Two‐dimensional population map of cortical connections in the human internal capsule

Zarei, Mojtaba; Johansen‐Berg, Heidi; Jenkinson, Mark; Ciccarelli, Olga; Thompson, Alan J.; Matthews, Paul M.

doi:10.1002/jmri.20810

Cited by 56 publications

(53 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First of all, the results confirm previous findings that place the PT of the primary motor and primary sensory system into the posterior limb of the internal capsule, in humans as well as in monkeys [6,28,29]. Secondly, we observed a rotation of the PT on its way from the cortex through the semioval center and internal capsule into the brainstem.…”

Section: Discussionsupporting

confidence: 90%

Topographical Organization of the Pyramidal Fiber System - Diffusion Tensor MRI of the Human and Rhesus Monkey Brain

Hofer¹,

Frahm²

2009

TOMIJ

View full text Add to dashboard Cite

Abstract:The fibers of the pyramidal tract (PT) that connect the precentral and postcentral gyrus with the spinal cord are organized in a topological manner. However, their exact arrangement and orientation in the internal capsule is still a matter of debate. Here, we applied magnetic resonance diffusion tensor imaging and tract tracing techniques to determine and compare the pyramidal fibers from the primary motor and somatosensory system in humans and rhesus monkeys in vivo. The results demonstrate that the pyramidal systems of the human and monkey brain differ in their orientation at the level of the internal capsule, whereas track orientations in the gyrus and brainstem appear similar. In the monkey internal capsule the somatotopic arrangement of PT fibers from the upper and lower extremities form an angle with the left-right axis of 146° ± 23° (n=4). Thus, fibers from lateral areas of the gyrus are located more anterior-medial to fibers from medial cortical areas. In contrast, in humans the angle is only 50° ± 16° (n=9) yielding a more anterior-lateral orientation of PT fibers along the short axis of the internal capsule. These species dependencies may possibly be due to structural constraints of the smaller and differently shaped monkey brain.

show abstract

Section: Discussionsupporting

confidence: 90%

Topographical Organization of the Pyramidal Fiber System - Diffusion Tensor MRI of the Human and Rhesus Monkey Brain

Hofer¹,

Frahm²

2009

TOMIJ

View full text Add to dashboard Cite

show abstract

“…23,24 We did not find any significant differences in the DTI metrics between SCI patients and controls in these structures. Freund et al 14 and Guleria et al 15 showed reduced FA values but unchanged MDs in the PLIC after SCI compared with healthy subjects.…”

Section: Discussionmentioning

confidence: 49%

Clinical correlates of cerebral diffusion tensor imaging findings in chronic traumatic spinal cord injury

et al. 2014

View full text Add to dashboard Cite

Study design: Prospective clinical case-control study. Objectives: The aim of this study was to use diffusion tensor imaging (DTI) to assess the state of cerebral white matter tracts after spinal cord injury (SCI). The DTI metrics were evaluated in relation to neurological deficits and to the size and level of the spinal cord lesions. Setting: Tampere University Hospital, Tampere, Finland. Methods: Thirty-four patients (n ¼ 34) with clinically complete and incomplete SCI were evaluated using the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). DTI metrics (fractional anisotropy (FA) and apparent diffusion coefficient (ADC)) were calculated for multiple levels along the course of the corticospinal tract. The state of the spinal cord after injury was assessed using conventional magnetic resonance imaging (MRI). DTI parameters were compared with 40 orthopedically injured control subjects. Results: Statistically significant differences in the DTI values between patients and controls were detected in the posterior area of the centrum semiovale. In this area, the FA values were lower in the patients compared with controls (P ¼ 0.008). For patients with clinically complete injury, the difference was even more significant (P ¼ 0.0005). Motor and sensory scores of the ISNCSCI correlated positively with FA and negatively with ADC values of the centrum semiovale. A moderate association was observed between the macroscopic changes in the spinal cord and the DTI abnormalities in the centrum semiovale. Conclusion: In patients with chronic SCI, DTI changes can be observed in the cerebral white matter. These alterations are associated with the clinical state of the patients.

