Medicine and Health Sciences Commons^™

Clinical Applications Of Magnetic Resonance Imaging Based Functional And Structural Connectivity, Chengyuan Wu, Francisca Ferreira, Michael Fox, Noam Harel, Jona Hattangadi-Gluth, Andreas Horn, Saad Jbabdi, Joshua Kahan, Ashwini Oswal, Sameer A Sheth, Yanmei Tie, Vejay Vakharia, Ludvic Zrinzo, Harith Akram

Department of Neurosurgery Faculty Papers

Advances in computational neuroimaging techniques have expanded the armamentarium of imaging tools available for clinical applications in clinical neuroscience. Non-invasive, in vivo brain MRI structural and functional network mapping has been used to identify therapeutic targets, define eloquent brain regions to preserve, and gain insight into pathological processes and treatments as well as prognostic biomarkers. These tools have the real potential to inform patient-specific treatment strategies. Nevertheless, a realistic appraisal of clinical utility is needed that balances the growing excitement and interest in the field with important limitations associated with these techniques. Quality of the raw data, minutiae of the …

Alterations In Functional Connectivity Measured By Functional Magnetic Resonance Imaging And The Relationship With Heart Rate Variability In Subjects After Performing Orgasmic Meditation: An Exploratory Study, Andrew B. Newberg, Nancy Wintering, Chloe Hriso, Faezeh Vedaei, Marie Stoner, Reneita Ross

Department of Radiology Faculty Papers

Background: We measured changes in resting brain functional connectivity, with blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI), associated with a creative meditation practice that is augmented by clitoral stimulation and is designed to not only achieve a spiritual experience but to help individuals manage their most intimate personal relationships. Briefly, the meditative state is attained by both the male and female participants while the male stimulates the woman's clitoris. The goal of this practice, called orgasmic meditation (OM), according to the practitioners is not sexual, but to use the focus on clitoral stimulation to facilitate a meditative …

The Functional And Structural Consequences Of Aberrant Microglial Activity In Major Depressive Disorder, Jasmine D. Cakmak

Electronic Thesis and Dissertation Repository

Major depressive disorder (MDD) is a highly debilitating neuropsychiatric illness which has been linked with increases in both peripheral and central inflammation, as well as with changes in connectivity. Although countless studies have investigated these two topics, the relationship between neuroinflammation and functional/structural connectivity has not been explored. Using [¹⁸F]FEPPA PET imaging, we measured translocator protein-related (TSPO) microglial activity in the subgenual anterior cingulate cortex (sgACC) and insula and confirmed significantly increased [¹⁸F]FEPPA uptake in depressed patients (N=12) compared to healthy controls (N=23). Using a seed-based ROI analysis of fMRI data, we found that patients show …

Theta-Burst Stimulation Entrains Frequency-Specific Oscillatory Responses., Ethan A. Solomon, Michael R. Sperling, Ashwini D. Sharan, Paul A. Wanda, Deborah F. Levy, Anastasia Lyalenko, Isaac Pedisich, Daniel S. Rizzuto, Michael J. Kahana

Department of Neurology Faculty Papers

BACKGROUND: Brain stimulation has emerged as a powerful tool in human neuroscience, becoming integral to next-generation psychiatric and neurologic therapeutics. Theta-burst stimulation (TBS), in which electrical pulses are delivered in rhythmic bouts of 3-8 Hz, seeks to recapitulate neural activity seen endogenously during cognitive tasks. A growing literature suggests that TBS can be used to alter or enhance cognitive processes, but little is known about how these stimulation events influence underlying neural activity.

OBJECTIVE: Our study sought to investigate the effect of direct electrical TBS on mesoscale neural activity in humans by asking (1) whether TBS evokes persistent theta oscillations …

The Functional Connectivity Of The Auditory Cortex In Autism Spectrum Disorder, Katherine Wilson

Honors Theses

Disturbance of the auditory cortex in Autism Spectrum Disorder (ASD) is well known as well as its influence on hearing. Functional connectivity within the brain is also known to be affected by ASD. However, functional connectivity of the auditory cortex in ASD has yet to be studied. In this study, using resting-state functional magnetic resonance imaging data from the Autism Brain Imaging Data Exchange (ABIDE), functional connectivity of the auditory cortex was examined by comparing 68 individuals with ASD and 75 individuals with ASD. Four brain regions showed smaller functional connectivity to and from the auditory cortex; the occipital cortex, …

Functional Connectivity Of The Inferior Frontal Gyrus In Autism Spectrum Disorders, Emma Miller

