The nineties were supposed to be the decade of the brain. And scientists worked hard to unlock its mysteries. So now are we any closer to understanding the mind? Not even remotely. In this hour of To the Best of Our Knowledge, can the human brain ever figure itself out? Also, head transplants. And, living with Alzheimer's — John Bayley remembers the last days of Iris Murdoch.

Science writer John Horgan tells Steve Paulson that the more we discover about it, the less we understand the human brain. Horgan's latest book is "The Undiscovered Mind: How the Human Brain Defies Replication, Medication, and Explanation." Also, neurosurgeon Robert White talks with Judith Strasser about the prospects for transplanting human heads. White says it's a logical development as medicine explores replacing organs with machines or animal parts, and would be of great benefit to patients whose lives have been destroyed by brain failure. White is a neurosurgeon at Case Western Reserve University in Cleveland.

Jonathan Lethem talks with Jim Fleming about his new novel, "Motherless Brooklyn." The book tells the story of Lionel Essrog, a private detective with Tourette's Syndrome. Also, John Bayley, husband of the late Iris Murdoch, and author of the best-selling "Elegy for Iris," has a new book - "Iris and Her Friends." The book describes Murdoch's final days with Alzheimer's disease. Bayley talks about both books with Steve Paulson.

Distribution dates:

• week of 12/19/99 - hour 2