Remember : The Science of Memory and the Art of Forgetting by Lisa Genova


            Picture a penny in your mind’s eye. Because you’ve probably encountered a penny hundreds if not thousands of times over the years, you should have no trouble remembering what one looks like. You’ve committed this image to memory.

            Or have you? Which president is pictured on the head of the penny? What direction is he facing? Are you sure? Where is the date? The words liberty? in god we trust? What’s pictured on the tail side? Could you draw both sides of a penny with total accuracy from memory right now? How can you both remember a penny and yet remember so little about it? Is your memory failing?

            It’s not. It’s doing exactly what it’s supposed to do.

            Your brain is amazing. Every day, it performs a myriad miracles—it sees, hears, tastes, smells, and senses touch. It also feels pain, pleasure, temperature, stress, and a wide range of emotions. It plans things and solves problems. It knows where you are in space so you don’t bump into walls or fall down when you step off a curb to cross the street. It comprehends and produces language. It mediates your desire for chocolate and sex, your ability to empathize with the joy and suffering of others, and an awareness of your own existence. And it can remember. Of all the complex and wondrous miracles that your brain executes, memory is king.

            You need memory to learn anything. Without it, information and experiences can’t be retained. New people would remain strangers. You wouldn’t be able to remember the previous sentence by the end of this one. You depend on memory to call your mother later today and to take your heart medication before you go to bed tonight. You need memory to get dressed, brush your teeth, read these words, play tennis, and drive your car. You use your memory from the moment you wake up until the moment you go to sleep, and even then, your memory processes are busy at work.

            The significant facts and moments of your life strung together create your life’s narrative and identity. Memory allows you to have a sense of who you are and who you’ve been. If you’ve witnessed someone stripped bare of his or her personal history by Alzheimer’s disease, you know firsthand how essential memory is to the experience of being human.

            But for all its miraculous, necessary, and pervasive presence in our lives, memory is far from perfect. Our brains aren’t designed to remember people’s names, to do something later, or to catalog everything we encounter. These imperfections are simply the factory settings. Even in the smartest of heads, memory is fallible. A man famous for memorizing more than a hundred thousand digits of pi can also forget his wife’s birthday or why he walked into his living room.

            In fact, most of us will forget the majority of what we experience today by tomorrow. Added up, this means we actually don’t remember most of our lives. How many days, in full, specific detail, can you remember from last year? Most people recall an average of only eight to ten. That’s not even 3 percent of what you experienced from your recent past. You remember even less from five years ago.

            And much of what we do remember is incomplete and inaccurate. Our memories for what happened are particularly vulnerable to omissions and unintentional editing. Do you remember where you were, who you were with, and what you were doing when President Kennedy was killed, when the space shuttle Challenger exploded, or when the Twin Towers collapsed on September 11, 2001? These recollections for shocking and emotional events feel vividly remembered even years later. But if you’ve ever reminisced about that day or read or watched a news report about it, then I’d bet every penny I’ve got that your confidently held, highly detailed memory is loaded with stuff you never actually experienced.

            Accuracy aside, what does your brain remember?

Your first kiss

            The answer to 6 × 6

            How to tie your shoes

            The day your son was born