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1.
Transl Psychiatry ; 12(1): 268, 2022 07 07.
Article in English | MEDLINE | ID: mdl-35794104

ABSTRACT

Although the currently available antidepressants are well established in the treatment of the major depressive disorder (MDD), there is strong variability in the response of individual patients. Reliable predictors to guide treatment decisions before or in an early stage of treatment are needed. DNA-methylation has been proven a useful biomarker in different clinical conditions, but its importance for mechanisms of antidepressant response has not yet been determined. 80 MDD patients were selected out of >500 participants from the Early Medication Change (EMC) cohort with available genetic material based on their antidepressant response after four weeks and stratified into clear responders and age- and sex-matched non-responders (N = 40, each). Early improvement after two weeks was analyzed as a secondary outcome. DNA-methylation was determined using the Illumina EPIC BeadChip. Epigenome-wide association studies were performed and differentially methylated regions (DMRs) identified using the comb-p algorithm. Enrichment was tested for hallmark gene-sets and in genome-wide association studies of depression and antidepressant response. No epigenome-wide significant differentially methylated positions were found for treatment response or early improvement. Twenty DMRs were associated with response; the strongest in an enhancer region in SORBS2, which has been related to cardiovascular diseases and type II diabetes. Another DMR was located in CYP2C18, a gene previously linked to antidepressant response. Results pointed towards differential methylation in genes associated with cardiac function, neuroticism, and depression. Linking differential methylation to antidepressant treatment response is an emerging topic and represents a step towards personalized medicine, potentially facilitating the prediction of patients' response before treatment.


Subject(s)
Depressive Disorder, Major , Diabetes Mellitus, Type 2 , Antidepressive Agents/therapeutic use , DNA , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/genetics , Diabetes Mellitus, Type 2/genetics , Epigenesis, Genetic , Epigenome , Genome-Wide Association Study/methods , Humans
2.
Orthopade ; 48(11): 957-962, 2019 Nov.
Article in German | MEDLINE | ID: mdl-31559467

ABSTRACT

BACKGROUND: Rheumatic and mental disorders are common and affect each other. The comorbidities are often diagnosed too late or not at all but cause considerable suffering for those affected and have a negative effect on the health-related quality of life and therapeutic success. OBJECTIVES: Is there any evidence regarding common pathophysiological mechanisms and how can they be considered in terms of therapy? METHODS: Recent findings, reviews and basic literature are analyzed and an update is presented and discussed. RESULTS: The current data suggest a mutual influence of the factors stress and inflammation both in depressive disorders, anxiety disorders and chronic pain, as well as in diseases of the rheumatic type. There is a close relationship between immunological and neuronal processes that bi-directionally regulate the individual's stress response. CONCLUSIONS: For sufficient therapy the establishment of an interdisciplinary treatment concept in clinical everyday life is to be striven for. In addition to rheumatic treatment, this should include a multimodal approach to both pharmacological and psycho-socio-therapeutic components. In particular, potential interactions must be taken into account.


Subject(s)
Anxiety Disorders/epidemiology , Anxiety Disorders/psychology , Inflammation , Rheumatic Diseases/psychology , Stress, Psychological/epidemiology , Antidepressive Agents/therapeutic use , Anxiety Disorders/drug therapy , Comorbidity , Depression , Humans , Inflammation/epidemiology , Inflammation/psychology , Mental Disorders/epidemiology , Mental Disorders/psychology , Quality of Life , Rheumatic Diseases/epidemiology , Stress, Psychological/drug therapy , Stress, Psychological/psychology
3.
Versicherungsmedizin ; 64(3): 127-31, 2012 Sep 01.
Article in German | MEDLINE | ID: mdl-22997674

