Biomedical Engineering and Bioengineering Commons^™

Neural Correlates Of Multisensory Integration For Feedback Stabilization Of The Wrist, Aaron J. Suminski, Raymond C. Doudlah, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Robust control of action relies on the ability to perceive, integrate, and act on information from multiple sensory modalities including vision and proprioception. How does the brain combine sensory information to regulate ongoing mechanical interactions between the body and its physical environment? Some behavioral studies suggest that the rules governing multisensory integration for action may differ from the maximum likelihood estimation rules that appear to govern multisensory integration for many perceptual tasks. We used functional magnetic resonance (MR) imaging techniques, a MR-compatible robot, and a multisensory feedback control task to test that hypothesis by investigating how neural mechanisms involved in …

Eeg And Fmri Coupling And Decoupling Based On Joint Independent Component Analysis (Jica), Nicholas Heugel, Scott A. Beardsley, Einat Liebenthal

Biomedical Engineering Faculty Research and Publications

Background

Meaningful integration of functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) requires knowing whether these measurements reflect the activity of the same neural sources, i.e., estimating the degree of coupling and decoupling between the neuroimaging modalities.

New method

This paper proposes a method to quantify the coupling and decoupling of fMRI and EEG signals based on the mixing matrix produced by joint independent component analysis (jICA). The method is termed fMRI/EEG-jICA.

Results

fMRI and EEG acquired during a syllable detection task with variable syllable presentation rates (0.25–3 Hz) were separated with jICA into two spatiotemporally distinct components, a primary …

Comparison Of Whole-Head Functional Near-Infrared Spectroscopy With Functional Magnetic Resonance Imaging And Potential Application In Pediatric Neurology, Julie C. Wagner, Anthony Zinos, Wei-Liang Chen, Lisa Conant, Marsha Malloy, Joseph Heffernan, Brendan Quirk, Jeffrey Sugar, Robert W. Prost, Julian B. Whelan, Scott A. Beardsley, Harry T. Whelan

Biomedical Engineering Faculty Research and Publications

Background

Changes in cerebral blood flow in response to neuronal activation can be measured by time-dependent fluctuations in hemoglobin species within the brain; this is the basis of functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS). There is a clinical need for portable neural imaging systems, such as fNIRS, to accommodate patients who are unable to tolerate an MR environment.

Objective

Our objective was to compare task-related full-head fNIRS and fMRI signals across cortical regions.

Methods

Eighteen healthy adults completed a same-day fNIRS-fMRI study, in which they performed right- and left-hand finger tapping tasks and a semantic-decision tones-decision …

Method For Spatial Overlap Estimation Of Electroencephalography And Functional Magnetic Resonance Imaging Responses, N. Heugel, E. Liebenthal, Scott A. Beardsley

Biomedical Engineering Faculty Research and Publications

Background

Simultaneous functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) measurements may represent activity from partially divergent neural sources, but this factor is seldom modeled in fMRI-EEG data integration.

New method

This paper proposes an approach to estimate the spatial overlap between sources of activity measured simultaneously with fMRI and EEG. Following the extraction of task-related activity, the key steps include, 1) distributed source reconstruction of the task-related ERP activity (ERP source model), 2) transformation of fMRI activity to the ERP spatial scale by forward modelling of the scalp potential field distribution and backward source reconstruction (fMRI source simulation) …

Alterations In Cortical Sensorimotor Connectivity Following Complete Cervical Spinal Cord Injury: A Prospective Resting-State Fmri Study, Akinwunmi Oni-Orisan, Mayank Kaushal, Wenjun Li, Jack Leschke, B. Douglas Ward, Aditya Vedantam, Benjamin Kalinosky, Matthew D. Budde, Brian D. Schmit, Shi-Jiang Li, Viashnavi Muqeet, Shekar N. Kurpad

Biomedical Engineering Faculty Research and Publications

Functional magnetic resonance imaging (fMRI) studies have demonstrated alterations during task-induced brain activation in spinal cord injury (SCI) patients. The interruption to structural integrity of the spinal cord and the resultant disrupted flow of bidirectional communication between the brain and the spinal cord might contribute to the observed dynamic reorganization (neural plasticity). However, the effect of SCI on brain resting-state connectivity patterns remains unclear. We undertook a prospective resting-state fMRI (rs-fMRI) study to explore changes to cortical activation patterns following SCI. With institutional review board approval, rs-fMRI data was obtained in eleven patients with complete cervical SCI (>2 years …

Comparison Of Randomized Multifocal Mapping And Temporal Phase Mapping Of Visual Cortex For Clinical Use, Yan Ma, B. Douglas Ward, Kristina M. Ropella, Edgar A. Deyoe

Biomedical Engineering Faculty Research and Publications

fMRI is becoming an important clinical tool for planning and guidance of surgery to treat brain tumors, arteriovenous malformations, and epileptic foci. For visual cortex mapping, the most popular paradigm by far is temporal phase mapping, although random multifocal stimulation paradigms have drawn increased attention due to their ability to identify complex response fields and their random properties. In this study we directly compared temporal phase and multifocal vision mapping paradigms with respect to clinically relevant factors including: time efficiency, mapping completeness, and the effects of noise. Randomized, multifocal mapping accurately decomposed the response of single voxels to multiple stimulus …

Within-Subject Joint Independent Component Analysis Of Simultaneous Fmri/Erp In An Auditory Oddball Paradigm, Jain Mangalathu-Arumana, Scott A. Beardsley, E. Liebenthal

Biomedical Engineering Faculty Research and Publications

The integration of event-related potential (ERP) and functional magnetic resonance imaging (fMRI) can contribute to characterizing neural networks with high temporal and spatial resolution. This research aimed to determine the sensitivity and limitations of applying joint independent component analysis (jICA) within-subjects, for ERP and fMRI data collected simultaneously in a parametric auditory frequency oddball paradigm. In a group of 20 subjects, an increase in ERP peak amplitude ranging 1–8 μV in the time window of the P300 (350–700 ms), and a correlated increase in fMRI signal in a network of regions including the right superior temporal and supramarginal gyri, was …

Design And Validation Of A Mr-Compatible Pneumatic Manipulandum, Aaron J. Suminski, Janice L. Zimbelman, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

The combination of functional MR imaging and novel robotic tools may provide unique opportunities to probe the neural systems underlying motor control and learning. Here, we describe the design and validation of a MR-compatible, 1 degree-of-freedom pneumatic manipulandum along with experiments demonstrating its safety and efficacy. We first validated the robot's ability to apply computer-controlled loads about the wrist, demonstrating that it possesses sufficient bandwidth to simulate torsional spring-like loads during point-to-point flexion movements. Next, we verified the MR-compatibility of the device by imaging a head phantom during robot operation. We observed no systematic differences in two measures of MRI …