Brain Computer Interface

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. In one-way BCIs, computers either accept commands from the brain or send signals to it (for example, to restore vision) but not both. Two-way BCIs would allow brains and external devices to exchange information in both directions but have yet to be successfully implanted in animals or humans.
In this definition, the word brain means the brain or nervous system of an organic life form rather than the mind. Computer means any processing or computational device, from simple circuits to silicon chips (including hypothetical future technologies such as quantum computing).
Research on BCIs began in the 1970s, but it wasn't until the mid-1990s that the first working experimental implants in humans appeared. Following years of animal experimentation, early working implants in humans now exist, designed to restore damaged hearing, sight and movement. The common thread throughout the research is the remarkable cortical plasticity of the brain, which often adapts to BCIs, treating prostheses controlled by implants as natural limbs. With recent advances in technology and knowledge, pioneering researchers could now conceivably attempt to produce BCIs that augment human functions rather than simply restoring them, previously only the realm of science fiction.

Cultured Neuronal Network

A cultured neuronal network is a cell culture comprised of brain cells which is connected to an I/O interface. Recently, the term neural networks has become associated with algorithms designed to accomplish certain tasks with great efficiency. However, research is also conducted on living neuronal networks growing on microelectrode arrays (for electrophysiological observations) or glass plates (for optical and staining methods).

Neurochip

A neurochip is a chip (integrated circuit/microprocessor) that is designed for the interaction with neuronal cells.
It is made of silicon that is doped in such a way, that it contains EOSFETs (electrolyte-oxide-semiconductor FET) that can sense the electrical activity of the neurons (action potentials) in the above-standing physiological electrolyte solution. It also contains capacitors for the electrical stimulation of these cells.

Brain

In animals, the brain is the control center of the central nervous system, responsible for behavior. In mammals, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, equilibrioception (balance), sense of taste, and olfaction (smell).
While all vertebrates have a brain, most invertebrates have either a centralized brain or collections of individual ganglia. Some animals such as cnidarians and echinoderms do not have a centralized brain, instead have a decentralized nervous system, while animals such as sponges lack both a brain and nervous system entirely.
Brains can be extremely complex. For example, the human brain contains roughly 100 billion neurons, each linked to as many as 10,000 other neurons.
The brain is the central information-processing organ of the body. It innervates the head through cranial nerves, and it communicates with the spinal cord, which innervates the body through spinal nerves. Nervous fibers transmitting signals from the brain are called efferent fibers. The fibers transmitting signals to the brain are called afferent fibers (or sensory fibers). Nerves can be afferent, efferent or mixed (i.e., containing both types of fibers).
The brain is the site of reason and intelligence, which include such components as cognition, perception, attention, memory and emotion. The brain is also responsible for control of posture and movements. It makes possible cognitive, motor and other forms of learning. The brain can perform a variety of functions automatically, without the need for conscious awareness, such as coordination of sensory systems (eg. sensory gating and multisensory integration), walking, and homeostatic body functions such as blood pressure, fluid balance, and body temperature.
The Cerebellum controls balance and movement. Without it, movements would not be coordinated.

Diagram showing the lobes of the human cerebral cortex and the cerebellum.
Many functions are controlled by coordinated activity of the brain and spinal cord. Moreover, some behaviours such as simple reflexes and basic locomotion, can be executed under spinal cord control alone.
The brain undergoes transitions from wakefulness to sleep (and subtypes of these states). These state transitions are crucially important for proper brain functioning. (For example, it is believed that sleep is important for knowledge consolidation, as the neurons appear to organize the day's stimuli during deep sleep by randomly firing off the most recently used neuron pathways; additionally, without sleep, normal subjects are observed to develop symptoms resembling mental illness, even auditory hallucinations). Every brain state is associated with characteristic brain waves.
Neurons are electrically active brain cells that process information, whereas Glial cells perform supporting function. In addition to being electrically active, neurons constantly synthesize neurotransmitters. Neurons modify their properties (guided by gene expression) under the influence of their input signals. This plasticity underlies learning and adaptation. It is notable that some unused neuron pathways (constructions which have become physically isolated from other cells) may continue to exist long after the memory is absent from consciousness, possibly developing the subconscious.

Nervous System

The nervous system is a highly specialized network whose principal components are nerves called neurons. Neurons are interconnected to each other in complex arrangements, and have the property of conducting, using electrochemical signals, a great variety of stimuli both within the nervous tissue as well as from and towards most of the other tissues. Thus, neurons coordinate multiple functions in organisms. Nervous systems are found in many multicellular animals but differ greatly in complexity between species.

Mind

Mind collectively refers to the aspects of intellect and consciousness manifested as combinations of thought, perception, memory, emotion, will and imagination; mind is the stream of consciousness. It includes all of the brain's conscious processes. This denotation sometimes includes, in certain contexts, the working of the human unconscious or the conscious thoughts of animals. "Mind" is often used to refer especially to the thought processes of reason.
There are many theories of the mind and its function. The earliest recorded works on the mind are by Zarathushtra, the Buddha, Plato, Aristotle, Adi Shankara and other ancient Greek, Indian and Islamic philosophers. Pre-scientific theories, based in theology, concentrated on the relationship between the mind and the soul, the supposed supernatural, divine or god-given essence of the person. Modern theories, based on scientific understanding of the brain, theorise that the mind is a phenomenon of the brain and is synonymous with consciousness.
The question of which human attributes make up the mind is also much debated. Some argue that only the "higher" intellectual functions constitute mind: particularly reason and memory. In this view the emotions - love, hate, fear, joy - are more "primitive" or subjective in nature and should be seen as different from the mind. Others argue that the rational and the emotional sides of the human person cannot be separated, that they are of the same nature and origin, and that they should all be considered as part of the individual mind.

