Analysis of the Brain-activation Areas During the Visual Stimulations of 2D and 3D Imagery using Functional Magnetic Resonance Imaging

Yeong-Cheol Heo,Hae-Kag Lee,Jae-Hwan Cho 한국자기학회 2017 Journal of Magnetics Vol.22 No.4

The aim of this study is an functional magnetic resonance imaging (fMRI) investigation of the activity of the Brodmann brain areas during the viewing of 2D and 3D images. By using the 3.0 Tesla MRI system, an 8-channel SENSE Head Coil, and the ESys fMRI system in 5 adult males, 3D T1-weighted images were obtained from anatomic images. A gradient-EPI sequence was used for the acquisition of the brain functional images. The monitor was installed so that the images could be seen through a mirror located in the coil. The 3D appearance of the triangular, cubic, and hexagonal shapes were visually stimulated by the 2D and 3D images, and a pair of red–blue cardboard glasses was worn during the viewing of the 3D images. The display object is composed of 4 stimulus projections every 60 s and 4 resting periods of 20 s every 20 s. The acquired data were analyzed using the SPM-8 program. For the 2D imagery, the activation area of the brain is larger than that of the 3D imagery (p < .05). In the visual-cortex activation area, the number of clusters is larger for the 3D imagery (p < .05). It is expected that the basic data of this study will be used to analyze the effects of 3D-image contents on the areas of the human brain.

Improved Diagnostic Accuracy of Alzheimer's Disease by Combining Regional Cortical Thickness and Default Mode Network Functional Connectivity: Validated in the Alzheimer's Disease Neuroimaging Initiative Set

Park, Ji Eun,Park, Bumwoo,Kim, Sang Joon,Kim, Ho Sung,Choi, Choong Gon,Jung, Seung Chai,Oh, Joo Young,Lee, Jae-Hong,Roh, Jee Hoon,Shim, Woo Hyun The Korean Society of Radiology 2017 KOREAN JOURNAL OF RADIOLOGY Vol.18 No.6

<P><B>Objective</B></P><P>To identify potential imaging biomarkers of Alzheimer's disease by combining brain cortical thickness (CThk) and functional connectivity and to validate this model's diagnostic accuracy in a validation set.</P><P><B>Materials and Methods</B></P><P>Data from 98 subjects was retrospectively reviewed, including a study set (n = 63) and a validation set from the Alzheimer's Disease Neuroimaging Initiative (n = 35). From each subject, data for CThk and functional connectivity of the default mode network was extracted from structural T1-weighted and resting-state functional magnetic resonance imaging. Cortical regions with significant differences between patients and healthy controls in the correlation of CThk and functional connectivity were identified in the study set. The diagnostic accuracy of functional connectivity measures combined with CThk in the identified regions was evaluated against that in the medial temporal lobes using the validation set and application of a support vector machine.</P><P><B>Results</B></P><P>Group-wise differences in the correlation of CThk and default mode network functional connectivity were identified in the superior temporal (<I>p</I> < 0.001) and supramarginal gyrus (<I>p</I> = 0.007) of the left cerebral hemisphere. Default mode network functional connectivity combined with the CThk of those two regions were more accurate than that combined with the CThk of both medial temporal lobes (91.7% vs. 75%).</P><P><B>Conclusion</B></P><P>Combining functional information with CThk of the superior temporal and supramarginal gyri in the left cerebral hemisphere improves diagnostic accuracy, making it a potential imaging biomarker for Alzheimer's disease.</P>

Improved Diagnostic Accuracy of Alzheimer’s Disease by Combining Regional Cortical Thickness and Default Mode Network Functional Connectivity: Validated in the Alzheimer’s Disease Neuroimaging Initiative Set

박지은,박범우,김상준,김호성,최충곤,정승채,오주영,이재홍,노지훈,심우현,Alzheimer’s Disease Neuroimaging Initiative (ADNI) 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.6

