background preloader

Neurology

Facebook Twitter

Sebastian Seung: I am my connectome. Diffusion MRI image of the brain.

Image by Henning U. Voss / Nicholas D. Schiff 2008 – kaspervandenberg

VS Ramachandran on your mind. VS Ramachandran: The neurons that shaped civilization. Susan Savage-Rumbaugh on apes.

Susan Savage-Rumbaugh shows that language, complex tasks, and other intelligent behaviour. She has tought bonobo apes. This contradicts VS Ramachandran's claim in "VS Ramachandran: The neurons that shaped civilization" that humans 100.000 years ago devellopped 'mirror neurons' which led to culture. (The bonobo species probablely orginated 1.5-2.0 mln. years ago, when the Congo river separates them from their chimpansee cousins.) – kaspervandenberg

Oliver Sacks: What hallucination reveals about our minds.

Oliver Sacks talks about the Bonnet syndrome: visual hallucinations caused by randomly firing neurons. The Bonnet hallucinations are distinct from psychotic hallucinations and hallucinations caused by 'temporal lobe epilepsy'. Dr. Sacks discusses how neuron firing in specific areas, cells, or groups of cells, as observed with fMRI, cause different types of images. Dr. Sacks' presentation connects to the overview VS Ramachandran gave about low-tech clinical neurology[VS Ramachandran on your mind | TED]. Would Christopher de Charms' approach of exercising the brain while viewing it via fMRI[Christopher deCharms looks inside the brain | TED] help patients with Bonnet syndrome? – kaspervandenberg

Charles Limb: Your brain on improv.

Charles Limb studies the neurology of music and creativity. In this TED talk he shows fMRI contrast maps of his experiments with people playing memorised music versus people improvising music. He shows that the activity in the lateral prefrontal cortex, which is involved in self-monitoring, lowers. And activity in the medial prefrontal cortex goes up. Next he shows what happens when musicians improvise together. The language areas, i.e. Broca's area, became more active. The third experiment is about memorised rap versus freestyle rap: then you see activity in the visual areas and motor coordination areas, so lots of brains areas aree active in creative rapping. – kaspervandenberg

Christopher deCharms looks inside the brain. 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.[1] This technique relies on the fact that cerebral blood flow and neuronal activation are coupled.

Functional magnetic resonance imaging

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,[2] discovered by Seiji Ogawa. Diffusion MRI. Diffusion MRI (or dMRI) is a magnetic resonance imaging (MRI) method which came into existence in the mid-1980s.[1][2][3] It allows the mapping of the diffusion process of molecules, mainly water, in biological tissues, in vivo and non-invasively.

Diffusion MRI

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.[4][5] 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[edit] Tan Le: A headset that reads your brainwaves. Electroencephalography.

Simultaneous video and EEG recording of two guitarists improvising.

Electroencephalography

Electroencephalography (EEG) is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain.[1] In clinical contexts, EEG refers to the recording of the brain's spontaneous electrical activity over a short period of time, usually 20–40 minutes, as recorded from multiple electrodes placed on the scalp. Diagnostic applications generally focus on the spectral content of EEG, that is, the type of neural oscillations that can be observed in EEG signals.

EEG is most often used to diagnose epilepsy, which causes obvious abnormalities in EEG readings.[2] It is also used to diagnose sleep disorders, coma, encephalopathies, and brain death. History[edit] Henry Markram builds a brain in a supercomputer.

Henry Markram simulates a brain's neurons and the neurons' connections (ie. a 'connectome' cf. "Sebastian Seung: i am my connectome") on a supercomputer. A striking difference with AI artificial neural networks is a each neuron and its bochemistry is simulated on a processor, whereas AI uses an (over) simplified model of a few bytes as a neuron and simple caltulations (adding, multiplying) as signal exchange. Markram's technology driven approach differs from Ramachandran's low-tech (mirrors in a box) clinical approach in "Ramachandran: on your mind". – kaspervandenberg

Kwabena Boahen on a computer that works like the brain.

Kwabena Boahen argues that the miniaturisation of transistors leads to them becomming more like synapses and less like electrical components: sometimes they don't output a current when they should and sometimes they leak a current when they shouldn't. Chipdesign neeeds a paradigm shift: not accurate central processesing the bottleneck but more connections with fuzy results. Compare this to TED talks about the brain by Henry Markram and others. – kaspervandenberg

Gero Miesenboeck reengineers a brain. Jeff Hawkins on how brain science will change computing. Dan Dennett on our consciousness.

Dan Dennett argues that each person should give up his beliefs about being an expert about his/her own consiousness. He shows that the mind does tricks without you being aware how it does them. Dennett's argument supports Hawkins's case for giving up common misconceptions to form a theory of mind. – kaspervandenberg

Michael Merzenich on re-wiring the brain. Pawan Sinha on how brains learn to see. Beau Lotto: Optical illusions show how we see.

Beau Lotto uses optical illusions to demonstrate how our brain uses context to decode visual signals. – kaspervandenberg

Jeff Hawkins. Episodes - Brain Science Podcast. Neuron. All neurons are electrically excitable, maintaining voltage gradients across their membranes by means of metabolically driven ion pumps, which combine with ion channels embedded in the membrane to generate intracellular-versus-extracellular concentration differences of ions such as sodium, potassium, chloride, and calcium.

Neuron

Changes in the cross-membrane voltage can alter the function of voltage-dependent ion channels. If the voltage changes by a large enough amount, an all-or-none electrochemical pulse called an action potential is generated, which travels rapidly along the cell's axon, and activates synaptic connections with other cells when it arrives. Neurons do not undergo cell division. In most cases, neurons are generated by special types of stem cells. A type of glial cell, called astrocytes (named for being somewhat star-shaped), have also been observed to turn into neurons by virtue of the stem cell characteristic pluripotency.

Overview[edit] Neuron viewed with an electron microscope. Neuron's cobweb-like cytoskeleton (its interior scaffolding) Brain from top to bottom. The Whole Brain Atlas. Brain Atlas - Introduction. The central nervous system (CNS) consists of the brain and the spinal cord, immersed in the cerebrospinal fluid (CSF).

Brain Atlas - Introduction

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’. It covers the nuclei deep within the cerebral hemisphere e.g. the basal ganglia; the structure called the thalamus, and the ‘white matter’, which consists mostly of myelinated axons. Dick Swaab Wij zijn ons brein - UitgeverijContact. Hersenletsel achtergronden en aanpak / druk 1, H.J. Eilander. Hersenletsel heeft ingrijpende gevolgen voor de getroffenen en hun omgeving.

Hersenletsel achtergronden en aanpak / druk 1, H.J. Eilander

Iedereen die hiermee te maken heeft, als getroffene, familielid of partner of als professional, heeft behoefte aan informatie.

Neurological professions and research fields

Medical imageing. Kasper's neurology neighbours.