Publications by authors named "Jeffrey Sugar"

Functional near infrared spectroscopy (fNIRS) and functional magnetic resonance imaging (fMRI) both measure the hemodynamic response, and so both imaging modalities are expected to have a strong correspondence in regions of cortex adjacent to the scalp. To assess whether fNIRS can be used clinically in a manner similar to fMRI, 22 healthy adult participants underwent same-day fMRI and whole-head fNIRS testing while they performed separate motor (finger tapping) and visual (flashing checkerboard) tasks. Analyses were conducted within and across subjects for each imaging approach, and regions of significant task-related activity were compared on the cortical surface.

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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.

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Similar to functional magnetic resonance imaging (fMRI), functional near-infrared spectroscopy (fNIRS) detects the changes of hemoglobin species inside the brain, but via differences in optical absorption. Within the near-infrared spectrum, light can penetrate biological tissues and be absorbed by chromophores, such as oxyhemoglobin and deoxyhemoglobin. What makes fNIRS more advantageous is its portability and potential for long-term monitoring.

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Postural orthostatic tachycardia syndrome (POTS) is a disabling condition characterized by orthostatic intolerance with tachycardia in the absence of drop-in blood pressure. A custom-built near-infrared spectroscopy device (NIRS) is applied to monitor the muscle oxygenation, noninvasively in patients undergoing incremental head-up tilt table (HUT). Subjects (6 POTS patients and 6 healthy controls) underwent 30 mins of 70°on a HUT.

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The oxygenation level of a tissue is an important marker of the health of the tissue and has a direct effect on performance. It has been shown that the blood flow to the paretic muscles of hemiparetic post-stroke patients is significantly reduced compared to non-paretic muscles. It is hypothesized that hemodynamic activity in paretic muscles is suppressed as compared to non-paretic muscles, and that oximetry can be used to measure this disparity in real-time.

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Objective: The authors demonstrate the value of reflective team supervision as part of the informal curriculum in an emergency psychiatry setting after a potentially traumatizing adverse event.

Method: The article gives a case presentation of a violent adolescent who eloped from his hospital Emergency Department and provides a description of team supervision sessions that facilitated informal learning for residents and medical students after this event.

Results: Reflective team supervision sessions after this event resulted both in improved resident well-being and learning opportunities, as well as hospital quality improvement designed to prevent future elopements.

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