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U Hegerl

Publications and source records attributed to U Hegerl.

At least 19 recordsLinked to original sources
PubMed2003

Panic attacks, spike-wave activity, and limbic dysfunction. A case report.

INTRODUCTION: Several lines of evidence indicate that an increased neuronal excitability of the corpus amygdaloideum and hippocampus may be one pathophysiological condition of panic attacks. METHODS: In this report, we will describe the case of a 54-year-old female patient with a depressive syndrome who first experienced very rapid atypical panic attacks with dizziness, trance-like and distorted optical perception, but without clear epileptic symptoms. RESULTS: Several EEG recordings showed temporal sharp-waves and spike-wave patterns. Magnetic resonance imaging (MRI) revealed a hypodense area near left mesial temporal structures. Brain imaging with SPECT showed a hypoperfusion of the basal temporal cortical structures on the left side. Treatment with antidepressants had no effect, but the addition of valproic acid led to an attenuation of the panic attacks and epileptic potentials on the EEG. DISCUSSION: A clinical trial using anti-epileptics could be successful in patients not responding to antidepressants or in the presence of epileptiform EEG activity. In this article, we will review the literature concerning the complex relationship between panic attacks and ictal activity of limbic structures and discuss the difficult diagnostic classification of atypical cases.

Anticonvulsants↗
PubMed2003

Kinematic analysis of handwriting movements in patients with Alzheimer's disease, mild cognitive impairment, depression and healthy subjects.

A variety of studies have demonstrated that motor disorders, parkinsonism and extrapyramidal motor symptoms (EPMS) are common in patients with Alzheimer's disease (AD). Several studies have reported an association of EPMS with severity, progression and poor prognosis of AD. The majority of these studies used clinical assessments for the rating of EPMS. In this study, kinematic handwriting analysis was used to quantify differences in fine hand motor function in patients with probable AD and mild cognitive impairment (MCI, as an assumed initial stage of AD) compared to depressed patients and healthy controls. Both patients with MCI and patients with probable AD exhibited loss of fine motor performance. Movements of AD patients were significantly less regular than those of healthy controls.

Aged↗
PubMed2002

Methionine homozygosity at codon 129 in the prion protein is associated with white matter reduction and enlargement of CSF compartments in healthy volunteers and schizophrenic patients.

Twin studies point toward a substantial heritability in individual variations in the size of the human brain. However, the etiology is largely unknown. The prion protein (gene name: PRNP) aids cellular resistance to oxidative stress and neurodegeneration and is involved in neurodevelopment. This study examines the influence of a polymorphism in the PRNP gene on brain morphology in 47 healthy males and 43 male schizophrenic patients. All subjects underwent identical MRI scanning sessions followed by segmentation in cerebrospinal fluid (CSF), gray and white matter tissue, and genotyping for a biallelic polymorphism in PRNP (Met129Val). Genotype and allele frequencies did not differ between schizophrenic patients and controls but the polymorphism was associated with white matter tissue reduction (P = 0.024) and enlargement of CSF compartments (P = 0.039). These findings suggest that homozygosity for methionine at codon 129 is associated with decreased white matter tissue and larger CSF volume in right-handed male healthy volunteers and schizophrenic patients. This, however, being a novel finding, should warrant further investigation.

Adolescent↗
PubMed2002

[Knowledge and attitude of the general public regarding symptoms, etiology and possible treatments of depressive illnesses].

Within the German research network on depression, the Nuremberg Alliance against Depression aims at informing the public about depressive illness and preventing suicidality by carrying out a city-wide information campaign. Before the prevention program started, public attitudes and knowledge had been assessed in a public opinion survey in Nuremberg and in a control region. A total of 1426 randomly chosen inhabitants of Nuremberg and Würzburg completed a computer-assisted telephone interview during November and December 2000. They were asked about their knowledge and attitudes towards symptoms, causes, and treatment of depression. No relevant differences between Nuremberg and Würzburg were found. Depression is regarded as a serious illness. People seemed to be more knowledgeable as compared to the results of earlier surveys, but there are still important information deficits. This is especially true for males over 60, who show unfavorable attitudes. Eighty percent of the population consider antidepressants to be addictive, and 69% were convinced that the use of antidepressants would lead to personality changes. Future information campaigns should aim at describing depression as an often chronic disease similar to hypertonia or diabetes. Public knowledge about antidepressants must be improved.

Adult↗
PubMed2002

Cognitive-behavioural theories of helplessness/hopelessness: valid models of depression?

