It has been suggested that this article or section be merged with functional neuroimaging. (Discuss)

It has been suggested that this article or section be merged with brain mapping. (Discuss)

Neuroimaging includes the use of various techniques to either directly or indirectly image the structure, function/pharmacology of the brain. It is a relatively new discipline within medicine and neuroscience. Wikipedia does not have an article with this exact name. ... Functional neuroimaging is the use of neuroimaging technology to measure an aspect of brain function, often with a view to understanding the relationship between activity in certain brain areas and specific mental functions. ... Wikipedia does not have an article with this exact name. ... It has been suggested that this article or section be merged into Neuroimaging. ... Imaging refers to the science of obtaining pictures or more complicated spatial representations, such as animations or 3-D computer graphics models, from physical things. ... Neuroanatomy is the anatomy of the nervous system. ... Pharmacology (in Greek: pharmakon (φάρμακον) meaning drug, and lego (λέγω) to tell (about)) is the study of how substances interact with living organisms to produce a change in function. ... In animals, the brain or encephalon (Greek for in the head), is the control center of the central nervous system, responsible for behaviour. ... Medicine is the science and art of maintaining andor restoring human health through the study, diagnosis, and treatment of patients. ... Drawing of the cells in the chicken cerebellum by S. Ramón y Cajal Neuroscience is a field that is devoted to the scientific study of the nervous system. ...

Neuroimaging falls into two broad categories: structural imaging and functional imaging. Structural imaging deals with the structure of the brain and the diagnosis of gross (large scale) intracranial disease (such as tumor), and injury. Functional imaging is used to diagnose metabolic diseases and lesions on a finer scale (such as Alzheimer's disease) and also for neurological and cognitive science research and building brain-computer interfaces. Functional imaging enables, for example, the processing of information by centers in the brain to be visualized directly. Such processing causes the involved area of the brain to increase metabolism and "light up" on the scan. Cognitive science is usually defined as the scientific study either of mind or of intelligence (e. ... // A brain-computer interface (BCI), sometimes called a direct neural interface or a brain-machine interface, is a direct communication pathway between a human or animal brain (or brain cell culture) and an external device. ...

Types of brain imaging

CAT

Main article: Computed tomography

Computed Tomography (CT) or Computed Axial Tomography (CAT) scanning uses a series of x-rays of the head taken from many different directions. Typically used for quickly viewing brain injuries, CT scanning uses a computer program that performs a numerical integral calculation (the inverse Radon transform) on the measured x-ray series to estimate how much of an x-ray beam is absorbed in a small volume of the brain. Typically the information is presented as cross sections of the brain ^[1]. In approximation, the more dense a material is, the whiter a volume of it will appear on the scan (just as in the more familiar "flat" X-rays). CT scans are primarily used for evaluating swelling from tissue damage in the brain and in assessment of ventricle size. Modern CT scanning can provide reasonably good images in a matter of minutes.
It has been suggested that Synchrotron X-ray tomographic microscopy, X-ray tomography be merged into this article or section. ... Image File history File links CTscan. ... Stroke (or cerebrovascular accident or CVA) is the clinical designation for a rapidly developing loss of brain function due to an interruption in the blood supply to all or part of the brain. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... In mathematics, the Radon transform in two dimensions is the integral transform The Radon transform integrates a function over lines in the plane, mapping a function of position to a function of the slope and the y-intercept. ...

MRI

Main article: Magnetic resonance imaging

Sagittal MRI slice at the midline.

Magnetic Resonance Imaging (MRI) uses magnetic fields and radio waves to produce high quality two- or three-dimensional images of brain structures without use of ionizing radiation (X-rays) or radioactive tracers. During an MRI, a large cylindrical magnet creates a magnetic field around the head of the patient through which radio waves are sent. When the magnetic field is imposed, each point in space has a unique radio frequency at which the signal is received and transmitted (Preuss). Sensors read the frequencies and a computer uses the information to construct an image. The detection mechanisms are so precise that changes in structures over time can be detected. Using MRI, scientists can create images of both surface and subsurface structures with a high degree of anatomical detail. MRI scans can produce cross sectional images in any direction from top to bottom, side to side, or front to back. The problem with original MRI technology was that while it provides a detailed assessment of the physical appearance, water content, and many kinds of subtle derangements of structure of the brain (such as inflammation or bleeding), it fails to provide information about the metabolism of the brain (i.e. how actively it is functioning) at the time of imaging. A distinction is therefore made between "MRI imaging" and "functional MRI imaging" (fMRI), where MRI provides only structural information on the brain while fMRI yields both structural and functional data.
“MRI” redirects here. ... Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... For other uses, see Magnet (disambiguation). ... Magnetic field lines shown by iron filings In physics, a magnetic field is a solenoidal vector field in the space surrounding moving electric charges and magnetic dipoles, such as those in electric currents and magnets. ... It has been suggested that this article or section be merged with Radio waves. ... Human heart and lungs, from an older edition of Grays Anatomy. ...