show abstract

“…This second post hoc analysis revealed a positive correlation between axial diffusivity in the posterior limb of the internal capsule, which maps to the posterior limb of the internal capsule to motor and premotor cortices (Zarei et al, 2007), and response time on the Grooved Pegboard test in veterans with predicted GB/GF exposure. Although there have been reports of psychomotor slowing in GW veterans with predicted GB/GF exposure (Proctor et al, 2006) and in victims of the Tokyo subway sarin attack (Miyaki et al, 2005;Yokoyama et al, 1998), it is noteworthy that we did not find any evidence of psychomotor slowing in the current cohort of GW veterans with predicted GB/GF exposure (Chao et al, 2011).…”

Section: Va Author Manuscriptmentioning

confidence: 86%

“…Because a previous study reported a positive correlation between axial diffusivity in the posterior limb of the internal capsule, which tractography studies have mapped to the posterior limb of the internal capsule to motor and premotor cortices (Zarei et al, 2007), with psychomotor speed in patients with traumatic brain injury (Kinnunen et al, 2011), our finding of a trend for a positive association between axial diffusivity in GW veterans with predicted GB/GF exposure and performance on the Grooved Pegboard test prompted us to further examine axial diffusivity from the posterior limb of the internal capsule. Age was the only potentially confounding variable that was significantly associated performance on the Grooved Pegboard test (p < 0.001), as expected from the aging literature (Madden, 2001).…”

Section: Post Hoc Analysesmentioning

confidence: 99%

Effects of low-level sarin and cyclosarin exposure on white matter integrity in Gulf War Veterans

Chao

Buckley

2015

NeuroToxicology

View full text Add to dashboard Cite

Background-We previously found evidence of reduced gray and white matter volume in Gulf War (GW) veterans with predicted low-level exposure to sarin (GB) and cyclosarin (GF). Because loss of white matter tissue integrity has been linked to both gray and white matter atrophy, the current study sought to test the hypothesis that GW veterans with predicted GB/GF exposure have evidence of disrupted white matter microstructural integrity.Methods-Measures of fractional anisotropy and directional (i.e., axial and radial) diffusivity were assessed from the 4 T diffusion tensor images (DTI) of 59 GW veterans with predicted GB/GF exposure and 59 "matched" unexposed GW veterans (mean age: 48 ± 7 years). The DTI data were analyzed using regions of interest (ROI) analyses that accounted for age, sex, total brain gray and white matter volume, trauma exposure, posttraumatic stress disorder, current major depression, and chronic multisymptom illness status.Results-There were no significant group differences in fractional anisotropy or radial diffusivity. However, there was increased axial diffusivity in GW veterans with predicted GB/GF exposure compared to matched, unexposed veterans throughout the brain, including the temporal stem, corona radiata, superior and inferior (hippocampal) cingulum, inferior and superior frontooccipital fasciculus, internal and external capsule, and superficial cortical white matter blades. Post hoc analysis revealed significant correlations between higher fractional anisotropy and lower radial diffusivity with better neurobehavioral performance in unexposed GW veterans. In contrast, only Conflict of interestThe authors declare that there are no conflicts of interest. Transparency documentThe Transparency document associated with this article can be found in the online version. U.S. Department of Veterans Affairs VA Author ManuscriptVA Author Manuscript VA Author Manuscript increased axial diffusivity in posterior limb of the internal capsule was associated with better psychomotor function in GW veterans with predicted GB/GF exposure.Conclusions-The finding that increased axial diffusivity in a region of the brain that contains descending corticospinal fibers was associated with better psychomotor function and the lack of significant neurobehavioral deficits in veterans with predicted GB/GF exposure hint at the possibility that the widespread increases in axial diffusivity that we observed in GW veterans with predicted GB/GF exposure relative to unexposed controls may reflect white matter reorganization after brain injury (i.e., exposure to GB/GF).

show abstract

Two‐dimensional population map of cortical connections in the human internal capsule

Cited by 56 publications

References 56 publications

Topographical Organization of the Pyramidal Fiber System - Diffusion Tensor MRI of the Human and Rhesus Monkey Brain

Topographical Organization of the Pyramidal Fiber System - Diffusion Tensor MRI of the Human and Rhesus Monkey Brain

Clinical correlates of cerebral diffusion tensor imaging findings in chronic traumatic spinal cord injury

Effects of low-level sarin and cyclosarin exposure on white matter integrity in Gulf War Veterans

Contact Info

Product

Resources

About