Our perception of reality is a fragile entity when one considers the effects of aging, drugs and injury onto the brain. There can be, at times and even among the unimpaired, a thin line separating what we perceive to be true and what, in fact, is true. One philosopher describes our perception of reality as "the show between our ears," and as unfortunate as it is, one can duly note that some of us the channel has been changed. Some choose this altered state of reality through drug use, escaping, at least for a while, the pain of the "reality." Many individuals, however, have altered states of perception forced upon them- usually through the effects of aging or genetics. Alzheimer's disease and Schizophrenia are the more serious thought disorders that alter states of reality. Both have its roots in genetics, with Alzheimer's disease increasing in severity with age.
Considering the complexity of the brain, it is perhaps remarkable that it performs so well, for so long. There is no doubt that the evolution of the brain, and with it a vested interest in our greatest competitive advantage, succeeded magnificently. It is also easy to recognize, that until modern medicine, how those individuals that drifted from "reality" failed to survive long in a real world- and did not suffer long under "false" perceptions.
That has indeed changed, and nothing is more heartbreaking than those suffering from the effects of mental disorders. I cannot help but to consider Descartes' cogito and wonder about those who can no longer perceive our sense of reality. Perhaps the greatest fear for most of us, as we age, is the loss of our minds- as nothing more than our thoughts, emotions and memories better defines us. Anyone who has cared for someone with Alzheimer's can certainly relate to the emotional challenges of dementia and the loss of someone we used to know. And, painfully, their loss of perception sometimes challenges ours.