Effects of high-intensity interval training on sleep disturbances associated with posttraumatic stress disorder.

Sleep disturbances are common in individuals with posttraumatic stress disorder. Exercise interventions are a promising approach in the treatment of sleep disorders, but little is known about the efficacy of exercise interventions for sleep disturbances associated with posttraumatic stress disorder. A total of 40 individuals with posttraumatic stress disorder were randomized to six sessions of either high-intensity interval training or low-to-moderate-intensity training, administered within 12 days. Sleep quality was assessed over 24 days from baseline to post with the Pittsburgh Sleep Quality Index, a sleep log, and a waist-worn actigraphy. Analyses revealed that, regardless of group allocation, Pittsburgh Sleep Quality Index score improved significantly by 2.28 points for high-intensity interval training and 1.70 points for low-to-moderate-intensity training (d = 0.56 for high-intensity interval training; 0.49 for low-to-moderate-intensity training) over time, while there were no significant changes in any sleep log or actigraphy measure. Analysis of a subsample of those affected by clinically significant sleep disturbances (n = 24) revealed a significant time effect with no difference between exercise interventions: Pittsburgh Sleep Quality Index improved significantly by 2.65 points for high-intensity interval training and 2.89 points for low-to-moderate-intensity training (d = 0.53 for high-intensity interval training; 0.88 for low-to-moderate-intensity training), and actigraphy measure of wake after sleep onset was reduced significantly by 14.39 minutes for high-intensity interval training and 6.96 minutes for low-to-moderate-intensity training (d = 0.47 for high-intensity interval training; 0.11 for low-to-moderate-intensity training) from baseline to post. In our pilot study, we found an improvement in sleep quality from pre- to post-assessment. There were no significant differences between exercise groups. Further studies are needed to investigate whether the found time effects reflect the exercise intervention or unrelated factors.

What to think or how to think - is symptom reduction in posttraumatic symptomatology associated with change in posttraumatic cognitions or perseverative thinking? A latent change score model approach.

OBJECTIVE: Patients with posttraumatic stress disorder (PTSD) report changes in what they think of the world and themselves, referred to as posttraumatic cognitions, and changes in how they think, reflected in increased perseverative thinking. We investigated whether pre-post therapy changes in the two aspects of thinking were associated with pre-post therapy changes in posttraumatic symptom severity. METHOD: 219 d clinic patients with posttraumatic stress symptoms received trauma-focused psychotherapy with cognitive behavioral and metacognitive elements. The posttraumatic cognitions inventory (PTCI), the perseverative thinking questionnaire (PTQ), and the Davidson trauma scale (DTS) were applied at two occasions, pre- and post-therapy. Using latent change score models, we investigated whether change in PTCI and change in PTQ were associated with change in DTS and its subscales. We then compared the predictive value of PTQ and PTCI in joint models. RESULTS: When jointly modeled, change in overall DTS score was associated with change in both PTCI and PTQ. Concerning DTS subscales, reexperiencing and avoidance were significantly associated with change in PTCI, but not in PTQ. CONCLUSION: Results indicate that both aspects of cognition may be valuable targets of psychotherapy. A focus on posttraumatic cognitions might be called for in patients with severe reexperiencing and avoidance.

XUV-Initiated Dissociation Dynamics of Molecular Oxygen (O2).

We performed a time-resolved spectroscopy experiment on the dissociation of oxygen molecules after the interaction with intense extreme-ultraviolet (XUV) light from the free-electron laser in Hamburg at Deutsches Elektronen-Synchrotron. Using an XUV-pump/XUV-probe transient-absorption geometry with a split-and-delay unit, we observe the onset of electronic transitions in the O2+ cation near 50 eV photon energy, marking the end of the progression from a molecule to two isolated atoms. We observe two different time scales of 290 ± 53 and 180 ± 76 fs for the emergence of different ionic transitions, indicating different dissociation pathways taken by the departing oxygen atoms. With regard to the emerging opportunities of tuning the central frequencies of pump and probe pulses and of increasing the probe-pulse bandwidth, future pump-probe transient-absorption experiments are expected to provide a detailed view of the coupled nuclear and electronic dynamics during molecular dissociation.

