October 6, 1985

A DIAGNOSTIC and resource center for Alzheimer's disease opened at Rutgers Medical School here last week, the first step in a statewide effort to coordinate and improve services for about 200,000 New Jerseyans who suffer from the fatal, degenerative brain disorder. Officials of the new state-sponsored facility say that it will offer specialized medical and social services for Alzheimer's patients and their families, as well as educational and research opportunities for doctors and other health professionals. ''There is no cure for Alzheimer's, but manifestations of the disease can be much better managed than they usually are,'' said Lee Joslin, director of the center, the Institute for Alzheimer's Disease and Related Disorders. ''Our intention is to help professionals learn to treat the symptoms in order to reduce the stress on Alzheimer's patients and their families.''

A 54-acre forested area less than four miles from downtown White Plains is the site for a $40 million residential community that will have 97 attached and free-standing homes. To be known as Wrenwillow, the development, situated between Rosedale Avenue and the Hutchinson River Parkway, will be a homeowners' association, which, unlike a condominium community, allows buyers to take title to the property under and immediately surrounding their homes.

The Metropolitan Museum never hesitates to think big, as we all know. Thinking big is not always such a great idea, but there are times when thinking big, thinking straight, and thinking brave are one and the same thing, and one of them will come about on Saturday, Oct. 26, when the very large loan exhibition called ''Liechtenstein: The Princely Collections'' opens to the general public after several weeks of members' previews. ''Thinking big'' can sometimes be taken literally, in this context. The great late Rubens altarpiece, ''The Assumption of the Virgin'' may well be the largest Old Master painting ever to be brought into the Met. (Before it could be got safely inside, it had to be uncrated in the street. Door frames had then to be removed, and walls to be taken down.) But in the end it is not, of course, the dimensions of the ''Assumption'' that count. (To be precise, they are 198 1/2 inches by 138 5/8 inches). It is the fact that this is Rubens's last and largest account of a subject to which he had returned again and again. It is also relevant that no comparable Rubens has ever been seen, or can be seen today, in this country, and that the ''Assumption,'' though shown briefly in Lucerne, Switzerland, in 1948, has not been seen in public since, and has recently been cleaned for the present exhibition with entirely happy results.

Deeply in debt and with less than $1,000 in its bank accounts, this steel city laid off its entire 14-member police force and 10-member fire department in early September. ''We've cut the fat to the bone and now we have to cut essential services,'' Mayor Daniel Pastore said. ''We're broke. But what's the point in filing for bankruptcy? You've got to pay your bills anyway. We've got to show the banks we're doing something and then they'll talk.''

Housing Finally Starts Housing starts have been a disappointment this year. With mortgage interest rates down, housing activity should be up. Instead, housing starts soared to an encouraging 1.9 million unit annual rate in April and never hit that level again. But Rosanne Cahn, of Goldman Sachs Economics, says that housing may still wind up the year on the strong side of the ledger. She expects starts of single and multifamily housing units to total 1.85 million for 1985, solidly ahead of last year's 1.75 million units. The September number, due out next week, will show the housing sector's growing strength, said Mrs. Cahn. She expects a 6 percent jump in starts over the August level, the second strong monthly rise in a row. Michael Carey, of Citicorp Investment Bank, is also optimistic about this key sector. ''We expect housing starts to continue to rise through the fourth quarter,'' he said, as lower mortgage rates and gains in real personal income encourage home building and buying.