Objective: To identify potential imaging biomarkers of Alzheimer’s disease by combining brain cortical thickness (CThk) and functional connectivity and to validate this model’s diagnostic accuracy in a validation set. Materials and Methods: Data from 98 subjects was retrospectively reviewed, including a study set (n = 63) and a validation set from the Alzheimer’s Disease Neuroimaging Initiative (n = 35). From each subject, data for CThk and functional connectivity of the default mode network was extracted from structural T1-weighted and resting-state functional magnetic resonance imaging. Cortical regions with significant differences between patients and healthy controls in the correlation of CThk and functional connectivity were identified in the study set. The diagnostic accuracy of functional connectivity measures combined with CThk in the identified regions was evaluated against that in the medial temporal lobes using the validation set and application of a support vector machine. Results: Group-wise differences in the correlation of CThk and default mode network functional connectivity were identified in the superior temporal (p < 0.001) and supramarginal gyrus (p = 0.007) of the left cerebral hemisphere. Default mode network functional connectivity combined with the CThk of those two regions were more accurate than that combined with the CThk of both medial temporal lobes (91.7% vs. 75%). Conclusion: Combining functional information with CThk of the superior temporal and supramarginal gyri in the left cerebral hemisphere improves diagnostic accuracy, making it a potential imaging biomarker for Alzheimer’s disease.

Inter-vender and test-retest reliabilities of resting-state functional magnetic resonance imaging: Implications for multi-center imaging studies

An, Hyeong Su,Moon, Won-Jin,Ryu, Jae-Kyun,Park, Ju Yeon,Yun, Won Sung,Choi, Jin Woo,Jahng, Geon-Ho,Park, Jang-Yeon Elsevier 2017 Magnetic resonance imaging Vol.44 No.-

<P><B>Abstract</B></P> <P>This prospective multi-center study aimed to evaluate the inter-vendor and test-retest reliabilities of resting-state functional magnetic resonance imaging (RS-fMRI) by assessing the temporal signal-to-noise ratio (tSNR) and functional connectivity. Study included 10 healthy subjects and each subject was scanned using three 3T MR scanners (GE Signa HDxt, Siemens Skyra, and Philips Achieva) in two sessions. The tSNR was calculated from the time course data. Inter-vendor and test-retest reliabilities were assessed with intra-class correlation coefficients (ICCs) derived from variant component analysis. Independent component analysis was performed to identify the connectivity of the default-mode network (DMN). In result, the tSNR for the DMN was not significantly different among the GE, Philips, and Siemens scanners (<I>P</I> =0.638). In terms of vendor differences, the inter-vendor reliability was good (ICC=0.774). Regarding the test-retest reliability, the GE scanner showed excellent correlation (ICC=0.961), while the Philips (ICC=0.671) and Siemens (ICC=0.726) scanners showed relatively good correlation. The DMN pattern of the subjects between the two sessions for each scanner and between three scanners showed the identical patterns of functional connectivity. The inter-vendor and test-retest reliabilities of RS-fMRI using different 3T MR scanners are good. Thus, we suggest that RS-fMRI could be used in multicenter imaging studies as a reliable imaging marker.</P>

문제적 과잉 성 행동자의 휴지기 상태 시 집행 통제 회로의 기능적 연결성 변화

석지우 한국감성과학회 2019 감성과학 Vol.22 No.1

Individuals with Problematic hypersexual behavior (PHB) has shown the in the inability to control sexual impulses and arousal. The previous studies identified these characteristics are related to the structural and functional changes of the brain region responsible for inhibitory functions. However, very little research has been done on functional connectivities among the brain areas during the resting state in Individuals with Problematic hypersexual behavior. Therefore, the purpose of this study is to identify the deficit of the functional connectivity in the executive control network during resting state using functional magnetic resonance imaging devices among Individuals with Problematic hypersexual behavior. For this study, magnetic resonance imaging data were obtained for 16 individuals with PHB and 19 normal controls with similar demographic characteristics. The areas related to the executive control network (LECN, RECN) were selected as the region of interest, and the correlation coefficient with time series signals between these areas was measured to identify the functional connectivity, and between groups analysis was used. The results showed a significant difference in the functional connectivity strength of executive control network between two groups. In other words, there are the decreased functional connectivities between superior/middle frontal gyrus and caudate, and between superior/middle frontal gyrus and superior parietal gyrus/angular gyrus in the individuals with PHB. In addition, these functional connectivities were related to the severity of hypersexual behavior. The results of this study suggest that the inability to control sexual impulses and arousal in individuals with PHB might be related to the reduced functional connectivity of executive control circuits. 문제적 과잉 성 행동은 성 충동과 각성을 통제하지 못하는 것과 관련이 있으며, 억제 기능을 담당하는 뇌 영역의 구조적, 기능적 변화와 관련이 있음이 밝혀졌다. 그러나 아직까지 문제적 과잉 성 행동의 휴지기 상태 시 뇌의 기능적 연결성에 관한 연구는 거의 없다. 따라서 본 연구에서는 자기공명영상장치를 사용하여 휴지기 상태 시 문제적 과잉 성 행동자의 집행 통제 회로(RECN, LECN)의 기능적 연결성의 결함을 규명하고자 하였다. 이를 위해 17명의 문제적 과잉 성 행동자와 인구통계학적 특성이 유사한 20명의 정상대조군을 대상으로 휴지기 상태 시 자기공명영상데이터가 획득하였다. 실행기능 제어 회로(LECN, RECN)와 관련된 영역을 관심 뇌 영역으로 선정하였으며, 이들 영역간 시계열 신호와의 상관계수를 기능 연결성 정도로 가정하고 집단 간 비교 검증을 하였다. 그 결과, 정상대조군과 문제적 과잉 성행동군의 집행 통제회로의 기능적 연결 강도에 유의한 차이가 나타났다. 즉, 정상대조군에 비해 문제적 과잉 성행동군은 상/중전두회와 미상핵, 상/중전두회와 두정회의 기능적 연결성이 저하된 것으로 나타났다. 또한, 이 영역간 기능적 연결강도는 과잉 성 행동 지수와 부적상관이 있는 것으로 나타났다. 본 연구 결과는 문제적 과잉 성행동자들이 성 충동과 각성을 제어하지 못하는 것이 집행 통제회로의 기능적 연결성 저하와 관련이 있음을 시사한다.

