The research landscape of bipolar disorder in Germany: productive, but underfunded.

Background: The recurrent mental illness bipolar disorder is a major burden on the healthcare system, which underlines the importance of research into this disease. Germany is one of the most productive countries in this research activity. This bibliometric analysis aims to outline the social and conceptual structure of the German research landscape on bipolar disorder over the last decade.

Individual differences in resilience to stress are associated with affective flexibility.

Cognitive flexibility is frequently linked to resilience because of its important contribution to stress regulation. In this context, particularly affective flexibility, defined as the ability to flexibly attend and disengage from affective information, may play a significant role. In the present study, the relationship of cognitive and affective flexibility and resilience was examined in 100 healthy participants.

Neural correlates of affective task switching and asymmetric affective task switching costs.

The control of emotions is of potentially great clinical relevance. Accordingly, there has been increasing interest in understanding the cognitive mechanisms underlying the ability to switch efficiently between the processing of affective and non-affective information. Reports of asymmetrically increased switch costs when switching toward the more salient emotion task indicate specific demands in the flexible control of emotion.

Internal consistency and test-retest reliability of an affective task-switching paradigm.

Affective flexibility refers to the flexible adaptation of behavior or thought given emotionally relevant stimuli, tasks, or contexts, and has been associated with the efficiency of emotion regulation and dealing with stress and adversity. Experimentally, individual differences in affective flexibility have been measured as behavioral costs (response times, errors rates) of switching between affective and neutral tasks. However, behavioral task measures can only be treated as trait-like characteristics if they have sufficient psychometric quality.

Cognitive, Affective, and Feedback-Based Flexibility - Disentangling Shared and Different Aspects of Three Facets of Psychological Flexibility.

Cognitive flexibility - the ability to adjust one ´s behavior to changing environmental demands - is crucial for controlled behavior. However, the term 'cognitive flexibility' is used heterogeneously, and associations between cognitive flexibility and other facets of flexible behavior have only rarely been studied systematically. To resolve some of these conceptual uncertainties, we directly compared cognitive flexibility (cue-instructed switching between two affectively neutral tasks), affective flexibility (switching between a neutral and an affective task using emotional stimuli), and feedback-based flexibility (non-cued, feedback-dependent switching between two neutral tasks).

Acetylcholine modulates human working memory and subsequent familiarity based recognition via alpha oscillations.

Working memory (WM) can be defined as the ability to maintain and process physically absent information for a short period of time. This vital cognitive function has been related to cholinergic neuromodulation and, in independent work, to theta (4-8Hz) and alpha (9-14Hz) band oscillations. However, the relationship between both aspects remains unclear.

Structural and functional hallmarks of amyotrophic lateral sclerosis progression in motor- and memory-related brain regions.

Previous studies have shown that in amyotrophic lateral sclerosis (ALS) multiple motor and extra-motor regions display structural and functional alterations. However, their temporal dynamics during disease-progression are unknown. To address this question we employed a longitudinal design assessing motor- and novelty-related brain activity in two fMRI sessions separated by a 3-month interval.

Dopaminergic stimulation facilitates working memory and differentially affects prefrontal low theta oscillations.

We used electroencephalography (EEG) together with psychopharmacological stimulation to investigate the role of dopamine in neural oscillations during working memory (WM). Following a within-subjects design, healthy humans either received the dopamine precursor L-Dopa (150 mg) or a placebo before they performed a Sternberg WM paradigm. Here, sequences of sample images had to be memorized for a delay of 5 s in three different load conditions (two, four or six items).

Motor phenotype and magnetic resonance measures of basal ganglia iron levels in Parkinson's disease.

Background: In Parkinson's disease the degree of motor impairment can be classified with respect to tremor dominant and akinetic rigid features. While tremor dominance and akinetic rigidity might represent two ends of a continuum rather than discrete entities, it would be important to have non-invasive markers of any biological differences between them in vivo, to assess disease trajectories and response to treatment, as well as providing insights into the underlying mechanisms contributing to heterogeneity within the Parkinson's disease population.

Methods: Here, we used magnetic resonance imaging to examine whether Parkinson's disease patients exhibit structural changes within the basal ganglia that might relate to motor phenotype.

Dopamine modulates processing speed in the human mesolimbic system.

Neural activity in mesolimbic brain regions scales with stimulus novelty but the mechanistic role of neurotransmitters in this process remains unclear. Here, we used magnetoencephalography together with psychopharmacological stimulation in healthy humans to demonstrate that the neuronal dynamics of novelty processing are temporally adaptive and flexible. In particular, enhanced dopaminergic (150mg levodopa) - but not cholinergic (8mg galantamine) - neurotransmission accelerated the onset of novelty signals within the medial temporal lobe (MTL) from ~300 to <100ms.

Magnetic resonance volumetry and spectroscopy of hippocampus and insula in relation to severe exposure of traumatic stress.

Severe and chronic stress affects the hippocampus, especially during development. However, studies concerning structural alterations of the hippocampus yielded a rather inconsistent picture. Moreover, further anxiety-relevant brain regions, such as the insula, might be implicated in the pathophysiology of posttraumatic stress disorder (PTSD).

Structural alterations in lateral prefrontal, parietal and posterior midline regions of men with chronic posttraumatic stress disorder.

Background: So far, the neural network associated with posttraumatic stress disorder (PTSD) has been suggested to mainly involve the amygdala, hippocampus and medial prefrontal cortex. However, increasing evidence indicates that cortical regions extending beyond this network might also be implicated in the pathophysiology of PTSD. We aimed to investigate PTSD-related structural alterations in some of these regions.

Association study of trauma load and SLC6A4 promoter polymorphism in posttraumatic stress disorder: evidence from survivors of the Rwandan genocide.

Objective: As exposure to different types of traumatic stressors increases, the occurrence of posttraumatic stress disorder (PTSD) increases. However, because some people exhibit either surprising resilience or high vulnerability, further influencing factors have been conjectured, such as gene-environment interactions. The SLC6A4 gene, which encodes serotonin transporter, has been identified as predisposing toward differential emotional processing between genotypes of its promoter polymorphism.

No PTSD-related differences in diurnal cortisol profiles of genocide survivors.

Posttraumatic stress disorder (PTSD) has been associated with reduced cortisol levels. Opposing results have been interpreted as resulting from methodological differences between studies. We investigated the diurnal profile of salivary cortisol in a population of highly traumatized adult males from Rwanda with and without PTSD, who spent the whole day of examination together under a maximally standardized schedule.

Lack of cortisol response in patients with posttraumatic stress disorder (PTSD) undergoing a diagnostic interview.

Background: According to DSM-IV, the diagnosis of posttraumatic stress disorder (PTSD) requires the experience of a traumatic event during which the person's response involved intense fear, helplessness, or horror. In order to diagnose PTSD, clinicians must interview the person in depth about his/her previous experiences and determine whether the individual has been traumatized by a specific event or events. However, asking questions about traumatic experiences can be stressful for the traumatized individual and it has been cautioned that subsequent "re-traumatization" could occur.