fMRI

Main article: Functional magnetic resonance imaging

Axial MRI slice at the level of the basal ganglia, showing fMRI BOLD signal changes overlayed in red (increase) and blue (decrease) tones.

Functional Magnetic Resonance Imaging (fMRI) relies on the paramagnetic properties of oxygenated and deoxygenated hemoglobin to see images of changing blood flow in the brain associated with neural activity. This allows images to be generated that reflect which brain structures are activated (and how) during performance of different tasks. Most fMRI scanners allow subjects to be presented with different visual images, sounds and touch stimuli, and to make different actions such as pressing a button or moving a joystick. Consequently, fMRI can be used to reveal brain structures and processes associated with perception, thought and action. The resolution of fMRI is about 2-3 millimeters at present, limited by the spatial spread of the hemodynamic response to neural activity. It has largely superseded PET for the study of brain activation patterns. PET, however, retains the significant advantage of being able to identify specific brain receptors (or transporters) associated with particular neurotransmitters through its ability to image radiolabelled receptor "ligands" (receptor ligands are any chemicals that stick to receptors). Functional magnetic resonance imaging (fMRI) is the use of MRI to measure the haemodynamic response related to neural activity in the brain or spinal cord of humans or other animals. ... Image File history File links FMRIscan. ... The basal ganglia (or basal nuclei) are a group of nuclei in the brain interconnected with the cerebral cortex, thalamus and brainstem. ... Structure of hemoglobin. ... In biochemistry, a receptor is a protein on the cell membrane or within the cytoplasm or cell nucleus that binds to a specific molecule (a ligand), such as a neurotransmitter, hormone, or other substance, and initiates the cellular response to the ligand. ... Neurotransmitters are chemicals that are used to relay, amplify and modulate electrical signals between a presynaptic and a postsynaptic neuron. ...

As well as research on healthy subjects, fMRI is increasingly used for the medical diagnosis of disease. Because fMRI is exquisitely sensitive to blood flow, it is extremely sensitive to early changes in the brain resulting from ischemia (abnormally low blood flow), such as the changes which follow stroke. Early diagnosis of certain types of stroke is increasingly important in neurology, since substances which dissolve blood clots may be used in the first few hours after certain types of stroke occur, but are dangerous to use afterwards. Brain changes seen on fMRI may help to make the decision to treat with these agents.
Stroke (or cerebrovascular accident or CVA) is the clinical designation for a rapidly developing loss of brain function due to an interruption in the blood supply to all or part of the brain. ...

PET

Main article: Positron emission tomography

PET scan of a normal 20-year-old brain.

Positron Emission Tomography (PET) measures emissions from radioactively labeled metabolically active chemicals that have been injected into the bloodstream. The emission data are computer-processed to produce 2- or 3-dimensional images of the distribution of the chemicals throughout the brain (Nilsson 57). The positron emitting radioisotopes used are produced by a cyclotron, and chemicals are labelled with these radioactive atoms. The labeled compound, called a radiotracer, is injected into the bloodstream and eventually makes its way to the brain. Sensors in the PET scanner detect the radioactivity as the compound accumulates in various regions of the brain. A computer uses the data gathered by the sensors to create multicolored 2- or 3-dimensional images that show where the compound acts in the brain. Especially useful are a wide array of ligands used to map different aspects of neurotransmitter activity, with by far the most commonly used PET tracer being a labeled form of glucose (see FDG). Image of a typical positron emission tomography (PET) facility Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three-dimensional image or map of functional processes in the body. ... Image File history File links PETscan. ... The first detection of the positron in 1932 by Carl D. Anderson The positron is the antiparticle or the antimatter counterpart of the electron. ... A radionuclide is an atom with an unstable nucleus. ... A pair of Dee electrodes with loops of coolant pipes on their surface at the Lawrence Hall of Science. ... In chemistry, a ligand is an atom, ion or functional group that is bonded to one or more central atoms or ions, usually metals generally through co-ordinate covalent bond. ... Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three dimensional image or map of functional processes in the body. ...