Patterns of individual differences in fiber tract integrity of the face processing brain network support neurofunctional models.

Face cognition, the ability to perceive faces and interpret facial information, is a crucial skill in human social interactions. At the neurobiological level, several functionally specialized brain regions constitute a network of face processing. However, the evidence whether functional specialization within the face network is also reflected in the white matter structural connectivity patterns is yet limited. Based on imaging data from 1051 young healthy adult women and men, we investigated individual differences in the integrity of fibre tracts connecting face-processing regions relative to brain-general tract integrity. We analyzed individual tract-averaged fractional anisotropy (FA) values with structural equation modeling (SEM). Our results show that beyond the variance explained by a general factor indicating the quality of global tracts, the specificity of white matter integrity within the face network can be accounted for by additional factors. These factors correspond to the core and extended networks suggested in classic neuro-functional models of face processing. The right-hemisphere dominance, as commonly found in face cognition studies, is also reflected in this factorial structure. Overall, our results extend the structural brain substrate of the classic functional face processing system to the network of fibre tracts connecting these brain areas, and shed light on a structure-function correspondence from the perspective of individual differences.

Reconstruction and control of a time-dependent two-electron wave packet.

The concerted motion of two or more bound electrons governs atomic and molecular non-equilibrium processes including chemical reactions, and hence there is much interest in developing a detailed understanding of such electron dynamics in the quantum regime. However, there is no exact solution for the quantum three-body problem, and as a result even the minimal system of two active electrons and a nucleus is analytically intractable. This makes experimental measurements of the dynamics of two bound and correlated electrons, as found in the helium atom, an attractive prospect. However, although the motion of single active electrons and holes has been observed with attosecond time resolution, comparable experiments on two-electron motion have so far remained out of reach. Here we show that a correlated two-electron wave packet can be reconstructed from a 1.2-femtosecond quantum beat among low-lying doubly excited states in helium. The beat appears in attosecond transient-absorption spectra measured with unprecedentedly high spectral resolution and in the presence of an intensity-tunable visible laser field. We tune the coupling between the two low-lying quantum states by adjusting the visible laser intensity, and use the Fano resonance as a phase-sensitive quantum interferometer to achieve coherent control of the two correlated electrons. Given the excellent agreement with large-scale quantum-mechanical calculations for the helium atom, we anticipate that multidimensional spectroscopy experiments of the type we report here will provide benchmark data for testing fundamental few-body quantum dynamics theory in more complex systems. They might also provide a route to the site-specific measurement and control of metastable electronic transition states that are at the heart of fundamental chemical reactions.

Nonlinear Coherence Effects in Transient-Absorption Ion Spectroscopy with Stochastic Extreme-Ultraviolet Free-Electron Laser Pulses.

We demonstrate time-resolved nonlinear extreme-ultraviolet absorption spectroscopy on multiply charged ions, here applied to the doubly charged neon ion, driven by a phase-locked sequence of two intense free-electron laser pulses. Absorption signatures of resonance lines due to 2p-3d bound-bound transitions between the spin-orbit multiplets ^{3}P_{0,1,2} and ^{3}D_{1,2,3} of the transiently produced doubly charged Ne^{2+} ion are revealed, with time-dependent spectral changes over a time-delay range of (2.4±0.3) fs. Furthermore, we observe 10-meV-scale spectral shifts of these resonances owing to the ac Stark effect. We use a time-dependent quantum model to explain the observations by an enhanced coupling of the ionic quantum states with the partially coherent free-electron laser radiation when the phase-locked pump and probe pulses precisely overlap in time.

Strong-Field Extreme-Ultraviolet Dressing of Atomic Double Excitation.

We report on the experimental observation of a strong-field dressing of an autoionizing two-electron state in helium with intense extreme-ultraviolet laser pulses from a free-electron laser. The asymmetric Fano line shape of this transition is spectrally resolved, and we observe modifications of the resonance asymmetry structure for increasing free-electron-laser pulse energy on the order of few tens of Microjoules. A quantum-mechanical calculation of the time-dependent dipole response of this autoionizing state, driven by classical extreme-ultraviolet (XUV) electric fields, evidences strong-field-induced energy and phase shifts of the doubly excited state, which are extracted from the Fano line-shape asymmetry. The experimental results obtained at the Free-Electron Laser in Hamburg (FLASH) thus correspond to transient energy shifts on the order of a few meV, induced by strong XUV fields. These results open up a new way of performing nonperturbative XUV nonlinear optics for the light-matter interaction of resonant electronic transitions in atoms at short wavelengths.

Signatures and control of strong-field dynamics in a complex system.

Controlling chemical reactions by light, i.e., the selective making and breaking of chemical bonds in a desired way with strong-field lasers, is a long-held dream in science. An essential step toward achieving this goal is to understand the interactions of atomic and molecular systems with intense laser light. The main focus of experiments that were performed thus far was on quantum-state population changes. Phase-shaped laser pulses were used to control the population of final states, also, by making use of quantum interference of different pathways. However, the quantum-mechanical phase of these final states, governing the system's response and thus the subsequent temporal evolution and dynamics of the system, was not systematically analyzed. Here, we demonstrate a generalized phase-control concept for complex systems in the liquid phase. In this scheme, the intensity of a control laser pulse acts as a control knob to manipulate the quantum-mechanical phase evolution of excited states. This control manifests itself in the phase of the molecule's dipole response accessible via its absorption spectrum. As reported here, the shape of a broad molecular absorption band is significantly modified for laser pulse intensities ranging from the weak perturbative to the strong-field regime. This generalized phase-control concept provides a powerful tool to interpret and understand the strong-field dynamics and control of large molecules in external pulsed laser fields.

Time-resolved four-wave-mixing spectroscopy for inner-valence transitions.

Noncollinear four-wave-mixing (FWM) techniques at near-infrared (NIR), visible, and ultraviolet frequencies have been widely used to map vibrational and electronic couplings, typically in complex molecules. However, correlations between spatially localized inner-valence transitions among different sites of a molecule in the extreme ultraviolet (XUV) spectral range have not been observed yet. As an experimental step toward this goal, we perform time-resolved FWM spectroscopy with femtosecond NIR and attosecond XUV pulses. The first two pulses (XUV-NIR) coincide in time and act as coherent excitation fields, while the third pulse (NIR) acts as a probe. As a first application, we show how coupling dynamics between odd- and even-parity, inner-valence excited states of neon can be revealed using a two-dimensional spectral representation. Experimentally obtained results are found to be in good agreement with ab initio time-dependent R-matrix calculations providing the full description of multielectron interactions, as well as few-level model simulations. Future applications of this method also include site-specific probing of electronic processes in molecules.

Temporal resolution beyond the average pulse duration in shaped noisy-pulse transient absorption spectroscopy.

In time-resolved spectroscopy, it is a widespread belief that the temporal resolution is determined by the laser pulse duration. Recently, it was observed and shown that partially coherent laser pulses as they are provided by free-electron-laser (FEL) sources offer an alternative route to reach a temporal resolution below the average pulse duration. Here, we demonstrate the generation of partially coherent light in the laboratory like we observe it at FELs. We present the successful implementation of such statistically fluctuating pulses by using the pulse-shaping technique. These pulses exhibit an average pulse duration about 10 times larger than their bandwidth limit. The shaped pulses are then applied to transient-absorption measurements in the dye IR144. Despite the noisy characteristics of the laser pulses, features in the measured absorption spectra occurring on time scales much faster than the average pulse duration are resolved, thus proving the universality of the described noisy-pulse concept.

Phase Reconstruction of Strong-Field Excited Systems by Transient-Absorption Spectroscopy.

