Neuroprosthetics: Introduction

Introduction

Neuroprosthetics is a fast-growing area that brings together Biomedical Engineering and Neuroscience and seeks to interface the neural systems directly to prostheses. The main objective is to restore motor, sensory, and cognitive functions. Neuroprosthetics are electrical stimulation technologies that replace or assist malfunctioned neuromuscular system and attempt to restore the normal body functions. These devices are either implanted or worn (like wrist band or head band) on the body. Some of the examples include intramuscular stimulation systems or implanted neuromuscular control systems (Finn & LoPresti, 2003; Hoffmann & Micera, 2011).

Neural prostheses are applied with the aim of compensating an existing motor or sensory neural dysfunction. They electrically stimulate neural information in the peripheral, spinal and central nervous system of human body to restore or replace neurological task. In this scenario, two information transfers can be distinguished. They are:

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  Inward Information Transfer: This procedure involves activating any of the intact senses by proper stimuli or by direct electrical stimulation.

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  Outward Information Transfer: This method includes stimulation after recording biological information of certain muscle of neural activation (Hoffmann & Micera, 2011; Lee, Min, Jeong, Kim, & Kim, 2011; Mahmoudi, Pohlmeyer, Prins, Geng, & Sanchez, 2013).

Neural prostheses use Electroencephalography (EEG), Electromyography (EMG) interfaces to bypass dysfunctional pathways in the nervous system, by applying electronics to replace lost function. For example, cochlear implants use electronics to detect and encode sound and then stimulate the auditory nerve to allow deaf individuals to hear. It has several applications. Some of the major ones include the following:

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  Brain machine interface for motor control.

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  Brain activity monitoring for epilepsy prediction.

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  Proprioceptive feedback for upper-limb prosthetics.

Neuroprosthetics design includes five main principles, which include:

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  In human body, motor neuron information are presented in distributed manner;

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  Multiple neuronal information can be extracted in real time;

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  Neuroprosthetics design takes the advantage of plasticity of human body;

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  Various neuronal information pattern encode the same movement; and

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  Hence, recording few neuronal information is sufficient to extract the relevant neural information (Carmena, 2013; Ganguly, Dimitrov, Wallis, & Carmena, 2011; Kramme, Hoffmann, & Pozos, 2011).

Application Of Neuroprosthetics

Neuroprosthetics has several applications. Some of the most frequently used neuroprosthetics applications are described below in brief: