Abstract :
For those over 40, it??s not unusual to begin to find it difficult to see nearby objects. But many can avoid–at least for a while–the hassle and expense of prescription lenses by buying a pair of cheap off-the-rack reading glasses from a drugstore. Hearing declines with age as well, but unlike with vision there hasn´t traditionally been good intermediate technological assistance between simply turning up the TV volume and getting a hearing aid, which can cost US $4,000 and up. In recent years, a number of companies.