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1.
Front Psychol ; 14: 1153377, 2023.
Article in English | MEDLINE | ID: mdl-37034960

ABSTRACT

Background: Metacognitive Training for Depression in older adults (MCT-Silver; www.uke.de/mct-silver) is a cognitive-behavioral based group intervention that aims at reducing depression by targeting (meta)cognitive beliefs and rumination. In the present study, it was examined whether negative cognitive beliefs, positive metacognitive beliefs and/or rumination may be implicated as mediators of MCT-Silver's effects on depression. Materials and methods: We conducted a secondary analysis of a randomized controlled trial comparing MCT-Silver to an active control intervention (cognitive remediation) including 66 older adults (60 years and older) with complete baseline data. Clinician-rated (Hamilton Depression Rating Scale) and self-reported (Beck Depression Inventory-II) depression, negative cognitive beliefs (Dysfunctional Attitudes Scale-18B), positive metacognitive beliefs (positive beliefs subscale; Metacognition Questionnaire-30) and rumination (10-item Ruminative Response Scale) were assessed before (pre) and after 8 weeks of treatment (post), as well as 3 months later (follow-up). It was examined whether change in depression (pre- to follow-up) was mediated by change in negative cognitive beliefs, positive metacognitive beliefs and/or rumination (pre- to post-assessment). Results: Mediation results differed for self-reported vs. clinician-rated depression. The effect of MCT-Silver on reduction in clinician-rated depression was mediated by a reduction in self-reported rumination, whereas reduction in self-reported depression was mediated by a reduction in negative cognitive beliefs. Positive metacognitive beliefs were not a significant mediator for either outcome. Conclusion: The current study provides initial evidence for the roles of negative cognitive beliefs and rumination in the treatment of depression in later life with MCT-Silver. Given the divergence of findings and lack of causal precedence, mechanisms of change for MCT-Silver cannot yet be equivocally identified.

2.
Fortschr Neurol Psychiatr ; 90(4): 173-190, 2022 Apr.
Article in German | MEDLINE | ID: mdl-35443282

ABSTRACT

Bipolar affective disorder (short: bipolar disorder) describe a group of affective disorders characterised by depressive as well as manic/hypomanic episodes. The article deals with the diagnostic and therapeutic challenges of bipolar II disorder.


Subject(s)
Bipolar Disorder , Bipolar Disorder/diagnosis , Bipolar Disorder/epidemiology , Bipolar Disorder/therapy , Humans , Mood Disorders
3.
Nat Commun ; 13(1): 1431, 2022 Mar 17.
Article in English | MEDLINE | ID: mdl-35301292

ABSTRACT

Fixing molecules in space is a crucial step for the imaging of molecular structure and dynamics. Here, we demonstrate three-dimensional (3D) field-free alignment of the prototypical asymmetric top molecule indole using elliptically polarized, shaped, off-resonant laser pulses. A truncated laser pulse is produced using a combination of extreme linear chirping and controlled phase and amplitude shaping using a spatial-light-modulator (SLM) based pulse shaper of a broadband laser pulse. The angular confinement is detected through velocity-map imaging of H+ and C2+ fragments resulting from strong-field ionization and Coulomb explosion of the aligned molecules by intense femtosecond laser pulses. The achieved three-dimensional alignment is characterized by comparing the result of ion-velocity-map measurements for different alignment directions and for different times during and after the alignment laser pulse to accurate computational results. The achieved strong three-dimensional field-free alignment of [Formula: see text] demonstrates the feasibility of both, strong three-dimensional alignment of generic complex molecules and its quantitative characterization.

4.
Faraday Discuss ; 228(0): 413-431, 2021 May 27.
Article in English | MEDLINE | ID: mdl-33570531

ABSTRACT

We present a time-resolved study of the photodissociation dynamics of OCS after UV-photoexcitation at λ = 237 nm. OCS molecules (X1Σ+) were primarily excited to the 11A'' and the 21A' Renner-Teller components of the 1Σ- and 1Δ states. Dissociation into CO and S fragments was observed through time-delayed strong-field ionisation and imaging of the kinetic energy of the resulting CO+ and S+ fragments by intense 790 nm laser pulses. Surprisingly, fast oscillations with a period of ∼100 fs were observed in the S+ channel of the UV dissociation. Based on wavepacket-dynamics simulations coupled with a simple electrostatic-interaction model, these oscillations do not correspond to the known highly-excited rotational motion of the leaving CO(X1Σ+, J ≫ 0) fragments, which has a timescale of ∼140 fs. Instead, we suggest to assign the observed oscillations to the excitation of vibrational wavepackets in the 23A'' or 21A'' states of the molecule that predissociate to form S(3PJ) photoproducts.

