A5065725115- Functional Brain Connectivity Studies
- Advanced MRI Techniques and Applications
- Medical Imaging Techniques and Applications
- Treatment of Major Depression
- Transcranial Magnetic Stimulation Studies
- Neural and Behavioral Psychology Studies
- Neuroscience and Neuropharmacology Research
- Neural dynamics and brain function
- Neurotransmitter Receptor Influence on Behavior
- Advanced Neuroimaging Techniques and Applications
- Epilepsy research and treatment
- Memory and Neural Mechanisms
- Mental Health Research Topics
- Stress Responses and Cortisol
- Bioinformatics and Genomic Networks
- Cardiac Imaging and Diagnostics
- EEG and Brain-Computer Interfaces
- Diet and metabolism studies
- Adipose Tissue and Metabolism
- Pharmacological Effects and Toxicity Studies
- Neuroinflammation and Neurodegeneration Mechanisms
- Computational Drug Discovery Methods
- Biochemical effects in animals
- Mitochondrial Function and Pathology
- Receptor Mechanisms and Signaling
Medical University of Vienna
2016-2025
Center for Neurosciences
2025
Comprehensive Cancer Center Vienna
2025
Hong Kong Polytechnic University
2023
Universitätszahnklinik Wien
2016
Background Electroconvulsive therapy (ECT) is the treatment of choice for severe mental illness including treatment-resistant depression (TRD). Increases in volume hippocampus and amygdala following ECT have consistently been reported. Aims To investigate neuroplastic changes after specific hippocampal subfields nuclei using high-resolution structural magnetic resonance imaging (MRI) (trial registration: clinicaltrials.gov – NCT02379767). Method MRI scans were carried out 14 patients (11...
The ability to solve cognitive tasks depends upon adaptive changes in the organization of whole-brain functional networks. However, link between task-induced network reconfigurations and their underlying energy demands is poorly understood. We address this by multimodal analyses integrating molecular neuroimaging acquired concurrently during a complex task. Task engagement elicited marked increase association glucose consumption brain reorganization. This convergence metabolic neural...
The nervous and circulatory system interconnects the various organs of human body, building hierarchically organized subsystems, enabling fine-tuned, metabolically expensive brain-body inter-organ crosstalk to appropriately adapt internal external demands. A deviation or failure in function a single organ subsystem could trigger unforeseen biases dysfunctions entire network, leading maladaptive physiological psychological responses. Therefore, quantifying these networks healthy individuals...
External tasks evoke characteristic fMRI BOLD signal deactivations in the default mode network (DMN). However, for corresponding metabolic glucose demands both decreases and increases have been reported. To resolve this discrepancy, functional PET/MRI data from 50 healthy subjects performing Tetris were combined with previously published sets of working memory, visual motor stimulation. We show that metabolism posteromedial DMN is dependent on correspondingly engaged task-positive networks....
Previous studies suggest that transcranial magnetic stimulation exerts antidepressant effects by altering functional connectivity (FC). However, knowledge about this mechanism is still limited. Here, we aimed to investigate the effect of bilateral sequential theta-burst (TBS) on FC in treatment-resistant depression (TRD) a sham-controlled longitudinal study. TRD patients (n = 20) underwent three-week treatment intermittent TBS left and continuous right dorsolateral prefrontal cortex (DLPFC)....
The assessment of dopamine release with the PET competition model is thoroughly validated but entails disadvantages for investigation cognitive processes. We introduce a novel approach incorporating 6-[ 18 F]FDOPA uptake as index dynamic regulation synthesis enzymes by neuronal firing. feasibility this demonstrated assessing widely described sex differences in neurotransmission. Reward processing was behaviorally investigated 36 healthy participants, whom 16 completed fPET and fMRI during...
Positron emission tomography (PET) provides precise molecular information on physiological processes, but its low temporal resolution is a major obstacle. Consequently, we characterized the metabolic response of human brain to working memory performance using an optimized functional PET (fPET) framework at 3 s.
Abstract Purpose Functional PET (fPET) is a novel technique for studying dynamic changes in brain metabolism and neurotransmitter signaling. Accurate quantification of fPET relies on measuring the arterial input function (AIF), traditionally achieved through invasive blood sampling. While non-invasive image-derived functions (IDIF) offer an alternative, they suffer from limited spatial resolution field view. To overcome these issues, we developed validated scan protocol utilizing cardiac...
Abstract Functional Positron Emission Tomography (fPET) has advanced as an effective tool for investigating dynamic processes in glucose metabolism and neurotransmitter action, offering potential insights into brain function, disease progression, treatment development. Despite significant methodological advances, extracting stimulation-specific information presents additional challenges optimizing signal processing across both spatial temporal domains, which are essential obtaining...
Mapping the neuronal response during cognitive processing is of crucial importance to gain new insights into human brain function. BOLD imaging and ASL are established MRI methods in this endeavor. Recently, novel approach functional PET (fPET) was introduced, enabling absolute quantification glucose metabolism at rest task execution a single measurement. Here, we report test-retest reliability fPET direct comparison ASL. Twenty healthy subjects underwent two PET/MRI measurements, providing...