Quantum Computer

A quantum computer is hypothetical device for computation that makes direct use of distinctively quantum mechanical phenomena, such as superposition and entanglement, to perform operations on data. In a classical (or conventional) computer, information is stored as bits; in a quantum computer, it is stored as qubits (quantum bits). The basic principle of quantum computation is that the quantum properties can be used to represent and structure data, and that quantum mechanisms can be devised and built to perform operations with this data.
Although quantum computing is still in its infancy, experiments have been carried out in which quantum computational operations were executed on a very small number of qubits. Research in both theoretical and practical areas continues at a frantic pace, and many national government and military funding agencies support quantum computing research to develop quantum computers for both civilian and national security purposes, such as cryptanalysis. If large-scale quantum computers can be built, they will be able to solve certain problems much faster than any of our current classical computers (for example Shor's algorithm). Quantum computers are different from other computers such as DNA computers and traditional computers based on transistors. Some computing architectures such as optical computers may use classical superposition of electromagnetic waves, but without some specifically quantum mechanical resources such as entanglement, they haven't computational speed-up as quantum computers.

Cortical Plasticity

Neuroplasticity (variously referred to as brain plasticity or cortical plasticity or cortical re-mapping) refers to the changes that occur in the organization of the brain as a result of experience. A surprising consequence of neuroplasticity is that the brain activity associated with a given function can move to a different location as a consequence of normal experience or brain damage/recovery.
The concept of neuroplasticity pushes the boundaries of the brain areas that are still re-wiring in response to changes in environment. Several decades ago, the consensus was that lower brain and neocortical areas were immutable after development, whereas areas related to memory formation, such as the hippocampus and dentate gyrus, where new neurons continue to be produced into adulthood, were highly plastic.Hubel and Wiesel had demonstrated that ocular dominance columns in the lowest neocortical visual area, V1, were largely immutable after the critical period in development. Critical periods also were studied for language and suggested it was likely that the sensory pathways were fixed after their respective critical periods. Environmental changes could cause changes in behavior and cognition by modifying the connections of the new neurons in the hippocampus.

BCI vs Neuroprosthetics

Neuroprosthetics is an area of neuroscience concerned with neural prostheses — using artificial devices to replace the function of impaired nervous systems or sensory organs. The most widely used neuroprosthetic device is the cochlear implant, which was implanted in approximately 100,000 people worldwide as of 2006. There are also several neuroprosthetic devices that aim to restore vision, including retinal implants, although this article only discusses implants directly into the brain.
The differences between BCIs and neuroprosthetics are mostly in the ways the terms are used: neuroprosthetics typically connect the nervous system, to a device, whereas the term "BCIs" usually connect the brain (or nervous system) with a computer system. Practical neuroprosthetics can be linked to any part of the nervous system, for example peripheral nerves, while the term "BCI" usually designates a narrower class of systems which interface with the central nervous system.
The terms are sometimes used interchangeably and for good reason. Neuroprosthetics and BCI seek to achieve the same aims, such as restoring sight, hearing, movement, ability to communicate, and even cognitive function. Both use similar experimental methods and surgical techniques.

Animal BCI's research

Several laboratories have managed to record signals from monkey and rat cerebral cortexes in order to operate BCIs to carry out movement. Monkeys have navigated computer cursors on screen and commanded robotic arms to perform simple tasks simply by thinking about the task and without any motor output. Other research on cats has decoded visual signals.

Early work
Studies that developed algorithms to reconstruct movements from motor cortex neurons, which control movement, date back to the 1970s. Work by groups led by Schmidt, Fetz and Baker in the 1970s established that monkeys could quickly learn to voluntarily control the firing rate of individual neurons in the primary motor cortex via closed-loop operant conditioning, a training method using punishment and rewards.
In the 1980s, Apostolos Georgopoulos at Johns Hopkins University found a mathematical relationship between the electrical responses of single motor-cortex neurons in rhesus macaque monkeys and the direction that monkeys moved their arms (based on a cosine function). He also found that dispersed groups of neurons in different areas of the brain collectively controlled motor commands but was only able to record the firings of neurons in one area at a time because of technical limitations imposed by his equipment.
There has been rapid development in BCIs since the mid-1990s.Several groups have been able to capture complex brain motor centre signals using recordings from neural ensembles (groups of neurons) and use these to control external devices, including research groups led by Richard Andersen, John Donoghue, Phillip Kennedy, Miguel Nicolelis, and Andrew Schwartz.

Invasive BCI

Invasive BCI research has targeted repairing damaged sight and providing new functionality to paralysed people. Invasive BCIs are implanted directly into the grey matter of the brain during neurosurgery. As they rest in the grey matter, invasive devices produce the highest quality signals of BCI devices but are prone to scar-tissue build-up, causing the signal to become weaker or even lost as the body reacts to a foreign object in the brain.

