Search Results - (Author, Cooperation:A. Heinz)

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  1. 1
    Staff View
    Publication Date:
    2014-07-22
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Adolescent ; Alcohol Drinking/*psychology ; Alcoholism/genetics/prevention & control/*psychology ; Artificial Intelligence ; Brain/physiology ; Cognition/physiology ; Environment ; Humans ; Life Change Events ; Longitudinal Studies ; *Models, Theoretical ; Personality/physiology ; Polymorphism, Single Nucleotide ; Psychology ; Reproducibility of Results ; Risk Factors
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  2. 2
    D. P. Hibar ; J. L. Stein ; M. E. Renteria ; A. Arias-Vasquez ; S. Desrivieres ; N. Jahanshad ; R. Toro ; K. Wittfeld ; L. Abramovic ; M. Andersson ; B. S. Aribisala ; N. J. Armstrong ; M. Bernard ; M. M. Bohlken ; M. P. Boks ; J. Bralten ; A. A. Brown ; M. M. Chakravarty ; Q. Chen ; C. R. Ching ; G. Cuellar-Partida ; A. den Braber ; S. Giddaluru ; A. L. Goldman ; O. Grimm ; T. Guadalupe ; J. Hass ; G. Woldehawariat ; A. J. Holmes ; M. Hoogman ; D. Janowitz ; T. Jia ; S. Kim ; M. Klein ; B. Kraemer ; P. H. Lee ; L. M. Olde Loohuis ; M. Luciano ; C. Macare ; K. A. Mather ; M. Mattheisen ; Y. Milaneschi ; K. Nho ; M. Papmeyer ; A. Ramasamy ; S. L. Risacher ; R. Roiz-Santianez ; E. J. Rose ; A. Salami ; P. G. Samann ; L. Schmaal ; A. J. Schork ; J. Shin ; L. T. Strike ; A. Teumer ; M. M. van Donkelaar ; K. R. van Eijk ; R. K. Walters ; L. T. Westlye ; C. D. Whelan ; A. M. Winkler ; M. P. Zwiers ; S. Alhusaini ; L. Athanasiu ; S. Ehrlich ; M. M. Hakobjan ; C. B. Hartberg ; U. K. Haukvik ; A. J. Heister ; D. Hoehn ; D. Kasperaviciute ; D. C. Liewald ; L. M. Lopez ; R. R. Makkinje ; M. Matarin ; M. A. Naber ; D. R. McKay ; M. Needham ; A. C. Nugent ; B. Putz ; N. A. Royle ; L. Shen ; E. Sprooten ; D. Trabzuni ; S. S. van der Marel ; K. J. van Hulzen ; E. Walton ; C. Wolf ; L. Almasy ; D. Ames ; S. Arepalli ; A. A. Assareh ; M. E. Bastin ; H. Brodaty ; K. B. Bulayeva ; M. A. Carless ; S. Cichon ; A. Corvin ; J. E. Curran ; M. Czisch ; G. I. de Zubicaray ; A. Dillman ; R. Duggirala ; T. D. Dyer ; S. Erk ; I. O. Fedko ; L. Ferrucci ; T. M. Foroud ; P. T. Fox ; M. Fukunaga ; J. R. Gibbs ; H. H. Goring ; R. C. Green ; S. Guelfi ; N. K. Hansell ; C. A. Hartman ; K. Hegenscheid ; A. Heinz ; D. G. Hernandez ; D. J. Heslenfeld ; P. J. Hoekstra ; F. Holsboer ; G. Homuth ; J. J. Hottenga ; M. Ikeda ; C. R. Jack, Jr. ; M. Jenkinson ; R. Johnson ; R. Kanai ; M. Keil ; J. W. Kent, Jr. ; P. Kochunov ; J. B. Kwok ; S. M. Lawrie ; X. Liu ; D. L. Longo ; K. L. McMahon ; E. Meisenzahl ; I. Melle ; S. Mohnke ; G. W. Montgomery ; J. C. Mostert ; T. W. Muhleisen ; M. A. Nalls ; T. E. Nichols ; L. G. Nilsson ; M. M. Nothen ; K. Ohi ; R. L. Olvera ; R. Perez-Iglesias ; G. B. Pike ; S. G. Potkin ; I. Reinvang ; S. Reppermund ; M. Rietschel ; N. Romanczuk-Seiferth ; G. D. Rosen ; D. Rujescu ; K. Schnell ; P. R. Schofield ; C. Smith ; V. M. Steen ; J. E. Sussmann ; A. Thalamuthu ; A. W. Toga ; B. J. Traynor ; J. Troncoso ; J. A. Turner ; M. C. Valdes Hernandez ; D. van 't Ent ; M. van der Brug ; N. J. van der Wee ; M. J. van Tol ; D. J. Veltman ; T. H. Wassink ; E. Westman ; R. H. Zielke ; A. B. Zonderman ; D. G. Ashbrook ; R. Hager ; L. Lu ; F. J. McMahon ; D. W. Morris ; R. W. Williams ; H. G. Brunner ; R. L. Buckner ; J. K. Buitelaar ; W. Cahn ; V. D. Calhoun ; G. L. Cavalleri ; B. Crespo-Facorro ; A. M. Dale ; G. E. Davies ; N. Delanty ; C. Depondt ; S. Djurovic ; W. C. Drevets ; T. Espeseth ; R. L. Gollub ; B. C. Ho ; W. Hoffmann ; N. Hosten ; R. S. Kahn ; S. Le Hellard ; A. Meyer-Lindenberg ; B. Muller-Myhsok ; M. Nauck ; L. Nyberg ; M. Pandolfo ; B. W. Penninx ; J. L. Roffman ; S. M. Sisodiya ; J. W. Smoller ; H. van Bokhoven ; N. E. van Haren ; H. Volzke ; H. Walter ; M. W. Weiner ; W. Wen ; T. White ; I. Agartz ; O. A. Andreassen ; J. Blangero ; D. I. Boomsma ; R. M. Brouwer ; D. M. Cannon ; M. R. Cookson ; E. J. de Geus ; I. J. Deary ; G. Donohoe ; G. Fernandez ; S. E. Fisher ; C. Francks ; D. C. Glahn ; H. J. Grabe ; O. Gruber ; J. Hardy ; R. Hashimoto ; H. E. Hulshoff Pol ; E. G. Jonsson ; I. Kloszewska ; S. Lovestone ; V. S. Mattay ; P. Mecocci ; C. McDonald ; A. M. McIntosh ; R. A. Ophoff ; T. Paus ; Z. Pausova ; M. Ryten ; P. S. Sachdev ; A. J. Saykin ; A. Simmons ; A. Singleton ; H. Soininen ; J. M. Wardlaw ; M. E. Weale ; D. R. Weinberger ; H. H. Adams ; L. J. Launer ; S. Seiler ; R. Schmidt ; G. Chauhan ; C. L. Satizabal ; J. T. Becker ; L. Yanek ; S. J. van der Lee ; M. Ebling ; B. Fischl ; W. T. Longstreth, Jr. ; D. Greve ; H. Schmidt ; P. Nyquist ; L. N. Vinke ; C. M. van Duijn ; L. Xue ; B. Mazoyer ; J. C. Bis ; V. Gudnason ; S. Seshadri ; M. A. Ikram ; N. G. Martin ; M. J. Wright ; G. Schumann ; B. Franke ; P. M. Thompson ; S. E. Medland
    Nature Publishing Group (NPG)
    Published 2015
    Staff View
    Publication Date:
    2015-01-22
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Adolescent ; Adult ; Aged ; Aged, 80 and over ; Aging/genetics ; Apoptosis/genetics ; Brain/*anatomy & histology ; Caudate Nucleus/anatomy & histology ; Child ; Female ; Gene Expression Regulation, Developmental/genetics ; Genetic Loci/genetics ; Genetic Variation/*genetics ; *Genome-Wide Association Study ; Hippocampus/anatomy & histology ; Humans ; Magnetic Resonance Imaging ; Male ; Membrane Proteins/genetics ; Middle Aged ; Organ Size/genetics ; Putamen/anatomy & histology ; Sex Characteristics ; Skull/anatomy & histology ; Young Adult
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  3. 3
    Staff View
    Publication Date:
    2018-05-22
    Publisher:
    American Physical Society (APS)
    Print ISSN:
    0556-2813
    Electronic ISSN:
    1089-490X
    Topics:
    Physics
    Keywords:
    Nuclear Reactions
    Published by:
    http://www.aps.org/