With their ability to cross the blood-brain barrier, transport and regulate release of various signaling molecules, extracellular vesicles (EVs) constitute a novel avenue study intercellular communication in pathologies, including psychiatric disorders. We studied 34 major depressive disorder (MDD) patients 57 healthy controls characterized EVs isolated from plasma using digital holographic tomography (DHT) nanoparticle tracking analysis (NTA). detected DHT were markedly smaller less...
Abstract Background The assessment of dynamic changes in the cerebral glucose metabolism through a single PET scan holds significant promise for advancing our knowledge brain function both health and disease. Unlike fMRI, functional positron emission tomography (fPET) using [18F] Fludeoxyglucose ([18F]FDG) offers measure neuronal activity independent neurovascular coupling [1,2]. However, necessity an arterial input poses challenges, as it can be unpleasant participants also increases...
Abstract Background Previous studies have reported spatial dissociations between glucose metabolism and BOLD responses in the human posterior cingulate cortex (PCC)1, with an opposite influence of fronto-parietal network (FPN) dorsal attention (DAN) onto PCC2. Until recently, a truly synchronized assessment these influences temporal domain was limited due to inherently low resolution positron emission tomography (PET) when compared functional magnetic resonance imaging (fMRI). Aims &...
Abstract Background The monetary incentive delay (MID) task has been regularly used to assess reward and punishment processing, especially in combination with functional magnetic resonance imaging (fMRI) [1].Previous work by our group proposed 6-[18F]-fluoro-l-dopa (6-[18F]FDOPA) uptake as indicator of dopamine synthesis its regulation neuronal firing [2]. Simultaneous measurement PET (fPET) MRI parameters, performed via a combined PET/MR scanner, allows for even more robust investigation...
Abstract Background Extracellular vesicles (EVs) play a crucial role in facilitating intercellular communication. Their capacity to traverse the blood-brain barrier, transport, and control release of diverse neurotransmitters underscores their potential involvement pathophysiology psychiatric disorders (1). The small size biogenesis EVs complicates detection investigation (2). However, exosomal markers, including CD63 CD9, may provide convenient method for major depressive disorder (MDD)....
Abstract Background Selective serotonin reuptake inhibitors (SSRIs) target the transporter (SERT) and constitute first line of pharmacological treatment major depressive disorder (MDD). SSRIs also affect emotion processing brain function in healthy individuals (1-4). Previous studies found increased amygdala activation after intake SSRI citalopram related during negative emotions to SERT availability (5, 6). Furthermore, imaging genetics reported an influence SERT-linked promotor region...
Abstract Background Reward processing is implicated in everyday functioning and several psychiatric conditions including major depressive disorder. The monetary incentive delay (MID) task functional magnetic resonance imaging (fMRI) are widely used to study the neural basis of reward punishment humans (1). However, commonly employed BOLD signal mainly represents glutamate-mediated changes cerebral blood flow, volume oxygenation rather than modulatory neurotransmitter action. As recently...
[18F]FDG positron emission tomography (PET) is extensively utilized to assess brain glucose metabolism, typically through static images reflecting radiotracer accumulation of up one hour. In comparison, functional PET (fPET) enables investigation dynamics occuring within seconds. However, the physiological mechanisms supporting these rapid changes in metabolism necessitate further attention allow accurate interpretation function and their clinical implications. This work highlights candidate...
Functional Positron Emission Tomography (fPET) is an effective tool for studying dynamic processes in glucose metabolism and neurotransmitter action, providing insights into brain function disease progression. However, optimizing signal processing to extract stimulation-specific information remains challenging. This study systematically evaluates state-of-the-art filtering techniques fPET imaging. Forty healthy participants performed a cognitive task (Tetris®) during [ 18 F]FDG PET/MR scans....
Impaired cognitive flexibility represents a widespread symptom in psychiatric disorders, including major depressive disorder (MDD), disease, characterized by an imbalance of neurotransmitter concentrations. While memory formation is mostly associated with glutamate, also gamma-Aminobutyric acid (GABA) and serotonin show attributions complex interplay between systems. Treatment selective reuptake inhibitors (SSRIs) does not solely affect the serotonergic system but shows downstream effects on...
Animal studies using selective serotonin reuptake inhibitors (SSRIs) and learning paradigms have demonstrated that is important for flexibility in executive functions learning. SSRIs might facilitate relearning through neuroplastic processes thus exert their clinical effects psychiatric diseases where cognitive functioning affected. However, translation of these mechanisms to humans missing. In this randomized placebo-controlled trial, we assessed functional brain activation during memory...
Abstract The neurobiological basis of learning is reflected in adaptations brain structure, network organization and energy metabolism. However, it still unknown how different neuroplastic mechanisms act together if cognitive advancements relate to general or task-specific changes. Therefore, we tested hierarchical interactions contribute improvements the performance a visuo-spatial processing task by employing simultaneous PET/MR neuroimaging before after 4-week period. We combined...
Introduction: Dynamic positron emission tomography (PET) and the application of kinetic models can provide important quantitative information based on its temporal information. This however requires arterial blood sampling, which be challenging to acquire. Nowadays, state-of-the-art PET/CT systems offer fully automated, whole-body (WB) modelling protocols using image-derived input functions (IDIF) replace sampling. Here, we compared validity an automatic WB model protocol reference standard...