Jens Naumann, a man with acquired blindness, being interviewed about his vision BCI on CBS's The Early Show
In vision science, direct brain implants have been used to treat non-congenital (acquired) blindness. One of the first scientists to come up with a working brain interface to restore sight was private researcher William Dobelle.
Dobelle's first prototype was implanted into "Jerry," a man blinded in adulthood, in 1978. A single-array BCI containing 68 electrodes was implanted onto Jerry’s visual cortex and succeeded in producing phosphenes, the sensation of seeing light. The system included cameras mounted on glasses to send signals to the implant. Initially, the implant allowed Jerry to see shades of grey in a limited field of vision at a low frame-rate. This also required him to be hooked up to a two-ton mainframe, but shrinking electronics and faster computers made his artificial eye more portable and now enable him to perform simple tasks unassisted.

Partially-invasive BCI's

Partially invasive BCI devices are implanted inside the skull but rest outside the brain rather than amidst the grey matter. They produce better resolution signals than non-invasive BCIs where the bone tissue of the cranium deflects and deforms signals and have a lower risk of forming scar-tissue in the brain than fully-invasive BCIs.
Electrocorticography (ECoG) measures the electrical activity of the brain taken from beneath the skull in a similar way to non-invasive electroencephalography (see below), but the electrodes are embedded in a thin plastic pad that is placed above the cortex, beneath the dura mater. ECoG technologies were first trialed in humans in 2004 by Eric Leuthardt and Daniel Moran from Washington University in St Louis. In a later trial, the researchers enabled a teenage boy to play Space Invaders using his ECoG implant. This research indicates that it is difficult to produce kinematic BCI devices with more than one dimension of control using ECoG.
Light Reactive Imaging BCI devices are still in the realm of theory. These would involve implanting a laser inside the skull. The laser would be trained on a single neuron and the neuron's reflectance measured by a separate sensor. When the neuron fires, the laser light pattern and wavelengths it reflects would change slightly. This would allow researchers to monitor single neurons but require less contact with tissue and reduce the risk of scar-tissue build-up.
This signal can be either subdural or epidural, but it is not signal taken from within the brain parenchyma itself. It has not been studied extensively until recently due to the limited access of subjects. Currently, the only manner to acquire the signal for study is through the use of patients requiring invasive monitoring for localization and resection of an epileptogenic focus.

Non-ivasive BCI's

As well as invasive experiments, there have also been experiments in humans using non-invasive neuroimaging technologies as interfaces. Signals recorded in this way have been used to power muscle implants and restore partial movement in an experimental volunteer. Although they are easy to wear, non-invasive implants produce poor signal resolution because the skull dampens signals, dispersing and blurring the electromagnetic waves created by the neurons. Although the waves can still be detected it is more difficult to determine the area of the brain that created them or the actions of individual neurons.
Electroencephalography (EEG) is the most studied potential non-invasive interface, mainly due to its fine temporal resolution, ease of use, portability and low set-up cost. But as well as the technology's susceptibility to noise, another substantial barrier to using EEG as a brain-computer interface is the extensive training required before users can work the technology. For example, in experiments beginning in the mid-1990s, Niels Birbaumer of the University of Tübingen in Germany used EEG recordings of slow cortical potential to give paralysed patients limited control over a computer cursor. (Birbaumer had earlier trained epileptics to prevent impending fits by controlling this low voltage wave.) The experiment saw ten patients trained to move a computer cursor by controlling their brainwaves. The process was slow, requiring more than an hour for patients to write 100 characters with the cursor, while training often took many months.

Cell-culture BCI's

Researchers have built devices to interface with neural cells and entire neural networks in cultures outside animals. As well as furthering research on animal implantable devices, experiments on cultured neural tissue have focused on building problem-solving networks, constructing basic computers and manipulating robotic devices. Research into techniques for stimulating and recording from individual neurons grown on semiconductor chips is sometimes referred to as neuroelectronics or neurochips.

World first: Neurochip developed by Caltech researchers Jerome Pine and Michael Maher
Development of the first working neurochip was claimed by a Caltech team led by Jerome Pine and Michael Maher in 1997. The Caltech chip had room for 16 neurons.
In 2003, a team led by Theodore Berger at the University of Southern California started work on a neurochip designed to function as an artificial or prosthetic hippocampus. The neurochip was designed to function in rat brains and is intended as a prototype for the eventual development of higher-brain prosthesis. The hippocampus was chosen because it is thought to be the most ordered and structured part of the brain and is the most studied area. Its function is to encode experiences for storage as long-term memories elsewhere in the brain.
Thomas DeMarse at the University of Florida used a culture of 25,000 neurons taken from a rat's brain to fly a F-22 fighter jet aircraft simulator. After collection, the cortical neurons were cultured in a petri dish and rapidly began to reconnect themselves to form a living neural network. The cells were arranged over a grid of 60 electrodes and used to control the pitch and yaw functions of the simulator. The study's focus was on understanding how the human brain performs and learns computational tasks at a cellular level.

Biomechatronics

Biomechatronics is an applied interdisciplinary science that aims to integrate mechanical elements in the human body, both for therapeutic uses (e.g. artificial hearts) and for the augmentation of existing abilities. Primary applications include technologies developed for the military. Biomechatronics comprises aspects of biology, mechanics, and electronics.