Helplessness and hopelessness are central aspects of cognitive-behavioural explanations for the development and persistence of depression. In this article a general overview concerning the evolution of those approaches to depression is provided. Included is a critical examination of the theories. The review of the literature suggests that those cognitive models describing helplessness/hopelessness as trait factors mediating depression do not really have a strong empirical base. The majority of those studies had been conducted in healthy or only mildly depressed subjects. Thus, there seems to be little justification for broad generalisations beyond the populations studied. It seems that some of the reported studies have not tested the underlying theories adequately (e. g. correlation had sometimes been interpreted as causation; adequate prospective longitudinal study designs had seldom been applied). Moreover, the theoretical models are not generally prepared to explain all depressive features (e. g. the possibility of a spontaneous shift in a manic episode). Despite those limitations, there is a relevant impact of the learned helplessness paradigm on preclinical research in neurobiological correlates of depressive states. Last but not least, the models are of high interest with respect to the theoretical background of important modules of cognitive-behavioural therapy and its acute and prophylactic effects.

Brain↗
PubMed2002

[The Werther effect. Significance, mechanisms, consequences].

The Werther effect is a highly regarded phenomenon in media effect research. Since the trail-blazing studies conducted by the American sociologist Phillips, there have been a great many attempts to quantify and evaluate imitative deeds that follow genuine suicides and apparent attempts at suicide. This paper starts by tracing the milestones along the way of research into the Werther effect. The concrete imitation patterns following suicides are then discussed, and the implications for responsible journalistic reporting that arise out of them are presented. This seems to be necessary, since despite many-sided and detailed findings on the Werther effect in Germany, there have so far been no experiments devoted to ways of exploiting these research results practically in a suicide prevention programme. Whilst in other countries preliminary guidelines for journalistic reporting have already been elaborated and in some countries even implemented, such efforts are still only in the very early stages in Germany.

Germany↗
PubMed2002

Comparison between the analysis of the loudness dependency of the auditory N1/P2 component with LORETA and dipole source analysis in the prediction of treatment response to the selective serotonin reuptake inhibitor citalopram in major depression.

OBJECTIVES: The loudness dependency of the auditory evoked potentials (LDAEP) is used as an indicator of the central serotonergic system and predicts clinical response to serotonin agonists. So far, LDAEP has been typically investigated with dipole source analysis, because with this method the primary and secondary auditory cortex (with a high versus low serotonergic innervation) can be separated at least in parts. METHODS: We have developed a new analysis procedure that uses an MRI probabilistic map of the primary auditory cortex in Talairach space and analyzed the current density in this region of interest with low resolution electromagnetic tomography (LORETA). LORETA is a tomographic localization method that calculates the current density distribution in Talairach space. RESULTS: In a group of patients with major depression (n=15), this new method can predict the response to an selective serotonin reuptake inhibitor (citalopram) at least to the same degree than the traditional dipole source analysis method (P=0.019 vs. P=0.028). The correlation of the improvement in the Hamilton Scale is significant with the LORETA-LDAEP-values (0.56; P=0.031) but not with the dipole source analysis LDAEP-values (0.43; P=0.11). CONCLUSIONS: The new tomographic LDAEP analysis is a promising tool in the analysis of the central serotonergic system.

Adult↗
PubMed2002

Comparison of the amplitude/intensity function of the auditory evoked N1m and N1 components.

This study compared the intensity dependence of the auditory evoked N1 and N1m components in 10 healthy subjects. The evoked responses were recorded simultaneously at 33 channels for the auditory evoked potentials (AEP) and with a 37-channel magnetometer for the auditory evoked fields (AEF). They were satisfactorily modeled by a tangential and a radial dipole per hemisphere for the N1 component and a tangential dipole in the left hemisphere for the N1m component. The tangential dipoles showed different dipole characteristics. The amplitude of the AEP rose significantly with increasing stimulus intensity whereas the amplitudes of the AEF tended to plateau between the highest intensities. The magnetic dipole shifted to the surface of the skull with higher stimulus intensity whereas the electric tangential dipole moved to the center of the skull. The latencies decreased with increasing stimulus intensity.

Adult↗
PubMed2002

Simultaneous ERP and event-related fMRI: focus on the time course of brain activity in target detection.

The event-related P300 potential has been widely used in neurophysiological research. It is usually evoked with an oddball paradigm. One main reason for its broad application in neurophysiological research is the fact that in several brain/mental diseases, such as Alzheimer's disease or schizophrenia, attenuations of the P300 amplitude and latency have been described. However, a precise correlation of the scalp data to the underlying brain regions was not possible, as the correct localization of the generators of scalp-measured electroencephalogram (EEG) data was limited, due to the low spatial resolution of EEG-data. With the availability of modern imaging technologies, functional Magnetic Resonance Imaging (fMRI) in particular, the underlying brain activations could be detected using an oddball task. Although the spatial resolution of fMRI is excellent, the time resolution is restricted. For a comprehensive understanding of the brain activity underlying the P300 paradigm, we have used a combination of EEG and fMRI to get a precise localization and a high-time resolution of the underlying brain activity.

