After two years of worsening symptoms, the Kargers found Dr. Murray Grossman at the University of Pennsylvania. Dr. Grossman is short and charismatic, a quick-witted Montreal native who has mentored me since I began training in neurology. For the past several decades, he has pioneered research on neurodegenerative diseases that change behavior and language. When he saw Mr. Karger in 2007, the diagnosis was clear within the hour: Mr. Karger had a type of frontotemporal dementia.

Frontotemporal dementia attacks people in their fifth or sixth decade, just as retirement comes within reach. Doctors believe the disease affects 60,000 people in the United States alone. Neurons in the front and side of the brain wilt, and along with them, images of peacefully growing old fade. Judgment and complex planning yields to chaotic disorganization. Inhibitions give way to impulsivity and hypersexuality, so that longtime faithful partners look to affairs and excessive pornography. Empathy turns to apathy. Obsessions and compulsions erupt. Language can become laborious; the meaning of words and objects can be lost, and fluent speech can dissolve into fragments of sentences with nonsensical grammar. Jarringly, memory remains largely untouched. Since brain areas that dictate personality are often the first to suffer, most people end up on a therapists couch long before finding their way to a neurologist.

In the throes of the disease, many families seek out others who might be experiencing something similar. The support group is helpful, because this can be a very lonely thing, said Ms. Karger, now 80, who is a co-leader of a support group for caregivers of those with frontotemporal dementia. She paused, then repeated, it can be very, very lonely.

When I visited Ms. Kargers support group this spring, members shared practical advice. Im having trouble getting my wife to shower, one man said, describing a common manifestation of apathy. Its been five weeks. Another man said he gets his wife to bathe by putting her toe or finger under the faucet first, so the wetness doesnt feel as foreign. A third person recommended giving up altogether in favor of dry shampoo and baby wipes.

A man asked about obsessions. With a tinge of humor, people recounted items their partners had fixated on: organizing glasses at a family wedding, aligning dirty dishes at Panera, fluffing pillows. You could be bleeding to death, and all shed want to do is rearrange the pillows, another man said.

The rest is here:
The Loneliness of Frontotemporal Dementia - The New York Times