Bionics

Bionics (also known as biomimetics, biognosis, biomimicry, or bionical creativity engineering) is the application of biological methods and systems found in nature to the study and design of engineering systems and modern technology. The word "bionic" was coined by Jack E. Steele in 1958, possibly originating from the Greek word "βίον", pronounced "bion", meaning "unit of life" and the suffix -ic, meaning "like" or "in the manner of", hence "like life". Some dictionaries, however, explain the word as being formed from "biology" + "electronics".
The transfer of technology between lifeforms and synthetic constructs is, according to proponents of bionic technology, desirable because evolutionary pressure typically forces living organisms, including fauna and flora, to become highly optimized and efficient. A classical example is the development of dirt- and water-repellent paint (coating) from the observation that the surface of the lotus flower plant is practically unsticky for anything (the lotus effect).
Examples of bionics in engineering include the hulls of boats imitating the thick skin of dolphins; sonar, radar, and medical ultrasound imaging imitating the echolocation of bats.
In the field of computer science, the study of bionics has produced artificial neurons, artificial neural networks, and swarm intelligence. Evolutionary computation was also motivated by bionics ideas but it took the idea further by simulating evolution in silico and producing well-optimized solutions that had never appeared in nature.
It is estimated by Julian Vincent, professor of biomimetics at the University of Bath in the UK, that "at present there is only a 10% overlap between biology and technology in terms of the mechanisms used".

Biomedical Engineering (BME)

Biomedical engineering (BME) — sometimes referred to as Bioengineering — is the application of engineering principles and techniques to the medical field. It combines the design and problem solving skills of engineering with the medical and biological science to help improve patient health care and the quality of life of healthy individuals.
As a relatively new discipline, much of the work in biomedical engineering consists of research and development, covering an array of fields: bioinformatics, medical imaging, image processing, physiological signal processing, biomechanics, biomaterials and bioengineering, systems analysis, 3-D modeling, etc. Examples of concrete applications of biomedical engineering are the development and manufacture of biocompatible prostheses, medical devices, diagnostic devices and imaging equipment such as MRIs and EEGs, and pharmaceutical drugs.

Medical Device

A medical device is an object which is useful for diagnostic or therapeutic purposes. Examples of medical devices include medical thermometers, blood sugar meters, and X-ray machines.
A medical device is an instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent, or other similar or related article, including a component part, or accessory which is:
recognized in the official National Formulary, or the United States Pharmacopoeia, or any supplement to them,
intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease, in man or other animals, or
intended to affect the structure or any function of the body of man or other animals, and which does not achieve any of its primary intended purposes through chemical action within or on the body of man or other animals and which is not dependent upon being metabolized for the achievement of any of its primary intended purposes.

Medical Thermometers

Medical thermometers are used for measuring human body temperature, with the tip of the thermometer being inserted either into the mouth (oral temperature), under the armpit (axillary temperature), or into the rectum via the anus (rectal temperature).

Blood Sugar Monitoring

Blood glucose monitoring is a way of testing how much glucose is in the blood (glycemia).
This is important in the care of diabetes mellitus. Most people with Type 2 diabetes need to test at least once per day (usually before breakfast) to assess the effectiveness of their diet and exercise for controlling their blood glucose levels.[citation needed] Many people with Type 2 are using an oral medication to combat their insulin resistance, and must test their blood glucose before and after breakfast to assess the effectiveness of their dosage. All people who need to inject insulin, both for Type 1 diabetes and Type 2, need also to test their blood sugar more often (3 to 10 times per day) to assess the effectiveness of their prior insulin dose and to calculate their next insulin dose.
Improved technology for measuring blood glucose is rapidly changing the standards of care for all diabetic people. There are several methods of blood glucose testing currently available.

X-ray Machine

An X-ray machine utilizes electromagnetic radiation to produce an image of an object, usually for the purpose of visualizing something located below the object's surface. The machine is made up of an X-ray source or X-ray tube, an x-ray detection system, and positioning hardware to align two balls with the object to be imaged.

Medical Equipments

Medical equipment is designed to aid in the diagnosis, monitoring or treatment of medical conditions. These devices are usually designed with rigorous safety standards.
See also the main articles: implant, artificial limbs, corrective lenses, cochlear implants, dental implants, prosthetics (ocular, facial)
There are several basic types:
Diagnostic equipment includes medical imaging machines, used to aid in diagnosis. Examples are ultrasound and MRI machines, PET and CT scanners, and x-ray machines.
Therapeutic equipment includes infusion pumps, medical lasers and LASIK surgical machines.
Life support equipment is used maintain a patient's bodily function. These include medical ventilators, heart-lung machines, ECMO, and dialysis machines.
Medical monitors allow medical staff to measure a patient's medical state. Monitors may measure patient vital signs and other parameters including ECG, EEG, blood pressure, and dissolved gases in the blood.
Medical laboratory equipment automates or help analyze blood, urine and genes.
Diagnostic Medical Equipment may also be used in the home for certain purposes, e.g. for the control of diabetes mellitus
A Biomedical equipment technician or BMET is a vital component of the healthcare delivery system. Employed primarily by hospitals, BMETs are the people responsible for maintaining a facility's medical equipment.

Mechatronics

Mechatronics is the combination of mechanical engineering, electronic engineering and software engineering. The purpose of this interdisciplinary engineering field is the study of automata from an engineering perspective and serves the purposes of controlling advanced hybrid systems. The word itself is a portmanteau of 'Mechanics' and 'Electronics'.

