Neurobiophysics

The nervous system is the part of an animal's body that coordinates its voluntary and involuntary actions and transmits signals to and from different parts of its body, and thereby helps to maintain the coordination between the organism and its environment. It is defined by the presence of a special type of cell : Neurons. Neurons can be distinguished from other cells in a number of ways, but their most fundamental property is that they communicate with other cells via synapses, which are membrane-to-membrane junctions containing molecular machinery that allows rapid transmission of signals, either electrical or chemical. Neural signals propagate along an axon in the form of electrochemical waves called action potentials, which produce cell-to-cell signals at points where axon terminals make synaptic contact with other cells. This action potential transmits information as all-or-none impulses of current and voltage. These are logically analogous to the bits of information transmitted in digital electronic systems.
      The coupling of electrical devices to the human nervous system has long been the realm of science fiction. However, technological advancements of the past several decades have now made this phenomenon a reality. All of these started with Hans Berger's inventing of electrical activity of the human brain and the development of electroencephalography (EEG). In 1924 Berger recorded an EEG signals from a human brain for the first time.  By analyzing EEG signals Berger was able to identify oscillatory activity in the brain. Since then numerous research had been done on this field and outstanding medical advancements have been achieved.
      Nowadays two important terms are used to describe this type of brain electronic systems. One is Neuroprosthetics and another is Brain Computer Interface (BCI).
      In general terms Neural Prosthetics are a series of devices that can substitute a motor, sensory or cognitive modality that might have been damaged as a result of an injury or a disease, whereas Brain Computer Interface (BCI) is a direct communication pathway between the brain and external devices. The major difference between BCIs and Neuroprosthetics is mostly in how the terms are used : Neuroprosthetics typically connect the nervous system to a device, whereas BCIs usually connect the brain (or nervous system) with a computer system.  However, Neuroprosthetics and BCIs seek to achieve the same aims, such as restoring sight, hearing, movement, ability to communicate, and even cognitive function.
      There are already several devices that are developed based upon these systems like, Visual Implants, Cochlear implants and Motor and cognitive neuroprothetics.
      In this seminar paper, an insight into the aspects of  BCI and Neuroprosthetics, its applications, recent developments and future prospects has been discussed.