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53. Substantial and reversible brain gray matter reduction but no acute brain lesions in ultramarathon runners: experience from the TransEurope-FootRace Project

Author

Freund Wolfgang, Faust Sonja, Birklein Frank, Gaser Christian, Wunderlich Arthur P, Müller Marguerite, Billich Christian, Juchems Markus S, Schmitz Bernd L, Grön Georg, and Schütz Uwe H

Subjects
body weight, brain volume, catabolism, DWI, lesion, MRI, ultramarathon, Medicine
Abstract

Abstract Background During the extremely challenging 4,487 km ultramarathon TransEurope-FootRace 2009, runners showed considerable reduction of body weight. The effects of this endurance run on brain volume changes but also possible formation of brain edema or new lesions were explored by repeated magnetic resonance imaging (MRI) studies. Methods A total of 15 runners signed an informed consent to participate in this study of planned brain scans before, twice during, and about 8 months after the race. Because of dropouts, global gray matter volume analysis could only be performed in ten runners covering three timepoints, and in seven runners who also had a follow-up scan. Scanning was performed on three identical 1.5 T Siemens MAGNETOM Avanto scanners, two of them located at our university. The third MRI scanner with identical sequence parameters was a mobile MRI unit escorting the runners. Volumetric 3D datasets were acquired using a magnetization prepared rapid acquisition gradient echo (MPRAGE) sequence. Additionally, diffusion-weighted (DWI) and fluid attenuated inversion recovery (FLAIR) imaging was performed. Results Average global gray matter volume as well as body weight significantly decreased by 6% during the race. After 8 months, gray matter volume returned to baseline as well as body weight. No new brain lesions were detected by DWI or FLAIR imaging. Conclusions Physiological brain volume reduction during aging is less than 0.2% per year. Therefore a volume reduction of about 6% during the 2 months of extreme running appears to be substantial. The reconstitution in global volume measures after 8 months shows the process to be reversible. As possible mechanisms we discuss loss of protein, hypercortisolism and hyponatremia to account for both substantiality and reversibility of gray matter volume reductions. Reversible brain volume reduction during an ultramarathon suggests that extreme running might serve as a model to investigate possible mechanisms of transient brain volume changes. However, despite massive metabolic load, we found no new lesions in trained athletes participating in a multistage ultramarathon. See related commentary http://www.biomedcentral.com/1741-7015/10/171

Published
2012
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54. Somatosensory stimulus intensity encoding in borderline personality disorder

Author

Malejko, Kathrin, Neff, Dominik, Brown, Rebecca Corinna, Plener, Paul L., Bonenberger, Martina, Abler, Birgit, Grön, Georg, and Graf, Heiko

Subjects
Magnetic resonance imaging, ddc:150, stimulus processing, Borderline personality disorder, Funktionelle Kernspintomografie, borderline, fMRI, pain, Borderline-Persönlichkeitsstörung, parametric
Published
2018

57. From uncertainty to reward: BOLD characteristics differentiate signaling pathways

Author

Grön Georg, Herrnberger Bärbel, Abler Birgit, and Spitzer Manfred

Subjects
Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571, Neurophysiology and neuropsychology, QP351-495
Abstract

Abstract Background Reward value and uncertainty are represented by dopamine neurons in monkeys by distinct phasic and tonic firing rates. Knowledge about the underlying differential dopaminergic pathways is crucial for a better understanding of dopamine-related processes. Using functional magnetic resonance blood-oxygen level dependent (BOLD) imaging we analyzed brain activation in 15 healthy, male subjects performing a gambling task, upon expectation of potential monetary rewards at different reward values and levels of uncertainty. Results Consistent with previous studies, ventral striatal activation was related to both reward magnitudes and values. Activation in medial and lateral orbitofrontal brain areas was best predicted by reward uncertainty. Moreover, late BOLD responses relative to trial onset were due to expectation of different reward values and likely to represent phasic dopaminergic signaling. Early BOLD responses were due to different levels of reward uncertainty and likely to represent tonic dopaminergic signals. Conclusions We conclude that differential dopaminergic signaling as revealed in animal studies is not only represented locally by involvement of distinct brain regions but also by distinct BOLD signal characteristics.