Description
Aerial Venn diagram from RPI's website describes the various fields that make up Mechatronics
Mechatronics is centred on mechanics, electronics, control engineering, computing, molecular engineering (from nanochemistry and biology) which, combined, make possible the generation of simpler, more economical, reliable and versatile systems. The portmanteau "Mechatronics" was first coined by Mr. Tetsuro Mori, a senior engineer of the Japanese company Yaskawa, in 1969. Mechatronics may alternatively be referred to as "electromechanical systems" or less often as "control and automation engineering".
Engineering cybernetics deals with the question of control engineering of mechatronic systems. It is used to control or regulate such a system (see control theory). Through collaboration the mechatronic modules perform the production goals and inherit flexible and agile manufacturing properties in the production scheme. Modern production equipment consists of mechatronic modules that are integrated according to a control architecture. The most known architectures involve hierarchy, polyarchy, hetaerachy (often misspelled as heterarchy) and hybrid. The methods for achieving a technical effect are described by control algorithms, which may or may not utilize formal methods in their design. Hybrid-systems important to Mechatronics include production systems, synergy drives, planetary exploration rovers, automotive subsystems such as anti-lock braking systems, spin-assist and every day equipment such as autofocus cameras, video, hard disks, CD-players, washing machines.

Neural Engineering

Neural engineering is a discipline that uses engineering techniques to understand, repair, replace, enhance, or exploit the properties of neural systems. Neural engineers are uniquely qualified to solve design problems at the interface of living neural tissue and non-living constructs.

This branch of bioengineering draws on the fields of computational neuroscience, experimental neuroscience, clinical neurology, electrical engineering and signal processing of living neural tissue, and encompasses elements from robotics, cybernetics, computer engineering, neural tissue engineering, materials science, and nanotechnology.
Prominent goals in the field include restoration and augmentation of human function via direct interactions between the nervous system and artificial devices.
Much current research is focused on understanding the coding and processing of information in the sensory and motor systems, quantifying how this processing is altered in the pathological state, and how it can be manipulated through interactions with artificial devices including brain-computer interfaces and neuroprosthetics.

Cybernetics

Cybernetics is the interdisciplinary study of the structure of complex systems, especially communication processes, control mechanisms and feedback principles. Cybernetics is closely related to control theory and systems theory.
Contemporary cybernetics began as an interdisciplinary study connecting the fields of control systems, electrical network theory, mechanical engineering, logic modeling, evolutionary biology and neuroscience in the 1940s. Other fields of study which have influenced or been influenced by cybernetics include game theory, system theory (a mathematical counterpart to cybernetics), psychology (especially neuropsychology, behavioral psychology, cognitive psychology), philosophy, and architecture.

Isolated Brain

Isolated brain refers to keeping a brain alive in-vitro. This is done either by perfusion by a blood substitute, often an oxygenated solution of various salts, or by submerging the brain in oxygenated artificial cerebrospinal fluid(Bohlen, Halbach). It is the biological counterpart of brain in a vat. A related concept, attaching the brain or head to the circulatory system of another organism, is called a head transplant. An isolated brain however is more typically attached to an artificial perfusion device rather than a biological body.
The brains of many different organisms have been kept alive in-vitro for hours, or in some cases days. The central nervous system of invertebrate animals is often easily maintained as they need less oxygen and to a larger extent get their oxygen from CSF, for this reason the brains are more easily maintained without perfusion (Luksch, Walkowiak). Mammalian brains on the other hand have a much lesser degree of survival without perfusion and an artificial blood perfusate is usually used.
Most research on isolating mammalian brains has been done on guinea pigs.

Blood Substitutes

Blood substitutes, often called artificial blood, are used to fill fluid volume and/or carry oxygen and other blood gases in the cardiovascular system. Although commonly used, the term is not accurate since human blood performs many important functions. Red blood cells transport oxygen, white blood cells defend against disease, platelets promote clotting, and plasma proteins perform various functions. The preferred and more accurate terms are volume expanders for inert products, and oxygen therapeutics for oxygen-carrying products. Examples of these two "blood substitute" categories:
Volume expanders: inert and merely increase blood volume. These may be crystalloid-based (Ringer's lactate, normal saline, D5W (dextrose 5% in water) or colloid-based (Haemaccel, Gelofusin).
Oxygen therapeutics: mimic human blood's oxygen transport ability. Examples: Perftec, Hemopure, Oxygent, PolyHeme and Perftoran.
Oxygen therapeutics are in turn broken into two categories based on transport mechanism: perfluorocarbon based, and hemoglobin based.
Volume expanders are widely available and are used in both hospitals and first response situations by paramedics and emergency medical technicians. Oxygen therapeutics are in clinical trials in the U.S. and Europe, however Hemopure is more widely available in South Africa.

Cerebrospinal Fluid

Cerebrospinal fluid (CSF), Liquor cerebrospinalis, is a clear bodily fluid that occupies the subarachnoid space and the ventricular system around and inside the brain. Essentially, the brain "floats" in it.
More specifically the CSF occupies the space between the arachnoid mater (the middle layer of the brain cover, meninges) and the pia mater (the layer of the meninges closest to the brain). Moreover it constitutes the content of all intra-cerebral (inside the brain, cerebrum) ventricles, cisterns and sulci (singular sulcus), as well as the central canal of the spinal cord.
It is an approximately isotonic solution and acts as a "cushion" or buffer for the cortex, providing also a basic mechanical and immunological protection to the brain inside the skull.

Head Transplant

A head transplant is a surgical operation involving the replacement of an organism's head with a replacement head. It should not be confused with another hypothetical surgical operation, the brain transplant. Head transplantation inevitably involves decapitating the patient.
Since the technology required to reattach a severed spinal cord has not yet been developed, the subject of a head transplant would be a quadriplegic, unless proper therapies, presumably along the lines of stem cell therapy, had been developed. This technique has been proposed as possibly useful for people who are already quadriplegics, and who are suffering from widespread organ failures which would otherwise require many different and difficult transplant surgeries. It may also be useful for people who would rather be quadriplegic than dead (for example because of progress in brain-computer interfaces). As of this time, there is no uniform consensus on the ethics of such a procedure.