    Latest Papers from Table of Contents or Articles in Press
  4. 4
    Staff View
    Publication Date:
    2015-06-13
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Adolescent ; Adult ; Animals ; Brain/metabolism/*physiology ; Female ; Gene Expression ; Humans ; Ion Channels/*genetics ; Magnetic Resonance Imaging ; Male ; Mice ; Nerve Net/metabolism/*physiology ; Neural Pathways/metabolism/physiology ; Polymorphism, Genetic ; Rest/*physiology ; Synapses/metabolism/physiology ; *Transcriptome ; Young Adult
    Published by:
    http://www.aaas.org/

    Latest Papers from Table of Contents or Articles in Press
  5. 5
    HESS, MAX W. ; MUELLER, CHRISTOPH ; SCHAFFNER, THOMAS ; GERBER, HEINZ A. ; EGGLI, PETER ; COTTIER, HANS

    Oxford, UK : Blackwell Publishing Ltd
    Published 1985
    Staff View
    ISSN:
    1749-6632
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Natural Sciences in General
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1749-6632.1985.tb20811.x

    Articles: DFG German National Licenses
  6. 6
    Staff View
    ISSN:
    0370-2693
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1016/0370-2693(94)90017-5

    Articles: DFG German National Licenses
  7. 7
    Staff View
    ISSN:
    0370-2693
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1016/0370-2693(94)90937-7

    Articles: DFG German National Licenses
  8. 8
    Heinz, A. ; Wöhrle, J. ; Schöls, L. ; Klotz, P. ; Kühn, W. ; Przuntek, H.
    Springer
    Published 1992
    Staff View
    ISSN:
    1435-1463
    Keywords:
    OPCA ; continuous dopaminergic stimulation ; dopaminergica ; dysphagia ; dysarthria
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Notes:
    Summary Four patients with sporadic olivopontocerebellar atrophy (OPCA) and severe signs of Parkinsonism received continuous subcutaneous lisuride infusion via a small external pump. All 4 patients benefitted from this treatment: 3 showed an overall improvement in motor performance, in 1 patient mainly dysphagia and dysarthria improved. Therapeutic benefit lasted for at least 6 months of follow up. With a daily dose of 1.0 mg of subcutaneous lisuride, treatment limitations were reached in the form of dysphagia, probably due to oropharyngeal dystonia. Subcutaneous lisuride infusion should be taken into consideration in OPCA patients with signs of Parkinsonism if oral dopaminergic treatment has failed earlier on.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF01250796

    Articles: DFG German National Licenses
  9. 9
    Staff View
    ISSN:
    1434-601X
    Keywords:
    PACS:23.40.-s β decay, double β decay, electron and muon capture – 27.30.+t 20 ≤ A ≤ 38 – 27.50.+e 59 ≤ A ≤ 89
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract: The unknown β-decay half-lives of 22 isotopes far off stability (5 〈 T Z 〈 10) in the region from Ti to Ni were measured at GSI, Darmstadt. The nuclei were produced in a fragmentation reaction of 500 A.MeV 86Kr-projectile impinging on a thick Be target. The isotopes of interest were separated and identified with the fragment separator, FRS, by a combination of Bρ,Z, and ToF techniques. An additional range separation was performed by a selective implantation into granular detectors. The spatial and time correlations of the implant with the consecutively detected β-particles were used to determine the unknown half-lives. For nuclei far off stability, β-decay chains were measured and analyzed as well, leading to an even more reliable evaluation of the lifetimes. The large discrepancies found between the measured and the theoretical values emphasize that most recent theoretical work is not an improvement over calculations made almost a decade ago.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s100500050062

    Articles: DFG German National Licenses
  10. 10
    Staff View
    ISSN:
    1434-601X
    Keywords:
    PACS:25.75.-q – 25.70.Mn – 21.10.Ft – 21.10.Gv – 27.50.+e – 27.50.+j – 24.10.Pa
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract: Projectile fragmentation of 238U in a lead target was investigated at a bombarding energy of 750 A MeV. Isotopic production cross sections of about 250 different projectile fragments in the element range Z= 30–53 were measured with the FRagment Separator (FRS). The magnetic selection and the kinematical analysis of the measured isotopes allowed to disentangle fission and fragmentation residues. The mass loss of these residues indicates a violent collision where a large amount of energy is dissipated. The position of the fragmentation corridor defined by the measured residues was used to determine an effective proton-evaporation barrier.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s100500050108

