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Full-Text Articles in Engineering
Investigations Of Anatomical Connectivity In The Internal Capsule Of Macaques With Diffusion Magnetic Resonance Imaging, Kyle Andrew Ignatius Taljan
Investigations Of Anatomical Connectivity In The Internal Capsule Of Macaques With Diffusion Magnetic Resonance Imaging, Kyle Andrew Ignatius Taljan
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Understanding anatomical connectivity is crucial for improving outcomes of deep brain stimulation surgery. Tractography is a promising method for noninvasively investigating anatomical connectivity, but connections between subcortical regions have not been closely examined by this method. As many connections to subcortical regions converge at the internal capsule (IC), we investigate the connectivity through the IC to three subcortical nuclei (caudate, lentiform nucleus, and thalamus) in 6 macaques. We show that a statistical correction for a known distance-related artifact in tractography results in large changes in connectivity patterns. Our results suggest that care should be taken in using tractography to assess …
Measurement Of White Matter Structure Changes In Amyotrophic Lateral Sclerosis Using Fractal Analysis, Zao Liu
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Amyotrophic lateral sclerosis (ALS) is recognized as a motor neuron disorder affecting the structure and function of the brain and neuromuscular system. Very little is known, however, that the nervous system degeneration is dependent on disease phenotypes of ALS. The purpose of this study was to determine the degree of brain white matter (WM) structure degeneration in four ALS patient groups characterized by their clinical signs and neuroimaging measurements. Fractal dimension (FD) of three-dimensional (3D) brain WM images was quantitatively analyzed to evaluate the WM structural complexity, including complexity levels of the WM skeleton, surface and general structures in ALS …
Evaluation Of Upper Motor Neuron Pathology In Amyotrophic Lateral Sclerosis By Mri;Towards Identifying Noninvasive Biomarkers Of The Disease, Venkateswaran Rajagopalan
Evaluation Of Upper Motor Neuron Pathology In Amyotrophic Lateral Sclerosis By Mri;Towards Identifying Noninvasive Biomarkers Of The Disease, Venkateswaran Rajagopalan
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Amyotrophic lateral sclerosis (ALS) is the commonest adult motor neuron disease (MND) which causes progressive muscle paralysis and death usually within 5 years of symptom onset. As a result, only ╠â30,000 individuals in the United States are afflicted at any one time even though 5,000 or more individuals are diagnosed yearly. The diagnosis of ALS requires evidence of degeneration in upper motor neurons (UMNs) in the brain and in lower motor neurons (LMNs) that exit the brainstem and spinal cord to innervate skeletal muscles. Diagnosis can be incorrect or delayed when disease is early or atypical because non-invasive objective tests …
Altered Cortico-Cortical Brain Connectivity During Muscle Fatigue, Zhiguo Jiang
Altered Cortico-Cortical Brain Connectivity During Muscle Fatigue, Zhiguo Jiang
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Traditional brain activation studies using neuroimaging such as functional magnetic imaging (fMRI) have shown that muscle fatigue at submaximal intensity level is associated with increased brain activity in various cortical regions from low- to high-order motor centers. However, how these areas might interact remain unclear since previous activation studies related to motor control could not reveal information of between-area interaction. This issue can be addressed by evaluating brain activation data using the framework of connectivity analysis. Three types of brain connectivity, functional connectivity (FC), effective connectivity (EC) and structural connectivity (SC) have been examined to investigate the effect of voluntary …