Acoustic Stimulation↗
PubMed2001

In-vivo analysis of the human planum temporale (PT): does the definition of PT borders influence the results with regard to cerebral asymmetry and correlation with handedness?

The aim of our study was to examine whether the degree of planum temporale (PT) asymmetry and the possible correlation of morphological PT asymmetries with handedness are influenced by the definition of PT borders. For this reason, we applied three different anatomical PT definitions formerly used in the literature. The PT total (with the end of the Sylvian fissure (SF) as its posterior border) was separated into anterior and posterior regions. The border between anterior and posterior PT was set according to the following definitions: at the end of Heschl's gyrus (1st definition); at the start of the ascending SF ramus according to the 'knife-cut' method (2nd definition); and at the bifurcation of the SF (3rd definition). Thirty right-handed healthy men were recruited. MRI data sets analyzed with the software program BRAINS were used for in vivo PT volumetry. The Edinburgh Handedness Inventory (EHI) and the Hand Dominance Test were used to determine the degree of handedness. In summary, we detected that the type and the degree of asymmetry between left and right PT were strongly dependent on the definition used for PT borders: a left>right asymmetry was found in all PT regions, except a right>left asymmetry of the anterior PT according to our 1st PT definition (lateral to Heschl's gyrus) and a symmetry of the posterior PT according to our 3rd PT definition (posterior to SF bifurcation). In addition, a significant correlation was found between the degree of handedness measured by the EHI and the right posterior PT (3rd definition). We conclude that the influence of the definition of PT borders on the investigated variables may explain some of the variances between former investigations on PT asymmetry and handedness. The possible implications of the correlation between handedness and the extension of the right parietal PT are discussed and have to be elucidated by further studies.

Adolescent↗
PubMed2001

[Diagnosis and therapy of depression. Key role for the family physician].

Several epidemiological studies initiated by the World Health Organisation (WHO) have demonstrated the outstanding significance of depressive disorders in medical care and for public health aspects. Moreover it is evident that the majority of depressed patients is treated by primary care physicians, rather than by mental health specialists. Therefore, primary care physicians figure prominently in the diagnosis and treatment of depression. However, there is not always sufficient awareness of the fact that depression is among the most common and also with regard to suicidality among the most life-threatening diseases in the primary care setting. Clinical guidelines, taking into account the specific situation in primary care, should safeguard that depressive disorders are rapidly identified. As long as there are no complicating aspects, requiring the support of specialists, depression can usually be treated in primary care. Established standards for the treatment of depression would facilitate this task. Clinical guidelines for the primary care setting must be based on further clinical research.

Antidepressive Agents↗
PubMed2001

Corpus callosum and P300 in schizophrenia.

Functional abnormalities in the interhemispheric transfer via the corpus callosum in schizophrenia may result in filtering problems and information processing problems, which may in turn be related to the synchronization of cortical event-related activity. To explore whether a relationship exists between corpus callosum (CC) size, measured with in-vivo magnetic resonance imaging, and late auditory event-related P300 potentials, 50 patients with schizophrenia as well as 50 healthy controls were examined. The absolute CC size and subregional areas, as well as the CC areas adjusted for total brain volume, were not significantly different between patients with schizophrenia and controls. While no significant group differences were observed for P3a-, P3b-, PSW-amplitudes and P3b-latencies, P3a- and PSW-latencies were significantly prolonged for patients with schizophrenia. Absolute CC total size was significantly correlated with P3b-amplitudes in healthy controls (r=0.29; P=0.044). In patients with schizophrenia, significant correlations were observed between the subregion of the posterior body of the CC and positive slow wave (PSW; r=0.47; P=0.001). P3a-, P3b- and PSW-latencies were not significantly correlated to CC size in either patients with schizophrenia or healthy controls. The results are discussed in terms of the possibility that abnormalities in interhemispheric transfer may underlie the mechanisms of schizophrenia.

Adult↗
PubMed2001

[Evaluation of suicide prevention measures. Current state of research and resulting implications].

Even though the WHO recommended the implementation of regional and nationwide suicide-preventive activities, there is little evidence of their efficacy. The goal of this review is to discuss the different approaches concerning suicide prevention. On the one hand, strategies which try to improve the diagnosis and medical care of special high-risk groups are presented. On the other hand, population-based strategies are discussed. The main targets here are promoting public awareness, optimising primary care, restricting the presentation of suicides in mass media, and restricting the access to means for suicide. The combination of high-risk and population-based strategies might hold promise for the best effects.

