Event-related optical signal | |
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Medical diagnostics | |
Purpose | measure changes in optical properties of active areas of cerebral cortex |
Event-related optical signal (EROS) is a neuroimaging technique that uses infrared light through optical fibers to measure changes in optical properties of active areas of the cerebral cortex. The fast optical signal (EROS) measures changes in infrared light scattering that occur with neural activity. [1] Whereas techniques such as diffuse optical imaging (DOI) and near-infrared spectroscopy (NIRS) measure optical absorption of hemoglobin, and thus are based on cerebral blood flow, EROS takes advantage of the scattering properties of the neurons themselves, and thus provide a much more direct measure of cellular activity.
Neuroimaging or brain imaging is the use of various techniques to either directly or indirectly image the structure, function, or pharmacology of the nervous system. It is a relatively new discipline within medicine, neuroscience, and psychology. Physicians who specialize in the performance and interpretation of neuroimaging in the clinical setting are neuroradiologists.
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemispheres. The two hemispheres are joined beneath the cortex by the corpus callosum. The cerebral cortex is the largest site of neural integration in the central nervous system. It plays a key role in attention, perception, awareness, thought, memory, language, and consciousness.
Diffuse optical imaging (DOI) is a method of imaging using near-infrared spectroscopy (NIRS) or fluorescence-based methods. When used to create 3D volumetric models of the imaged material DOI is referred to as diffuse optical tomography, whereas 2D imaging methods are classified as diffuse optical topography.
EROS can pinpoint activity in the brain within millimeters and milliseconds, providing good spatial and temporal resolution at the same time. Currently, its biggest limitation is the inability to detect activity more than a few centimeters deep, which thus limits this fast optical imaging to the cerebral cortex.
EROS can be measured using photon delay or as an intensity signal. EROS can also be measured concurrently with other neuroimaging techniques, such as fMRI, fNIRS, or EEG.
EROS is a relatively new and inexpensive technique that is non-invasive to the test subject. It was developed at the University of Illinois at Urbana–Champaign in the Cognitive Neuroimaging Laboratory of Drs. Gabriele Gratton and Monica Fabiani. [2] EROS was first demonstrated in the visual cortex in 1995, and later in the motor cortex that same year.
The University of Illinois at Urbana–Champaign is a public research university in Illinois and the flagship institution of the University of Illinois system. Founded in 1867 as a land-grant institution, its campus is located in the twin cities of Champaign and Urbana.
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Cognitive neuroscience is the scientific field that is concerned with the study of the biological processes and aspects that underlie cognition, with a specific focus on the neural connections in the brain which are involved in mental processes. It addresses the questions of how cognitive activities are affected or controlled by neural circuits in the brain. Cognitive neuroscience is a branch of both neuroscience and psychology, overlapping with disciplines such as behavioral neuroscience, cognitive psychology, physiological psychology and affective neuroscience. Cognitive neuroscience relies upon theories in cognitive science coupled with evidence from neurobiology, and computational modeling.
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Arno Villringer is a director at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany; director of the Department of Cognitive Neurology at University Hospital Leipzig; and Academic Director of the Berlin School of Mind and Brain and the Mind&Brain Institute, Berlin. He holds a full professorship at University of Leipzig and an honorary professorship at Charité, Humboldt-Universität zu Berlin.
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Neal J. Cohen is a professor of psychology in the Cognitive Neuroscience division of the University of Illinois at Urbana–Champaign. He is appointed as a full-time faculty member in the Beckman Institute for Advanced Science and Technology at the University of Illinois. He is the founding director of the Center for Nutrition, Learning, and Memory (CNLM), a partnership of the University of Illinois and Abbott Laboratories as of 2011. He is also the founding director of the Interdisciplinary Health Sciences Initiative (IHSI) at the University of Illinois, formed 2014.
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