Yesterday, I wore my reporter’s cap in this space, writing about Scooter Libby’s putative cognitive deficits. Today, in the middle of my book tour, I’m going to try to catch up with myself. As of this morning, Carved in Sand is on the shelves of nearly every bookstore in America. A feature story about my journey appears in USA Today. For a slew of reasons, that is amazing. A decade ago, my cognitive firepower was definitely on the wane. As I write in the first pages of the book, “Something was happening to my mind. I felt vague and foggy. I couldn’t remember what I’d read for much longer than it took to get to the bottom of the page.”

I was suffering from something – but I couldn’t name it. I thought that maybe I’d lost my edge -- a sad thing at 40, especially when the career I loved – investigative reporting and feature writing for magazines – depended largely on my ability to retain and synthesize information. I couldn’t think of anyone I could tell, so I kept my troubles to myself. If the same difficulties hadn’t cropped up a few years later among just about everybody I knew – irritating glitches involving proper names, elusive mental calendars – I might have stayed silent. Instead, I decided to make myself a guinea pig, exploring every possible intervention, in an effort to figure out what was going on upstairs.

When I decided to take on Carved in Sand in my mid-forties, my confidence in my mind had seeped away. The steel trap I’d possessed in my twenties and thirties had been replaced with a kitchen colander. Frankly, the prospect of tackling relentlessly complex subject matter – neuroscience, biochemistry, and genetics – made me woozy. For months, I went blind with anxiety when I scanned the dense pages of peer-reviewed professional journals that formed the basis of my research. But here’s what surprised me: My editors and agent were absolutely confident that I had what it took to pull it off. They produced contracts and proffered advances, carefully ignoring the facts that I’d laid before them in my book proposal: My middle-aged mind was behaving unnervingly. When, in the interest of full disclosure, I noted this, they might as well have clasped their hands over their ears.

Often (usually in the middle of the night), I wondered what had allowed these experienced professionals to take such a bold step. Did they not see what I knew too well – that someone had snatched the poles from my intellectual tent? When they talked to me and read my work, did they somehow encounter a smarter, more insightful version of me than I could find in myself? Couldn’t they hear me grasping for words, fudging conversations when proper names disappeared, arriving windblown and out of breath because I was looking for a building I’d been to several times – on the wrong block? Wasn’t it obvious?

Finally, I concluded that their interests were wonderfully selfish: They, too, were in middle age, struggling with daily episodes of forgetfulness. For them, I was a Russian monkey-cosmonaut: If I – who had the nerve to go public with my cognitive shortcomings – could find a solution, maybe they – and the whole middle-aged world -- could benefit.

Their confidence – which never flagged – worked miracles. They knew, certainly, that responsibility was (and continues to be) my middle name. It’s a known fact that I’m constitutionally unable to let anyone down. They knew that I was meticulous, even compulsive in my research – the nagging voice that tells me that something is still missing from the picture won’t shut up until I get to the bottom of a difficult question. But these traits – however laudable – wouldn’t have been enough to produce a book of the size and scope of Carved in Sand. They had no way of knowing that I’d be able to sustain a narrative for 265 pages, or that I could manage the many hundreds of interviews that were required, nor that, once the book was published, I could handle three media appearances a day for a month straight. They took it for granted that I possessed the mental filing cabinet that would allow me to produce nearly 500 full citations – the list of endnotes that appear on page after page at the end of the book.

In short, those editors and that literary agent made a wager. They banked on my brain – that it was still good enough, and that it would get better. They bet right: The very work of writing Carved in Sand was exactly the antidote I needed. The intense mental effort involved – which went on seven days a week, for over three years kicked my lazy neurons back into action. Some days, I swore I could feel it happening, the ebullience of the hook-up …synaptic connections zinging to life, new associations made, deeper understanding emerging.

In Carved in Sand, I write about new research that suggests that the best way to maintain your brain is to offer it relentless challenges. Get out of your routine, and take on something that doesn’t come easily. Take up chess. Learn salsa dancing. Get into a bridge game. Leave the microwave alone. Instead, shop for and cook – from a recipe – a complicated meal – and time it so you get several courses on the table in a timely fashion.Or, if you have four years, write a book.