The greatest benefit of PET scanning is that different compounds can show blood flow and oxygen and glucose metabolism in the tissues of the working brain. These measurements reflect the amount of brain activity in the various regions of the brain and allow us to learn more about how the brain works. PET scans were superior to all other metabolic imaging methods in terms of resolution and speed of completion (as little as 30 seconds), when they first became available. The improved resolution permitted better study to be made as to the area of the brain activated by a particular task. The biggest drawback of PET scanning is that because the radioactivity decays rapidly, it is limited to monitoring short tasks (Nilsson 60). Before fMRI technology came online, PET scanning was the preferred method of functional (as opposed to structural) brain imaging, and it still continues to make large contributions to neuroscience.
Glucose (Glc), a monosaccharide (or simple sugar), is an important carbohydrate in biology. ... A few of the metabolic pathways in a cell. ... Drawing of the cells in the chicken cerebellum by S. Ramón y Cajal Neuroscience is a field that is devoted to the scientific study of the nervous system. ...

PET scanning is also used for diagnosis of brain disease, most notably because brain tumors, strokes, and neuron-damaging diseases which cause dementia (such as Alzheimer's disease) all cause great changes in brain metabolism, which in turn causes easily detectable changes in PET scans. PET is probably most useful in early cases of certain dementias (with classic examples being Azheimer's disease and Pick's disease) where the early damage is too diffuse and makes too little difference in brain volume and gross structure to change CT and standard MRI images enough to be able to reliably differentiate it from the "normal" range of cortical atrophy which occurs with aging (in many but not all) persons, and which does not cause clinical dementia. Picks disease has two meanings that are often confused: 1) Pathology: Neurologists currently use the term Picks disease to mean specifically one of the pathological subtypes of frontotemporal lobar degeneration (FTLD). ...

SPECT

Main article: Single photon emission computed tomography

Single Photon Emission Computed Tomography (SPECT) is similar to PET and uses gamma ray emitting radioisotopes and a gamma camera to record data that a computer uses to construct two- or three-dimensional images of active brain regions (Ball). SPECT relies on an injection of radioactive tracer, which is rapidly taken up by the brain but does not redistribute. Uptake of SPECT agent is nearly 100% complete within 30 – 60s, reflecting cerebral blood flow (CBF) at the time of injection. These properties of SPECT make it particularly well suited for epilepsy imaging, which is usually made difficult by problems with patient movement and variable seizure types. SPECT provides a "snapshot" of cerebral blood flow since scans can be acquired after seizure termination (so long as the radioactive tracer was injected at the time of the seizure). A significant limitation of SPECT is its poor resolution (about 1 cm) compared to that of MRI. Single photon emission computed tomography (SPECT) is a nuclear medicine tomographic imaging technique using gamma rays. ... This article is about electromagnetic radiation. ... A radionuclide is an atom with an unstable nucleus. ... Diagrammatic cross section of a gamma camera detector A gamma camera is an imaging device, most commonly used as a medical imaging device in nuclear medicine. ...

Like PET, SPECT also can be used to differentiate different kinds of disease process which produce dementia, and it is increasingly used for this purpose. Neuro-PET has a disadvantage of requiring use of a tracers with half-lives of at most 110 minutes, such as FDG. These must be made in a cyclotron, and are expensive or even unavailable if necessary transport times are prolonged more than a few half-lives. SPECT, however, is able to make use of tracers with much longer half-lives, such as technetium-99m, and as a result, is far more widely available. Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three dimensional image or map of functional processes in the body. ...

DOT

Main article: Diffuse optical imaging

Diffuse Optical Imaging (DOI) or Diffuse Optical Tomography (DOT) is a medical imaging modality which uses near infrared light to generate images of the body. The technique measures the optical absorption of haemoglobin, and relies on the absorption spectrum of haemoglobin varying with its oxygenation status. Diffuse optical imaging is a medical imaging modality which uses near infrared light to generate images of the body. ... Medical imaging designates the ensemble of techniques and processes used to create images of the human body (or parts thereof) for clinical purposes (medical procedures seeking to reveal, diagnose or examine disease) or medical science (including the study of normal anatomy and function). ... Image of two girls in mid-infrared (thermal) light (false-color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than that of visible light, but shorter than that of radio waves. ... Absorption, in optics, is the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make a transition between two electronic energy levels. ... 3-dimensional structure of hemoglobin Hemoglobin or haemoglobin is the iron-containing oxygen-transport metalloprotein in the red cells of the blood in mammals and other animals. ... A materials absorption spectrum shows the fraction of incident electromagnetic radiation absorbed by the material over a range of frequencies. ...

