The Royal Academy of Engineering UK Focus for Biomedical Engineering Policy Briefing

Neural engineering Engineering is at the heart of society, underpinning and continually improving the quality of our lives. The Royal Academy of Engineering brings together the country’s most eminent engineers from all disciplines to promote excellence and support the engineering performance of the UK. Biomedical engineering creates new medical technologies and systems that can greatly improve patient care and quality of life. The UK Focus for Biomedical Engineering is the Academy’s forum for this increasingly important area of engineering in which the UK is taking a lead. Introduction interfacing technology directly with the A second example of neuroprosthetics human nervous system. is deep brain stimulation (DBS), which Biomedical engineering is constantly involves the surgical implantation of a expanding and extending the areas There are already real-world clinical medical device called a brain pacemaker of application within healthcare. solutions for areas such as controlling that sends electrical pulses to very Technological developments, coupled essential tremor through implants in with a stronger understanding of specific parts of the brain. While DBS in deep-brain stimulation for Parkinson’s biological processes brought about specific brain regions has provided very Disease, vagal nerve stimulation for help by cutting-edge research, create new good therapeutic benefits for otherwise in controlling epilepsy, and the use of areas within biomedical engineering. treatment-resistant movement and Neural engineering is one such recent cochlear implants to restore hearing in affective disorders such as chronic pain development. the profoundly deaf (neuroprosthetics). and dystonia, it is in Parkinson’s disease and tremor that DBS is best known. Neural engineering, sometimes known The technology Parkinson’s disease is a as neuroengineering, is the discipline in Neuroprosthetics is concerned with neurodegenerative disease whose which engineering skills and techniques developing neural prostheses, devices primary symptom is tremor. DBS are used to understand, repair, replace, that can substitute a motor, sensory does not cure Parkinson’s, but it can or enhance neural systems. Neural or cognitive modality that might have help manage some symptoms and engineers solve design problems at the been damaged as a result of an injury or subsequently improve the patient’s interface of living neural tissue and non- a disease. An example of such a device living systems. quality of life. At present, the procedure is is the cochlear implant. This device used only for patients whose symptoms substitutes the functions performed Like other areas in biomedical cannot be adequately controlled with by the biological components of the engineering, neural engineering medications, or in whom medications ear and the cochlea, and stimulates draws on the expertise of a variety of have severe side-effects. Although the the auditory nerves directly through disciplines such as computational and underlying principles are not clear, an implanted device. A microphone on experimental neuroscience, clinical DBS directly changes brain activity in a an external unit gathers the sound and neurology, electrical engineering and controlled manner, and its effects are processes it. The processed signal is then signal processing. Of special note is the reversible, unlike those brought about interface to living neural tissue, which transferred to an implanted unit that through direct surgical intervention. brings together elements from robotics, stimulates the auditory nerves through a In fact the effects of DBS on essential cybernetics, computer engineering, microelectrode array. tremor can be starkly seen when the DBS neural tissue engineering, materials system is switched off – the characteristic science and nanotechnology. In 2009, more than 188,000 people tremor returning within moments. worldwide had received cochlear While neural engineering still has a implants – many of them children. The Engineering’s strong research component, it has vast majority of implants take place in contribution some very clear and beneficial goals. developed countries because of the Like any other area in biomedical These are centred on the restoration high cost of the device, surgery and engineering, neural engineering is and augmentation of human function post-implantation therapy. Following highly cross-disciplinary and requires the via direct interactions between the recent advice by the National Institute for interaction of specialisms in engineering nervous system and artificial devices, for Health and Clinical Excellence (NICE) in example, restoring the ability to interact the UK, a growing number of recipients and in life and health sciences. with the environment following a stroke have bilateral implants – one implant in Developments in the neural engineering or debilitating neural disease through each cochlea. field could not happen without training in many areas of expertise. These include: before they start. This technique is ways to achieve non-muscular BCI by core training in electrical and electronic similar to that being researched in the capturing brain activity in real-time. engineering, specialist training in signal treatment of epilepsy – where the goal is EEG-based BCI systems require relatively processing and systems modelling, as to use DBS to stop debilitating epileptic simple and inexpensive equipment, well as computer engineering training seizures before they even start. should be portable and easy to set up, in computational intelligence and and should function in most real-world machine-learning. This needs to be Brainstem stroke, brain or spinal cord environments – but this is a non-trivial coupled with expertise in physiology, injury and numerous other muscle problem. neuro-anatomy, neurology, elements of wasting diseases such as amyotrophic chemistry – as well as advanced areas lateral sclerosis (ALS) result in the Conclusion degeneration of specific motor neurons such as nanotechnology. Neural engineering is an up and coming which causes muscles to stop receiving area within biomedical engineering. It movement commands. People suffering Neural engineering relies on biomedical addresses a wide range of debilitating from these disorders ultimately lose the engineering educational programmes illnesses and shows promise to address ability to control their muscles and to to produce graduates with the correct much more. It is an area which shows communicate while their intelligence, base skills to handle the unique clearly the benefits of multi-disciplinary memory and ability to think remain problems associated with restoring and research and the continued need to fund intact. Therefore, a healthy brain is augmenting human function through research and development at the life- “locked in” a paralysed body. As the direct interface with the nervous system. sciences interface. Continued funding French journalist, Jean-Dominique in this area will help to create new Bauby, has shown in his memoir The Future work businesses that exploit emerging neural Diving Bell and the Butterfly, which was engineering techniques, assessing and Areas under development and nearing composed letter by letter with 200,000 evaluating them and delivering them clinical application include the use blinks of his left eyelid after suffering through the most appropriate means. of functional electrical stimulation to from a massive stroke, establishing an control limbs following spinal injury alternative to neuromuscular interaction Author: Professor Christopher James, and neural interfacing to prosthetics to is a painstakingly challenging day-to-day Director, Institute of Digital Healthcare, control artificial limbs. Other areas under venture for severely impaired people. research include ocular implants to University of Warwick restore sight to the visually impaired and Consequently, neural engineers the use of brain-computer interfacing have been attempting to develop to restore communication to those who systems that enable these patients to lack the ability through stroke, severe communicate with computers directly Contact brain disease or spinal injury. through brain activity rather than by For more information please contact: physical means. Such systems are Within neuroprosthetics, research meant to provide new, non-muscular Katherine MacGregor is being carried out with the aim of channels of communication – a brain Policy Advisor predicting the onset of tremors before computer interface (BCI) for conveying The Royal Academy of Engineering they occur by monitoring activity deep messages and commands to computers. Tel: 0207 766 0623 in the brain. The specific goal for doing Electroencephalography (EEG), this is to provide stimulation only when measuring brain activity from the scalp, [email protected] needed, to stop any tremors occurring and related measurements are possible

January 2011 Neural engineering