Event-related optical signal

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Event-related optical signal
Medical diagnostics
Purposemeasure 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 set of techniques to measure and visualize aspects of the nervous system

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.

Cerebral cortex Part of a mammals brain

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

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.

Contents

Characteristics

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.

History

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.

University of Illinois at Urbana–Champaign public research university in Urbana and Champaign, Illinois, United States

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.

See also

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References

  1. Gratton, Gabriele; Chiarelli, Antonio M.; Fabiani, Monica (7 April 2017). "From brain to blood vessels and back: a noninvasive optical imaging approach". Neurophotonics. 4 (3): 031208. doi:10.1117/1.NPh.4.3.031208. PMC   5384652 . PMID   28413807.
  2. Gratton G, Fabiani M (August 2001). "Shedding light on brain function: the event-related optical signal". Trends Cogn. Sci. (Regul. Ed.). 5 (8): 357–363. doi:10.1016/S1364-6613(00)01701-0. PMID   11477005.