Honors Theses

ABSTRACT

The American Speech-Language-Hearing Association defines Autism Spectrum Disorder (ASD) as a “neurodevelopmental disorder characterized by deficits in social communication and social interaction” which is heavily impacts language abilities. There is an abundance of research on the neurological aspects of the disorder, which appear to have major differences of activation and functionality when compared to typically developing peers. Specifically, in the left inferior frontal gyrus (IFG), a key language region of the brain, functional connectivity levels tend to be significantly less in ASD groups. This study recognizes these trends and aims to expand the research by locating specific functional connections …

Muting, Not Fragmentation, Of Functional Brain Networks Under General Anesthesia, Corson N. Areshenkoff, Joseph Y. Nashed, R. Matthew Hutchison, Melina Hutchison, Ron Levy, Douglas J. Cook, Ravi S. Menon, Stefan Everling, Jason P. Gallivan

Brain and Mind Institute Researchers' Publications

© 2021 Changes in resting-state functional connectivity (rs-FC) under general anesthesia have been widely studied with the goal of identifying neural signatures of consciousness. This work has commonly revealed an apparent fragmentation of whole-brain network structure during unconsciousness, which has been interpreted as reflecting a break-down in connectivity and a disruption of the brain's ability to integrate information. Here we show, by studying rs-FC under varying depths of isoflurane-induced anesthesia in nonhuman primates, that this apparent fragmentation, rather than reflecting an actual change in network structure, can be simply explained as the result of a global reduction in FC. Specifically, …

Allocentric Representation In The Human Amygdala And Ventral Visual Stream, Hallvard Røe Evensmoen, Lars M. Rimol, Anderson M. Winkler, Richard Betzel, Tor Ivar Hansen

School of Medicine Publications and Presentations

The hippocampus and the entorhinal cortex are considered the main brain structures for allocentric representation of the external environment. Here, we show that the amygdala and the ventral visual stream are involved in allocentric representation. Thirty-one young men explored 35 virtual environments during high-resolution functional magnetic resonance imaging (fMRI) of the medial temporal lobe (MTL) and were subsequently tested on recall of the allocentric pattern of the objects in each environment-in other words, the positions of the objects relative to each other and to the outer perimeter. We find increasingly unique brain activation patterns associated with increasing allocentric accuracy in …

Resting Cerebral Oxygen Metabolism Exhibits Archetypal Network Features, Nicholas A. Hubbard, Monroe P. Turner, Kevin R. Sitek, Kathryn L. West, Jakub R. Kaczmarzyk, Lyndahl Himes, Binu P. Thomas, Hanzhang Lu, Bart Rypma

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

Standard magnetic resonance imaging approaches offer high-resolution but indirect measures of neural activity, limiting understanding of the physiological processes associated with imaging findings. Here, we used calibrated functional magnetic resonance imaging during the resting state to recover low-frequency fluctuations of the cerebral metabolic rate of oxygen (CMRO2). We tested whether functional connections derived from these fluctuations exhibited organization properties similar to those established by previous standard functional and anatomical connectivity studies. Seventeen participants underwent 20 min of resting imaging during dual-echo, pseudocontinuous arterial spin labeling, and blood-oxygen-level dependent (BOLD) signal acquisition. Participants also underwent a 10 min normocapnic and hypercapnic …

Effects Of Tdcs Dose And Electrode Montage On Regional Cerebral Blood Flow And Motor Behavior, Anant B. Shinde, Karl D. Lerud, Fanny Munsch, David C. Alsop, Gottfried Schlaug

Psychological and Brain Sciences Faculty Publication Series

5, 6, 7, 8) in the hypothesized brain regions. Violations to consecutiveness elicited brain activity in the right inferior frontal gyrus (IFG) and the supplementary motor area (SMA). In contrast, no such activation was observed in the auditory cortex, despite violations in voice identity recruiting strong activity in that region. Also, no activation was observed in the inferior parietal lobule, despite a robust effect of orderedness observed in that brain region. These findings indicate that listening to counting sequences do not automatically elicit sensory or magnitude codes but suggest that the precise increments in the sequence are tracked by the …

Experience-Dependent Plasticitiy Of Functional Connectivity In Human Visual Cortex Following Central Vision Loss, Leland Lanelle Fleming

All ETDs from UAB

The human brain is shaped by a dynamic interplay between innate factors and life experiences. Neuroscience has long grappled with understanding this relationship, particularly with regard to how changes in experience impact the brain during adulthood. This question is especially important in the context of macular degeneration, a disease that causes significant visual impairment and drastically alters day-to-day visual experiences for individuals afflicted by the disease. Specifically, people with macular degeneration lose the ability to use vision in the center of the visual field, the region of the retina with the highest spatial resolution. Subsequently, these individuals must rely on …