I WAS staring straight ahead at the Romper Room set, the big block letters -- J K L M N -- on the wall. Any minute I expected to see Upoff round the corner ("I'm sick. Could you call me an ambulance?") followed by Granny ("OK, you're an ambulance"). My host, sedately poised amidst pastel cushions, was asking me about schizophrenia and I was trying to pay attention, but my brain was disconnecting because schizophrenia just does not belong in the Romper Room. I wondered what would happen if I stopped and told television viewers that we were really in the Romper Room, but they could see only pastel pillows and a fake fireplace and would think I was trying personally to demonstrate the disease we were discussing.

This was only city number 3 out of 16 on the book tour. By the end I was ready for anything, for on various shows I had been preceded by a 6-year-old clown, a woman demonstrating how to firm flabby thighs, a pasta salad (the "super bargain of the week"), the worst-Irish-tenor contest, a sewing demonstration on making covers for toilet paper holders, and a summary of gossip items from the soaps. Competing with the inside story of Angie's pregnancy or Rachel's amnesia is tough enough, but how do you get a viewer interested in schizophrenia when he has just learned why Heather agreed to sleep with Tucker?

The acts got tougher as the cities rolled on. In Houston I followed Curly Neal of the Harlem Globetrotters. There he was, rolling the ball over his head and shoulder as if it were magnetized; panic seized me when I realized that the show's host might throw the ball to me as I walked on. Or in San Francisco when a male fashion show ("stylish white jacket, just right for summer, only $420," rolling the r's of the dollars) and then a men's body-building demonstration immediately preceded me. I watched from the wings, caught between Scylla and Charybdis. If I left my jacket on, my fashion proclivities ("Smart blend of Sears and Woodies, perfect for the Metro") would be obvious, but if I took it off, my pectoral underdevelopment would be on display to the entire Bay Area. I compromised by hunching over, pretending I had a bad back.

Marshall McLuhan noted years ago that radio and television are vastly different media, and people in the business provide ample demonstration. The medium -- and the maximum -- is the message. Radio is all voice, with station employes casual, laid-back, and dressed for Saturday yard cleaning. On more than one occasion, I was greeted in the waiting room by a man or woman who beckoned me to follow, and it was not at all clear whether the person was the talkshow host or a janitor. In Boston I still was not certain until we sat down in the studio and my host launched into a hypomanic monologue with resonant voice like the Big Bopper of yesterday -- "I haaate to say it folks but the weatherman is calling fooor sno-oo-oo- ow now" -- all the while shuffling ads on cassettes into playing slots and firing questions at me. In the television studios, by contrast, it is all looks. Even the woman at the reception desk looks as if she sleeps at Elizabeth Arden. Cropped hair and asymmetrical arrangements surmount the layered look while Bill Blass, Ralph Lauren and Oscar De La Renta vie for prime time. The total quantity of hair dye and makeup in use in any given television studio is sufficient to trigger a smoke alarm in the National Cancer Institute.

The stations themselves also have personalities. In Philadelphia I was interviewed by an erudite host on an FM classical music station located in a book-lined museum office. Near Chicago, by contrast, my host was a cigar- smoking redneck who interviewed me between plugs for the Liberty Lobby; outside pickup trucks outnumbered cars three-to-one in the station's parking lot. My host in Detroit was Sonya Friedman, who had recently published her own book called Men Are Just Desserts. I briefly considered dressing as a butterscotch sundae but thought it might look inappropriate for a psychiatrist.

Almost always there were other guests waiting to be interviewed. There are between 50 and 100 authors touring the nation's radio and television studios on any given weekday, for Random House, Simon and Schuster, Harper & Row and the other publishers have learned that media talk means sales. We waited together in the guest rooms, chatting amiably over coffee and Danish while mentally denigrating the other person's book. In Los Angeles there was a fat lady selling a diet book. The soft sell, I thought. Although nobody seemed much threatened by my book on schizophrenia, there was always room for a putdown if you were forced to come second on a show where you expected to be the first guest. One author who maintains a year-round home on the bestseller list looked perturbed when told he would follow me on a show in Cleveland. Looking up brightly, he exclaimed that his books had now sold more than 30 million copies. I smiled weakly and congratulated him. The danger of telling another author what you think of his books is that you may be on the same flight to Detroit with him that evening.