Cyberware

Cyberware is a relatively new and unknown field (a proto-science, or more adequately a “proto-technology”). In science fiction circles, however, it is commonly known to mean the hardware or machine parts implanted in the human body and acting as an interface between the central nervous system and the computers or machinery connected to it. More formally:
Cyberware is technology that attempts to create a working interface between machines/computers and the human nervous system, including (but not limited to) the brain.
Examples of potential cyberware cover a wide range, but current research tends to approach the field from one of two different angles: Interfaces or Prosthetics.

Interfaces(headwear)

The first variety attempts to connect directly with the brain. The data-jack is probably the best-known, having heavily featured in works of fiction (even in mainstream productions such as Johnny Mnemonic, the cartoon Exosquad, and The Matrix). Unfortunately, it is currently the most difficult object to implement, but it is also the most important in terms of interfacing directly with the mind. In science fiction the data-jack is the envisioned I/O port for the brain. Its job is to translate thoughts into something meaningful to a computer, and to translate something from a computer into meaningful thoughts for humans. Once perfected, it would allow direct communication between computers and the human mind.
Large university laboratories conduct most of the experiments done in the area of direct neural interfaces. For ethical reasons, the tests are usually performed on animals or slices of brain tissue from donor brains. The mainstream research currently focuses on electrical impulse monitoring, recording and translating the many different electrical signals that the brain transmits. A number of companies are working on what is essentially a "hands-free" mouse or keyboard. This technology uses these brain signals to control computer functions. These interfaces are sometimes called Brain-Machine Interfaces (BMI).
The more intense research, concerning full in-brain interfaces, is being studied, but is in its infancy. Few can afford the huge cost of such enterprises, and those who can, find the work slow-going and very far from the ultimate goals. Current research has reached the level where limited control over a computer is possible using thought commands alone. Most recently, after being implanted with a Massachusetts-based firm Cyberkinetics chip called BrainGate™, a quadriplegic man was able to compose and check email.

Prosthetics (bodyware)

The second variety of cyberware consists of a more modern form of the rather old field of prosthetics. Modern prostheses attempt to deliver a natural functionality and appearance. In the sub-field where prosthetics and cyberware cross over, experiments have been done where microprocessors, capable of controlling the movements of an artificial limb, are attached to the severed nerve-endings of the patient. The patient is then taught how to operate the prosthetic, trying to learn how to move it as though it were a natural limb.
Crossing over between prostheses and interfaces are those pieces of equipment attempting to replace lost senses. A great success in this field is the cochlear implant. A tiny device inserted into the inner ear, it replaces the lost functionality of damaged, or merely missing, hair cells (the cells that, when stimulated, create the sensation of sound). This device comes firmly under the field of prosthetics, but experiments are also being performed to tap into the brain itself. Coupled with a speech-processor, this could be a direct link to the speech centres of the brain.

Mind control

Mind control (or "brainwashing") refers to a broad range of psychological tactics able to subvert an individual's control of his own thinking, behavior, emotions, or decisions. The concept is closely related to hypnosis, but differs in practical approach.
There are a number of controversial issues regarding mind control and the methods by which control might be attained (either direct or more subtle) are the focus of study among psychologists, neuroscientists, and sociologists.
The question of mind control has been discussed in relation to religion, politics, prisoners of war, totalitarianism, black operations, neural cell manipulation, cults, terrorism, torture, parental alienation, and even battered person syndrome.
Mind control as a defense tactic (see also temporary insanity) was rejected by the court in the case of Patty Hearst, and in several court cases involving New Religious Movements.

Neuroprosthetics

Neuroprosthetics (also called Neural Prosthetics) is a discipline related to neuroscience and biomedical engineering concerned with developing neural prostheses, artificial devices to replace or improve the function of an impaired nervous system. The neuroprosthetic seeing the most widespread use is the cochlear implant, with approximately 100,000 in use worldwide as of 2006.

The first cochlear implant dates back to 1957. Other landmarks include the first motor prosthesis for foot drop in hemiplegia in 1961, the first auditory brainstem implant in 1977 and a peripheral nerve bridge implanted into spinal cord of adult rat in 1981. Paraplegics were helped in standing with a lumbar anterior root implant (1988) and in walking with Functional Electrical Stimulation (FES).
Regarding the development of electrodes implanted in the brain, an early difficulty was reliably locating the electrodes, originally done by inserting the electrodes with needles and breaking off the needles at the desired depth. Recent systems utilize more advanced probes, such as those used in deep brain stimulation to alleviate the symptoms of Parkinson's Disease. The problem with either approach is that the brain floats free in the skull while the probe does not, and relatively minor impacts, such as a low speed car accident, are potentially damaging. Some researchers, such as Kensall Wise at the University of Michigan, have proposed tethering 'electrodes to be mounted on the exterior surface of the brain' to the inner surface of the skull. However, even if successful, tethering would not resolve the problem in devices meant to be inserted deep into the brain, such as in the case of deep brain stimulation (DBS).

