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Dive into the research topics where Julia Zeller is active.

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Featured researches published by Julia Zeller.


American Journal of Geriatric Psychiatry | 2010

Altered Parietal Brain Oxygenation in Alzheimer's Disease as Assessed With Near-Infrared Spectroscopy

Julia Zeller; Martin J. Herrmann; A.-C. Ehlis; Thomas Polak; Andreas J. Fallgatter

OBJECTIVE Visuospatial deficits are among the first symptoms of Alzheimer disease (AD) and linked to lower activation in the superior parietal cortex as assessed with functional imaging. Near-infrared spectroscopy (NIRS) is an optical method to measure changes in the concentration of oxygenated hemoglobin and deoxygenated hemoglobin in the microvascular system of the cortex. Because of its advantages in measurement situation, NIRS has proven to be especially suited for investigating psychiatric patients. The aim of this study was to probe the activation of parietal regions in patients with AD, performing a visuospatial task by means of functional NIRS (fNIRS). METHODS Thirteen patients with suspected mild AD and 13 healthy subjects comparable in age and gender were investigated while working on a modified version of the Benton Line Orientation Task. RESULTS During the spatial task, healthy subjects showed explicit parietal activation, whereas patients displayed only activation during the control task. Interestingly, there was no difference in visuospatial performance between the two groups. CONCLUSION The results indicate that fNIRS is able to measure parietal activation deficits in patients with AD, which could be developed into an early detection method in the future.


Neuropsychologia | 2014

Neural correlates of a standardized version of the trail making test in young and elderly adults: a functional near-infrared spectroscopy study.

Laura D. Müller; Anne Guhn; Julia Zeller; Stefanie C. Biehl; Thomas Dresler; Tim Hahn; Andreas J. Fallgatter; Thomas Polak; Jürgen Deckert; Martin J. Herrmann

The trail making test (TMT) is a widely applied diagnostic tool measuring executive functioning in order to discriminate between healthy and pathological aging processes. However, due to its paper-and-pencil nature it is difficult to adapt for functional brain imaging. Related neural underpinnings even in healthy aging are mostly unknown since no consistent administration for imaging is available. In this study a standardized implementation of the TMT for functional near-infrared spectroscopy (fNIRS) is proposed to investigate associated frontal cortex activation in healthy young (mean age 25.7 ± 3.02 years) and elderly adults (mean age 70.95 ± 3.55 years). The TMT consisted of a number condition (TMT-A), an alternating number and letter condition (TMT-B) as well as a control task. Behavioral results demonstrated that elderly participants performed slower but committed a similar number of errors compared to younger adults. The fNIRS results showed that particularly the TMT-B provoked bilateral activation in the ventro- and dorsolateral prefrontal cortex (vlPFC and dlPFC) as well as in premotor regions. Elderly participants displayed more significantly activated channels and a different activation pattern compared to younger participants especially manifesting in more bilateral dlPFC activation. In line with the hemispheric asymmetry reduction in elderly adults (HAROLD) model, the results were interpreted as an additional need for cognitive control resources in elderly participants. This study succeeded in implementing an appropriate version of the TMT for fNIRS and helps elucidating neural aging effects associated with this task.


BMC Neurology | 2015

Increased cortical activation upon painful stimulation in fibromyalgia syndrome

Nurcan Üçeyler; Julia Zeller; Susanne Kewenig; Sarah Kittel-Schneider; Andreas J. Fallgatter; Claudia Sommer

BackgroundFibromyalgia syndrome (FMS) is a chronic condition characterized by widespread pain and associated symptoms. We investigated cerebral activation in FMS patients by functional near-infrared spectroscopy (fNIRS).MethodsTwo stimulation paradigms were applied: a) painful pressure stimulation at the dorsal forearm; b) verbal fluency test (VFT). We prospectively recruited 25 FMS patients, ten patients with unipolar major depression (MD) without pain, and 35 healthy controls. All patients underwent neurological examination and all subjects were investigated with questionnaires (pain, depression, FMS, empathy).ResultsFMS patients had lower pressure pain thresholds than patients with MD and controls (p < 0.001) and reported higher pain intensity (p < 0.001). Upon unilateral pressure pain stimulation fNIRS recordings revealed increased bilateral cortical activation in FMS patients compared to controls (p < 0.05). FMS patients also displayed a stronger contralateral activity over the dorsolateral prefrontal cortex in direct comparison to patients with MD (p < 0.05). While all three groups performed equally well in the VFT, a frontal deficit in cortical activation was only found in patients with depression (p < 0.05). Performance and cortical activation correlated negatively in FMS patients (p < 0.05) and positively in patients with MD (p < 0.05).ConclusionOur data give further evidence for altered central nervous processing in patients with FMS and the distinction between FMS and MD.Trial registrationISRCTN registry ID ISRCTN15015327 (24.09.2015).


European Archives of Psychiatry and Clinical Neuroscience | 2014

Vagus somatosensory evoked potentials are delayed in Alzheimer’s disease, but not in major depression

Thomas Polak; Thomas Dresler; Julia Zeller; Bodo Warrings; Peter Scheuerpflug; Andreas J. Fallgatter; Jürgen Deckert; Florian Metzger

In Alzheimer’s disease (AD), the degeneration of brainstem nuclei is different from major depression (MD). Thus, vagus somatosensory evoked potentials (VSEP) proposed for the functional assessment of brainstem nuclei should show prolonged latencies in AD but not in MD. In 55 AD patients, 57 MD patients and two age-matched control groups evoked potentials were recorded upon stimulation of the auricular branch of the vagus nerve. In the AD, not in the MD group, latencies were significantly longer as compared to controls. Thus, the method of VSEP could contribute to the important differential diagnosis of AD and MD in elderly patients.