Differences in Functional Connectivity of the Insula Between Brain Wave Vibration in Meditators and Non-meditators

Jang, Joon Hwan,Kim, Jae-Hun,Yun, Je-Yeon,Choi, Soo-Hee,An, Seung Chan,Kang, Do-Hyung Springer US 2018 Mindfulness Vol.9 No.6

<P>The majority of meditation involves focusing attention on internal events or sensations and becoming aware of emotions. The insula cortex, through a functional connection with the prefrontal cortex and other brain regions, plays a key role in integrating external sensory information with internal bodily state signals and emotional awareness. The purpose of this exploratory study was to examine the resting-state functional connectivity of the insula with other brain regions in meditation practitioners and control subjects. Thirty-five Brain Wave Vibration meditation practitioners and 33 controls without meditation experience were included in this study. All subjects underwent 4.68-min resting-state functional scanning runs using magnetic resonance imaging. The anterior and posterior insulae were chosen as seed regions for the functional connectivity map. Meditation practitioners showed significantly greater insula-related functional connectivity in the thalamus, caudate, middle frontal gyrus, and superior temporal gyrus than did controls. Control subjects demonstrated greater functional connectivity with the posterior insula in the parahippocampal gyrus. Our findings suggest that the practice of Brain Wave Vibration meditation may be associated with functional differences in regions related to focused attention, executive control, and emotional awareness and regulation.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (10.1007/s12671-018-0928-x) contains supplementary material, which is available to authorized users.</P>

Muscle Functional MRI of Exercise-Induced Rotator Cuff Muscles

Tawara, Noriyuki,Nishiyama, Atsushi Korean Society of Magnetic Resonance in Medicine 2021 Investigative Magnetic Resonance Imaging Vol.25 No.1

The aim of this study was to provide a new assessment of rotator cuff muscle activity. Eight male subjects (24.7 ± 3.2 years old,171.2 ± 9.8 cm tall, and weighing 63.8 ± 11.9 kg) performed the study exercises. The subjects performed 10 sets of the exercise while fixing the elbow at 90 degrees flexure and lying supine on a bed. One exercise set consisted of the subject performing external shoulder rotation 50 times using training equipment. Two imaging protocols were employed: (a) true fast imaging with steady precession (TrueFISP) at an acquisition time of 12 seconds and (b) multi-shot spin-echo echo-planar imaging (MSSE-EPI) at an acquisition time of 30 seconds for one echo. The main method of assessing rotator cuff muscle activity was functional T2 mapping using ultrafast imaging (fast-acquired muscle functional MRI [fast-mfMRI]). Fast-mfMRI enabled real-time imaging for the identification and evaluation of the degree of muscle activity induced by the exercise. Regions of interest were set at several places in the musculus subscapularis (sub), musculus supraspinatus (sup), musculus teres minor (ter), and deltoid muscle (del). We used the MR signal of the images and transverse relaxation time (T2) for comparison. Most of the TrueFISP signal was not changed by exercise and there was no significant difference from the resting values. Only the T2 in the musculus teres minor was increased after one set and the change were seen on the T2 images. Additionally, except for those after one and two sets, the changes in T2 were significant compared to those at rest (P < 0.01). We also demonstrated identify and visualize the extent to which muscles involved in muscle activity by exercise. In addition, we showed that muscle activity in a region such as a shoulder, which is susceptible to B0 inhomogeneity, could be easily detected using this technique.