ABSTRACT

Psychiatric diseases and comorbidity have increased over the past years. Commonly used psychotropic drugs contain a high risk of drug interactions and adverse drug events (ADE). With a frequency of 10-12% psychotropic drugs are, among all pharmaceuticals, the most common cause of hospitalisation due to ADE. During a hospital stay the application of psychotropic drugs can also lead to adverse drug events--sometimes due to drug interactions. Currently, ADEs and drug interactions are the most frequent cause of death for in-patients (18% of all causes of death) with an overall mortality of 0.95%. As studies have shown, hospitals as well as insurers could save a considerable amount of resources by implementing a system with on-ward pharmacists, hereby reducing ADE and re-hospitalisation rates. In recent studies a large amount of current ADEs were rated as preventable. Patient impairment due to ADE is leading to an increase in liability cases with an expected 5% increase of compensation payments in 2011. To evaluate these ADE-related cases, a pharmaceutical assessment should be included in the expert trials, especially since a lack of awareness of medication errors is prevalent. When aiming towards a successful drug therapy, physicians must also consider that cheaper substances may often have an unfavourable drug interaction profile.


Subject(s)
Expert Testimony/legislation & jurisprudence , Mental Disorders/drug therapy , Psychotropic Drugs/adverse effects , Absenteeism , Comorbidity , Cost Savings/legislation & jurisprudence , Disability Evaluation , Drug Interactions , Drug Substitution/economics , Drug Therapy, Combination/adverse effects , Drug Therapy, Combination/economics , Expert Testimony/economics , Germany , Hospitalization/economics , Hospitalization/legislation & jurisprudence , Humans , Length of Stay/economics , Length of Stay/legislation & jurisprudence , Liability, Legal/economics , Medication Errors/economics , Medication Errors/legislation & jurisprudence , Mental Disorders/economics , National Health Programs/economics , National Health Programs/legislation & jurisprudence , Psychotropic Drugs/economics , Psychotropic Drugs/therapeutic use , Risk Factors , Social Security/economics , Social Security/legislation & jurisprudence
4.
Versicherungsmedizin ; 62(1): 3-8, 2010 Mar 01.
Article in German | MEDLINE | ID: mdl-20387698

ABSTRACT

Basic and clinical neurosciences have effectively advanced research on aetiology, pathogenesis and therapy options of psychiatric disorders. The objectives of the present short review were to summarise the key findings regarding the neurobiology of major depressive disorder (MDD) on the gene, cell as well as system level. Consistent with structural findings, which report alterations in regions of emotionally relevant networks of the brain in depressive disorders, findings of functional studies point to changes in an ordered interaction of ventral-limbic and dorsal-neocortical regions of the brain. Genetic and stress vulnerabilities as well as social rhythm disrupting interact to initiate a cascade of neurobiological alterations that disrupt this dynamic system. On the cellular level, monoamine as well as glutamate neurotransmission, circadian rhythm disturbance, glucocorticoids, inflammatory cytokines and brain-derived growth factors are relevant mediators of these pathological alterations. Progressive effects of recurrent and chronic MDD may then lead to further structural and functional abnormalities. Thus, treatment providers are directed to recog-nise that the factors that may initiate an MDD episode and those that maintain the illness are likely to be different. Given these long-term consequences, an essential objective of treatment must be to restore as early as possible normative functioning and prevent further neurobiological structural alterations.


Subject(s)
Brain/physiopathology , Circadian Rhythm , Depression/physiopathology , Models, Neurological , Nerve Net/physiopathology , Humans
5.
Mol Psychiatry ; 12(3): 307-17, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17211439

ABSTRACT

Emotional reactivity and regulation are fundamental to human behavior. As inter-individual behavioral variation is affected by a multitude of different genes, there is intense interest to investigate gene-gene effects. Functional sequence variation at two genes has been associated with response and resiliency to emotionally unpleasant stimuli. These genes are the catechol-O-methyltransferase gene (COMT Val158Met) and the regulatory region (5-HTTLPR) of the serotonin transporter gene. Recently, it has been proposed that 5-HTT expression is not only affected by the common S/L variant of 5-HTTLPR but also by an A to G substitution. Using functional magnetic resonance imaging, we assessed the effects of COMT Val(158)Met and both 5-HTT genotypes on brain activation by standardized affective visual stimuli (unpleasant, pleasant, and neutral) in 48 healthy subjects. Based on previous studies, the analysis of genotype effects was restricted to limbic brain areas. To determine allele-dose effects, the number of COMT Met158 alleles (i.e., lower activity of COMT) and the number of 5-HTT low expressing alleles (S and G) was correlated with the blood oxygen level-dependent (BOLD) response to pleasant or unpleasant stimuli compared to neutral stimuli. We observed an additive effect of COMT and both 5-HTT polymorphisms, accounting for 40% of the inter-individual variance in the averaged BOLD response of amygdala, hippocampal and limbic cortical regions elicited by unpleasant stimuli. Effects of 5-HTT and COMT genotypes did not affect brain processing of pleasant stimuli. These data indicate that functional brain imaging may be used to assess the interaction of multiple genes on the function of neuronal networks.


