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3. The Function Biomedical Informatics Research Network Data Repository.

Author

Keator, David B, van Erp, Theo GM, Turner, Jessica A, Glover, Gary H, Mueller, Bryon A, Liu, Thomas T, Voyvodic, James T, Rasmussen, Jerod, Calhoun, Vince D, Lee, Hyo Jong, Toga, Arthur W, McEwen, Sarah, Ford, Judith M, Mathalon, Daniel H, Diaz, Michele, O'Leary, Daniel S, Jeremy Bockholt, H, Gadde, Syam, Preda, Adrian, Wible, Cynthia G, Stern, Hal S, Belger, Aysenil, McCarthy, Gregory, Ozyurt, Burak, Potkin, Steven G, and FBIRN

Subjects
FBIRN, Humans, Magnetic Resonance Imaging, Information Dissemination, Psychotic Disorders, Schizophrenia, Research, Biomedical Research, Reference Values, Medical Informatics, Databases, Factual, Adolescent, Adult, Aged, Middle Aged, Female, Male, Young Adult, Neuroimaging, Healthy Volunteers, Clinical Research, Mental Health, Networking and Information Technology R&D (NITRD), Neurosciences, Bioengineering, Neurological, Medical and Health Sciences, Psychology and Cognitive Sciences, Neurology & Neurosurgery
Abstract

The Function Biomedical Informatics Research Network (FBIRN) developed methods and tools for conducting multi-scanner functional magnetic resonance imaging (fMRI) studies. Method and tool development were based on two major goals: 1) to assess the major sources of variation in fMRI studies conducted across scanners, including instrumentation, acquisition protocols, challenge tasks, and analysis methods, and 2) to provide a distributed network infrastructure and an associated federated database to host and query large, multi-site, fMRI and clinical data sets. In the process of achieving these goals the FBIRN test bed generated several multi-scanner brain imaging data sets to be shared with the wider scientific community via the BIRN Data Repository (BDR). The FBIRN Phase 1 data set consists of a traveling subject study of 5 healthy subjects, each scanned on 10 different 1.5 to 4 T scanners. The FBIRN Phase 2 and Phase 3 data sets consist of subjects with schizophrenia or schizoaffective disorder along with healthy comparison subjects scanned at multiple sites. In this paper, we provide concise descriptions of FBIRN's multi-scanner brain imaging data sets and details about the BIRN Data Repository instance of the Human Imaging Database (HID) used to publicly share the data.

Published
2016

5. Effect of wearing a face mask on fMRI BOLD contrast

Author

Christine S.W. Law, Patricia S. Lan, and Gary H. Glover

Subjects
fMRI, BOLD contrast, Mask, Facial covering, COVID-19, SARS-CoV2, Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571
Abstract

International spread of the coronavirus SARS-CoV-2 has prompted many MRI scanning facilities to require scan subjects to wear a facial covering (“mask”) during scanning as a precaution against transmission of the virus. Because wearing a mask mixes expired air with the subject's inspired air stream, the concentration of inspired carbon dioxide [CO2] is elevated, resulting in mild hypercapnia. Changes in the inspired gas mixture have been demonstrated to alter R2*-weighted Blood Oxygen Dependent (BOLD) contrast. In this study, we investigate a potential for face masking to alter BOLD contrast during a sensory-motor task designed to activate visual, auditory, and sensorimotor cortices in 8 subjects. We utilize a nasal cannula to supply air to the subject wearing a surgical mask in on-off blocks of 90s to displace expired CO2, while the subject performs the sensory-motor task. While only a small fraction (2.5%) of the sensory-motor task activation is related to nasal air modulation, a 30.0% change in gray matter BOLD signal baseline is found due to air modulation. Repeating the scan with mask removed produces a small subject-specific bias in BOLD baseline signal from nasal air supply, which may be due to cognitive influence of airflow or cannula-induced hypoxia. Measurements with capnography demonstrate wearing a mask induces an average increase in ETCO2 of 7.4%. Altogether, these results demonstrate that wearing a face mask during gradient-echo fMRI can alter BOLD baseline signal but minimally affects task activation.

Published
2021
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10. Dynamic functional connectivity: Promise, issues, and interpretations

Author

Hutchison, R. Matthew, Womelsdorf, Thilo, Allen, Elena A., Bandettini, Peter A., Calhoun, Vince D., Corbetta, Maurizio, Della Penna, Stefania, Duyn, Jeff H., Glover, Gary H., Gonzalez-Castillo, Javier, Handwerker, Daniel A., Keilholz, Shella, Kiviniemi, Vesa, Leopold, David A., de Pasquale, Francesco, Sporns, Olaf, Walter, Martin, and Chang, Catie

Published
2013
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34. Investigating mechanisms of fast BOLD responses: The effects of stimulus intensity and of spatial heterogeneity of hemodynamics