Brain pacemakers

Brain pacemakers" are used to treat people who suffer from epilepsy, Parkinson's disease, clinical depression and other diseases. The pacemaker is a medical device that is implanted into the brain to send electrical signals into the tissue. Depending on the area of the brain that is targeted, the treatment is called deep brain stimulation, or cortical stimulation. Brain stimulation may be used both in treatment and prevention. Pacemakers may also be implanted outside the brain, on or near the spinal cord (spinal cord stimulation), and around cranial nerves such as the vagus nerve (vagus nerve stimulation), and on or near peripheral nerves.

Dystonia

Dystonia is a neurological movement disorder in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The disorder may be inherited or caused by other factors such as birth-related or other physical trauma, infection, poisoning or reaction to drugs.
Causes
The cause(s) of dystonia are not yet known or understood; however, they are categorized as follows on a theoretical basis:
Primary dystonia is suspected to be caused by a pathology of the central nervous system, likely originating in those parts of the brain concerned with motor function, such as the basal ganglia, and the GABA (gamma-aminobutyric acid) producing Purkinje neurons. The precise cause of primary dystonia is unknown. In many cases it may involve some genetic predisposition towards the disorder combined with environmental conditions.
Secondary dystonia refers to dystonia brought on by some identified cause, usually involving brain damage, or by some unidentified cause such as chemical imbalance. Some cases of (particularly focal) dystonia are brought on after trauma, are induced by certain drugs (tardive dystonia), or may be the result of diseases of the nervous system such as Wilson's disease.

Symptoms
Symptoms vary according to the kind of dystonia involved. In most cases, dystonia tends to lead to abnormal posturing, particularly on movement. Many sufferers have continuous pain, cramping and relentless muscle spasms due to involuntary muscle movements.
Early symptoms may include loss of precision muscle coordination (sometimes first manifested in declining penmanship, frequent small injuries to the hands, dropped items and a noticeable increase in dropped or chipped dishes), cramping pain with sustained use and trembling. Significant muscle pain and cramping may result from very minor exertions like holding a book and turning pages. It may become difficult to find a comfortable position for arms and legs with even the minor exertions associated with holding arms crossed causing significant pain similar to restless leg syndrome. Affected persons may notice trembling in the diaphragm while breathing, or the need to place hands in pockets, under legs while sitting or under pillows while sleeping to keep them still and to reduce pain. Trembling in the jaw may be felt and heard while lying down, and the constant movement to avoid pain may result in TMJ-like symptoms and the grinding and wearing down of teeth. The voice may crack frequently or become harsh, triggering frequent throat clearing. Swallowing can become difficult and accompanied by painful cramping.

Chronic Pain

Chronic pain was originally defined as pain that has lasted 6 months or longer. More recently it has been defined as pain that persists longer than the temporal course of natural healing, associated with a particular type of injury or disease process.
The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage." It is important to note that pain is subjective in nature and is defined by the person experiencing it, and the medical community's understanding of chronic pain now includes the impact that the mind has in processing and interpreting pain signals.

Parkinson's Desease

Parkinson's disease (also known as Parkinson disease or PD) is a degenerative disorder of the central nervous system that often impairs the sufferer's motor skills and speech.
Parkinson's disease belongs to a group of conditions called movement disorders. It is characterized by muscle rigidity, tremor, a slowing of physical movement (bradykinesia) and, in extreme cases, a loss of physical movement (akinesia). The primary symptoms are the results of decreased stimulation of the motor cortex by the basal ganglia, normally caused by the insufficient formation and action of dopamine, which is produced in the dopaminergic neurons of the brain. Secondary symptoms may include high level cognitive dysfunction and subtle language problems. PD is both chronic and progressive.
PD is the most common cause of chronic progressive parkinsonism, a term which refers to the syndrome of tremor, rigidity, bradykinesia and postural instability. PD is also called "primary parkinsonism" or "idiopathic PD" (classically meaning having no known cause although this term is not strictly true in light of the plethora of newly discovered genetic mutations). While many forms of parkinsonism are "idiopathic", "secondary" cases may result from toxicity most notably drugs, head trauma, or other medical disorders.

Clinical Depression

Clinical depression (also called major-depressive disorder or unipolar depression) is a psychiatric disorder, characterized by a pervasive low mood, loss of interest in usual activities and diminished ability to experience pleasure.
Although the term "depression" is commonly used to describe a temporary depressed mood when one "feels blue", clinical depression is a serious and often disabling condition that can significantly affect a person's work, family and school life, sleeping and eating habits, general health and ability to enjoy life. The course of clinical depression varies widely: depression can be a once in a life-time event or have multiple recurrences, it can appear either gradually or suddenly, and either last for a few months or be a life-long disorder. Having depression is a major risk factor for suicide; in addition, people with depression suffer from higher mortality from other causes.
Clinical depression may be isolated or be a secondary result of a primary condition such as bipolar disorder or chronic pain. When specific treatment is indicated, this is usually psychotherapy and antidepressants.

Deep Brain Stimulation

In neurotechnology, deep brain stimulation (DBS) is a surgical treatment involving the implantation of a medical device called a brain pacemaker, which sends electrical impulses to specific parts of the brain. DBS in select brain regions has provided remarkable therapeutic benefits for otherwise treatment-resistant movement and affective disorders such as chronic pain, Parkinson’s disease, tremor and dystonia. Yet, despite the long history of DBS, its underlying principles and mechanisms are still not clear. DBS directly changes brain activity in a controlled manner, its effects are reversible (unlike those of lesioning techniques) and is one of only a few neurosurgical methods that allows blinded studies.
The Food and Drug Administration (FDA) approved DBS as a treatment for essential tremor in 1997, for Parkinson's disease in 2002, and dystonia in 2003. DBS is also routinely used to treat chronic pain and has been used to treat various affective disorders, including clinical depression. While DBS has proven helpful for some patients, there is potential for serious complications and side effects.