The evolution of a V-type three-level system is studied, whose two resonances are coherently excited and coupled by two ultrashort laser pump and probe pulses, separated by a varying time delay. We relate the quantum dynamics of the excited multilevel system to the absorption spectrum of the transmitted probe pulse. In particular, by analyzing the quantum evolution of the system, we interpret how atomic phases are differently encoded in the time-delay-dependent spectral absorption profiles when the pump pulse either precedes or follows the probe pulse. This scheme is experimentally applied to atomic Rb, whose fine-structure-split 5s (2)S{1/2}→5p(2)P{1/2} and 5s(2)S_{1/2}→5p(2)P{3/2} transitions are driven by the combined action of a pump pulse of variable intensity and a delayed probe pulse. The provided understanding of the relationship between quantum phases and absorption spectra represents an important step towards full time-dependent phase reconstruction (quantum holography) of bound-state wave packets in strong-field light-matter interactions with atoms, molecules, and solids.

Extracting phase and amplitude modifications of laser-coupled Fano resonances.

Fano line shapes observed in absorption spectra encode information on the amplitude and phase of the optical dipole response. A change in the Fano line shape, e.g., by interaction with short-pulsed laser fields, allows us to extract dynamical modifications of the amplitude and phase of the coupled excited quantum states. We introduce and apply this physical mechanism to near-resonantly coupled doubly excited states in helium. This general approach provides a physical understanding of the laser-induced spectral shift of absorption-line maxima on a sub-laser-cycle time scale as they are ubiquitously observed in attosecond transient-absorption measurements.

Passively phase-stable, monolithic, all-reflective two-dimensional electronic spectroscopy based on a four-quadrant mirror.

A design for a passively phase-stable two-dimensional electronic spectroscopy experiment, based on a four-quadrant mirror concept, is introduced. The setup, which is particularly simple and robust, achieves subwavelength stability without the need for active stabilization or diffractive optical elements. Since only reflective optical components are used, the setup is suitable for few-cycle laser pulses and ultrabroad-bandwidth light in the ultraviolet, visible, and near-IR regions, with the capability to be used under grazing incidence for soft x ray or x-ray light at free-electron lasers.

The Affect Intolerance Scale (AIS), German version: A validation study in a student and clinical sample of patients with trauma-related disorders.

BACKGROUND AND OBJECTIVES: The Affect Intolerance Scale (AIS) assesses two core concepts of emotion regulation: appraisals of negative emotions as threatening and proneness to emotional avoidance. Maladaptive emotion regulation is associated with various psychopathologies. We translated and validated the AIS in a German student and clinical sample of patients with trauma-related disorders. METHODS: 340 patients, 161 with post-traumatic stress disorder and 179 with adjustment disorder, and 322 students were enrolled. We employed exploratory and confirmatory factor analyses in a cross-validation design to investigate construct validity, convergent and discriminant validity, and reliability. RESULTS: We replicated the originally described two-factor structure in both samples. Cronbach's α was 0.947 in the student and 0.950 in the clinical sample. AIS subscales showed moderate to high correlations with convergent and low correlations with discriminant measures. AIS total scores were significantly larger in the clinical sample, controlled for gender and age. LIMITATIONS: This study provides a unified cross-validation model in a clinical and a student sample at the cost of reduced sample sizes. CONCLUSIONS: The AIS is a valid measure of affect intolerance with the discriminative ability to distinguish between patients with trauma-related disorders and students. Test redundancy within both sub-constructs of the AIS might lead to biased estimates but allows for increased test precision, rendering the AIS a tool suitable for individual treatment monitoring.

Boosting the Theory of Mind Network: Specific Psychotherapy Increases Neural Correlates of Affective Theory of Mind in Euthymic Bipolar Disorder.

