NONFICTION - March 29, 1987

A CLIENT CALLED NOAH by Josh Greenfeld (Holt: $18.95; 371 pp.). Noah Greenfeld is severely brain-damaged. His official diagnosis is autism; unofficially it’s hell. In “A Client Called Noah,” Josh Greenfeld, Noah’s father, writes of the imminence of placing Noah in either an institution or a residential facility.

This completes a trilogy of books that noted screenwriter Greenfeld (“Oh God! Book II” and “Harry and Tonto”) has written on the love-hate relationship between father and son. The others dealt with the questions about Noah’s future; Noah’s future is here.

Greenfeld’s candor and acerbic wit make the book at once unflinchingly honest and droll: “I’ve spent Father’s Day wondering how I could kill Noah and hang the rap on Karl (Greenfeld’s other son).” Karl’s rite of passage through adolescence ushered in by bad grades, drug experimentation and deriding his parents, might have been intensified by his brother Noah’s condition and the attention he commanded. Karl would baby-sit for his parents when they went square-dancing, he volunteered to work at the day care center for handicapped children that the Greenfelds started, and when it came time to place Noah in an institution, it was Karl objected to Noah’s having to leave home.

Greenfeld and his wife, author Foumiko Kometani, try just about everything in an attempt to accelerate Noah’s microscopic development--from starting their own day care center, to learning sign language and even purchasing another house where Noah lived with an attendant--all to slow down impending placement in an institution. Often their only rewards were Noah’s assaults of spitting, pinching, scratching and hair pulling. His tantrums and rages work to make his simplest needs known. For all the turmoil Noah’s conditions heaps upon the family, Greenfeld cannot ignore the ironic fact that it is Noah who “is the linchpin that holds us together.” And the wedge that drives them apart.