One father put a pile of dried beans on the table. He took little pieces of the pile away as he gave his young son the following explanation of his grandfather's illness:

"Grandpop has a sickness that makes him act like he does. It isn't catching. None of us is going to get like Grandpop. It's like having a broken leg, only little pieces of Grandpop's brain are broken. He won't get any better. This little piece of Grandpop's brain is broken, so he can't remember what you just told him; this little piece is broken so he forgets how to use his silverware at the table; this little piece is broken, so he gets mad real easy. But this part, which is for loving, Grandpop still has left." From "The 36-Hour Day"

Fear of losing one's mental faculties is as pervasive as any human fear can be--perhaps as great as the fear of death, or as the fear of cancer.

In any company, mention of "Alzheimer's" elicits a nervous joke or two and a shudder, always a shudder.

"Because it's incurable," suggests Dr. Neal R. Cutler, chief of the Section on Brain Aging and Dementia, Laboratory of Neurosciences, National Institute of Aging. That is part of the specter, of course, but there is something else even more dreadful--perhaps the disintegration of that indefinable sense of self that makes each of us unique.

But it is not only the personal implications of Alzheimer's disease and other so-called dementias that are at last attracting the active concern of neuromedical research scientists and psychosocial experts. Alois Alzheimer in 1907 described a progressive deterioration of brain function that appeared to strike its victims in middle age, as opposed to the so-called senility of the very old. Scientists today, however, confirm that more than half of the dementias of old age do, indeed, stem from the ravaging and relentless brain rot Alzheimer first described.

As more people live longer, the incidence of this devastating illness will increase. According to figures from the National Institute on Aging, more than half of all admissions to nursing homes are Alzheimer victims. Scientists now believe that Alzheimer's disease, or complications stemming from it, is the fourth leading cause of death among old people. Care for the Alzheimer patient costs an average $17,000 a year. But that does not begin to count the cost in emotional upheaval, not only for the victim but even more for loved ones. Although it has been said that each case of Alzheimer's has a more or less devastating effect on at least three other people, the cost is incalculable.

Recent breakthroughs in brain research have shed light on some aspects of Alzheimer's disease and have identified a number of other causes for confusion, memory loss, withdrawal in older people. Some, now called "pseudodementias" can be treated. They may be caused by drug reactions or interactions, depressions, other illnesses, even vitamin deficiencies.

True dementias--the word means "deprived of mind"--also can be produced by viruses, as in a rare (and always fatal) disease called Creutzfeldt-Jakob or by the genetic disorder Huntington's disease, by Parkinson's disease, or multiple sclerosis. There is also Multi-infarct dementia, the blood vessel disease that used to be known, inaccurately, as "hardening of the arteries in the brain." In some of these cases new treatments can help forestall the ravages at least for a while, but for Alzheimer's the progression is still relentless.

Nevertheless, scientists and a burgeoning network of psychosocial support groups are optimistic that relief, if not cure, is almost at hand.

In a program conceived by Dr. Robert N. Butler, former director of the National Institute on Aging and now chief of the department of geriatrics and adult development in the Mt. Sinai School of Medicine in New York, NIA is launching a concentrated effort on all aspects of the ailment from the afflicted brain cell to the disrupted family.

Neal Cutler and NIA social worker Angela M. Moore are recruiting, analyzing, guiding and advising 80 victims of Alzheimer's and their families. Their program is designed both to serve the public and to further research. A new drug study scheduled to get underway later this month includes experimental treatment for patients in the earliest possible stages of the illness and concentrated psychosocial counseling and support for families.

Much of the work will be trying "to characterize and define stages" of the disease. A mammoth task, says Cutler, because of "amazing" variations in functioning among people with approximately the same degree of illness. Unlike other experimental programs, NIA will continue medication for those patients who respond well, even after the study--now slated for five months--has been completed.

Characteristic changes in brain cells can distinguish Alzheimer's from otherwise similar illnesses, but the telltale twisted and tangled nerve cells and bits of nerve material can be seen by microscopic examination of brain material, either through a biopsy, a radically invasive procedure, or through autopsy procedures after death. Because there does appear to be some familial pattern to the illness, many families with brain-impaired elders are seeking autopsies for their deceased relations. Alzheimer support organizations endorse them, although all agree it is "a ticklish" area.

Highly trained specialists usually can make a diagnosis with up to 70 or 80 percent certainty through clinical analysis, mostly by eliminating all the other things that might be causing the symptoms.

But, Neal Cutler notes, too many doctors tend to dismiss the symptoms as the "normal" deficits of getting old. And too many others label all impairment as Alzheimer's without making any effort to determine if a more easily treated disorder may be the real cause. Victims, their families and often even their doctors want to deny as long as possible that the illness exists in a given person.

"We have one patient now," says Moore, "who has been sick for 10 years. He's 70. For five years he and his wife went for marriage counseling before he was diagnosed. They were told it was the onset of his retirement that led to the changes in their relationship and the difficulty with their adolescent children. They were recommended for family therapy . . . for five years."

In the beginning, most of Alzheimer's attendant anguish lies within the person. "In the early stages," says Cutler, "the victim may have some insight into the fact that he or she is forgetting, and that's very painful. In fact, for a while it is an ever-living horror. Then they pass that stage and just feel that something is amiss . . . And then it begins to get harder on the family."

Indeed, at the very moment the Alzheimer victim is about to become most dependent on family, the illness produces personality changes transforming him or her into the least lovable creature imaginable.

"It is," says Cutler, "very characteristic that these folks become paranoid, very suspicious, delusional, hostile, irritable. They may insist on performing tasks, financial transactions, driving, long after they are able to do so."

Moore puts it this way: "It's one thing to care for a person who appreciates you and your care, someone who is appreciative of your difficulties, but now you're taking care of a person who fights you, who is resistant and suspicious of everything you do, because the person you once knew and loved is no longer there . . ."

The NIA program does offer some hope, both because it focuses on a way to at least ease the illness and because it recognizes the burden on the family.

"When you think about it," says Moore, "people come in and bring their family member, knowing full well that there is no treatment yet, and no cure. But still in the back of their mind is the hope that just maybe something will be better. And I think, in fact, some things are better, not the dementia, maybe, but their ability to cope with it."

Persons of any age who may be in the early stages of Alzheimer's disease or who have definite memory deficits may apply to the NIA program by writing: Angela M. Moore, Section on Brain Aging and Dementia, National Institute on Aging, Building 10/Room 10N314, 9000 Rockville Pike, Bethesda 20205 or phone (301) 496-4754.