Gergely Orsi

Gergely Orsi

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 May 2017 in Scientific Reports
Verified
Journal Article
Open access
PDF file
GPGabor Perlaki
Gabor Perlaki
RHReka Horvath
Reka Horvath
SNSzilvia Anett Nagy
Szilvia Anett Nagy
PBPeter Bogner
Peter Bogner
TDTamas Doczi
Tamas Doczi
GOGergely Orsi
Gergely Orsi
Although several methods have been developed to automatically delineate subcortical gray matter structures from MR images, the accuracy of these algorithms has not been comprehensively examined. Most of earlier studies focused primarily on the hippocampus. Here, we assessed the accuracy of two widely used non-commercial programs (FSL-FIRST and Freesurfer) for segmenting the caudate and putamen. T1-weighted 1 mm3 isotropic resolution MR images were acquired for thirty healthy subjects (15 females). Caudate nucleus and putamen were segmented manually by two independent observers and automatically by FIRST and Freesurfer (v4.5 and v5.3). Utilizing manual labels as reference standard the following measures were studied: Dice coefficient (D), percentage volume difference (PVD), absolute volume difference as well as intraclass correlation coefficient (ICC) for consistency and absolute agreement. For putamen segmentation, FIRST achieved higher D, lower PVD and higher ICC for absolute agreement with manual tracing than either version of Freesurfer. Freesurfer overestimated the putamen, while FIRST was not statistically different from manual tracing. The ICC for consistency with manual tracing was similar between the two methods. For caudate segmentation, FIRST and Freesurfer performed more similarly. In conclusion, Freesurfer and FIRST are not equivalent when comparing to manual tracing. FIRST was superior for putaminal segmentation.

18 October 2018 in PLOS ONE
Verified
Journal Article
Open access
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GPGabor Perlaki
Gabor Perlaki
DMDenes Molnar
Denes Molnar
PSPaul A. M. Smeets
Paul A. M. Smeets
WAWolfgang Ahrens
Wolfgang Ahrens
MWMaike Wolters
Maike Wolters
OCon behalf of the I.Family Consortium
on behalf of the I.Family Consortium
Neuroimaging data suggest that pediatric overweight and obesity are associated with morphological alterations in gray matter (GM) brain structures, but previous studies using mainly voxel-based morphometry (VBM) showed inconsistent results. Here, we aimed to examine the relationship between youth obesity and the volume of predefined reward system structures using magnetic resonance (MR) volumetry. We also aimed to complement volumetry with VBM-style analysis. Fifty-one Caucasian young subjects (32 females; mean age: 13.8±1.9, range: 10.2–16.5 years) were included. Subjects were selected from a subsample of the I.Family study examined in the Hungarian center. A T1-weighted 1 mm3 isotropic resolution image was acquired. Age- and sex-standardized body mass index (zBMI) was assessed at the day of MRI and ~1.89 years (mean±SD: 689±188 days) before the examination. Obesity related GM alterations were investigated using MR volumetry in five predefined brain structures presumed to play crucial roles in body weight regulation (hippocampus, amygdala, accumbens, caudate, putamen), as well as whole-brain and regional VBM. The volumes of accumbens and amygdala showed significant positive correlations with zBMI, while their GM densities were inversely related to zBMI. Voxel-based GM mass also showed significant negative correlation with zBMI when investigated in the predefined amygdala region, but this relationship was mediated by GM density. Overweight/obesity related morphometric brain differences already seem to be present in children/adolescents. Our work highlights the disparity between volume and VBM-derived measures and that GM mass (combination of volume and density) is not informative in the context of obesity related volumetric changes. To better characterize the association between childhood obesity and GM morphometry, a combination of volumetric segmentation and VBM methods, as well as future longitudinal studies are necessary. Our results suggest that childhood obesity is associated with enlarged structural volumes, but decreased GM density in the reward system.

5 December 2023 in Brain Imaging and Behavior
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Journal Article
Open access
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EÁEszter Áfra
Eszter Áfra
Jozsef JANSZKYJozsef JANSZKY
Jozsef JANSZKY
GPGábor Perlaki
Gábor Perlaki
GOGergely Orsi
Gergely Orsi
SNSzilvia Anett Nagy
Szilvia Anett Nagy
GDGergely Darnai
Gergely Darnai
Nowadays, the limitless availability to the World Wide Web can lead to general Internet misuse and dependence. Currently, smartphone and social media use belong to the most prevalent Internet-related behavioral addiction forms. However, the neurobiological background of these Internet-related behavioral addictions is not sufficiently explored. In this study, these addiction forms were assessed with self-reported questionnaires. Resting-state functional magnetic resonance imaging was acquired for all participants (n = 59, 29 males) to examine functional brain networks. The resting-state networks that were discovered using independent component analysis were analyzed to estimate within network differences. Significant negative associations with social media addiction and smartphone addiction were found in the language network, the lateral visual networks, the auditory network, the sensorimotor network, the executive network and the frontoparietal network. These results suggest that problematic smartphone and social media use are associated with sensory processing and higher cognitive functioning.

1 October 2014 in Experimental Gerontology
Verified
Journal Article
Closed access
MVMárk Váczi
Márk Váczi
SNSzilvia Anett Nagy
Szilvia Anett Nagy
TKTamás Kőszegi
Tamás Kőszegi
Mira AmbrusMira Ambrus
Mira Ambrus
PBPéter Bogner
Péter Bogner
Tibor HortobagyiTibor Hortobagyi
Tibor Hortobagyi

1 February 2015 in Journal of the Neurological Sciences
Verified
Journal Article
Closed access
GPGabor Perlaki
Gabor Perlaki
GOGergely Orsi
Gergely Orsi
ASAttila Schwarcz
Attila Schwarcz
PBPeter Bodi
Peter Bodi
EPEniko Plozer
Eniko Plozer
JJJozsef Janszky
Jozsef Janszky

26 May 2017 in Multiple Sclerosis Journal
Verified
Journal Article
Closed access
MPMiklós Palotai
Miklós Palotai
AMAndrea Mike
Andrea Mike
MCMichele Cavallari
Michele Cavallari
ESErzsebet Strammer
Erzsebet Strammer
GOGergely Orsi
Gergely Orsi
CGCharles Rg Guttmann
Charles Rg Guttmann
Background: Reports on the relationships between white matter lesion load (WMLL) and fatigue and anxiety in multiple sclerosis (MS) are inconsistent. Objective: To investigate the association of total and tract-specific WMLL with fatigue and anxiety. Methods: Total and regional T2 WMLL was assessed for 19 tracts in 48 MS patients (30 females). ICBM-DTI-81 Atlas-based parcellation was combined with WMLL segmentation of T2-weighted magnetic resonance imaging (MRI). Fatigue, anxiety, and depression were assessed using Fatigue Impact Scale, State Trait Anxiety Inventory, and Beck Depression Inventory, respectively. Results: Fatigue, anxiety, and depression showed significant inter-correlation. We found no association between fatigue and total or regional WMLLs, whereas anxiety was associated with total and regional WMLLs in nine tracts. After adjusting for total WMLL, age, and depression, only the column and body of the fornix (CBF) remained significantly associated with anxiety. Post hoc analyses showed no CBF lesions on T1-weighted MRI and suggested, but could not confirm, that the septum pellucidum might play a role in the pathogenesis of anxiety. Conclusion: Our results suggest that anxiety in MS patients may have a neuropathological substrate in the septo-fornical area, which requires further validation using larger sample size and ultra-high-field MRI in targeted prospective studies.