    Articles: DFG German National Licenses
  11. 11
    Staff View
    ISSN:
    1434-601X
    Keywords:
    PACS:25.85.-w Fission reactions – 25.75.-q Relativistic heavy-ion collosions
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract: Fragments of relativistic 750 A.MeV U-projectiles were investigated by using the fragment separator FRS for magnetic selection of reaction products including ray-tracing and ΔE-ToF techniques. For elements between Ge and Sb, measurements of isotopic yield distributions and velocities revealed three processes: fragmentation, low-energy fission, and high-energy fission. The last of these regimes is presently reported. First and second moments of distributions of mass numbers, atomic numbers and velocities of the corresponding fragments allowed us to identify 101 43Tc56 as the most probable fragment of a high energy symmetric fission reaction. Moreover, we could deduce a hypothetical mean fissioning fragmentation product 208Rn and its highly excited pre-fragmentation parent 227Ra produced in a primary abrasion reaction at an excitation energy of about 290 MeV.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s100500050107

    Articles: DFG German National Licenses
  12. 12
    Staff View
    ISSN:
    1434-601X
    Keywords:
    21.10.Ft ; 25.70.Np ; 27.40.+Z
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract At the projectile-fragment separator FRS of GSI, relativistic secondary beams of about 520 MeV/nucleon were produced by fragmentation of a primary beam of58Ni at 650 MeV/nucleon in a beryllium target. By means of aΔE—Bρ—TOF measurement, the fragments have been identified and their charge-changing probabilities in targets of CH2, C, Al, and Pb have been determined. We describe the results for the total charge-changing cross sections in this first paper, whereas a second article deals with the partial charge-changing cross sections. At the drip line, the measured charge-changing cross sections exhaust close to 100% of the total interaction cross sections as calculated with semiempirical models. The measurements at the proton drip line with low-Z targets indicate that only a very small increase of the cross sections may be observed, whereas the measurements with a lead target show that no significant increase of the total charge-changing cross sections is present which would be a hint for low-lying dipole strength. Our experimental data are compared to Glauber-type calculations.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF01292761

    Articles: DFG German National Licenses
  13. 13
    Staff View
    ISSN:
    1434-601X
    Keywords:
    24.30.Cz ; 25.75.+r
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract As part of a comprehensive study of uranium fragmentation at relativistic energies at the GSI projectile fragment separator, FRS, inclusive neutron-removal cross sections have been measured for severalxn channels at projectile energies of 600 and 950A MeV using targets of Al, Cu and Pb. The variation of the experimental cross sections with target nuclear charge is used to disentangle nuclear and electromagnetic contributions. The electromagnetic cross sections agree surprisingly well with a simple harmonic oscillator calculation of giant dipole resonances based on measured photonuclear cross sections and do not require an extra enhancement of the two-phonon giant dipole excitation as concluded from similar measurements with197Au.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF01298903

    Articles: DFG German National Licenses
  14. 14
    Staff View
    ISSN:
    1434-601X
    Keywords:
    21.60.C5 ; 27.50+e ; 25.85-w
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Physics
    Notes:
    Abstract We report the first observation of the doubly magic nucleus78Ni50 and the heavy isotopes77Ni,73,74,75Co,80Cu. The isotopes were produced by nuclear fission in collisions of 750 A·MeV projectiles of238U on Be target nuclei. The fully-stripped fission products were separated in-flight by the fragment separator FRS and identified event-by-event by measuring the magnetic rigidity, the trajectory, the energy deposit, and the time of flight. Production cross-sections and fission yields for the new Ni-isotopes are given.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF01299748

    Articles: DFG German National Licenses
  15. 15
    Frank, Martin ; Peraus, Katrin ; Staab, Heinz A.
    Springer
    Published 1996
    Staff View
    ISSN:
    0948-5023
    Keywords:
    High-Temperature MD Simulations ; Confor-mational Analysis ; Porphyrin-Quinone Systems ; Photosynthesis Models
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Notes:
    Abstract Photoinduced electron transfer reactions play an important role in the primary step of the biological photosynthesis process. In an attempt to understand better the mechanism of the charge separation organic donor-acceptor molecules containing porphyrins and quinones were designed as photosynthesis models. In order to study the structure dependence of the photoinduced electron transfer twofold and fourfold bridged porphyrin-quinone systems with increasing donor-acceptor distance were synthesized (Figure 1) [1, 2, 3]. It was assumed that in these molecules the porphyrin and quinone should be linked in a rigid and well-defined orientation. To verify this assumption the conformational behavior of these systems was studied by high-temperature MD simulations in combination with conformational analysis of selected minimized structures [4, 5].
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s0089460020383

    Articles: DFG German National Licenses
  16. 16
    Staff View
    ISSN:
    0168-583X
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    http://linkinghub.elsevier.com/retrieve/pii/0168-583X(89)91019-7

    Articles: DFG German National Licenses
  17. 17
    Staff View
    ISSN:
    0168-583X
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1016/0168-583X(94)95436-4