BACKGROUND: In bipolar disorder, impaired affective theory of mind (aToM) performance and aberrant neural activation in the ToM brain network partly explain social functioning impairments. However, it is not yet known whether psychotherapy of bipolar disorder influences neuroimaging markers of aToM. METHODS: In this study, conducted within the multicentric randomized controlled trial of the BipoLife consortium, patients with euthymic bipolar disorder underwent 2 group interventions over 6 months (mean = 28.45 weeks): 1) a specific, cognitive behavioral intervention (specific psychotherapeutic intervention [SEKT]) (n = 31) targeting impulse regulation, ToM, and social skills and 2) an emotion-focused intervention (FEST) (n = 28). To compare the effect of SEKT and FEST on neural correlates of aToM, patients performed an aToM task during functional magnetic resonance imaging before and after interventions (final functional magnetic resonance imaging sample of pre- and postcompleters, SEKT: n = 16; FEST: n = 17). Healthy control subjects (n = 32) were scanned twice with the same time interval. Because ToM was trained in SEKT, we expected an increased ToM network activation in SEKT relative to FEST postintervention. RESULTS: Both treatments effectively stabilized patients' euthymic state in terms of affective symptoms, life satisfaction, and global functioning. Confirming our expectations, SEKT patients showed increased neural activation within regions of the ToM network, bilateral temporoparietal junction, posterior cingulate cortex, and precuneus, whereas FEST patients did not. CONCLUSIONS: The stabilizing effect of SEKT on clinical outcomes went along with increased neural activation of the ToM network, while FEST possibly exerted its positive effect by other, yet unexplored routes.

Daring to Feel: Emotion-Focused Psychotherapy Increases Amygdala Activation and Connectivity in Euthymic Bipolar Disorder-A Randomized Controlled Trial.

BACKGROUND: In bipolar disorder (BD), the alternation of extreme mood states indicates deficits in emotion processing, accompanied by aberrant neural function of the emotion network. The present study investigated the effects of an emotion-centered psychotherapeutic intervention on amygdala responsivity and connectivity during emotional face processing in BD. METHODS: In a randomized controlled trial within the multicentric BipoLife project, euthymic patients with BD received one of two interventions over 6 months: an unstructured, emotion-focused intervention (FEST), where patients were guided to adequately perceive and label their emotions (n = 28), or a specific, structured, cognitive behavioral intervention (SEKT) (n = 31). Before and after interventions, functional magnetic resonance imaging was conducted while patients completed an emotional face-matching paradigm (final functional magnetic resonance imaging sample of patients completing both measurements: SEKT, n = 17; FEST, n = 17). Healthy control subjects (n = 32) were scanned twice after the same interval without receiving any intervention. Given the focus of FEST on emotion processing, we expected FEST to strengthen amygdala activation and connectivity. RESULTS: Clinically, both interventions stabilized patients' euthymic states in terms of affective symptoms. At the neural level, FEST versus SEKT increased amygdala activation and amygdala-insula connectivity at postintervention relative to preintervention time point. In FEST, the increase in amygdala activation was associated with fewer depressive symptoms (r = 0.72) 6 months after intervention. CONCLUSIONS: Enhanced activation and functional connectivity of the amygdala after FEST versus SEKT may represent a neural marker of improved emotion processing, supporting the FEST intervention as an effective tool in relapse prevention in patients with BD.

Noisy optical pulses enhance the temporal resolution of pump-probe spectroscopy.

Time-resolved measurements of quantum dynamics are based on the availability of controlled events that are shorter than the typical evolution time scale of the processes to be observed. Here we introduce the concept of noise-enhanced pump-probe spectroscopy, allowing the measurement of dynamics significantly shorter than the average pulse duration by exploiting randomly varying, partially coherent light fields consisting of bunched colored noise. These fields are shown to be superior by more than a factor of 10 to frequency-stabilized fields, with important implications for time-resolved experiments at x-ray free-electron lasers and, in general, for measurements at the frontiers of temporal resolution (e.g., attosecond spectroscopy). As an example application, the concept is used to explain the recent experimental observation of vibrational wave-packet motion in D(2)(+) on time scales shorter than the average pulse duration.

