Development of a cortical visual neuroprosthesis for the blind: the relevance of neuroplasticity

Abstract

Clinical applications such as artificial vision require extraordinary, diverse, lengthy and intimate collaborations among basic scientists, engineers and clinicians. In this review, we present the state of research on a visual neuroprosthesis designed to interface with the occipital visual cortex as a means through which a limited, but useful, visual sense could be restored in profoundly blind individuals. We review the most important physiological principles regarding this neuroprosthetic approach and emphasize the role of neural plasticity in order to achieve desired behavioral outcomes. While full restoration of fine detailed vision with current technology is unlikely in the immediate near future, the discrimination of shapes and the localization of objects should be possible allowing blind subjects to navigate in a unfamiliar environment and perhaps even to read enlarged text. Continued research and development in neuroprosthesis technology will likely result in a substantial improvement in the quality of life of blind and visually impaired individuals.

Real-time signal detection and classification algorithms for body-centered systems

“…Body-centered communication systems have many applications in the biomedical, telemedicine and entertainment fields [15], [16], [17], [23], [24] and [25], where obviously wireless technology presents many advantages. Such systems are designed using the so-called Wireless Body Area Networks (WBANs), which are made up of a set of mobile and compact intercommunicating sensors, either wearable or implanted into the human body, which monitor vital body parameters and movements.…”

“…Today's improved sensor technology, together with miniaturization of transmission and processing devices, allows the use of many sensors and in many locations on the body and also inside the body, which, in turn, results in a considerable data rate to be transmitted over the wireless link [17], [18], [19]. In the present, wireless sensor units are usually composed of the sensor itself, connected to a transmission unit by a small cable, as in the example of Security is also an important issue in WBAN for patient monitoring.…”

“…Studies conducted during the last decade have demonstrated the improvements that neural signal decoding will bring to health care, especially for patients suffering from paralysis [23], blindness [17] or deafness [149].…”

“…The Poisson model is valid if one assumes that each neuronal spike constitutes an independent random variable, which is not totally true but it yields to an approximation that suffices for the generation of additive noise, where the importance is not on the exact spiking times but on the fact that the resulting noise resembles the real neuronal noise present in micro-electrode recordings. The number of noise neurons taken for noise generation is an approximation based on the assumptions that: only neurons within 140μm of the electrode are detectable and that the density of the motor cortex is 30.000 neurons/mm as stated in [17]. A scheme of the procedure is shown in Figure 22.…”

“…Additionally, in order to ease the fitting process, the CCDF exp is log-scaled so that Λ can be obtained by means of a linear fit as shown in (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20).…”