Perhaps the most memorable guest scene was in Boston, where my television interview was to be sandwiched between a segment on children's dolls and another on Boston's safest suburbs. Excited 6-year-old girls filled the waiting room, each clutching a doll and being zealously guarded by a mother who seemed convinced that Hollywood was but a short step away. In the midst of this ebullience sat a somber man who looked as if he were going to interview for a job as a mafioso; perched prominently on his knees was a book on mass murderers. Mothers kept glancing at him as they subtly tried to steer their emergent starlets away from his vicinity.

Schedules are often tight to impossible, and I came to welcome airports where I could accurately predict the location of the men's room. To whisk authors to as many as six radio and television interviews a day, publishers hire local "drivers" who chauffeur you around and get you to the airport on time. The drivers are mostly women working part-time, and they could write their own books about what-famous-author-X-did-last-month. Survival as a driver demands discretion, but one could not resist telling me about the author of a book on alcoholism who got drunk over lunch and proposed that they spend the afternoon in his hotel room rather than his going on to do shows in Chicago.

ANOTHER ASPECT of the book tour is the telephone interview for radio talk shows. These can be donerom your home or hotel room, or they may be scheduled for strange hours between interviews on the road, so you must find a telephone. Telephone booths are going out of style, and at the Dallas airport I had to make do with a bank of wall telephones at the end of a deserted corridor. I launched into a lively discussion on schizophrenia with Jim Aiken of Southern Baptist Radio, and as we talked the telephones filled up one by one. I became increasingly self-conscious as those around me glanced over their glasses to see whom I was talking to ("That's a good question, Jim. You see, most schizophrenics are not dangerous but occasionally one will become violent"), and when I hung up and left, I felt eight pairs of eyes follow me. There is also the excitement on call-in shows of not knowing who may recognize you and call; on a telephone interview with an Iowa station, my wife's aunt (whom I had never met) called to introduce herself.

As the cities slipped by, it became a battle between surrealism and ennui. I would emerge off the streets into a studio, briefly become a disembodied voice or image floating through the air by some mysterious process and picked up by people in their homes and cars doing Lord-knows-what, tuning in and out even as I was speaking, nodding agreement, mocking me, swearing at me. Then I was back on the street, looking up to see if my voice or image might still be hanging there, or at least a grin like the Chesire Cat's.

On the other hand there were the same questions, day after day. The challenge was to look as if you were answering them for the first time. I devised a strategy of pausing briefly as if to consider, then beginning, "Yes, that's a good question, Max. Schizophrenia is often confused with a split personality, but they're not at all the same thing." Max was usually pleased because he looked smart, and the listeners were pleased because Max had asked the question on their minds. After the fifth time the same day, however, I found it difficult to suppress an urge to say: "Look Max, it's been a long day, and I'm really sick to death of talking about schizophrenia. Why don't we surprise your listeners and talk about the N.B.A. playoffs?" The urge was stronger on shows we were taping for a 6:30 a.m. Sunday morning slot in which the listenership would be confined to 27 young men driving home from their girlfriends' apartments and who were too tired to turn the dial. When boredom threatened to produce acute brain-fog -- when one's brain just stops in first gear and refuses to shift -- I mentally composed postcards to the nine publishers who had rejected my book as not commercially viable.

Of all the surprises on the tour, the biggest one was that there are interesting people living in many of the cities between the coasts. For an inveterate coast-liver who has become accustomed to thinking of the middle nine-tenths of the United States as a full-length feature film following dinner, it was a revelation to find thaSt. Louis has more than brewery workers, Cleveland more than Indians, and Minneapolis more than script writers for Prairie Home Companion. In fact, it was such a surprising finding that I may write a book about it. If I don't have to go on tour.