History

Main article: History of neuroimaging

In 1918 the American neurosurgeon Walter Dandy introduced the technique of ventriculography. X-ray images of the ventricular system within the brain were obtained by injection of filtered air directly into one or both lateral ventricles of the brain. Dandy also observed that air introduced into the subarachnoid space via lumbar spinal puncture could enter the cerebral ventricles and also demonstrate the cerebrospinal fluid compartments around the base of the brain and over its surface. This technique was called pneumoencephalography. The history of neuroimaging, began in the early 1900s with a technique called pneumoencephalography. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... The ventricular system is a set of structures in the brain continuous with the central canal of the spinal cord. ... Pneumoencephalography (sometimes abbreviated PEG) is a medical procedure in which cerebrospinal fluid is drained from around the brain and replaced with air, oxygen, or helium to allow the structure of the brain to show up more clearly on an X-ray picture. ...

In 1927 Egas Moniz, professor of neurology in Lisbon, introduced cerebral angiography, whereby both normal and abnormal blood vessels in and around the brain could be visualized with great accuracy. António Caetano de Abreu Freire Egas Moniz (November 29, 1874 - December 13, 1955) was a Portuguese physician and neurologist. ... Location    - Country Portugal    - Region Lisboa  - Subregion Grande Lisboa  - District or A.R. Lisbon Mayor Carmona Rodrigues  - Party PSD Area 84. ... Angiography or arteriography is a medical imaging technique in which an X-ray picture is taken to visualize the inner opening of blood filled structures, including arteries, veins and the heart chambers. ...

In the early 1970s, Allan McLeod Cormack and Godfrey Newbold Hounsfield introduced computerized axial tomography (CAT or CT scanning), and ever more detailed anatomic images of the brain became available for diagnostic and research purposes. Cormack and Hounsfield won the 1979 Nobel Prize for Physiology or Medicine for their work. Soon after the introduction of CAT in the early 1980s, the development of radioligands allowed single photon emission computed tomography (SPECT) and positron emission tomography (PET) of the brain. Allan M. Cormack at Tufts University Allan MacLeod Cormack (February 23, 1924 – May 7, 1998) was a South African-born American physicist who shared a part of the 1979 Nobel Prize in Physiology or Medicine for his work on the computerized axial tomography (CAT) scan. ... Sir Godfrey Newbold Hounsfield (28 August 1919 - 12 August 2004) was an English electrical engineer who shared the 1979 Nobel Prize for Physiology or Medicine with Allan McLeod Cormack for his part in developing the diagnostic technique of computerized axial tomography (CAT). ... CAT apparatus in a hospital Computed axial tomography (CAT), computer-assisted tomography, computed tomography, CT, or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around... List of Nobel Prize laureates in Physiology or Medicine from 1901 to the present day. ... A radioligand is a radioactive biochemical substance that is used to study the receptor systems of the brain. ... Single photon emission computed tomography (SPECT) is a nuclear medicine tomographic imaging technique using gamma rays. ... Image of a typical positron emission tomography (PET) facility Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three-dimensional image or map of functional processes in the body. ...

More or less concurrently, magnetic resonance imaging (MRI or MR scanning) was developed by researchers including Peter Mansfield and Paul Lauterbur, who were awarded the Nobel Prize for Physiology or Medicine in 2003. In the early 1980s MRI was introduced clinically, and during the 1980s a veritable explosion of technical refinements and diagnostic MR applications took place. Scientists soon learned that the large blood flow changes measured by PET could also be imaged by the correct type of MRI. Functional magnetic resonance imaging (fMRI) was born, and since the 1990s, fMRI has come to dominate the brain mapping field due to its low invasiveness, lack of radiation exposure, and relatively wide availability. As noted above fMRI is also beginning to dominate the field of stroke treatment. “MRI” redirects here. ... Sir Peter Mansfield, FRS, (born 9 October 1933), is a British physicist who was awarded the 2003 Nobel Prize in Physiology or Medicine for his discoveries concerning magnetic resonance imaging (MRI). ... Paul Christian Lauterbur, (born May 6, 1929) is an American chemist who shared the Nobel Prize in Physiology or Medicine in 2003 with Peter Mansfield for his work which made the development of magnetic resonance imaging (MRI) possible. ... List of Nobel Prize laureates in Physiology or Medicine from 1901 to the present day. ... Functional magnetic resonance imaging (fMRI) is the use of MRI to measure the haemodynamic response related to neural activity in the brain or spinal cord of humans or other animals. ...