5.
Nat Commun ; 10(1): 3364, 2019 Jul 29.
Article in English | MEDLINE | ID: mdl-31358749

ABSTRACT

Recording molecular movies on ultrafast timescales has been a longstanding goal for unravelling detailed information about molecular dynamics. Here we present the direct experimental recording of very-high-resolution and -fidelity molecular movies over more than one-and-a-half periods of the laser-induced rotational dynamics of carbonylsulfide (OCS) molecules. Utilising the combination of single quantum-state selection and an optimised two-pulse sequence to create a tailored rotational wavepacket, an unprecedented degree of field-free alignment, 〈cos2θ2D〉 = 0.96 (〈cos2θ〉 = 0.94) is achieved, exceeding the theoretical limit for single-pulse alignment. The very rich experimentally observed quantum dynamics is fully recovered by the angular probability distribution obtained from solutions of the time-dependent Schrödinger equation with parameters refined against the experiment. The populations and phases of rotational states in the retrieved time-dependent three-dimensional wavepacket rationalises the observed very high degree of alignment.

6.
J Chem Phys ; 150(24): 244301, 2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31255082

ABSTRACT

Measurements on the strong-field ionization of carbonyl sulfide molecules by short, intense, 2 µm wavelength laser pulses are presented from experiments where angle-resolved photoelectron distributions were recorded with a high-energy velocity map imaging spectrometer, designed to reach a maximum kinetic energy of 500 eV. The laser-field-free elastic-scattering cross section of carbonyl sulfide was extracted from the measurements and is found in good agreement with previous experiments, performed using conventional electron diffraction. By comparing our measurements to the results of calculations, based on the quantitative rescattering theory, the bond lengths and molecular geometry were extracted from the experimental differential cross sections to a precision better than ±5 pm and in agreement with the known values.

7.
J Chem Phys ; 148(22): 221105, 2018 Jun 14.
Article in English | MEDLINE | ID: mdl-29907031

ABSTRACT

A new technique for obtaining switched wave packets using spectrally truncated chirped laser pulses is demonstrated experimentally and numerically by one-dimensional alignment of both linear and asymmetric top molecules. Using a simple long-pass transmission filter, a pulse with a slow turn-on and a rapid turn-off is produced. The degree of alignment, characterized by ⟨cos2 θ2D⟩, rises along with the pulse intensity and reaches a maximum at the peak of the pulse. After truncation, ⟨cos2 θ2D⟩ drops sharply but exhibits pronounced half and full revivals. The experimental alignment dynamics trace agrees very well with a numerically calculated trace based on the solution of the time-dependent Schrödinger equation. However, the extended periods of field-free alignment of asymmetric tops following pulse truncation reported previously are not reproduced in our work.

8.
Phys Chem Chem Phys ; 19(30): 19733-19739, 2017 Aug 02.
Article in English | MEDLINE | ID: mdl-28561126

ABSTRACT

We demonstrate the experimental realization of impulsive alignment of carbonyl sulfide (OCS) molecules at the Low Density Matter Beamline (LDM) at the free-electron laser FERMI. OCS molecules in a molecular beam were impulsively aligned using 200 fs pulses from a near-infrared laser. The alignment was probed through time-delayed ionization above the sulphur 2p edge, resulting in multiple ionization via Auger decay and subsequent Coulomb explosion of the molecules. The ionic fragments were collected using a time-of-flight mass spectrometer and the analysis of ion-ion covariance maps confirmed the correlation between fragments after Coulomb explosion. The analysis of the CO+ and S+ channels allowed us to extract the rotational dynamics, which is in agreement with our theoretical description as well as with previous experiments. This result opens the way for a new class of experiments at LDM within the field of coherent control of molecules with the possibilities that a precisely synchronized optical-pump XUV-probe laser setup like FERMI can offer.