Subject(s)
Catechol O-Methyltransferase/genetics , Emotions/physiology , Limbic System/physiology , Serotonin Plasma Membrane Transport Proteins/genetics , Adult , Analysis of Variance , Brain Mapping , Genotype , Humans , Image Processing, Computer-Assisted/methods , Limbic System/blood supply , Magnetic Resonance Imaging/methods , Male , Mental Processes , Methionine/genetics , Middle Aged , Oxygen/blood , Polymorphism, Genetic , Valine/genetics
6.
J Affect Disord ; 94(1-3): 121-6, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16701903

ABSTRACT

UNLABELLED: The hippocampus is discussed as one of the key regions in the pathogenesis of Posttraumatic Stress Disorder (PTSD). MRI results concerning the volume of the hippocampus are, however, inconsistent. This may be due to the heterogeneity of patients' traumata or postprocessing of the imaging data. To overcome these problems, the present study investigates volume changes in well-characterized chronic PTSD patients in comparison to controls using two different evaluation methods. MATERIAL AND METHODS: 15 patients with chronic PTSD, traumatized at the same air show plane crash in 1988 (Ramstein, Germany), and 15 matched healthy controls participated in this study. All patients suffered from significant impairment by the PTSD; none had a history of drug or alcohol abuse. Hippocampus volume changes were processed by a semi-automated standard procedure performed with BRAINS2 as well as the voxel based morphometry (VBM) using SPM2. RESULTS: No differences in total brain grey or white matter were detected between patients and controls. No differences in total hippocampal volume or in right and left parts were seen, even when hippocampal volumes were corrected by total brain volume or correlated with clinical data. Finally, no significant differences were detected between patients and controls in hippocampal regions using VBM. DISCUSSION: This is the first study examining long-term changes in hippocampal volumes in chronic PTSD patients compared to matched controls using two different evaluation methods. Neither conventional volumetry nor VBM could detect any differences in the volume and structure. This supports the hypothesis that previously described hippocampal volume reduction is not necessarily due to PTSD or at least that, after 15 years, volume changes have been restored or have not yet developed.


Subject(s)
Hippocampus/pathology , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Stress Disorders, Post-Traumatic/diagnosis , Adult , Brain/pathology , Chronic Disease , Dominance, Cerebral/physiology , Female , Follow-Up Studies , Humans , Male , Mathematical Computing , Middle Aged , Reference Values
7.
Fortschr Neurol Psychiatr ; 73(7): 377-91, 2005 Jul.
Article in German | MEDLINE | ID: mdl-16012917

ABSTRACT

The knowledge about the development and maintenance of the posttraumatic stress disorder (PTSD) has increased significantly in the past 10 years with important insights coming from imaging studies. Through these insights PTSD has changed from "traumatic neurosis" to a biologically based psychological disorder. This paper summarises the recent literature on morphological, functional and metabolic neuroimaging on PTSD. Of special interest are four brain areas, the hyperactive amygdala, the hippocampus with volume reduction as well as the cingulate gyrus and orbitofrontal cortical regions, which may not be able to inhibit the hyperactive amygdala to trauma related stimuli. Based on these imaging data the current understanding of the pathophysiology of PTSD as well as present methodological limitations of imaging methods will be discussed.