    Articles: DFG German National Licenses
  18. 18
    Heinz, A.
    Springer
    Published 2000
    Staff View
    ISSN:
    1433-0407
    Keywords:
    Schlüsselwörter Synaptische Dopaminkonzentration ; phasische Dopaminfreisetzung ; SPECT ; IBZM ; AMPT ; Key words Synaptic dopamine concentration ; phasic dopamine release
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Description / Table of Contents:
    Summary The dopamine hypothesis of schizophrenia was based on the neuroleptical blockade of central dopamine D2 receptors. Brain imaging studies, however, generally failed to demonstrate a significant increase in central D2 receptors among schizophrenic patients. Using a novel approach, the group of Laruelle and Abi-Dargham was now able to demonstrate that schizophrenic patients have increased synaptic dopamine concentrations in the striatum. Endogenous dopamine competes with a radioligand for binding at dopamine D2 receptors; compared to healthy control subjects, blockade of dopamine production in neuroleptic-naive schizophrenic patients induced a significantly higher increase in D2 binding of the infused radioligand, indicating higher endogenous synaptic dopamine. A similar increase in D2 binding was also observed in drug-free schizophrenics who had previously been treated with neuroleptics; these patients also showed an increased density of striatal D2 receptors, most likely due to counteradaptive upregulation of D2 receptors during neuroleptic medication. The Columbia study provides an important indication of hyperdopaminergic function in schizophrenia.
    Notes:
    Zusammenfassung Die Dopaminhypothese der Schizophrenien gründet sich auf die Beobachtung der neuroleptikabedingten Blockade zentraler Dopamin-D2-Rezeptoren. Bildgebende Studien zeigten jedoch keine Erhöhung der zentralen Dopaminrezeptoren. Mit einer neuartigen Verfahrensweise konnte jetzt die Arbeitsgruppe von Laruelle und Abi-Dargham an der Columbia Universität zeigen, dass bisher unmedizierte schizophrene Patienten eine erhöhte Dopaminkonzentration in den striären Synapsen aufweisen. Das endogene Dopamin konkurriert mit dem Radioliganden um die Bindung am D2-Rezeptor; die Blockade der Dopaminproduktion führte bei bisher unbehandelten schizophrenen Patienten zu einem stärkeren Anstieg der Bindung des infundierten Radioliganden an zentrale D2-Rezeptoren als dies bei den gesunden Kontrollpersonen der Fall war, was auf erhöhte synaptische Dopaminkonzentrationen bei diesen Patienten hinweist. Auch bei medikationsfreien, aber bereits früher mit Neuroleptika behandelten Patienten stieg die D2-Bindung stärker an als bei Kontrollpersonen, zudem war bei diesen Patienten die Dichte der striären D2-Rezeptoren erhöht, wahrscheinlich als Ausdruck einer Gegenregulation im Rahmen der früheren neuroleptischen Therapie. Die Studie ist ein entscheidender Hinweis auf das Vorliegen einer erhöhten dopaminergen Neurotransmission bei schizophrenen Patienten.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s001150050008