9.
PLoS One ; 8(12): e83414, 2013.
Article in English | MEDLINE | ID: mdl-24376698

ABSTRACT

BACKGROUND: The processing of reward and punishment stimuli in humans appears to involve brain oscillatory activity of several frequencies, probably each with a distinct function. The exact nature of associations of these electrophysiological measures with impulsive or risk-seeking personality traits is not completely clear. Thus, the aim of the present study was to investigate event-related oscillatory activity during reward processing across a wide spectrum of frequencies, and its associations with impulsivity and sensation seeking in healthy subjects. METHODS: During recording of a 32-channel EEG 22 healthy volunteers were characterized with the Barratt Impulsiveness and the Sensation Seeking Scale and performed a computerized two-choice gambling task comprising different feedback options with positive vs. negative valence (gain or loss) and high or low magnitude (5 vs. 25 points). RESULTS: We observed greater increases of amplitudes of the feedback-related negativity and of activity in the theta, alpha and low-beta frequency range following loss feedback and, in contrast, greater increase of activity in the high-beta frequency range following gain feedback. Significant magnitude effects were observed for theta and delta oscillations, indicating greater amplitudes upon feedback concerning large stakes. The theta amplitude changes during loss were negatively correlated with motor impulsivity scores, whereas alpha and low-beta increase upon loss and high-beta increase upon gain were positively correlated with various dimensions of sensation seeking. CONCLUSIONS: The findings suggest that the processing of feedback information involves several distinct processes, which are subserved by oscillations of different frequencies and are associated with different personality traits.


Subject(s)
Impulsive Behavior/physiology , Neurons/cytology , Personality/physiology , Reward , Adult , Electroencephalography , Female , Healthy Volunteers , Humans , Male
10.
Eur Neuropsychopharmacol ; 23(11): 1606-10, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23452563

ABSTRACT

We carried out dynamic [(18)F]fallypride PET scans to measure cerebral dopamine D2/3 receptor availability in a 23-year old patient experiencing a severe withdrawal syndrome upon voluntary abstinence from "Spice", a pre-packaged herbal smoking thought to contain synthetic cannabinoids. Upon admission to the clinic, the patient experienced craving, affective symptoms and a range of somatic complaints, which resolved after several days' monitored abstinence. PET scans were performed on the day of admission, and one week later. Estimates of [(18)F]fallypride binding potential (BPND) were obtained in striatal and extrastriatal brain regions, and compared to results of age-matched healthy control subjects. Upon admission, [(18)F]fallypride BPND was reduced by 20% in the patient's striatum and also in extra-striatal regions. During short-term follow-up upon detoxification, the BPND increased to normal values. This study shows substantial short-term alterations of dopamine D2/3 receptor availability in a patient before and after acute detoxification from "Spice Gold", thus providing first evidence of reversible effects on dopamine receptors of heavy use of a herbal smoking blend.


Subject(s)
Brain/metabolism , Plant Preparations/administration & dosage , Plant Preparations/adverse effects , Receptors, Dopamine D2/metabolism , Receptors, Dopamine D3/metabolism , Substance Withdrawal Syndrome/metabolism , Benzamides , Brain/diagnostic imaging , Case-Control Studies , Fluorine Radioisotopes , Functional Neuroimaging , Humans , Inactivation, Metabolic , Male , Radionuclide Imaging , Substance Withdrawal Syndrome/diagnostic imaging , Young Adult
11.
Psychiatry Res ; 208(2): 194-6, 2013 Jul 30.
Article in English | MEDLINE | ID: mdl-23246244

ABSTRACT

Autoimmune encephalitis associated with IgG antibodies to the N-methyl-d-aspartic acid receptor subunit NR1 (NMDAR) presents with neurological symptoms, such as seizures, and especially psychiatric symptoms, such as hallucinations, psychosis, agitation and anxiety. To date, however, the pathological relevance of IgM NMDAR antibodies remains elusive. Here, we describe clinical, neuroradiological and neurobiological findings of a 28-year-old male presenting with IgM NMDAR antibodies coincident with autoimmune encephalitis characterized by symptoms of bipolar disorder. After repeated steroid treatment, cognitive and psychiatric abnormalities improved and no NMDAR antibody was detectable. Using primary neuronal cultures, we demonstrate that patient's serum containing IgM NMDAR antibodies reduced the detection of NMDAR on neuronal cells and decreased cell survival. Although NMDAR encephalitis with IgG antibodies is increasingly recognized and diagnosed, atypical presentations with NMDAR antibodies with immunoglobulin subclasses other than IgG pose a diagnostic and therapeutic challenge. Further clinical and neurobiological studies are needed to study the pathophysiological relevance of IgM NMDAR antibodies.


