Capsule outil : Expérience mystique et méditation : les corrélats neurobiologiques Capsule outil: Expérience mystique et méditation : les corrélats neurobiologiques Les états de grâce rapportés par les religieux ou les adeptes de la méditation sont pour le moins intrigants. Ceux qui les vivent semblent en effet avoir accès à une réalité qui échappe au commun des mortels. Or l'avènement de techniques d'enregistrement non invasives de l'activité cérébrale a ouvert la voie à une investigation scientifique à grande échelle de ces " expériences mystiques ". Et comme on va le constater, tant les athées que les croyants sont intéressés par les résultats… Il convient tout d'abord de définir ce qu'on entend par " expérience mystique " et par " méditation ". L'expérience mystique L'expérience mystique a souvent une connotation religieuse mais peut aussi référer à des sentiments " d'union avec le cosmos " expérimentés par des athées. La méditation Certains sceptiques ont avancé que la méditation ne pourrait en fait n'être rien de plus que de la somnolence.
Brain Atlas - Introduction The central nervous system (CNS) consists of the brain and the spinal cord, immersed in the cerebrospinal fluid (CSF). Weighing about 3 pounds (1.4 kilograms), the brain consists of three main structures: the cerebrum, the cerebellum and the brainstem. Cerebrum - divided into two hemispheres (left and right), each consists of four lobes (frontal, parietal, occipital and temporal). The outer layer of the brain is known as the cerebral cortex or the ‘grey matter’. – closely packed neuron cell bodies form the grey matter of the brain. Cerebellum – responsible for psychomotor function, the cerebellum co-ordinates sensory input from the inner ear and the muscles to provide accurate control of position and movement. Brainstem – found at the base of the brain, it forms the link between the cerebral cortex, white matter and the spinal cord. Other important areas in the brain include the basal ganglia, thalamus, hypothalamus, ventricles, limbic system, and the reticular activating system. Neurons
Magnetic resonance imaging Magnetic resonance imaging (MRI), nuclear magnetic resonance imaging (NMRI), or magnetic resonance tomography (MRT) is a medical imaging technique used in radiology to investigate the anatomy and function of the body in both health and disease. MRI scanners use strong magnetic fields and radiowaves to form images of the body. The technique is widely used in hospitals for medical diagnosis, staging of disease and for follow-up without exposure to ionizing radiation. Introduction Neuroimaging MRI image of white matter tracts. MRI is the investigative tool of choice for neurological cancers as it is more sensitive than CT for small tumors and offers better visualization of the posterior fossa. Cardiovascular MR angiogram in congenital heart disease Cardiac MRI is complementary to other imaging techniques, such as echocardiography, cardiac CT and nuclear medicine. Musculoskeletal Liver and gastrointestinal MRI Functional MRI Oncology How MRI works
Find out more about EEG - City University London The EEG lab Location: Department of Psychology Social Sciences Building Level 4, Room D401/402 Tel: +44 (0)20 7040 4211. EEG lab2 is located on the ground floor in room DG08A. The EEG labs are purpose-built units in the Department of Psychology. EEG enables the measuring of electrical brain activity occurring during all kinds of externally and internally triggered cognitive processes such as sensory perception, selective attention, action preparation, executive control processes, learning, working memory, etc. We employ a 64- / 32-channel EEG setup and all recordings are performed in an acoustically and electrically shielded chamber. A brief introduction to EEG research Groups of neurons firing synchronously create electrical potentials that can be measured by electrodes placed on the scalp. The image below shows EEG traces from commonly used electrodes, all placed on the scalp. Experimental procedure Data analysis EEG lab volunteers Are you interested in participating in an EEG study? Reward
Alpha wave Alpha waves are neural oscillations in the frequency range of 7.5–12.5 Hz arising from synchronous and coherent (in phase or constructive) electrical activity of thalamic pacemaker cells in humans. They are also called Berger's wave in memory of the founder of EEG. Alpha waves are one type of brain waves detected either by electroencephalography (EEG) or magnetoencephalography (MEG) and predominantly originate from the occipital lobe during wakeful relaxation with closed eyes. An alpha-like variant called mu (μ) can be found over the motor cortex (central scalp) that is reduced with movement, or the intention to move. History of alpha waves Alpha waves were discovered by German neurologist Hans Berger, most famous for his invention of the EEG. Berger took a cue from Russian physiologist Pravdich-Neminski, who used a string galvanometer to create a photograph of the electrical activity of a dog's brain. Types of alpha waves Alpha wave intrusion See also
Neurotechnology | High Resolution EEG Artistic and creative expression - Use your thoughts, feeling, and emotion to dynamically create color, music, and art. Life changing applications for disabled patients, such as controlling an electric wheelchair, mind-keyboard, or playing a hands-free game. Games & Virtual Worlds - Experience the fantasy of controlling and influencing the virtual environment with your mind. Play games developed specifically for the EPOC, or use the EmoKey to connect to current PC games and experience them in a completely new way. Market Research & Advertising - get true insight about how people respond and feel about material presented to them. Included Free with the Emotiv EPOC: EmoKey EmoKey links the Emotiv technology to your applications by easily converting detected events into any combination of keystrokes.