Neurotechnology

When the field of neuroscience began to self-organize in the 1960's, the experimental model was the laboratory rat and the technologies deployed were crude by today's standards. In a typical early example, neuroscientists would implant stimulating or recording electrodes chronically into the rat brain and attempt to use electrical stimulation (similar to modern deep brain stimulation) to change the behavior of the experimental animal. What happened in the rat brain was supposed to yield understanding of how the human brain might work.

Modern Neuroscience creates Neurotechnologies
Neuroscience has matured now to the point where, with non-invasive human brain imaging, the common experimental model is the human subject volunteer and the questions being asked, get at some of the fundamental questions of what it means to be human and to have a mind. The revolution in technologies that has made this maturation possible extends from gene to hospital bed-side and is now referred to as neurotechnology. Some examples of neurotechnology include the CAT scanner, fMRI, Positron emmision tomography, high-throughput genetic sequencing, brain proteomics and psychophamaceuticals. These technologies also include neural modeling simulations, biological computers, and human-brain interfaces (prosthetics).

Neurotechnologies present neuroethical challenges
As these new technologies have matured, ethicists have begun to raise questions of how the new technologies might be practically used and what policies might govern their use . Applications such as deception detection, neuro-marketing and the potential for artificially augmenting cognition all have policy implications.

Understanding human mind
The neurotechnology revolution has enabled the possibility for the Decade of the Mind initiative. It also offers the possibility of revealing the mechanisms by which mind and consciousness emerge from brain.

Bereitschaftspotencial

In neurology, the Bereitschaftspotential or BP (from German, "readiness potential"), also called the pre-motor potential or readiness potential (RP), is a measure of activity in the motor cortex of the brain leading up to voluntary muscle movement. The BP is a manifestation of cortical contribution to the pre-motor planning of volitional movement. It was first recorded and reported in 1964 by Hans Helmut Kornhuber and Lüder Deecke at the University of Freiburg in Germany. In 1965 the full publication appeared after many control experiments.

Brain Implants

Brain implants, often referred to as neural implants, are technological devices that connect directly to a biological subject's brain - usually placed on the surface of the brain, or attached to the brain's cortex. A common purpose of modern brain implants and the focus of much current research is establishing a biomedical prosthesis circumventing areas in the brain, which became dysfunctional after a stroke or other head injuries. This includes sensory substitution, e.g. in vision. Other brain implants are used in animal experiments simply to record brain activity for scientific reasons. Some brain implants involve creating interfaces between neural systems and computer chips, which are part of a wider research field called brain-computer interfaces. (Brain-computer interface research also includes technology such as EEG arrays that allow interface between mind and machine but do not require direct implantation of a device.)

BrainGate

BrainGate is a brain implant system developed by the bio-tech company Cyberkinetics in 2003 in conjunction with the Department of Neuroscience at Brown University. The device was designed to help those who have lost control of their limbs, or other bodily functions, such as patients with amyotrophic lateral sclerosis (ALS) or spinal cord injury. The computer chip, which is implanted into the brain, monitors brain activity in the patient and converts the intention of the user into computer commands.
Currently the chip uses 100 hair-thin electrodes that sense the electro-magnetic signature of neurons firing in specific areas of the brain, for example, the area that controls arm movement. The activity is translated into electrically charged signals and are then sent and decoded using a program, which can move either a robotic arm or a computer cursor. According to the Cyberkinetics' website, three patients have been implanted with the BrainGate system. The company has confirmed that one patient (Matt Nagle) has a spinal cord injury, whilst another has advanced ALS.
In addition to real-time analysis of neuron patterns to relay movement, the Braingate array is also capable of recording electrical data for later analysis. A potential use of this feature would be for a neurologist to study seizure patterns in a patient with epilepsy.
Braingate is currently recruiting patients with a range of neuromuscular and neurodegenerative conditions for pilot clinical trials in the United States.

Electroencephalography (EEG)

Electroencephalography (EEG) is the measurement of electrical activity produced by the brain as recorded from electrodes placed on the scalp.
Just as the activity in a computer can be perceived on multiple different levels, from the activity of individual transistors to the function of applications, so can the electrical activity of the brain be described on relatively small to relatively large scales. At one end are action potentials in a single axon or currents within a single dendrite, and at the other end is the activity measured by the scalp EEG.
The data measured by the scalp EEG are used for clinical and research purposes. A technique similar to the EEG is intracranial EEG (icEEG), also referred to as subdural EEG (sdEEG) and electrocorticography (ECoG). These terms refer to the recording of activity from the surface of the brain (rather than the scalp). Because of the filtering characteristics of the skull and scalp, icEEG activity has a much higher spatial resolution than surface EEG.

Magnetoencephalography (MEG)

Magnetoencephalography (MEG) is an imaging technique used to measure the magnetic fields produced by electrical activity in the brain via extremely sensitive devices such as superconducting quantum interference devices (SQUIDs). These measurements are commonly used in both research and clinical settings. There are many uses for the MEG, including assisting surgeons in localizing a pathology, assisting researchers in determining the function of various parts of the brain, neurofeedback, and others.