Subject(s)
Bipolar Disorder/diagnosis , Brain Diseases/immunology , Hashimoto Disease/immunology , Immunoglobulin M/immunology , Immunoglobulin M/pharmacology , Receptors, N-Methyl-D-Aspartate/immunology , Adult , Brain Diseases/physiopathology , Cell Death/drug effects , Cell Death/physiology , Encephalitis , Hashimoto Disease/physiopathology , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/physiopathology , Humans , Male , Neurons/drug effects , Neurons/metabolism , Neurons/physiology , Primary Cell Culture , Receptors, N-Methyl-D-Aspartate/metabolism
12.
Expert Opin Drug Saf ; 11(6): 1047-62, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22992213

ABSTRACT

INTRODUCTION: Despite the progress in antipsychotic treatment, modern antipsychotic medication is still associated with side effects, reduced compliance, drug discontinuation and insufficient effects on negative and cognitive symptoms. Sertindole is an antipsychotic compound, with high affinity for dopamine D(2), serotonin 5-HT(2A), 5-HT(2C) and α(1)-adrenergic receptors, which has been reintroduced in the market after extended re-evaluation of its safety and risk-benefit profile. AREAS COVERED: Sertindole's pharmacological profile, pharmacokinetics, neuophysiological properties, efficacy on positive, negative and cognitive symptoms and safety issues are covered in this article, based on a literature review from 1990 to 2012. EXPERT OPINION: Based on five double-blind, randomized, placebo-, haloperidol- or risperidone-controlled studies in patients with schizophrenia, sertindole shows a comparable efficacy with haloperidol and risperidone on positive symptoms, while the effect on negative symptoms seems to be superior. Sertindole is generally well tolerated, but is associated with a dose-related QTc interval prolongation (+22 ms). Risk factors for drug-induced arrhythmia, such as cardiac diseases, congenital long QT syndrome, prolongated QTc at baseline, etc. and drug interactions should be considered before prescribing sertindole. To minimize cardiovascular risk, regular ECG recording is required. Sertindole can be an important second-line option for the treatment of schizophrenia for patients intolerant to at least one other antipsychotic. Further comparison with other SGAs and investigations on subgroups (e.g., children, elderly, first-episode, treatment-refractory patients, etc.) are still needed for a precise understanding of the therapeutic benefits and its role in schizophrenia therapy.


Subject(s)
Antipsychotic Agents/therapeutic use , Imidazoles/therapeutic use , Indoles/therapeutic use , Schizophrenia/drug therapy , Animals , Antipsychotic Agents/adverse effects , Antipsychotic Agents/pharmacology , Cardiovascular Diseases/chemically induced , Cardiovascular Diseases/prevention & control , Dose-Response Relationship, Drug , Electrocardiography , Humans , Imidazoles/adverse effects , Imidazoles/pharmacology , Indoles/adverse effects , Indoles/pharmacology , Randomized Controlled Trials as Topic , Risk Factors , Schizophrenia/physiopathology
13.
J Psychiatr Res ; 45(5): 699-705, 2011 May.
Article in English | MEDLINE | ID: mdl-21067772

ABSTRACT

BACKGROUND: There is growing evidence of abnormalities of high-frequency oscillations in the gamma-range of the electroencephalography in schizophrenia. The generation of neural activity in the gamma-band was shown to be critically related to a glutamatergic and GABAergic microcircuit which is also known to be involved in the pathophysiology of schizophrenia. Recently, a reduction of the early auditory evoked gamma-band response (eGBR) in schizophrenic patients was reported. In order to investigate the possible applicability of this neurophysiological marker as an intermediate phenotype for schizophrenia, this is the main question of our investigation: Is the early eGBR decreased regarding evoked power and phase locking in first-degree relatives of patients with schizophrenia? METHODS: We investigated the early eGBR in 17 unaffected first-degree relatives of patients with schizophrenia and in age-, gender- and education-matched groups of schizophrenic patients and healthy controls using an auditory reaction task. RESULTS: First-degree relatives of patients with schizophrenia and schizophrenic patients showed a significant reduction of evoked power and phase locking of the early eGBR compared to healthy controls. CONCLUSION: This study shows significantly reduced evoked power and phase locking of the early auditory eGBR in first-degree relatives of patients with schizophrenia pointing to the applicability of this marker as a heritable intermediate phenotype for schizophrenia. The findings are in line with the hypothesis of a disturbed GABAergic interneural modulation of pyramidal cells in schizophrenia and findings of different schizophrenia risk genes associated with transmission at glutamatergic and GABAergic synapses.