Diffusion MRI Diffusion MRI (or dMRI) is a magnetic resonance imaging (MRI) method which came into existence in the mid-1980s. It allows the mapping of the diffusion process of molecules, mainly water, in biological tissues, in vivo and non-invasively. Molecular diffusion in tissues is not free, but reflects interactions with many obstacles, such as macromolecules, fibers, membranes, etc. Water molecule diffusion patterns can therefore reveal microscopic details about tissue architecture, either normal or in a diseased state. The first diffusion MRI images of the normal and diseased brain were made public in 1985. Since then, diffusion MRI, also referred to as diffusion tensor imaging or DTI (see section below) has been extraordinarily successful. Its main clinical application has been in the study and treatment of neurological disorders, especially for the management of patients with acute stroke. Diffusion Given the concentration and flux where D is the diffusion coefficient. .
Positron emission tomography PET/CT-System with 16-slice CT; the ceiling mounted device is an injection pump for CT contrast agent Whole-body PET scan using 18F-FDG Positron emission tomography (PET) is a nuclear medicine, functional imaging technique that produces a three-dimensional image of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (tracer), which is introduced into the body on a biologically active molecule. Three-dimensional images of tracer concentration within the body are then constructed by computer analysis. If the biologically active molecule chosen for PET is fluorodeoxyglucose (FDG), an analogue of glucose, the concentrations of tracer imaged will indicate tissue metabolic activity by virtue of the regional glucose uptake. History The concept of emission and transmission tomography was introduced by David E. The logical extension of positron instrumentation was a design using two 2-dimensional arrays.
Invention: Microsoft mind reader - tech - 15 October 2007 - New Microsoft mind reader Not content with running your computer, Microsoft now wants to read your mind too. The company says that it is hard to properly evaluate the way people interact with computers since questioning them at the time is distracting and asking questions later may not produce reliable answers. Instead, Microsoft wants to read the data straight from the user's brain as he or she works away. So the company has come up with a method for filtering EEG data in such a way that it separates useful cognitive information from the not-so-useful non-cognitive stuff. Read the full Microsoft mind reading patent application Metamorphic amphibious vehicle The next generation of military vehicles will need to be suitable for deployment anywhere in the world within hours rather than weeks or months. Among the limiting factors for off-road travel is how far the wheels can move up and down to accommodate rough terrain. Read the full metamorphic amphibious vehicle patent application Previous
axioms Contents Contents | rgb Home | Philosophy Home | Axioms | Other Books by rgb: | The Book of Lilith | Axioms is a work that explores the true nature of human knowledge, in particular the fundamental nature of deductive and inductive reasoning. It begins by embracing Hume's Skepticism and Descartes' one ``certain'' thing, and then looking for a way out of the solipsistic hell this leaves one in in terms of ``certain'' knowledge. Indeed, to the extent that philosophy in the past has sought to provide certain answers to virtually any question at all, philosophy itself proves to be bullshit - all philosophical arguments ultimately come back to at least one unprovable premise, usually unstated, and can be refuted by simply asserting ``I don't agree with your premises.'' The way out is to give up the idea of certain knowledge. Axioms by Robert G. Dedication No book is written in a vacuum. Notice Copyright Notice Copyright Robert G. Lulu Press www.lulu.com
Video: Remote helicopter controlled by brain waves | Human World A team at the University of Minnesota, led by biomedical engineering professor Bin He, have learned to use their thoughts to steer a flying robot around a gym, making it turn, rise, dip, and even sail through a ring. Brain waves (EEG) are picked up by the electrodes of an EEG cap on the scalp. The system works thanks to the geography of the motor cortex—the area of the cerebrum that governs movement. Monitoring electrical activity from the brain, the 64 scalp electrodes of the EEG cap report the signals (or lack of signals) they detect to a computer, which translates the pattern into an electronic command. Now it’s the real deal, controlling an actual flying robot—formally, an AR [augmented reality] drone. The technology, pioneered by He, may someday allow people robbed of speech and mobility by neurodegenerative diseases to regain function by controlling artificial limbs, wheelchairs, or other devices.
Functional magnetic resonance imaging Researcher checking fMRI images Functional magnetic resonance imaging or functional MRI (fMRI) is a functional neuroimaging procedure using MRI technology that measures brain activity by detecting associated changes in blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases. The primary form of fMRI uses the Blood-oxygen-level dependent (BOLD) contrast, discovered by Seiji Ogawa. The procedure is similar to MRI but uses the change in magnetization between oxygen-rich and oxygen-poor blood as its basic measure. FMRI is used both in the research world, and to a lesser extent, in the clinical world. Overview The fMRI concept builds on the earlier MRI scanning technology and the discovery of properties of oxygen-rich blood. History Three studies in 1992 were the first to explore using the BOLD contrast in humans. Physiology
Single photon emission computed tomography Animation of a SPECT scanning procedure. Single-photon emission computed tomography (SPECT, or less commonly, SPET) is a nuclear medicine tomographic imaging technique using gamma rays. It is very similar to conventional nuclear medicine planar imaging using a gamma camera. However, it is able to provide true 3D information. This information is typically presented as cross-sectional slices through the patient, but can be freely reformatted or manipulated as required. The basic technique requires delivery of a gamma-emitting radioisotope (called radionuclide) into the patient, normally through injection into the bloodstream. Principles A Siemens brand SPECT scanner, consisting of two gamma cameras. Instead of just 'taking a picture' of anatomical structures, a SPECT scan monitors level of biological activity at each place in the 3-D region analyzed. SPECT imaging is performed by using a gamma camera to acquire multiple 2-D images (also called projections), from multiple angles.