Aberrant Resting-state Functional Connectivity in Complex Regional Pain Syndrome: A Network-based Statistics Analysis

홍혜진,서채원,Eun Namgung,하은지,이수지,김래영,송유미,오소현,In Kyoon Lyoo,Hyeonseok Jeong,윤수정 한국뇌신경과학회 2023 Experimental Neurobiology Vol.32 No.2

Complex regional pain syndrome (CRPS) is a chronic neuropathic pain disorder. Pain catastrophizing, characterized by magnification, rumination,and helplessness, increases perceived pain intensity and mental distress in CRPS patients. As functional connectivity patterns in CRPS remainlargely unknown, we aimed to investigate functional connectivity alterations in CRPS patients and their association with pain catastrophizing usinga whole-brain analysis approach. Twenty-one patients with CRPS and 49 healthy controls were included in the study for clinical assessment andresting-state functional magnetic resonance imaging. Between-group differences in whole-brain functional connectivity were examined througha Network-based Statistics analysis. Associations between altered functional connectivity and the extent of pain catastrophizing were also assessedin CRPS patients. Relative to healthy controls, CRPS patients showed higher levels of functional connectivity in the bilateral somatosensory subnetworks(components 1~2), but lower functional connectivity within the prefronto-posterior cingulate (component 3), prefrontal (component 4),prefronto-parietal (component 5), and thalamo-anterior cingulate (component 6) subnetworks (p<0.05, family-wise error corrected). Higher levelsof functional connectivity in components 1~2 (β=0.45, p=0.04) and lower levels of functional connectivity in components 3~6 (β=-0.49, p=0.047)were significantly correlated with higher levels of pain catastrophizing in CRPS patients. Higher functional connectivity in the somatosensorysubnetworks implicating exaggerated pain perception and lower functional connectivity in the prefronto-parieto-cingulo-thalamic subnetworksindicating impaired cognitive-affective pain processing may underlie pain catastrophizing in CRPS.

Brain Mapping Using Neuroimaging

Tae, Woo-Suk,Kang, Shin-Hyuk,Ham, Byung-Joo,Kim, Byung-Jo,Pyun, Sung-Bom Korean Society of Microscopy 2016 Applied microscopy Vol.46 No.4

Mapping brain structural and functional connections through the whole brain is essential for understanding brain mechanisms and the physiological bases of brain diseases. Although region specific structural or functional deficits cause brain diseases, the changes of interregional connections could also be important factors of brain diseases. This review will introduce common neuroimaging modalities, including structural magnetic resonance imaging (MRI), functional MRI (fMRI), diffusion tensor imaging, and other recent neuroimaging analyses methods, such as voxel-based morphometry, cortical thickness analysis, local gyrification index, and shape analysis for structural imaging. Tract-Based Spatial Statistics, TRActs Constrained by UnderLying Anatomy for diffusion MRI, and independent component analysis for fMRI also will also be introduced.

Classification of Magnetic Resonance Brain Images using Bi-dimensional Empirical Mode Decomposition and Autoregressive Model

Omkishor Sahu,Vijay Anand,Vivek Kanhangad,Ram Bilas Pachori 대한의용생체공학회 2015 Biomedical Engineering Letters (BMEL) Vol.5 No.4

Purpose Automated classification of brain magnetic resonance(MR) images has been an extensively researched topic inbiomedical image processing. In this work, we propose anew approach for classifying normal and abnormal brain MRimages using bi-dimensional empirical mode decomposition(BEMD) and autoregressive (AR) model. Methods In our approach, brain MR image is decomposedinto four intrinsic mode functions (IMFs) using BEMD andAR coefficients from multiple IMFs are concatenated toform a feature vector. Finally a binary classifier, least-squaressupport vector machine (LS-SVM), is employed to discriminatebetween normal and abnormal brain MR images. Results The proposed technique achieves 100% classificationaccuracy using second-order AR model with linear andradial basis function (RBF) as kernels in LS-SVM. Conclusions Experimental results confirm that the performanceof the proposed method is quite comparable with the existingresults. Specifically, the presented approach outperformsone-dimensional empirical mode decomposition (1D-EMD)based classification of brain MR images.