@article{KatzorkeZellerMuelleretal.2017, author = {Katzorke, Andrea and Zeller, Julia B. M. and M{\"u}ller, Laura D. and Lauer, Martin and Polak, Thomas and Reif, Andreas and Deckert, J{\"u}rgen and Herrmann, Martin J.}, title = {Reduced activity in the right inferior frontal gyrus in elderly APOE-E4 carriers during a verbal fluency task}, series = {Frontiers in Human Neuroscience}, volume = {11}, journal = {Frontiers in Human Neuroscience}, doi = {10.3389/fnhum.2017.00046}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171892}, year = {2017}, abstract = {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.}, language = {en} } @article{VernerHerrmannTrocheetal.2013, author = {Verner, Martin and Herrmann, Martin J. and Troche, Stefan J. and Roebers, Claudia M. and Rammsayer, Thomas H.}, title = {Cortical oxygen consumption in mental arithmetic as a function of task difficulty: a near-infrared spectroscopy approach}, series = {Frontiers in Human Neuroscience}, volume = {7}, journal = {Frontiers in Human Neuroscience}, number = {217}, issn = {1662-5161}, doi = {10.3389/fnhum.2013.00217}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122449}, year = {2013}, abstract = {The present study investigated changes in cortical oxygenation during mental arithmetic using near-infrared spectroscopy (NIRS). Twenty-nine male volunteers were examined using a 52-channel continuous wave system for analyzing activity in prefrontal areas. With the help of a probabilistic mapping method, three regions of interest (ROIs) on each hemisphere were defined: The inferior frontal gyri (IFG), the middle frontal gyri (MFG), and the superior frontal gyri (SFG). Oxygenation as an indicator of functional brain activation was compared over the three ROI and two levels of arithmetic task difficulty (simple and complex additions). In contrast to most previous studies using fMRI or NIRS, in the present study arithmetic tasks were presented verbally in analogue to many daily life situations. With respect to task difficulty, more complex addition tasks led to higher oxygenation in all defined ROI except in the left IFG compared to simple addition tasks. When compared to the channel positions covering different gyri of the temporal lobe, the observed sensitivity to task complexity was found to be restricted to the specified ROIs. As to the comparison of ROIs, the highest oxygenation was found in the IFG, while MFG and SFG showed significantly less activation compared to IFG. The present cognitive-neuroscience approach demonstrated that NIRS is a suitable and highly feasible research tool for investigating and quantifying neural effects of increasing arithmetic task difficulty.}, language = {en} } @article{UeceylerKewenigKittelSchneideretal.2015, author = {{\"U}{\c{c}}eyler, Nurcan and Kewenig, Susanne and Kittel-Schneider, Sarah and Fallgatter, Andreas J. and Sommer, Claudia}, title = {Increased cortical activation upon painful stimulation in fibromyalgia syndrome}, series = {BMC Neurology}, volume = {15}, journal = {BMC Neurology}, number = {210}, doi = {10.1186/s12883-015-0472-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125230}, year = {2015}, abstract = {Background Fibromyalgia 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). Methods Two 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). Results FMS 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). Conclusion Our data give further evidence for altered central nervous processing in patients with FMS and the distinction between FMS and MD.}, language = {en} } @article{KopfDreslerReichertsetal.2013, author = {Kopf, Juliane and Dresler, Thomas and Reicherts, Philipp and Herrmann, Martin J. and Reif, Andreas}, title = {The Effect of Emotional Content on Brain Activation and the Late Positive Potential in a Word n-back Task}, series = {PLoS ONE}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0075598}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96687}, year = {2013}, abstract = {Introduction There is mounting evidence for the influence of emotional content on working memory performance. This is particularly important in light of the emotion processing that needs to take place when emotional content interferes with executive functions. In this study, we used emotional words of different valence but with similar arousal levels in an n-back task. Methods We examined the effects on activation in the prefrontal cortex by means of functional near-infrared spectroscopy (fNIRS) and on the late positive potential (LPP). FNIRS and LPP data were examined in 30 healthy subjects. Results Behavioral results show an influence of valence on the error rate depending on the difficulty of the task: more errors were made when the valence was negative and the task difficult. Brain activation was dependent both on the difficulty of the task and on the valence: negative valence of a word diminished the increase in activation, whereas positive valence did not influence the increase in activation, while difficulty levels increased. The LPP also differentiated between the different valences, and in addition was influenced by the task difficulty, the more difficult the task, the less differentiation could be observed. Conclusions Summarized, this study shows the influence of valence on a verbal working memory task. When a word contained a negative valence, the emotional content seemed to take precedence in contrast to words containing a positive valence. Working memory and emotion processing sites seemed to overlap and compete for resources even when words are carriers of the emotional content.}, language = {en} }