I always loved that title – it’s Grace Paley’s. Yesterday, I experienced them first-hand. It happened so fast. Early in the morning, I was sitting at my desk, looking at a tour schedule that, to my way of thinking, included plenty of good stuff – bookstore readings, radio and print interviews and local affiliate TV tapings. The USA Today piece had just been published, and I was happy. Casually, I considered how best to pack my suitcase for my departure on Saturday night. At 9:30 a.m., I threw on some clothes and headed up the highway for a haircut.

The salon is a noisy place, and even if I could have heard my phone ring in my bag on the floor, I wouldn’t have answered it in mid-snip. I glanced at the screen as I paid my bill, and noticed that I had four voice mails – a lot for me. Before I crossed the parking lot to my car, the cell rang again, and my publicist asked where I’d been – she had big news.

“Getting my hair done,” I said.

“Well, that’s a good thing,” she said, “because you’re booked on Good Morning America, and you have to leave tomorrow.”

Months ago, when we sent GMA the publicity materials for Carved in Sand, we’d had high hopes, tempered with low expectations. This was my first book, and attractive as the subject matter was, it would be sheer hubris to think that I’d make it to the big time.

“Can you do it?” Camille asked.

“My calendar,” I said. “Let me think.”

In the course of writing the book, I learned that two places that I once successfully stored information – the figurative “back of my mind” and the metaphorical “top of my head,” (as in, “off the top of my head”) ought to be avoided at all costs. I have proven, again and again, that there is no longer any such place as the “back of my mind,” and anything that comes “off the top of my head” is bound to be seriously inaccurate.

“My older son’s birthday,” I wailed. “Thursday. And my younger son’s classroom performance of A Midsummer Night’s Dream. He’s Bottom.”

There was silence on the other end. I knew what she was thinking. Would I really give up an opportunity like this in order to celebrate a 17th birthday, or view a bunch of 7th graders reciting Shakespeare? We’d run lines for weeks, and the kid had the part down. I sucked up the guilt. Briefly, I bathed in it. Then, I told her to say yes, wondering all the while how I was going to leave on my tour three days early. I’d sorted out a few clothes over the weekend, but the to-do list that remained was legion. My husband would not be pleased. Two and a half weeks away was a great long stretch that had to be carefully planned and negotiated. Now, it had stretched to three.

Within minutes, GMA’s machine was in motion. Last second airline tickets (ooh, how much did those cost?), limousines, hotel rooms and media escorts were all in place. Suddenly, my publisher, HarperCollins, a company that had taken a “let’s wait and see what happens” attitude for months, loved me and couldn’t do enough. Overnight, it seemed that my professional life had been transformed.

At three in the afternoon, around the time I usually turn from working writer to full-time mom, another call came. GMA would like to send a producer and a camera crew to my house for some pre-taping – just a little interview and some B-roll footage. Could they meet me at home at 5 pm? That gave me two hours, and to be honest, I still hadn’t found a moment to take a shower. My hair, freshly conditioned with some expensive thing the stylist insisted I needed, hung limply. I was to dress casually, as I would if I were hanging around the house. I assured the producer that he did not want to see – ever – what I looked like when I was hanging around the house. Remarkably, my once-a-week house-cleaning service had been in just that morning, so at least I was not going to have to get out the mop. I called the kids and my husband, warning them of the tornado that was about to strike.

“Where are you?” I asked my elder son, when I reached him on his cell.

“On the way to work,” he said.

“Um, when you get home, there will be a camera crew from Good Morning America in the house,” I said.

Another moment of silence. Then, with the utmost cool, the kind that an about-to-be 17-year-old musters better than anyone else: “O….kay, then.”

