Delineating the Decussating Dentato-rubro-thalamic Tract and Its Connections in Humans Using Diffusion Spectrum Imaging Techniques

BackgroundThe relationship between white-matter tracts and executive functions (EF) in attention deficit hyperactivity disorder (ADHD) has not been well studied and previous studies mainly focused on frontostriatal (FS) tracts. The authors explored the microstructural property of several fibre tracts hypothesized to be involved in EF, to correlate their microstructural property with EF, and to explore whether such associations differ between ADHD and typically developing (TD) youths.MethodWe assessed 45 youths with ADHD and 45 individually matched TD youths with a computerized test battery for multiple dimensions of EF. From magnetic resonance imaging, FS tract, superior longitudinal fasciculus (SLF), arcuate fasciculus (AF) and cingulum bundle (CB) were reconstructed by diffusion spectrum imaging tractography. The generalized fractional anisotropy (GFA) values of white-matter tracts were computed to present microstructural property of each tract.ResultsWe found lower GFA in the left FS tract, left SLF, left AF and right CB, and poorer performance in set-shifting, sustained attention, cognitive inhibition and visuospatial planning in ADHD than TD. The ADHD and TD groups demonstrated different association patterns between EF and fibre tract microstructural property. Most of the EF were associated with microstructural integrity of the FS tract and CB in TD youths, while with that of the FS tract, SLF and AF in youths with ADHD.ConclusionsOur findings support that the SLF, AF and CB also involve in a wide range of EF and that the main fibre tracts involved in EF are different in youths with ADHD.

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Microstructural Description of Cerebral Tissues from Diffusion Spectrum Imaging Data

2014 IEEE International Conference on Healthcare Informatics ◽

10.1109/ichi.2014.68 ◽

2014 ◽

Author(s):

Lorenza Brusini ◽

Mauro Zucchelli ◽

Cristina Granziera ◽

Gloria Menegaz

Keyword(s):

Imaging Data ◽

Diffusion Spectrum Imaging ◽

Spectrum Imaging

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Dependence of Scan Parameters on Nerve Fiber Crossing Depiction in Diffusion Spectrum Imaging in Clinical Practice

Journal of Computer Assisted Tomography ◽

10.1097/rct.0000000000000715 ◽

2018 ◽

Vol 42 (4) ◽

pp. 522-526

Author(s):

Minghui Tang ◽

Kazuya Oshinomi ◽

Kinya Ishizaka ◽

Khin Khin Tha ◽

Toru Yamamoto

Keyword(s):

Clinical Practice ◽

Nerve Fiber ◽

Diffusion Spectrum Imaging ◽

Spectrum Imaging

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Signal propagation via cortical hierarchies

Network Neuroscience ◽

10.1162/netn_a_00153 ◽

2020 ◽

Vol 4 (4) ◽

pp. 1072-1090 ◽

Cited By ~ 3

Author(s):

Bertha Vézquez-Rodríguez ◽

Zhen-Qi Liu ◽

Patric Hagmann ◽

Bratislav Misic

Keyword(s):

Shortest Paths ◽

Signal Propagation ◽

Brain Regions ◽

Hierarchical Organization ◽

Attention Networks ◽

Diffusion Spectrum Imaging ◽

Cortical Hierarchy ◽

Spectrum Imaging ◽

Structural Networks ◽

The Brain

The wiring of the brain is organized around a putative unimodal-transmodal hierarchy. Here we investigate how this intrinsic hierarchical organization of the brain shapes the transmission of information among regions. The hierarchical positioning of individual regions was quantified by applying diffusion map embedding to resting-state functional MRI networks. Structural networks were reconstructed from diffusion spectrum imaging and topological shortest paths among all brain regions were computed. Sequences of nodes encountered along a path were then labeled by their hierarchical position, tracing out path motifs. We find that the cortical hierarchy guides communication in the network. Specifically, nodes are more likely to forward signals to nodes closer in the hierarchy and cover a range of unimodal and transmodal regions, potentially enriching or diversifying signals en route. We also find evidence of systematic detours, particularly in attention networks, where communication is rerouted. Altogether, the present work highlights how the cortical hierarchy shapes signal exchange and imparts behaviorally relevant communication patterns in brain networks.

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Energy Filtering and Spectrum Imaging of Polymers

Microscopy and Microanalysis ◽

10.1017/s1431927600038071 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 1116-1117

Author(s):

A. Aitouchen ◽

J. Taylor ◽

P. Crozier ◽

M. Libera

Keyword(s):

Imaging Techniques ◽

Polymeric Materials ◽

Chemical Imaging ◽

Polymer Particle ◽

Initial Image ◽

Image Region ◽

Energy Filtering ◽

Spectrum Imaging ◽

Field Imaging ◽

Tem Grid

Chemical imaging of polymeric materials is attractive, because of the inherently poor contrast typically afforded by multiphase amorphous polymers in bright-field imaging techniques. Spectrum imaging and energy-filtering approaches are being increasing applied to polymeric materials (1,2, 3).One recent example from the Stevens group using a Philips CM20 FEG TEM/STEM interfaced to an EmiSpec Vision data acquisition/control system and a Gatan 666 PEELS spectrometer is presented in figure 1. The specimen is a PVP sphere on a holey-carbon TEM grid. The specimen was cooled to approximately -125 °C in a single-tilt cryo stage. Drift correction was implemented by collecting HAADF STEM images from the sub-image region indicated by the dashed white box at periodic intervals. Based on an autocorrelation with the initial image, electronic shifts where imposed to correct for drift. A 3-D spectrum dataset was generated from the 70 x 70 pixel box around the polymer particle at an interpixel spacing of 5 nm and a pixel dwell time of 1.5 sec.

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