Author

Jonathan R. Polimeni, Jingyuan E. Chen, Bruce R. Rosen, Nina E. Fultz, Gary H. Glover, and Laura D. Lewis

Subjects
Adult, Male, Brain activity and meditation, Haemodynamic response, Computer science, Cognitive Neuroscience, media_common.quotation_subject, Neurosciences. Biological psychiatry. Neuropsychiatry, Stimulus (physiology), computer.software_genre, Somatosensory system, behavioral disciplines and activities, Young Adult, Task intensity, Voxel, Fast fMRI, Canonical model, Humans, Contrast (vision), Resting state, Nonlinearity, Visual Cortex, media_common, Brain Mapping, Resting state fMRI, Hemodynamic response function, High spatial resolution, Hemodynamics, Middle Aged, Magnetic Resonance Imaging, Neurology, Female, Neuroscience, computer, RC321-571
Abstract

Recent studies have demonstrated that fast fMRI can track neural activity well above the temporal limit predicted by the canonical hemodynamic response model. While these findings are promising, the biophysical mechanisms underlying these fast fMRI phenomena remain underexplored. In this study, we discuss two aspects of the hemodynamic response, complementary to several existing hypotheses, that can accommodate faster fMRI dynamics beyond those predicted by the canonical model. First, we demonstrate, using both visual and somatosensory paradigms, that the timing and shape of hemodynamic response functions (HRFs) vary across graded levels of stimulus intensity-with lower-intensity stimulation eliciting faster and narrower HRFs. Second, we show that as the spatial resolution of fMRI increases, voxel-wise HRFs begin to deviate from the canonical model, with a considerable portion of voxels exhibiting faster temporal dynamics than predicted by the canonical HRF. Collectively, both stimulus/task intensity and image resolution can affect the sensitivity of fMRI to fast brain activity, which may partly explain recent observations of fast fMRI signals. It is further noteworthy that, while the present investigations focus on fast neural responses, our findings suggest that a revised hemodynamic model may benefit the many fMRI studies using paradigms with wide ranges of contrast levels (e.g., resting or naturalistic conditions) or with modern, high-resolution MR acquisitions.

Published
2021

45. Effect of Wearing a Face Mask on fMRI BOLD Contrast

Author

Patricia S. Lan, Christine S. Law, and Gary H. Glover

Subjects
Masking (art), Audiology, medicine.disease_cause, Signal, 0302 clinical medicine, Technical Note, Contrast (vision), Gray Matter, facial covering, media_common, Capnography, medicine.diagnostic_test, 05 social sciences, fMRI, Masks, Magnetic Resonance Imaging, Neurology, Sensorimotor Cortex, medicine.symptom, Nasal cannula, Hypercapnia, psychological phenomena and processes, circulatory and respiratory physiology, Adult, medicine.medical_specialty, Cognitive Neuroscience, media_common.quotation_subject, behavioral disciplines and activities, 050105 experimental psychology, lcsh:RC321-571, 03 medical and health sciences, Young Adult, BOLD contrast, medicine, Humans, 0501 psychology and cognitive sciences, lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry, business.industry, Functional Neuroimaging, COVID-19, Carbon Dioxide, respiratory tract diseases, mask, Surgical mask, Face (geometry), SARS-CoV2, business, human activities, 030217 neurology & neurosurgery, Psychomotor Performance
Abstract

Highlights • Wearing a surgical mask increases end tidal CO2 and causes mild hypercapnia. • Hypercapnia increases cerebral blood flow and baseline BOLD signal. • Wearing a mask causes insignificant change in task activation., International spread of the coronavirus SARS-CoV-2 has prompted many MRI scanning facilities to require scan subjects to wear a facial covering (“mask”) during scanning as a precaution against transmission of the virus. Because wearing a mask mixes expired air with the subject's inspired air stream, the concentration of inspired carbon dioxide [CO2] is elevated, resulting in mild hypercapnia. Changes in the inspired gas mixture have been demonstrated to alter R2*-weighted Blood Oxygen Dependent (BOLD) contrast. In this study, we investigate a potential for face masking to alter BOLD contrast during a sensory-motor task designed to activate visual, auditory, and sensorimotor cortices in 8 subjects. We utilize a nasal cannula to supply air to the subject wearing a surgical mask in on-off blocks of 90s to displace expired CO2, while the subject performs the sensory-motor task. While only a small fraction (2.5%) of the sensory-motor task activation is related to nasal air modulation, a 30.0% change in gray matter BOLD signal baseline is found due to air modulation. Repeating the scan with mask removed produces a small subject-specific bias in BOLD baseline signal from nasal air supply, which may be due to cognitive influence of airflow or cannula-induced hypoxia. Measurements with capnography demonstrate wearing a mask induces an average increase in ETCO2 of 7.4%. Altogether, these results demonstrate that wearing a face mask during gradient-echo fMRI can alter BOLD baseline signal but minimally affects task activation.

Published
2021

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