Subject(s)
Stress Disorders, Post-Traumatic/pathology , Brain/pathology , Brain Chemistry , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Positron-Emission Tomography , Stress Disorders, Post-Traumatic/diagnostic imaging , Stress Disorders, Post-Traumatic/physiopathology , Stress Disorders, Post-Traumatic/therapy , Tomography, Emission-Computed, Single-Photon
8.
Radiologe ; 45(2): 178-85, 2005 Feb.
Article in German | MEDLINE | ID: mdl-15619067

ABSTRACT

Recently, there has been growing interest in using functional magnetic resonance imaging (fMRI) for the evaluation of psychopharmacological drugs. fMRI studies in healthy human volunteers and psychiatric patients focus on cerebral activity following acute drug administration (single challenge) and on adaptive effects on neural networks due to long-term medication. In our own fMRI studies, the effects of olanzapine or amisulpride in never treated or medication-free schizophrenic patients using robust motor, visual, and acoustic tasks was longitudinally examined. In agreement with previous reports in the literature it could be shown that, in contrast to traditional neuroleptics, atypical drugs do not decrease the activation of the sensorimotor cortex but rather normalize the reduced frontoparietal activation as well as the neuropsychological test results. This encourages the assumption that atypical antipsychotics seem to support the recovery or normalization of frontoparietal brain dysfunction in schizophrenia. However, with these new opportunities additional methodological considerations and limitations emerge.


Subject(s)
Antipsychotic Agents/administration & dosage , Brain Mapping/methods , Brain/drug effects , Brain/physiopathology , Magnetic Resonance Imaging/methods , Mental Disorders/diagnosis , Mental Disorders/drug therapy , Brain/pathology , Clinical Trials as Topic , Humans , Mental Disorders/pathology , Prognosis , Treatment Outcome
9.
Pharmacopsychiatry ; 37(4): 171-4, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15467974

ABSTRACT

BACKGROUND: Post-mortem studies with brain samples of schizophrenic patients led revealed altered GABA-ergic markers like reduced expression of the GABA transporter GAT-1. Whether this effect is due to the pathophysiology of schizophrenia or to antipsychotic treatment has not been investigated. We therefore established an animal trial of long-term antipsychotic treatment to address this question. METHODS: A total of 33 adult male rats were investigated in three cohorts of 11 animals. One group received clozapine (45 mg/kg/ day), another group haloperidol (1.5 mg/kg/day), and the third one pH-adapted water over a period of 6 months. In situ hybridization with cRNA probes specific for GABA transporters VGAT, GAT-1 and GAT-3 were performed in comparison to control animals. RESULTS: While GAT-1 was upregulated, VGAT expression declined in cortical and limbic brain regions, whereby haloperidol showed a greater effect than clozapine. GAT-3 expression was suppressed in parietal and temporal cortex. CONCLUSIONS: We thus conclude that long-term antipsychotic treatment alters GABA transporter expression in rat. The upregulation of GAT-1 contrasts with the post-mortem finding of reduced GAT-1 expression in schizophrenic patients. Our results facilitate the distinction between disease dependent changes of GABAergic markers and medication effects.


Subject(s)
Antipsychotic Agents/pharmacology , Clozapine/pharmacology , Haloperidol/pharmacology , Membrane Transport Proteins/drug effects , Membrane Transport Proteins/metabolism , Amino Acid Transport Systems/drug effects , Amino Acid Transport Systems/genetics , Amino Acid Transport Systems/metabolism , Animals , Antipsychotic Agents/administration & dosage , Brain/anatomy & histology , Brain/drug effects , Brain/metabolism , Clozapine/administration & dosage , Drug Administration Schedule , GABA Plasma Membrane Transport Proteins , Haloperidol/administration & dosage , In Situ Hybridization , Male , Membrane Transport Proteins/genetics , RNA, Complementary/drug effects , RNA, Complementary/genetics , Rats , Rats, Sprague-Dawley , Time Factors , Vesicular Inhibitory Amino Acid Transport Proteins , Vesicular Transport Proteins/drug effects , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolism , Water/administration & dosage
10.
Fortschr Neurol Psychiatr ; 72(8): 435-45, 2004 Aug.
Article in German | MEDLINE | ID: mdl-15305238