    Articles: DFG German National Licenses
  19. 19
    Heinz, A.
    Springer
    Published 1999
    Staff View
    ISSN:
    1433-0407
    Keywords:
    Schlüsselwörter Serotonin ; Verhaltensinhibierendes System ; Impulsivität ; Aggression ; Depression ; Key words Serotonin ; Behavior inhibition system ; impulsivity
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Description / Table of Contents:
    Summary Dysfunction of serotonergic neurotransmission has been associated with two different psychopathological syndromes – impulsive aggressivity resulting form a lack of stimulation of the “behavior inhibition system” on the one hand and the manifestation of clinical depression and compulsive syndromes on the other. The examination of primate behavior provides a model which may reconciliate these seemingly contradictory hypotheses. According to primate experiments, monoaminergic depletion results in anxious and desperate behavior only if the individual has previously been exposed to social isolation stress, which in turn induces a decrease in the central serotonin turnover rate. Young non-human primates who experience early social separation stress are anxious and fearful, while as adults they tend to be aggressive, consume excessive amounts of alcohol and are less intoxicated by alcohol intake. These observation indicate the importance of social separation stress in the pathogenesis of alcoholism and antisocial behavior and may point to prophylactic and pharmacological treatment strategies.
    Notes:
    Zusammenfassung Eine Dysfunktion serotonerger Transmission wurde mit zwei verschiedenen psychopathologischen Syndromen in Verbindung gebracht. Einerseits wurde der serotonergen Neurotransmission eine wesentliche Rolle in der Stimulation des “verhaltensinhibierenden Systems” zuerkannt und postuliert, daß ein verminderter Serotoninumsatz zur Enthemmung impulsiver und aggressiver Verhaltensweisen führt. Andererseits gibt es Hinweise auf die Bedeutung einer verminderten serotonergen Transmission in der Pathogenese der Depression und der Angsterkrankungen. Eine mögliche Deutung der vordergründig widersprüchlichen Befunde ergibt sich aus der Untersuchung serotonerger Transmission bei Primaten. Eine pharmakogen induzierte Verarmung an monoaminergen Neurotransmittern führt demnach nur dann zu depressionsanalogen Verhaltensweisen, wenn in der individuellen Entwicklung mehrfach Phasen sozialer Isolation durchlebt wurden. Umgekehrt ist soziale Isolation bei jungen Primaten mit einem verminderten Serotoninumsatz, verstärkter Ängstlichkeit und sozialer Inkompetenz assoziiert, während sich bei diesen Primaten im Erwachsenenalter eine erhöhte Aggressivität und Alkoholtoleranz und ein erhöhter freiwilliger Alkoholkonsum nachweisen lassen. Diese Befunde unterstreichen die Bedeutung von Streß- und Lernfaktoren in der Ausgestaltung der psychopathologischen Korrelate einer serotonergen Dysfunktion und verweisen auf mögliche prophylaktische und pharmakologische Behandlungsoptionen.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s001150050512

    Articles: DFG German National Licenses
  20. 20
    Heinz, A.
    Springer
    Published 1999
    Staff View
    ISSN:
    1433-0407
    Keywords:
    Schlüsselwörter Anhedonie ; Dopaminerges Verstärkungssystem ; Negativsymptomatik ; „Incentive salience” ; Stimulus-induzierte Dopaminfreisetzung ; Key words Anhedonia ; Dopaminergic reward system ; Negative symptoms ; Incentive salience ; Stimulus-induced dopamine release
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Description / Table of Contents:
    Summary The dopaminergic reward system is activated by primary rewarding factors such as food, sexual activity and parental care. Its activation enhences the occurency of behaviors which induced the stimulation of dopaminergic neurotransmission. Indications of a dysfunction of the dopaminergic reward system are found in major depression, schizophrenia, and addictive disorders. It has been hypothesized that dysfunction of the dopaminergic reward system is associated with anhedonia, the inability to experience pleasure. However, animal studies indicate that a reduction of central dopaminergic neurotransission is associated with a de- crease in incentive salience of reward-indi-cating stimuli and not with anhedonia per se. Sensitization of dopaminergic neurotransmission, on the other hand, seems to induce cue-dependent craving in addicted patients. In schizophrenia, phasic, stimulus-dependent dopamine release in the striatum may play a role in the abnormal attribution of salience to previously neutral stimuli.
    Notes:
    Zusammenfassung Das dopaminerge Verstärkungssystem wird durch sog. primäre Verstärker wie Essen, sexuelle Aktivität und elterliches Fürsorgeverhalten angesprochen. Seine Aktivierung führt zum gehäuften Auftreten all jener Verhaltensweisen, die zu seiner Stimulation beigetragen haben. Hinweise auf Störungen zentraler dopaminerger Transmission finden sich bei so unterschiedlichen Krankheitsbildern wie der majoren Depression, der Schizophrenie und bei Abhängigkeitserkrankungen. Damit stellt sich die Frage, ob Anhedonie, der „Verlust der Lebensfreude”, als nosologieübergreifendes Korrelat einer Dysfunktion des dopaminergen Verstärkungssystems auftritt. In Tierversuchen ergaben sich Hinweise darauf, daß eine verminderte dopaminerge Neurotransmission mit einer reduzierten Aufmerksamkeitszuwendung gegenüber belohnungsanzeigenden Stimuli und nicht mit Anhedonie per se assoziiert ist. Demgegenüber induziert eine Sensitivierung des dopaminergen Systems bei Abhängigkeitserkrankungen möglicherweise das stimulus-abhängige Verlangen nach der Suchtsubstanz. Eine Enthemmung der phasischen, stimulus-induzierten Dopaminfreisetzung im Striatum könnte auch in der Pathogenese der Schizophrenie von Bedeutung sein und dazu führen, daß bislang neutralen Stimuli eine besondere Bedeutung zugeschrieben wird.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s001150050454

    Articles: DFG German National Licenses