Antipsychotic Agents↗
PubMed2001

P300 and symptom improvement in schizophrenia.

RATIONALE: A reduced amplitude of the auditory evoked P300 was interpreted as a trait marker of schizophrenia but reports about correlations between schizophrenic psychopathology and P300 amplitude indicate also a state character. OBJECTIVES: To shed light upon these trait and state aspects a longitudinal study was performed to investigate the influence of symptom improvement and atypical neuroleptics on the amplitudes of the P300 and their subcomponents. METHODS: P300 was recorded in 17 schizophrenic patients before and after 4 weeks under either clozapine or olanzapine in a double-blind controlled design. For comparison, 17 age- and sex-matched healthy subjects were investigated. Parietal and frontal P300 subcomponents were investigated separately using dipole source analysis. RESULTS: Schizophrenic patients had smaller parietal (temporo-basal dipole) but not frontal subcomponent amplitudes (temporo-superior dipole) than controls. For the whole sample subcomponent amplitudes did not change over 4 weeks despite clinical improvement but patients with a pronounced improvement of the PANSS positive score showed a slight enhancement of both subcomponents. This was not significant when the P300 amplitude was measured at a single electrode (Pz). No significant difference between clozapine and olanzapine concerning effects on P300 amplitudes were observed. CONCLUSIONS: The results indicate that P300 subcomponents are modulated by changes of positive but not by changes of negative symptoms or different neuroleptics. This result was obvious for P300 subcomponents but not for Pz electrode measurement, which may be due to a higher reliability of the dipole source activity. The results can be integrated into a hypothetical model containing two pathophysiological subgroups of schizophrenia.

Adult↗
PubMed2001

Assessment of handedness using a digitizing tablet: a new method.

The assessment of handedness is of interest in some psychiatric populations, above all in schizophrenic patients, because there may be a relationship between neurodevelopmental, hemispheric damage and psychiatric disease processes (Crow TJ. Schizophrenia Bulletin 1990;16:433-443; Tyler M, Diamond J, Lewis S. Schizophrenia Research 1995;18:37-41). Various methods to assess handedness have been proposed. In order to detect the most precise instrument for the assessment of handedness, two different measures, a questionnaire and a computational procedure for movement analysis, were compared in a group of healthy subjects. The ability of the methods to discriminate not only between the groups of right-handers (n=12) and left-handers (n=23), but also between left-handers trained in school to use the non-dominant right hand ('inconsistent' left-handers; n=11) and those allowed to use their left hand for writing ('consistent' left-handers; n=12) was investigated. For future investigations, our main concern was to determine if one method had superiority over the other. The results revealed that the Edinburgh Handedness Inventory (EHI) distinguishes just as well as the computational method between right-handers and non-right-handers. However, more precise discrimination between the subgroups of 'consistent' and 'inconsistent' left-handers is possible using digitized analysis of hand-motor performance. According to our results handedness should be assessed not only with the EHI, but also with the computer-aided analysis of hand-movements.

Adult↗
PubMed2001

Event-related potentials. Do they reflect central serotonergic neurotransmission and do they predict clinical response to serotonin agonists?

The increasing knowledge concerning anatomical structures and cellular processes underlying event-related potentials (ERP) as well as methodological advances in ERP data analysis (e.g. dipole source analysis) begin to bridge the gap between ERP and neurochemical aspects. Reliable indicators of the serotonin system are urgently needed because of its role in pathophysiology and as target of pharmacotherapeutic interventions in psychiatric disorders. Converging arguments from preclinical and clinical studies support the hypothesis that the loudness dependence of the auditory evoked N1/P2-response (LDAEP) is regulated by the level of central serotonergic neurotransmission. Dipole source analysis represents an important methodological advance in this context, because the two N1/P2-subcomponents, generated by the primary and secondary auditory cortex known to be differentially innervated by serotonergic fibers, can be separated. A pronounced LDAEP of primary auditory cortices is supposed to reflect low central serotonergic neurotransmission, and vice versa. LDAEP is a parameter with potential clinical value since subgroups of patients with a serotonergic dysfunction can be identified and can be treated more specifically. In depressed patients, a significant relationship between strong LDAEP, indicating low serotonergic function, and a favorable response to SSRI has been found. Additionally, there is evidence from several studies with patients with affective disorders implicating a strong LDAEP as a predictor of favorable response to a preventive lithium treatment.

Arousal↗