Reflections and New Perspectives on Face Cognition as a Specific Socio-Cognitive Ability.

The study of socio-cognitive abilities emerged from intelligence research, and their specificity remains controversial until today. In recent years, the psychometric structure of face cognition (FC)-a basic facet of socio-cognitive abilities-was extensively studied. In this review, we summarize and discuss the divergent psychometric structures of FC in easy and difficult tasks. While accuracy in difficult tasks was consistently shown to be face-specific, the evidence for easy tasks was inconsistent. The structure of response speed in easy tasks was mostly-but not always-unitary across object categories, including faces. Here, we compare studies to identify characteristics leading to face specificity in easy tasks. The following pattern emerges: in easy tasks, face specificity is found when modeling speed in a single task; however, when modeling speed across multiple, different easy tasks, only a unitary factor structure is reported. In difficult tasks, however, face specificity occurs in both single task approaches and task batteries. This suggests different cognitive mechanisms behind face specificity in easy and difficult tasks. In easy tasks, face specificity relies on isolated cognitive sub-processes such as face identity recognition. In difficult tasks, face-specific and task-independent cognitive processes are employed. We propose a descriptive model and argue for FC to be integrated into common taxonomies of intelligence.

Mechanisms of face specificity - Differentiating speed and accuracy in face cognition by event-related potentials of central processing.

Given the crucial role of face recognition in social life, it is hardly surprising that cognitive processes specific for faces have been identified. In previous individual differences studies, the speed (measured in easy tasks) and accuracy (difficult tasks) of face cognition (FC, involving perception and recognition of faces) have been shown to form distinct abilities, going along with divergent factorial structures. This result has been replicated, but remained unexplained. To fill this gap, we first parameterized the sub-processes underlying speed vs. accuracy in easy and difficult memory tasks for faces and houses in a large sample. Then, we analyzed event-related potentials (ERPs) extracted from the EEG by using residue iteration decomposition (RIDE), yielding a central (C) component that is comparable to a purified P300. Structural equation modeling (SEM) was applied to estimate face specificity of C component latencies and amplitudes. If performance in easy tasks relies on purely general processes that are insensitive to stimulus content, there should be no specificity of individual differences in the latency recorded in easy tasks. However, in difficult tasks specificity was expected. Results indicated that, contrary to our predictions, specificity occurred in the C component latency of both speed-based and accuracy-based measures, but was stronger in accuracy. Further analyses suggested specific relationships between the face-related C latency and FC ability. Finally, we detected specificity in RTs of easy tasks when single tasks were modeled, but not when multiple tasks were jointly modeled. This suggests that the mechanisms leading to face specificity in performance speed are distinct across tasks.

Perceiving faces: Too much, too fast?-face specificity in response caution.

Faces are a major source of information in social interaction. The ability to perceive and interpret faces thus carries paramount importance in people's social lives. However, this crucial ability is not yet fully understood. Individual differences studies show that the speed and accuracy of face cognition (including perception and memory/recognition), the two facets targeted when measuring cognitive performance, are relatively independent traits. Unlike accuracy data, individual differences in reaction times (RTs) measured in perceptual decision tasks with or without memory load using faces and objects, do not show face-specific variance. Here, we applied the diffusion model to RT and accuracy data captured by simple perceptual decision tasks to improve understanding of the lack of face specificity. If performance speed in face cognition tasks is truly a global, nonspecific individual ability, no parameter of the diffusion model should hold face specificity. In a study on adults (N = 217), we administered two tasks of face and object perception. We used individually estimated diffusion model parameters as manifest variables to study face specificity in drift rate (ν), boundary separation (a), and nondecision time (Ter) using structural equation modeling. Furthermore, to study differential relationships between diffusion model parameters and measures of cognitive abilities, we regressed factors of face and object cognition accuracy on factors of diffusion model parameters. The results revealed face specificity only in boundary separation. This suggests face-specific adjustment in the cautiousness of information processing. (PsycINFO Database Record (c) 2018 APA, all rights reserved).