Answer
With advancing age one's sense of smell diminishes in acuity. An important component of taste is the olfactory detection of odors. What has happened to Gertrude is that she has lost much of her sense of smell. Consequently, her sense of taste is not as sensitive or acute as when she was younger.
Presbyopia, the loss of elasticity of lens tissue, is partly why Gertrude cannot read with her usual facility. In addition, loss of visual acuity and decreased depth perception--also common with advancing age-- seem to have overtaken Gertrude. But Gertrude also has acoustic difficulties--buzzing in her ears and difficulty in hearing normal sounds. The buzzing, also known as tinnitus, is a common affliction of the elderly. The loss of hearing acuity may be due either to damage of hair cells in the spiral organ or degenerative changes in the acoustic nerve pathway
Work Step by Step
The sense of taste is mediated by both olfactory and gustatory receptors.
