Being able to store and retrieve information keeps people from having to constantly relearn everything by enabling them to build on previous knowledge. Therefore, memory is related to intelligence. Remembering is a skill toddlers develop with maturity and practice. Remembering is a two-step process: storing information in the brain, then plucking it back out of storage.

There are two types of memory: short term and long term. Most everyday information goes into the short-term memory bank, where it remains briefly before disappearing. If information is repeated often enough, it gets moved from short-term memory into long-term memory, although a single, very intense experience sometimes creates an enduring memory.

The average adult can store about seven bits of information in short-term memory at a time — the length of a phone number. Because they have spent years encountering the same information again and again, adults have transferred massive amounts of data from short-term memory into their long-term memory. Therefore, they can readily recall amazing amounts of information, such as which bureau drawer holds the socks or that the plates are kept in a particular cabinet.

Toddlers can have trouble retaining more than two bits of data. All of the thousands of bits of information toddlers encounter each day are still very new to them. Until any given piece of information is repeated often enough to be transferred to long-term memory, toddlers will continue to forget many things that parents consider very basic. Because they will find some objects and experiences particularly impressive, they will also remember small details that may surprise parents.

Fragile Memories

Although toddlers are able to remember more with each passing month, their memories remain fragile. “But you must remember Jonah. You played with him just last week,” a parent tells her daughter. But no, she doesn't seem to remember. And when she sees Jonah again, she is as shy as if she were meeting him for the first time. Yet this same child remembers seeing the big green truck in the grocery store parking lot for ten seconds two weeks ago. Moreover, the ghouls and monsters that flitted across the TV screen when she was two suddenly come back to haunt her at age three, even though she didn't seem to be affected by them at the time and hasn't seen them for months.

By twelve months of age, an area of the brain called the hippocampus enables toddlers to remember events that occurred a few hours or a day before. And between twelve and eighteen months, children can engage in deferred imitation; that is, repeating someone's behavior hours, days, or weeks later.

False Memories

Memories not only slip away from toddlers with amazing ease, but it is easy to implant false ones in their highly impressionable minds, according to research reported in the journal of Consciousness and Cognition (1994) and the American Journal of Psychology (1998). For instance, when researchers told three- and four-year olds that an alligator had been eating an apple on an airplane, and later asked the children if they'd ever seen such a thing, they not only insisted that they had, they filled in the details:“He was under my bed and he was a pet and then when we was on the airplane he licked me right here[gesturing to a spot on his thigh].”

Toddlers are easily manipulated. If parents falsely accuse their youngster of having done something wrong, the toddler may believe she in fact is guilty and end up apologizing! In conducting interrogations, ask your toddler a question once and live with whatever answers you get. If you ask a second time, you may get the answer you expect, but it's not likely to be more reliable.

Familiar Comforts

Since toddlers' poor memories make even things they've been exposed to many times seem new and different, their love of rituals and predictable routines is understandable, as is the tenacity with which they cling to familiar blankets, toys, and pacifiers. Just as adult travelers long for the comfort of familiar food after spending a few days surrounded by the heady stimulation of strange environments, recognized objects and routines offer toddlers a welcome respite by serving as comforting anchors.

Further, repetition helps toddlers move information into long-term memory. Hearing the same story night after night can be very trying for parents, but the continued exposure to the same words, phrases, and ideas increases the toddler's ability to remember them.

Rhyme and Reason

Research shows that toddlers who hear the same nursery rhymes so often that they memorize them do better in school later on. The repetition is believed to help them to develop better memories — not just for the familiar rhymes, but also for remembering things in general. Break out the Mother Goose book and start reading! Nursery rhymes are invaluable teaching devices for several reasons:

Rhythms appeal to toddlers.

Hearing the same short poems over and over helps youngsters focus on individual words so they can eventually sort out their meanings.

The rhymes help them notice how small changes in sound create completely different meanings (like between “hot” and “pot” in “Pease Porridge Hot”).

Children who can recite nursery rhymes by heart do better in reading at school than toddlers with less exposure.

Nursery rhymes that involve pairing movements and words, such as in “This Little Piggy” and “Itsy Bitsy Spider” are called “finger play.”The movements help children decipher the meanings of the words while teaching them concepts, such as up and down (as when children move their fingers to show the spider going up the waterspout before swooping their arms down to show what happens when rain washes the spider out).

Here are a couple of classic finger-play poems your child will love:

This Little Piggy

This little piggy went to market (wiggle your child's big toe)

This little piggy stayed home (wiggle the second toe)

This little piggy ate roast beef (wiggle the third toe)

This little piggy ate none (wiggle the fourth toe)

This little piggy cried “wee, wee, wee” all the way home! (wiggle the little toe, then tickle up your child's leg)

Pat-a-Cake

Pat-a-cake, pat-a-cake, baker's man (holding your child on your lap, clap her hands together in the rhythm of the verse)

Bake me a cake as fast as you can

Pat it, and roll it … (roll her arms)

And mark it with a B (hold her hand and use it like a pen to draw a B on her tummy)

And throw it in the oven for Baby and me! (throw your arms open)

When you need someone else to take over, put on a top kiddie hit, like Time to Sing (Center for Creative Play) — it's got everything from “One, Two, Buckle My Shoe” to “The Wheels on the Bus.”

Memory Gaps

A toddler walks into the day care center he attends two days a week, takes one look at the teacher he's known for a year, and begins screaming as if he's never seen this stranger before. He hugs his blanket for comfort, then settles down as soon as he is handed a toy he recognizes or begins a familiar activity.

Because toddlers attending day care part-time don't experience the people and routines frequently enough to be able to retain many memories from week to week, they may find each new encounter almost as overwhelming as the first. Attending day care for a half day four times a week can be easier for them than attending for two full days.

The fragility of toddler memories has its benefits, too. If a child spits out a new food today, try it again in a week or two. There's a good chance she won't remember she didn't like it!

Programs like Head Start help children by providing lots of opportunity to interact with objects and people. The educational boost helps graduates to hold their own academically throughout their school career! Since 1965, Head Start has served millions of children, including those with mental retardation, physical handicaps, emotional disturbances, speech and language impairments, and learning disabilities. For information, see (202) 205-8572.

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