Most adults cannot remember anything before their third birthday. That's because of childhood amnesia. But experts explain why you should still focus on making memories with your young kids, even if you'll be the only one who remembers them.

Have you ever wondered why your child won't remember taking his first steps or celebrating his second birthday? If you try to recall your own experiences of being a preschooler, you can probably only conjure up hazy images. The reason for this is a phenomenon known as childhood or infantile amnesia—the natural and gradual loss of memories from the first few years of life.

Disney's animation Inside Out shows childhood amnesia in action when Bing Bong, Riley's previously much-loved imaginary friend, ends up being forgotten in the memory dump of her mind. Bing Bong's fate, while heartbreaking to watch, is actually an inevitable part of Riley growing up. Psychologists believe childhood amnesia is a normal part of brain development and that memories which are not repeatedly retold and strengthened become lost over time.

When we talk about memory, we are usually referring to the ability to recall life experiences. Known as episodic memories, these involve the hippocampus, a part of the brain found in the temporal lobe, which is not fully developed at birth. "The hippocampus should be ready at about the age of 4 and this is usually when children start remembering things consistently," says Rachael Elward, Ph.D., an expert in the cognitive neuroscience of memory. "The older a child gets, the more stable their memories become."

Another reason for childhood amnesia? Sally Goddard Blythe, the director of the Institute for Neuro-Physiological Psychology (INPP) in the United Kingdom and the author of eight books on child development, says we don't have the ability to talk about things which happened to us before we are fluent in a language. Verbal language, she says, doesn't reach a stage of sufficient fluency until about 3.

But this doesn't mean that young children can't remember things that have happened. "Children do have these kinds of memories but they disappear really quickly," says Dr. Elward.

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When Do We Start Remembering Our Memories

For most adults, their earliest episodic memory will be from the age of 3 onwards with few remembering anything before that. Yet academics believe that memories of early childhood start to be lost rapidly from around the age of 7.

In a study into childhood memory by Patricia Bauer and Marina Larkina, 3-year-olds were asked to talk to their mothers about six past events from their lives. They were then asked to remember these events when they were older. The researchers found that between the ages of 5 and 7, the children remembered more than 60 percent of the events, but by the ages of 8 and 9, this had fallen to less than 40 percent.

But these memories aren't always gone for good. "Conscious memory is thought to develop from about 3, but before that, there is sensory-emotional experience which may be revived in later life when similar events or sensory triggers are present," says Blythe. "A pleasant example of sensory memory may be a particular smell (the most evocative of the senses), which, many years later, conjures an image or even a sense of presence of our mother."

Blythe suggests helping your children access their early years by talking to them about things that happened and showing them family photographs. "It is lovely if parents make an album or memory book of their children's early life, so that later on they can revisit with language and conscious memory," says Blythe.

Why You Should Still Make Memories With Your Young Kids

Infantile amnesia isn't a reason to avoid an elaborate first birthday party or a trip to the movies with your 2-year-old. It is still really important to do things with your young children even though they won't remember them when they are older.

"Sharing experiences is important for bonding and helps your child learn about the world around them," says Dr. Elward. "While they might not remember a specific visit to the zoo, they will remember things like what a zoo is and the names of the animals."