In early 2000s the field of neuroimaging reached the stage where limited practical applications of functional brain imaging have became feasible. The main application area is crude forms of brain-computer interface. A direct mind-computer interface or direct neural interface is literally that - a direct cybernetic link between a mind and a computer. ...

See also

• Functional neuroimaging
• functional near-infrared imaging
• History of brain imaging
• Human Cognome Project
• Medical imaging
• Brain mapping
• Statistical parametric mapping
• Neuroimaging software
• Voxel-based morphometry

Functional neuroimaging is the use of neuroimaging technology to measure an aspect of brain function, often with a view to understanding the relationship between activity in certain brain areas and specific mental functions. ... This does not cite any references or sources. ... The history of brain imaging, began in the early 1900s with a technique called pneumoencephalography. ... The Human Cognome Project seeks to reverse-engineer the human brain, parallelling in many ways the Human Genome Project and its success in deciphering the human genome. ... Medical imaging designates the ensemble of techniques and processes used to create images of the human body (or parts thereof) for clinical purposes (medical procedures seeking to reveal, diagnose or examine disease) or medical science (including the study of normal anatomy and function). ... It has been suggested that this article or section be merged into Neuroimaging. ... Statistical parametric mapping or SPM is a statistical technique for examining differences in brain activity recorded during functional neuroimaging experiments using neuroimaging technologies such as fMRI or PET. It may also refer to a specific piece of software created by the Wellcome Department of Imaging Neuroscience (part of University College... Neuroimaging software is used to study the structure and function of the brain. ... Voxel based morphometry (VBM) is a neuroimaging analysis technique that allows investigation of focal differences in brain volume. ...

References

1. ^ Jeeves, p. 21

Links

• The Whole Brain Atlas @ Harvard
• The American Society of Neuroimaging (ASN).
• UCLA Neuroimaging Training Program.
• Laboratory of Neuro Imaging at UCLA

Binomial name Ucla xenogrammus Holleman, 1993 The largemouth triplefin, Ucla xenogrammus, is a fish of the family Tripterygiidae and only member of the genus Ucla, found in the Pacific Ocean from Viet Nam, the Philippines, Palau and the Caroline Islands to Papua New Guinea, Australia (including Christmas Island), and the...

Works cited

• Ball, Philip. "Brain Imaging Explained."
• Beaumont, J. Graham. Introduction to Neuropsychology. New York: The Guilford Press, 1983. 314 pages.
• Changeux, Jean-Pierre. Neuronal Man: The Biology of Mind. New York: Oxford University Press, 1985. 348 pages.
  • Jeeves, Malcom. Mind Fields: Reflections on the Science of Mind and Brain. Grand Rapids, MI: Baker Books, 1994. 141 pages.
• Johnson, Keith A. "Neuroimaging Primer." [1]
• Leventon, Michael. "Transcranial Magnetic Stimulation." In association with MIT AI Lab. [2]
• Lister, Richard G. and Herbert J. Weingartner. Perspectives on Cognitive Neuroscience. New York: Oxford University Press, 1991. 508 pages.
• Mattson, James and Merrill Simon. The Pioneers of NMR and Magnetic Resonance in Medicine. United States: Dean Books Company, 1996. 838 pages.
• Nilsson, Lars-Goran and Hans J. Markowitsch. Cognitive Neuroscience of Memory. Seattle: Hogrefe & Huber Publishers, 1999. 307 pages.
• Norman, Donald A. Perspectives on Cognitive Science. New Jersey: Ablex Publishing Corporation, 1981. 303 pages.
• Pande, G.C. "Neurosciences and Philosophy." [3]
• Rapp, Brenda. The Handbook of Cognitive Neuropsychology. Ann Arbor, MI: Psychology Press, 2001. 652 pages.
• Shorey, Jamie. "Foundations of fMRI." [4]