ABSTRACT

Modern neuroimaging like PET, SPECT, MR-Volumetry, functional MRI and MR-Spectroscopy has effectively advanced research on aetiology, pathogenesis and therapy options of depressive disorders. This review highlights the status of current research on this topic. Consistent with morphological findings, which report alterations in regions of emotionally relevant networks of the brain in depressive disorders, findings of functional studies point to changes in the basal ganglia, the frontal cortex and the limbic system involving the hippocampus and the amygdala. During processing of emotional cues depressive patients show different activation patterns in the regions of the frontal lobe and the amygdala. In our study of a subgroup we were also able to show deficits in processing cues independently from the emotional quality of the stimulus - especially in posterior-parietal and prefrontal areas. In healthy subjects affective modulation correlates with an ordered interaction of ventral-limbic and dorsal-neocortical regions of the brain, which become unbalanced in depressive disorders. In the future, modern neuroimaging will open promising fields of research, which aim at the identification of valid neurofunctional subgroups of the heterogeneous affective disorders and the development of more adjusted and efficient therapy strategies.


Subject(s)
Brain/diagnostic imaging , Brain/pathology , Depressive Disorder/diagnostic imaging , Depressive Disorder/pathology , Diagnostic Imaging , Animals , Brain/physiopathology , Brain Chemistry/physiology , Depressive Disorder/metabolism , Depressive Disorder/physiopathology , Humans , Magnetic Resonance Imaging , Tomography, Emission-Computed , Tomography, Emission-Computed, Single-Photon
11.
Nervenarzt ; 75(3): 258-66, 2004 Mar.
Article in German | MEDLINE | ID: mdl-15021927

ABSTRACT

Huntington's disease (HD) is an autosomal, dominant, inherited disorder of the central nervous system with characteristic neurodegenerative alterations in the basal ganglia and cortex. Dependent on the individual CAG expansion load, disease onset occurs between the third or fourth decade of life, entailing an invariably lethal progression within 10 to 20 years. Although the clinical picture is characterized equally by cognitive and psychiatric disturbances, the apparent neurodegenerative alterations and presentation as a choreatic movement disorder account for the traditional link of Huntington's disease to the field of neurology. In contrast to the traditionally emphasized core features of chorea and dementia, recent empirical evidence points to the frequent emergence of nonchoreatic motor signs and subtle cognitive and psychiatric complaints, especially in asymptomatic gene carriers and early disease stages. The case studies presented here emphasize the spectrum of neuropsychiatric phenomena associated with HD and illustrate the resulting difficulties of differential diagnosis in clinical settings. Furthermore, current scientific knowledge of HD pleiotrophy is reviewed and the diagnostic power of specific neuropsychological approaches is explained.


Subject(s)
Dementia/diagnosis , Huntington Disease/diagnosis , Neuropsychological Tests , Adult , Atrophy , Brain/pathology , Dementia/genetics , Dementia/psychology , Diagnosis, Differential , Disease Progression , Dominance, Cerebral/physiology , Female , Genetic Carrier Screening , Humans , Huntington Disease/genetics , Huntington Disease/psychology , Life Change Events , Magnetic Resonance Imaging , Male , Middle Aged , Neurologic Examination/statistics & numerical data , Psychometrics
12.
Nervenarzt ; 75(1): 16-22, 2004 Jan.
Article in German | MEDLINE | ID: mdl-14722657

ABSTRACT

Post-mortem investigations have confirmed that glutamatergic NMDA, AMPA, and kainate receptors are involved in the pathophysiology of schizophrenia. It is still unclear, however, whether the altered number of receptors is caused by the disease itself or the medication. Therefore, animal models were investigated for effects of antipsychotic medication after treatment periods of up to 6 months, the results of which are summarized here. Generally, NMDA receptor binding was found to be increased in striatum and nucleus accumbens after therapy with haloperidol, whereas clozapine only increased the number of receptors in nucleus accumbens. While haloperidol led to an increase in AMPA receptors in the posterior cingulate gyrus, striatum, insular cortex, and n. accumbens, clozapine was found to elevate ligand binding in the anterior cingulate gyrus and infralimbic cortex. Although kainate receptor binding was increased in hippocampus by both antipsychotics, clozapine was significantly more effective. In conclusion, data reveal different effects from the typical neuroleptic haloperidol and the atypical antipsychotic clozapine. The results suggest that post-mortem findings in patients with schizophrenia may at least partially be explained by drug effects and plasticity changes induced by long-term medication with antipsychotics.