Subject(s)
Evoked Potentials, Auditory/physiology , Family Health , Family , Schizophrenia/physiopathology , Schizophrenic Psychology , Acoustic Stimulation/methods , Adult , Analysis of Variance , Brain Mapping , Electroencephalography/methods , Female , Humans , Male , Middle Aged , Reaction Time/physiology , Schizophrenia/genetics , Time Factors , Young Adult
14.
J Psychiatr Res ; 42(9): 734-45, 2008 Jul.
Article in English | MEDLINE | ID: mdl-17826793

ABSTRACT

Alcohol-dependence is often associated with comorbid psychiatric symptoms. However, the results concerning the influence of these symptoms on cognitive functioning in alcoholism are still inconsistent. The aim of this study was to determine performance monitoring in healthy volunteers and alcohol-dependent patients, and to assess the influence of trait anxiety on these processes. Sixteen healthy volunteers and 16 detoxified alcohol-dependent patients completed an auditory go/nogo paradigm. Functional magnetic resonance imaging, event-related potentials and behavioral data were acquired simultaneously. The patients were classified by median split based on level of self-rated trait anxiety (state-trait anxiety inventory; STAI). The results showed no significant differences regarding inhibition-associated electrophysiological and behavioral responses between alcohol-dependent patients with high-trait anxiety scores and alcohol-addicts with low-STAI scores. However, the functional MRI data revealed elevated activations during the response inhibition task especially in the middle frontal gyrus (BA 6/9), the superior frontal gyrus (BA 6/8/9) and the right inferior frontal gyrus, as well as temporo-parietal brain regions in patients with high-trait anxiety compared to non-anxious alcohol-addicts. Patients and healthy controls showed comparable results with regard to neural and behavioral responses. These results suggest that inhibitory control capacities of alcohol-dependent patients are not consistent: alcohol-addicts with high-trait anxiety ratings showed elevated neural responses compared to patients without any comorbid psychiatric symptoms. This may indicate that comorbid psychiatric symptoms need to be considered when assessing brain responses in alcohol-dependent patients.


Subject(s)
Alcoholism/metabolism , Anxiety Disorders/metabolism , Anxiety Disorders/psychology , Brain/metabolism , Brain/physiopathology , Evoked Potentials/physiology , Oxygen/blood , Adult , Alcoholism/epidemiology , Alcoholism/rehabilitation , Anxiety Disorders/epidemiology , Electroencephalography , Humans , Inactivation, Metabolic , Magnetic Resonance Imaging , Male , Severity of Illness Index
15.
Clin EEG Neurosci ; 38(2): 89-95, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17515174

ABSTRACT

Anxiety disorders are highly prevalent in patients with alcohol use disorder. The purpose of the present study was to examine the neural correlates of behavioral inhibition in alcohol-dependent patients (ICD-10: F 10.2), and in healthy controls and to determine the influence of anxiety on these processes. Therefore, behavioral responses (reaction times; error rates) and event-related potentials of 16 patients with alcohol dependence syndrome and 16 age-and gender-matched healthy controls were recorded while the participants performed an auditory go/no-go task. The patient group was stratified according to their self-rated trait anxiety (STAI) with scores above and below median. We hypothesized that patients suffering from alcohol dependence would show reduced no-go P3 amplitudes involved in response inhibition compared to healthy subjects. In patients with alcoholism and high trait anxiety the decline of no-go P3 amplitudes was expected to be less distinct. The estimation of effect size based on the reaction times of patients with high and low anxiety ratings revealed a cohen's d of 0.61 indicating a small effect. High trait anxiety ratings were also associated with slightly enhanced no-go P3 amplitudes in central brain regions (Mean no-go P3 amplitude at Cz: 10.43 microV) compared to patients with low anxiety scores (Mean 8.98 microV). The effect size (cohen's d) revealed a small effect. Using the Mann-Whitney-U-test for independent samples of the comparison of high- and low-anxious patients, however, did not reveal any significant differences concerning no-go P3 amplitudes. Patients with alcohol use disorder and healthy controls did not differ significantly with regard to reaction time, error rate and no-go P3 amplitudes. This study suggests that no-go P3 amplitudes in patients with alcohol use disorder might be affected to some degree by habitual anxiety. The results emphasize the importance of monitoring trait anxiety in studies regarding cognitive functions in subjects with alcohol use disorder.


Subject(s)
Alcoholism/physiopathology , Anxiety/physiopathology , Auditory Cortex/physiopathology , Electroencephalography/methods , Evoked Potentials, Auditory , Neural Inhibition , Reaction Time , Adult , Alcoholism/complications , Anxiety/complications , Humans , Psychomotor Performance , Statistics as Topic
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