By Laura E. Perlini, Frontiers

The first evidence of the capacity of the human being to conceive and manufacture an object that could replace a malfunctioning part of the body is dated between 1295 and 664 B.C. It is the “Greville Chester Great Toe”: a prosthetic toe made using linen, glue, and plaster. It was supposed to aid people who had lost their toe to walk or balance.

From ancient Egyptian times, much progress has been made, and nowadays, we are able to make devices that replace or supplement the input and/or output of the nervous system and could ideally bypass neural deficits caused by a disease. This type of prosthesis is called “Neuroprosthesis.”

In particular, “sensory neuroprostheses” are able to convert environmental stimuli into perceptions by capturing external inputs and translating them into appropriate stimuli (usually electrical) to the nervous system. The most representative success of sensory neuroprosthetics is the cochlear implant, used in rehabilitating neurosensory hearing loss. The success of cochlear implants has boosted the interest of the scientific community for sensory neuroprosthetics: the concept of using electrical stimulation to provide sensory input to the brain is now being investigated to restore all the five senses. Currently, retinal implants, vestibular implants, deep-brain stimulation devices and many others are being developed by scientists.

Sensory neuroprostheses also represent an unprecedented platform to investigate sensory processing in the brain, facilitating the acquisition of fundamental new data and increasing the current knowledge of sensory deficits and multisensory integration. Recently, also the effects of sensory neuroprostheses on the development of the nervous system and on cognitive functions have become important research topics.

To spotlight the importance of Sensory Neuroprosthetics, we interviewed Doctors Perez Fornos (University of Geneva), and Van de Berg (Maastricht University Medical Centre). Both doctors work on vestibular implants and have recently launched the Frontiers Research Topic “Emerging Sensory Neuroprosthetics: Feasibility, Efficacy, and Metrics” in collaboration with Doctors Guinand (University Hospital Maastricht), Kingma (MUMC / UM), Senn (University hospital of Geneva ) and Desloovere (University Hospital Leuven).

 Why did you choose this area of research? Why are you passionate about this Topic?

Dr Perez-Fornos: The aspect that fascinates me the most is that sensory neuroprostheses can change patients’ lives and at the same allows peeking through an unprecedented window to how the brain interprets peripheral sensory information.

I started working in the field of vestibular implants in 2011. Vestibular diseases are disorders of the body’s balance (vestibular) system. They are poorly understood and underestimated, with practically no therapy options. I was immediately fascinated by the potential of vestibular implants: they seem feasible and promising. The vestibular implant allows providing a “vestibular-only” signal to the brain without activating the other sensory modalities involved in balance and equilibrium. They also permit the investigation of the vestibular function in an unprecedented way and the study of how the brain processes and integrates multiple sensory cues to ultimately generate conscious perception and reflexive behavior.

Dr Van de Berg: Vestibular research combines many different subspecialties like ear nose throat (ENT)-surgery, neurology, psychiatry, ophthalmology, and physics. It is a challenge to combine all these aspects, and I like challenges!

Dr Perez-Fornos’ collaborators. From left to right: Dr Nils Guinand, Prof Jean-Philippe Guyot, Prof Marco Pelizzone, Maurizio Ranieri, Samuel Cavuscens and Dr Perez-Fornos

A vestibular implant (reproduced with permission. Source: Medical Visuals)

Why is it important to focus the attention on this topic now?

Dr Perez-Fornos: Several disciplines are involved and need to interact for the success of sensory neuroprosthetics. For instance, probably one of the key points for the success of cochlear implants was the ability of the pioneers in the field (physiologists, physicists, engineers, surgeons, therapists) to work together.

Although the patient population and the application of each neuroprosthesis might be different, they share many common principles and often face similar hurdles. The aim of this topic is to serve as a privileged platform for exchanging on common issues to facilitate and accelerate developments.

In addition, we expect our topic will also serve as an important information channel to boost knowledge and interest in the field. We should step up and appropriately inform the general public and the scientific community about sensory deficits, the burden faced by patients, and the potential for rehabilitation so that the importance of the development of these devices becomes clear.

Dr Van de Berg: At this moment, neuromodulation is a hot topic for all sensory structures. Techniques are improving so fast that they make sensory neuroprosthetics more and more feasible for clinical use. For example, the vestibular implant seems close to becoming a clinically useful device in the relatively near future.

Dr Van de Berg’s collaborators. From left to right: Prof Robert Stokroos, Dr Van de Berg and Prof Herman Kingma  

Why did you decide to host a Frontiers Research Topic and what do you hope to achieve from it?

Dr Perez-Fornos: Frontiers is a major open access platform for scientific dissemination providing a uniquely fast and transparent review process. Only such a platform can set the necessary conditions for successful, unbiased, and balanced interactions between all disciplines involved in sensory neuroprosthetics. Furthermore, a far-reaching and long-lasting impact will be guaranteed by providing the whole community with access to these privileged exchanges. This is why we are convinced that a Frontiers Research Topic constitutes the perfect recipe for success in a time where interest in the field has been boosted by significant milestones as well as novel technological possibilities.

Dr Van de Berg: It is necessary that articles are reviewed by experts in the field and that as many clinicians and researchers as possible have access to all the latest developments. Based on my previous experience, the open-access platform of Frontiers suits this very well: it always facilitated honest and fast reviews and promoted the visibility of the published articles and the dissemination of the results.

We look forward to seeing this Research Topic completed. Submit your manuscript today.