Published
2009
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59. Differential neural processing of social exclusion and inclusion in adolescents with non-suicidal self-injury and young adults with borderline personality disorder

Author

Brown, Rebecca Corinna, Plener, Paul L., Grön, Georg, Neff, Dominik, Bonenberger, Martina Alexandra, and Abler, Birgit

Subjects
non-suicidal self-injury, Magnetic resonance imaging, ddc:150, Borderline personality disorder, Selbstbeschädigung, fMRI, self-injury, social situations, Borderline-Persönlichkeitsstörung, ddc:610, Self-injurious behavior
Published
2017

63. A Neural Mechanism of Strategic Social Choice under Sanction-Induced Norm Compliance1,2,3

Author

Makwana, Aidan, Grön, Georg, Fehr, Ernst, and Hare, Todd A.

Subjects
Cognition and Behavior, norm compliance, fMRI, functional connectivity, decision-making, New Research, strategy
Abstract

In recent years, much has been learned about the representation of subjective value in simple, nonstrategic choices. However, a large fraction of our daily decisions are embedded in social interactions in which value guided decisions require balancing benefits for self against consequences imposed by others in response to our choices. Yet, despite their ubiquity, much less is known about how value computation takes place in strategic social contexts that include the possibility of retribution for norm violations. Here, we used functional magnetic resonance imaging (fMRI) to show that when human subjects face such a context connectivity increases between the temporoparietal junction (TPJ), implicated in the representation of other peoples’ thoughts and intentions, and regions of ventromedial prefrontal cortex (vmPFC) that are associated with value computation. In contrast, we find no increase in connectivity between these regions in social nonstrategic cases where decision-makers are immune from retributive monetary punishments from a human partner. Moreover, there was also no increase in TPJ-vmPFC connectivity when the potential punishment was performed by a computer programmed to punish fairness norm violations in the same manner as a human would. Thus, TPJ-vmPFC connectivity is not simply a function of the social or norm enforcing nature of the decision, but rather occurs specifically in situations where subjects make decisions in a social context and strategically consider putative consequences imposed by others.

Published
2015

67. Responsivität des zerebralen Belohnungssystems bei jugendlichen und erwachsenen Patientinnen mit Anorexia nervosa

Author

Fladung, Anne-Katharina, Bauer, Kathrin, Schöll, Friederike, Schulze, Ulrike, Uttner, Ingo, Lulé, Dorothée, Von Wietersheim, Jörn, and Grön, Georg

Subjects
ddc: 610, 610 Medical sciences, Medicine
Abstract

Hintergrund: Tierstudien zeigen, dass eine Kombination aus Diät und freiwilliger physischer Aktivität zu einem Gewichtsverlust bis hin zum Tod führen kann. In diesem Zusammenhang wird vermutet, dass Prozesse im mesolimbischen, dopaminergen Belohnungssystem des Gehirns das Hungern positiv[for full text, please go to the a.m. URL], 3. Wissenschaftlicher Kongress der Deutschen Gesellschaft für Essstörungen

Published
2012

73. Monocular visual activation patterns in albinism as revealed by functional magnetic resonance imaging

Author

Schmitz, Bernd, Käsmann‐Kellner, Barbara, Schäfer, Torsten, Krick, Christoph M., Grön, Georg, Backens, Martin, and Reith, Wolfgang

Subjects
Adult, Male, Brain Mapping, genetic structures, Albinism, Ocular, Magnetic Resonance Imaging, eye diseases, Functional Laterality, Vision, Monocular, Optic Chiasm, Humans, Female, Research Articles, Photic Stimulation, Visual Cortex
Abstract

