the bionic ear, many bionic devices have emerged and work is progressing on bionics solutions for other sensory disorders (e.g. vision and balance). Bionic research has recently provided treatments for medical problems such as neurological and psychiatric conditions, for example Parkinson's disease and epilepsy. In 1997, Colombian researcher Alvaro Rios Poveda developed an upper limb and hand prosthesis with sensory feedback. This technology allows amputee patients to handle prosthetic hand systems in a more natural way. By 2004 fully functional artificial hearts were developed. Significant progress is expected with the advent of nanotechnology. A well-known example of a proposed nanodevice is a respirocyte, an artificial red cell designed (though not yet built) by Robert Freitas. During his eight years in the Department of Bioengineering at the University of Pennsylvania, Kwabena Boahen developed a silicon retina that was able to process images in the same manner as a living retina. He confirmed the results by comparing the electrical signals from his silicon retina to the electrical signals produced by a salamander eye while the two retinas were looking at the same image. On July 21, 2015, the BBC's medical correspondent Fergus Walsh reported, "surgeons in Manchester have performed the first bionic eye implant in a patient with the most common cause of sight loss in the developed world. Ray Flynn, 80, has dry age-related macular degeneration which has led to the total loss of his central vision. He is using a retinal implant that converts video images from a miniature video camera worn on his glasses. He can now make out the direction of white lines on a computer screen using the retinal implant." The implant, known as the Argus II and manufactured in the US by the company Second Sight Medical Products, had been used previously in patients who were blind as the result of the rare inherited degenerative eye disease retinitis pigmentosa. In 2016,Tilly Lockey (born October 7th, 2005) was fitted with a pair of bionic "Hero Arms" manufactured by OpenBionics, a UK bionics enterprise. The Hero Arm is a lightweight myoelectric prosthesis for below-elbow amputee adults and children aged eight and above. Tilly Lockey, who at 15 months had both her arms amputated after being diagnosed with meningococcal sepsis strain B, describes the Hero Arms as “really realistic, to the point where it was quite creepy how realistic they were.” On February 17, 2020, Darren Fuller, a military