The crew turned up on time, and instantly, it was a party. Our two dogs assumed that the crew was there to film them, and began to bark insanely, while they chased each other from kitchen to dining room to living room. To escape, I suggested that we get some footage along the walking path near my house, with San Francisco Bay in the background. Back at home, they taped a long cuddle session with my boys on the sofa, photo albums open before us. “We really do this,” I assured the producer. “It’s one of our favorite ways to remember things, especially when it’s going to be somebody’s birthday.” Around 9 pm, the crew departed. We all looked at each other, thoroughly exhausted.

“This means you’re not going to be here for my birthday, are you, Mom?” my older son said morosely. “What about my presents and my birthday dinner?”

I shook my head, and again the guilt washed over me. I’d never missed a family birthday celebration before. In fact, I’d made a big deal about how showing up for family events was not optional, looking ahead to the years when the guys would have wives. And a mother.

“I am very, very sorry,” I told him. “But this is important, for all of us.” Could I really expect him to understand? Was he that grown up? One look at his face told me that he was struggling. I invited him to bring a friend and meet me for the weekend in Los Angeles in a couple of weeks, where I’d be giving a reading.

“We’ll go out for a fancy dinner,” I said brightly. “We’ll have fun. It will be okay.”

In my book, CARVED IN SAND, I write about our inability to fend off distractions in middle age. One of my favorite research studies dealt with what one scientist called “the neural bouncer – just like the one outside the front doors of a nightclub, handling the velvet rope.” The way he described it, in youth, that bouncer does a really good job of determining what is allowed into your working memory, and what is turned away at the door. As you get older, the bouncer goes on more and more coffee breaks, and your mind, left unguarded, is subject to invasions from all sorts of riff-raff. Instead of concentrating on the project before you, you find yourself thinking about what to have for dinner.

I loved the metaphor, and I’ve used it a lot in radio and print interviews. That morning, just prior to my second appearance this week on Good Morning America, I was living it. Usually – because I know my neural bouncer quit long ago – I’m conscientious about keeping my environment as free as possible from distractions. Unlike some people, I don’t keep the radio or TV on while I’m doing other things, because they prevent me from thinking straight. I can’t even tie my shoes if there’s something intriguing on the Discovery Channel – that’s how bad it is.

The producer at GMA picked me up from my hotel right on time, and walked me across the street for hair and makeup. Once in the chair – TV blaring, (even I knew that it would be wrong to ask them to lower the volume on Diane Sawyer so that I could concentrate) the fun began. While the hairdresser crimped my limp locks, and the makeup artist swabbed and sponged away the dark circles under my eyes, producers surrounded me, dropped documents in my lap, and started asking questions about the frontal lobes and the hippocampus – which was spelled how? Was it correct to say….? My head buzzed. My shoulders ached. I couldn’t talk, because my lips were being glossed. I wished to shout: “Did anyone read my book? Because if you did, you ought to know that I can’t talk more than one person at a time!”

That was just the beginning. We tiptoed on to the stage, winding our way amongst the always-present mob of technical crew and talent. A polite young man reached gingerly inside my sweater to position the microphone. Once escorted to my chair on the stage, I tried to compose myself, but this was unlikely: Ms. Sawyer was on the set, ready to talk to me about our segment. Although the noise and bustle level in the room was astounding, Ms. Sawyer spoke in a very soft voice. I leaned forward to hear her, commanding myself to focus on her words, despite the fact that another young man had decided that the microphone had to be repositioned and again had a hand down my sweater. In the split second we had remaining, I tried to remember what I’d said yesterday on the show – otherwise, I’d be likely to repeat myself. I drew a blank.

Five, four, three, two, one – all was silence, and then we were on. A miracle: total, in-the-flow focus. No one there – no one in the world – but the two of us. I answered her questions. I think I smiled. I might have thrown in a joke. And then, as fast as it had begun, it was over, the stage was abuzz, and I was on my way out the door. I barely avoided the knife-sharp edge of a monitor, aimed at my forehead, on the way out. Everybody congratulated me on a really good two-part segment, and I thanked them, doing my best to carefully pack away, in my treasure chest of memories, all that had happened since this trip began.