Human albinism is characterized by a disturbance of the chiasmatic projection system leading to predominant representation of just one eye in the contralateral hemisphere. Patients show congenital nystagmus without perceiving oscillopsia. The purpose of the present study was to demonstrate the consequences of atypical chiasmatic crossing with monocular visual stimulation using functional magnetic resonance imaging (fMRI). Sixteen patients with albinism and fifteen normally pigmented controls were stimulated with a monocular visual activation paradigm using flickering checkerboards. In patients, we observed contralaterally dominated activation of visual cortices correlating to clinical albinism parameters. This confirms albinism as a continuous range of hypopigmentation disorders. Additionally, albinos showed activation of the superior colliculus and of visual motion areas although the stimulus was stationary. Activation of visual motion areas is due probably to congenital nystagmus without a conscious correlate like oscillopsia. Hum. Brain Mapping 23:40–52, 2004. © 2004 Wiley‐Liss, Inc.

Published
2004

77. Mental Arithmetic Tasks

Author

Ulrich, Martin, primary, Keller, Johannes, additional, Hoenig, Klaus, additional, Waller, Christiane, additional, and Grön, Georg, additional

Published
2014
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78. Impact of the control for corrupted diffusion tensor imaging data in comparisons at the group level: an application in Huntington disease

Author

Müller, Hans-Peter, primary, Kassubek, Jan, additional, Grön, Georg, additional, Sprengelmeyer, Reiner, additional, Ludolph, Albert C, additional, Klöppel, Stefan, additional, Hobbs, Nicola Z, additional, Roos, Raymund AC, additional, Duerr, Alexandra, additional, Tabrizi, Sarah J, additional, Orth, Michael, additional, Süssmuth, Sigurd D, additional, and Landwehrmeyer, G, additional

Published
2014
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82. Evaluating multicenter DTI data in Huntington's disease on site specific effects: An ex post facto approach

Author

Müller, Hans-Peter, primary, Grön, Georg, additional, Sprengelmeyer, Reiner, additional, Kassubek, Jan, additional, Ludolph, Albert C., additional, Hobbs, Nicola, additional, Cole, James, additional, Roos, Raymund A.C., additional, Duerr, Alexandra, additional, Tabrizi, Sarah J., additional, Landwehrmeyer, G. Bernhard, additional, and Süssmuth, Sigurd D., additional

Published
2013
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83. Neural signatures of experimentally induced flow experiences identified in a typical fMRI block design with BOLD imaging.

Author

Ulrich, Martin, Keller, Johannes, and Grön, Georg

Subjects
FUNCTIONAL magnetic resonance imaging, MOOD (Psychology), AMYGDALOID body, HEALTH, HEALTH behavior, BOREDOM
Abstract

Previously, experimentally induced flow experiences have been demonstrated with perfusion imaging during activation blocks of 3min length to accommodate with the putatively slowly evolving "mood" characteristics of flow. Here, we used functional magnetic resonance imaging (fMRI) in a sample of 23 healthy,male participants to investigate flow in the context of a typical fMRI block design with block lengths as short as 30 s. To induce flow, demands of arithmetic tasks were automatically and continuously adjusted to the individual skill level. Compared against conditions of boredom and overload, experience of flow was evident fromindividuals' reported subjective experiences and changes in electrodermal activity. Neural activation was relatively increased during flow, particularly in the anterior insula, inferior frontal gyri, basal ganglia andmidbrain. Relative activation decreases during flow were observed inmedial prefrontal and posterior cingulate cortex, and in themedial temporal lobe including the amygdala. Present findings suggest that even in the context of comparably short activation blocks flow can be reliably experienced and is associated with changes in neural activation of brain regions previously described. Possiblemechanisms of interacting brain regions are outlined, awaiting further investigation which should now be possible given the greater temporal resolution compared with previous perfusion imaging. [ABSTRACT FROM AUTHOR]

Published
2016
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