CW-Doppler sonography and intravenous digital subtraction angiography.

In 98 internal carotid arteries, continuous-wave ultrasound Doppler sonography (USD) and i.v. digital subtraction angiography (DSA) of the internal carotid arteries were performed. The findings were compared with each other prospectively and on the basis of conventional angiography findings. The aim of this investigation was to clarify, whether DSA would show stenoses with lumen restriction of less than 50% more precisely than USD, or whether it would enable clearer localization of any vascular lesions. The results revealed that in cases of haemodynamic effective stenoses and occlusions both procedures correlated well with each other and also with catheter angiography. However, USD and DSA showed increasing discrepancies of findings with decreasing degree of severity of the stenosis. The accuracy for localization of stenoses also decreased markedly for both methods with increasing distance from the carotid bifurcation. In the case of congruent findings of USD and DSA in haemodynamic effective stenoses (degree of stenosis more than 75%) or occlusions conventional angiography did not increase the diagnostic information, and it seems therefore dispensable for vascular surgical decisions. However, in cases with existing clinical symptoms with contradictory or negative USD and DSA findings angiography is still indicated.

Adult↗
PubMed1985

[EEG findings in patients with aortocoronary bypass--a visual-morphologic analysis in comparison with clinical data].

In course of a catamnesis during a period of 1,5 up to 5 years after operation we made electroencephalographic examinations in 140 patients submitted to an aorto-coronary-veins-bypass (ACVB). Compared with a control group of corresponding age we observed a significant frequency of focal disturbances, being interpreted as expression of an increased functional lability due to vascular effects. 14 percent of these patients showed evident signs of cerebrovascular insufficiency. 33 percent suffered from symptoms of the unspecific pseudoneurasthenic syndrome, often to be found in the preliminary region of cerebrovascular insufficiency. Compared with the control group we found among the EEG of alpha-type within the ACVB-group a significantly increased number of subvigilant patterns. There were no relations between the extent of these patterns and the clinical syndromes of cerebrovascular insufficiency and pseudoneurasthenia. The increased appearance of fluctuations of vigilance within the group showing a higher vascular morbidity can be regarded as a first step of limited regulative dynamics. The results of this study confirm the necessity of an interdisciplinary medical treatment of patients suffering from arteriosclerosis.

Adult↗
PubMed1985

[Late acoustically evoked potentials--effect of age, sex and different study conditions].

54 healthy volunteers (25-82 years) were studied in an "auditory oddball" event-related potential paradigm. The tones (80%, 800 Hz; 20%, 1,600 Hz) were presented via two earphones in an randomized form. The rare tones were counted by the volunteers. Each volunteer was tested with the conditions, "eyes open" and "eyes closed". We found: An increase of the P3-latency of 0.92 ms/year (280 ms in the age of 20 years), and a decrease of P3-amplitude of 0.14 microV/year (17.2 microV in the age of 20 years). In contrast to other studies, the amplitude of the P2-wave (12.8 ms in the age of 20 years) and the latency of the P2-wave (160 ms in the age of 20 years) was not influenced by age. Females showed greater amplitudes of the P2- and P3-components. Females showed a clearly smaller increase on P3-latency with age (0.25 ms/year, starting with 296 ms in the age of 20 years) than males (1.3 ms/year, starting with 272 ms in the age of 20 years). The condition "eyes open" or "eyes closed" did not influence the late auditory evoked potentials. The results were interpreted by taking into account the great sensitivity of the late evoked potentials for changes of the state, which can be defined as well on the neurophysiological level as on the behavioural level.

Acoustic Stimulation↗
PubMedDate not supplied

[Programmes against depression].

BACKGROUND: Depressive disorders represent a major public health concern, regarding their high frequency and their important cost. Depression impair the quality of life more than any other disease, sometimes leading to suicidal ideas or behavior. Indeed, 50% of patients with severe major depression commit suicide. Numerous studies showed that depressive disorders are frequently not recognised, and regularly untreated. In France, where at least 3 millions of inhabitants are concerned, 38% of depressed patients are not using any health system. When they are asking for care, the majority of depressed patients visit their general practitioner (51%), whereas less than 10% visit a psychiatrist. Even when the diagnostic is correct, the treatment prescribed is not systematically relevant. The treatment is, for example, frequently proposed for a too short period, and sometimes the prescribed product does not have proven antidepressive efficacy. Furthermore, as incorrect informations are frequently given to patients, and as there is a general biased judgement about psychotropic drugs in the general population, the compliance is usually poor for antidepressive treatment. Therefore, only a small minority of depressed patients benefits from an adequate care. Public health information methodological asserts. To improve this situation, delivering simple and clear-cut recommendations cannot be considered as sufficiently effective, and public health interventions are required. Different programs improving the recognition of depressive disorders have already been tested in some countries with encouraging results. These programs are based on information campaigns given to the public, and the training of general practitioners about the management of depressive disorders. The "Defeat Depression" campaign in Great-Britain and the "National Depression Screening Day" in the United-States of America may represent informative examples. Restricting these programs to general practitioners only is frequently criticized, as this may reduce efficacy. A multilevel approach is crucial for the success of action programmes against depression, because synergistic effects can be expected. In Germany, the "Nürnberger Bündnis gegen Depression" project was based on four levels, and effectively reduced the suicide rate. These levels of action included "cooperation with GPs", such as training sessions based on video, and presence of a phone hotline, "public relations activities", "training sessions for multipliers", such as priests, social workers and media, and "special offers for high risk groups and self-help activities". In France, such a program is clearly required.

Antidepressive Agents↗
PubMedDate not supplied

Superior temporal gyrus and P300 in schizophrenia: a combined ERP/structural magnetic resonance imaging investigation.

Decrement of the auditory P300 component of the event-related potentials (ERP) is a robust finding in schizophrenic patients and seems to be most pronounced in the left temporal region. Structural MRI studies support the hypothesis that regional structural brain differences in this patient group include reduced volume in temporal lobe structures. The aim of the presented study was to investigate the possible gray matter volume reductions in the left posterior superior temporal gyrus (STG) and the P300 reduction and left <right topographic asymmetry in schizophrenic patients. Therefore, in 50 male schizophrenic patients and 50 age- and educational level-matched male controls, auditory ERPs and structural MRI measurements of the gray matter volume of the STG were assessed. In the group of patients, the psychopathological symptom of thought disorder was correlated with the electrode site T3 and underlying gray matter of the left posterior superior temporal gyrus. The subgroup of patients with pronounced negative symptoms was analyzed with respect to ERP and structural MRI measurements. Our data revealed no evidence for a reduction of P300 amplitude or left STG gray matter volume in schizophrenic patients. However, the higher amount of thought disorders was related to a small T3 amplitude. No associations between the electrophysiological and structural measurements could be detected. There were also no significant reductions of ERP and MRI measurements within the subgroup of patients with pronounced negative symptoms.

Adult↗