Frontiers in Human Neuroscience | 2017

Reduced activity in the right inferior frontal gyrus in Elderly APOE-E4 carriers during a verbal fluency task

Andrea Katzorke; Julia Zeller; Laura D. Müller; Martin Lauer; Thomas Polak; Andreas Reif; Jürgen Deckert; Martin J. Herrmann

Apolipoprotein-E4 (APOE-E4) is a major genetic risk factor for developing Alzheimer’s disease (AD). The verbal fluency task (VFT), especially the subtask category fluency, has shown to provide a good discrimination between cognitively normal controls and subjects with AD. Interestingly, APOE-E4 seems to have no effect on the behavioral performance during a VFT in healthy elderly. Thus, the purpose of the present study was to reveal possible compensation mechanisms by investigating the effect of APOE-E4 on the hemodynamic response in non-demented elderly during a VFT by using functional near-infrared spectroscopy (fNIRS). We compared performance and hemodynamic response of high risk APOE-E4/E4, -E3/E4 carriers with neutral APOE-E3/E3 non-demented subjects (N = 288; 70–77 years). No difference in performance was found. APOE-E4/E4, -E3/E4 carriers had a decreased hemodynamic response in the right inferior frontal junction (IFJ) with a corresponding higher response in the left middle frontal gyrus (MFG) during category fluency. Performance was correlated with the hemodynamic response in the MFG. We assume a compensation of decreased IFJ brain activation by utilizing the MFG during category fluency and thus resulting in no behavioral differences between APOE-groups during the performance of a VFT.


Psychiatry Research-neuroimaging | 2018

Decreased hemodynamic response in inferior frontotemporal regions in elderly with mild cognitive impairment

Andrea Katzorke; Julia Zeller; Laura D. Müller; Martin Lauer; Thomas Polak; Jürgen Deckert; Martin J. Herrmann

The verbal fluency task (VFT) is a well-established cognitive marker for mild cognitive impairment (MCI) in the prodromal stage of Alzheimer´s dementia (AD). The behavioral VFT performance of patients allows the prediction of dementia two years later. But effective compensatory mechanism might cover or reduce the predictive value of the VFT. Therefore the aim of this study is to measure the hemodynamic response during VFT in patients with mild cognitive impairment (MCI) to establish the hemodynamic response during the VFT as a screening instrument for the prediction of dementia. One method which allows measuring the hemodynamic response during speech production without severe problems with moving artifacts like in functional magnetic resonance imaging (fMRI) is the functional near-infrared spectroscopy (fNIRS). It is optimal as a screening instrument, as it is easy to apply and without any contraindications. In this study we assessed the hemodynamic response in prefrontal and temporal regions in patients with MCI as well as matched healthy controls with fNIRS. We found a decreased hemodynamic response in the inferior frontotemporal cortex for the MCI group. Our results indicate that a frontotemporal decreased hemodynamic response could serve as a diagnostic biomarker for dementia.


Alzheimers & Dementia | 2011

Near-infrared spectroscopy: a reliable tool to assess cortical changes in Alzheimer's disease and their progression over time

Julia Zeller; Thomas Polak; Andreas J. Fallgatter

the VFT subjects displayed a typical activation pattern in the DLPFC with a distinct increase in O2Hb. Subjects’ lateralisation did not correlate with age. The amount of lateralisation during the letter version could account for a significant amount of the changes in MMST (16%) and DemTect (9%) after one year. Subjects displaying less distinct or no lateralisation showed a decrease in neuropsychological performance whereas subjects with a clearly lateralized activation did not change in MMSTor DemTect. Conclusions: fNIRS seems to be a suitable tool for the study of long term changes in elderly subjects when assessing brain activation and cognitive decline. As alternations in oxygenation probably occur even before atrophy in affected brain regions, fNIRS could add to the development of methods for the early detection of mild cognitive impairment or Alzheimer’s disease.


Journal of Neural Transmission | 2017

Near-infrared spectroscopy (NIRS) and vagus somatosensory evoked potentials (VSEP) in the early diagnosis of Alzheimer's disease: rationale, design, methods, and first baseline data of the Vogel study.

Thomas Polak; Martin J. Herrmann; Laura D. Müller; Julia Zeller; Andrea Katzorke; Matthias Fischer; Fabian Spielmann; Erik Weinmann; Leif Hommers; Martin Lauer; Andreas J. Fallgatter; Jürgen Deckert


Brain Imaging and Behavior | 2018

Reduced spontaneous low frequency oscillations as measured with functional near-infrared spectroscopy in mild cognitive impairment

Julia Zeller; Andrea Katzorke; Laura D. Müller; Judith Breunig; Florian B. Haeussinger; Jürgen Deckert; Bodo Warrings; Martin Lauer; Thomas Polak; Martin J. Herrmann


European Journal of Pain Supplements | 2011

S234 BILATERAL CORTICAL ACTIVATION IN FIBROMYALGIA PATIENTS AFTER UNILATERAL PAINFUL STIMULATION MEASURED WITH NEAR-INFRARED SPECTROSCOPY

Nurcan Üçeyler; S. Kewenig; Julia Zeller; Andreas J. Fallgatter; Claudia Sommer

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Thomas Polak

University of Würzburg

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Martin Lauer

University of Würzburg

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