Subject(s)
Antipsychotic Agents/pharmacology , Brain/drug effects , Disease Models, Animal , Receptors, Glutamate/drug effects , Schizophrenia/drug therapy , Synaptic Transmission/drug effects , Animals , Brain/pathology , Clozapine/pharmacology , Haloperidol/pharmacology , Humans , Long-Term Care , Neuronal Plasticity/drug effects , Neurons/drug effects , Neurons/pathology , Rats , Schizophrenia/pathology
13.
J Neural Transm (Vienna) ; 111(1): 91-100, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14714218

ABSTRACT

The dentate gyrus contains progenitor cells possessing the capacity to proliferate until and throughout adulthood. There is little information about the influence of antipsychotics on cell proliferation. To address this, we investigated the influence of acute and chronic haloperidol and clozapine treatment on the total number of newly dividing cells and hippocampal volume using an animal model with doses equivalent to the therapeutic range in humans. Rats were treated with either acute or 28 days haloperidol (1 mg/kg i.p. or 1,5 mg/kg/day oral) or clozapine (30 mg/kg i.p. or 45 mg/kg/day oral). After BrdU injection, immunohistochemistry was performed in serial hippocampal brain sections. Total BrdU-labeled cell number and hippocampus volume were estimated using stereological methods. Neither neuroleptic altered total number of newly dividing cells in the dentate gyrus. In contrast, chronic haloperidol treatment did increase total hippocampal volume suggesting that haloperidol alters neuroplastic processes or glial morphology rather than cell proliferation.


Subject(s)
Clozapine/administration & dosage , Haloperidol/administration & dosage , Hippocampus/anatomy & histology , Hippocampus/drug effects , Animals , Cell Division/drug effects , Cell Division/physiology , Hippocampus/physiology , Male , Rats , Rats, Sprague-Dawley
14.
Pharmacopsychiatry ; 36(6): 292-6, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14663653

ABSTRACT

BACKGROUND: Alterations in AMPA and kainate receptor binding have been revealed in post-mortem schizophrenic brains. As most patients had been treated with antipsychotics, medication effects cannot be excluded as a possible explanation for these results. METHODS: Within the framework of this animal study, we investigated [3H]AMPA and [3H]kainate receptor binding in different rat brain regions following 6 months of oral treatment with either haloperidol (1.5 mg/kg/day) or clozapine (45 mg/kg/day). RESULTS: AMPA receptor binding was increased after haloperidol treatment in the striatum, nucleus accumbens, cingulate cortex, and insular cortex. Clozapine showed increased AMPA receptor binding only in the anterior cingulate cortex. Kainate receptor binding was increased by both drugs in all hippocampal subfields. CONCLUSIONS: This altered receptor binding may be related to beneficial neuroleptic effects and side effects. Furthermore, neuroleptic therapy may contribute to some of the post-mortem findings in the striatum in schizophrenia.


Subject(s)
Brain/drug effects , Clozapine/pharmacology , Dopamine Antagonists/pharmacology , Haloperidol/pharmacology , Receptors, AMPA/drug effects , Receptors, Kainic Acid/drug effects , Serotonin Antagonists/pharmacology , Animals , Antipsychotic Agents/pharmacology , Autoradiography , Brain/metabolism , GABA Antagonists/pharmacology , Male , Rats , Rats, Sprague-Dawley , Receptors, AMPA/metabolism , Receptors, Kainic Acid/metabolism , Up-Regulation
15.
Pharmacopsychiatry ; 36 Suppl 3: S191-4, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14677078

ABSTRACT

Emotional neuroscience maps neurocircuits associated with the processing of affective stimuli. To assess gender differences in brain activation elicited by affective stimuli, we used pictures from the International Affective Picture System in a functional magnetic resonance imaging (fMRI) study. Ten male and ten female age-matched healthy volunteers were included and viewed affectively negative versus positive pictures, which were presented in an event related design. There was a significant interaction between valence of emotional stimuli and gender in the sublenticular extended amygdala (SLEA) and the rostral anterior cingulate. fMRI activation in these regions was stronger for negative compared to positive cues in women. In men fMRI activation was independent of stimulus valence. These results suggest to take gender differences into account when emotional paradigms are tested in functional brain imaging.


Subject(s)
Brain/physiology , Emotions/physiology , Magnetic Resonance Imaging , Sex Characteristics , Visual Perception/physiology , Adult , Amygdala/physiology , Cues , Female , Globus Pallidus/physiology , Gyrus Cinguli/physiology , Humans , Male , Middle Aged , Photic Stimulation , Putamen/physiology
16.
MAGMA ; 16(2): 68-76, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12884109

ABSTRACT

Significant (31)P NMR signal enhancement through heteronuclear polarisation transfer was obtained in model solutions and in vivo on a 1.5-T whole-body MR scanner equipped with two RF channels. The much higher population differences involved in proton Zeeman energy levels can be transferred to the (31)P levels with the refocused INEPT (insensitive nucleus enhancement by polarisation transfer) double-resonance experiment by means of a series of simultaneously applied broadband RF pulses. INEPT achieves a polarisation transfer from (1)H to (31)P spin states by directly reordering the populations in spin systems with heteronuclear scalar coupling. Thus, only the (31)P NMR signal of metabolites with scalar (1)H-(31)P coupling is amplified, while the other metabolite signals in the spectra are suppressed. Compared to Ernst-angle excitation, a repetition-time-dependent signal enhancement of eta=(29+/-3)% for methylene diphosphonic acid (MDPA) and eta=(56+/-1)% for phosphorylethanolamine (PE) was obtained on model solutions through optimisation of the temporal parameters of the pulse experiment. The results are in good agreement with numerical calculations of the theoretical model for the studied spin systems. With optimised echo times, in-vivo (31)P signal enhancement of the same order was obtained in studies of the human brain.


Subject(s)
Brain/metabolism , Nuclear Magnetic Resonance, Biomolecular/methods , Phosphorus/metabolism , Signal Processing, Computer-Assisted , Diphosphonates/analysis , Ethanolamines/analysis , Humans , Reproducibility of Results , Sensitivity and Specificity
17.
Fortschr Neurol Psychiatr ; 71(2): 72-83, 2003 Feb.
Article in German | MEDLINE | ID: mdl-12579470

ABSTRACT

Functional magnetic resonance imaging (fMRI) is well established for the examination of functional activity in the living brain. The method permits the development of functional activation maps during perceptual, cognitive and emotional efforts with a high temporal and spatial resolution. As of late there has been growing interest in using this technique to investigate regionally specific brain activity following the administration of drugs such as nicotine, cocaine, lorazepam, scopolamine, antipsychotics or antidepressants. Studies in experimental animals investigate signal changes associated with the administration of psychopharmacological substances in different brain areas using a high magnetising field (> 4 Tesla). FMRI-studies in healthy human volunteers and psychiatric patients focus on cerebral activity following acute drug administration (single challenge) and on adaptive effects of the CNS due to long- term medication. Their results provide insights into brain physiology and neuropharmacological mechanisms which are in turn relevant for preclinical pharmacological studies, responder analyses and for the investigation of pathogenetic models in psychiatric diseases. However, with these new opportunities, additional methodological considerations and limitations emerge. Besides the need of controlling motion artefacts, the influence of interfering psychological variables, an exact specification of the experimental design, a standardised analysis for data adjustment and technical limitations have to be considered. This article provides an overview of the underlying model of brain function, present applications, future possibilities and methodological limitations of fMRI for the understanding of human psychopharmacology.


Subject(s)
Brain/anatomy & histology , Brain/drug effects , Magnetic Resonance Imaging/methods , Psychotropic Drugs/pharmacology , Animals , Artifacts , Humans , Oxygen/blood
18.
Fortschr Neurol Psychiatr ; 70(11): 591-600, 2002 Nov.
Article in German | MEDLINE | ID: mdl-12410429

ABSTRACT

Basic perceptual or motor skills involving the central nervous system as well as the subjective present require the orderly temporal organization of internal and external information. Current research in schizophrenia increasingly centers on the accompanying neurocognitive deficits with frequent reports of altered temporal processes. There has been, however, less explicit research on the basic phenomenon of temporal order. Using concrete operationalized neuropsychological procedures the present study addressed the question whether chronic schizophrenic patients (28 medicated as well as 7 unmedicated) differ in their ability to correctly judge the temporal order of visual or acoustic stimuli when compared with a healthy control group (n = 26). Within this context we found a significant impairment in basal temporal perception among patients. Moderating variables such as medication, attention deficits or the effects of motivation as an essential explanatory factor for this finding could be excluded by statistical analysis. Instead, our findings point to a fundamental disturbance in the temporal coordination of neuronal network functions in association with schizophrenic psychoses. Within this context neurophysiological, neurochemical, neuroanatomical and neuropsychological overlapping of schizophrenia and temporal perception are being presented along with a discussion of the hypothesis that disturbances in neuronal synchronization and in timing processes at different levels are of essence and a possible underlying substrate in the schizophrenic spectrum.


Subject(s)
Cognition/physiology , Schizophrenia/physiopathology , Schizophrenic Psychology , Time Perception/physiology , Acoustic Stimulation , Dopamine/physiology , Humans , Schizophrenia/drug therapy , Schizophrenia/pathology
19.
Eur Psychiatry ; 17(5): 287-91, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12381499

ABSTRACT

The objective of this study was to develop new standardized alcohol-associated cues and assess their effects on brain activation with functional magnetic resonance imaging (fMRI). Pictures of alcoholic and neutral beverages and affectively neutral pictures were presented to 44 abstinent alcoholics and 37 age-matched healthy control subjects. We assessed the skin conductance response, and the elicited arousal and valence. Alcoholics and control subjects did not differ in arousal, valence or skin conductance response evoked by alcohol-associated and affectively neutral stimuli, while nonalcoholic beverages were rated as more unpleasant and arousing by alcoholics compared with control subjects. In the fMRI pilot study, alcohol and abstract pictures were presented to six abstinent alcoholics and induced a significant activation of brain areas associated with visual emotional processes such as the fusiform gyrus, parts of the brain reward system (basal ganglia and orbitofrontal gyrus) and further brain regions in the frontal and parietal cortices associated with the attention network. These observations suggest that standardized pictures of alcoholic beverages can be used to assess brain circuits involved in the processing and evaluation of alcohol cues.


Subject(s)
Alcoholism/psychology , Brain/anatomy & histology , Brain/drug effects , Cues , Ethanol/pharmacology , Adult , Affect , Alcoholism/physiopathology , Arousal/drug effects , Female , Galvanic Skin Response/physiology , Humans , Magnetic Resonance Imaging , Male , Photic Stimulation , Psychometrics , Random Allocation
20.
Nervenarzt ; 73(5): 428-33, 2002 May.
Article in German | MEDLINE | ID: mdl-12078020

ABSTRACT

Basic perceptual skills involving the central nervous system require the orderly temporal integration of internal as well as external information. Current research in schizophrenia increasingly centers on the accompanying neurocognitive deficits. In association with schizophrenic psychoses, there have been frequent reports of altered temporal processes, but explicit research on the perception of temporal relationship is still rare. Using concrete operationalized neuropsychological procedures, the present pilot study addressed the question whether schizophrenic patients (n = 27) differ from a healthy control group (n = 18) concerning their ability to judge correctly the temporal order of visual stimuli. We found a significant impairment in basal temporal perception among patients. Moderating variables such as antipsychotic medication, attention deficits, or motivation effects did not appear to be essential explanatory factors for this finding. Thus, our findings indicate a fundamental disturbance in the temporal coordination of neuronal network functions in association with schizophrenic psychoses and are in line with neurophysiological, neuroanatomical, and neuropsychological overlappings of schizophrenia and temporal perception.


Subject(s)
Schizophrenia/diagnosis , Schizophrenic Psychology , Time Perception , Adult , Female , Humans , Internal-External Control , Male , Middle Aged , Neuropsychological Tests , Psychiatric Status Rating Scales
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