For most of the first year of life, “out of sight, out of mind” is a literal truth. If an object or person is hidden or leaves their field of vision, your baby can’t understand that it still exists. Starting around 6 to 9 months, though, your baby develops an important cognitive skill: object permanence, an essential building block for working memory, language development, and emotional attachment. And playing peekaboo just got a lot more fun, too 😉

In this article:

• What is object permanence?
• When does object permanence develop in babies?
• Why is object permanence important? 
• Object permanence and separation anxiety
• Tips for coping with separation anxiety
• How can I help my baby with object permanence?
• Games that teach object permanence
• Toys that teach object permanence
• Developmental concerns with object permanence

What is object permanence?

Object permanence is the concept that objects or people exist even if they’re out of sight. When your baby goes to look for the rattle you hid under a blanket, or looks for you when you leave the room, that’s object permanence at work.

Very young babies have not yet developed this concept. If you hide a toy from your 3-month-old, for example, there’s a good chance they won’t go looking for it because for them, the object no longer exists. When babies start to remember objects from one appearance to the next, they learn that just because something can’t be seen at the moment, that doesn’t mean it’s gone forever. 

When does object permanence develop in babies?

Babies generally develop a concept of object permanence around 6 to 9 months of age. You may begin to notice it emerging naturally as part of your daily routine of feedings, care, and play. If the family pet trots off, your baby may want to see where they went. If a plaything rolls under a chair or into a basket, they will likely try to go find it. If food falls off their high chair, they may start looking to see where it fell (particularly if that food is purposely dropped, after your baby develops the skill of voluntary release around 9 months). These are all clear signs that the concept of object permanence is taking hold in your baby’s brain.

Why is object permanence important? 

Object permanence is important in your baby’s cognitive development because it shows their growth in working memory as well as their progression in symbolic understanding. Here’s what those terms mean, and why they matter:

Working memory is what helps us keep information in mind while we’re working on a cognitive task. As your baby develops the concept of object permanence, they’ll begin to store a mental picture of a plaything, object, or person in their working memory while they look for it. Working memory is what allows them to remember the object or person still exists even when they’re not physically present.

Symbolic understanding helps your baby know that symbols or mental representations can stand for real-life objects. This knowledge is ultimately one of the factors that helps your baby learn language. Language is a symbolic concept—words are the symbols for tangible objects. When your baby develops object permanence, they are able to symbolically hold the image of an object or person in their mind. 

Object permanence and separation anxiety

One challenging aspect of your baby developing object permanence is that it sometimes comes with an increase in separation anxiety. Separation anxiety emerges for many babies around 6 to 10 months of age—right as they’re developing the concept of object permanence—and it may look like a dramatic change from their previous behavior. Your baby may cry when you leave, cling to you, or be reluctant to stay with another caregiver when they know you’re leaving. 

What’s going on? Your baby’s working memory has made a big leap. They can hold a picture of you in their mind even when you aren’t physically present, which means they may feel anxious when you have to leave to go to work, or even just leave the room to get a drink of water. Because they don’t understand time yet, they have no sense of when you’ll return, which can be scary for them. When you “disappear,” your baby knows you still exist—but doesn’t know when you’ll be back.

While this may sound a little bit sad or stressful for your baby, the good news is that object permanence plays a key role in your baby’s emotional development. Over time and with practice, your baby will begin to understand that you do come back, even if you are separated for a while. In this way, they learn that they can rely on you for support and care ❤️

Tips for coping with separation anxiety

Practice “away” and “back.” A helpful habit to get into when your baby is in the thick of the separation anxiety phase: make your own comings and goings extra clear. Say, “Mommy is going to the bathroom and coming back,” and when you return, say, “Mommy came back!” If you need to step into another room, you can use your voice to let your baby know you’re close by even when you can’t be seen: “I’m in the kitchen getting a glass of water. I’m coming back soon.” Through lots of practice and repetition with separations, your baby learns that their grown ups will reliably return.

Validate your baby’s emotions. If you need to walk away for any reason, let your baby know what’s happening, and validate their feelings if they get upset. You can say something like, “I’m going to get a drink of water and then come back! I see that you’re sad that I’m walking away. I am going to get water and be right back.” Showing that you understand their emotions, along with demonstrating that you always come back, helps your baby understand that you’re a reliable source of comfort. 

RELATED: How to ease your baby’s separation anxiety

Have special goodbye rituals. You may want to set up a simple, quick goodbye ritual that you do each time you leave, like a kiss, a hug, or a special toy that only comes out when you have to separate. While it may seem easier to “sneak out” when your baby seems distracted or otherwise occupied, your baby is likely to be even more upset when they discover your absence. Try to keep transitions brief, clear, and positive: Say goodbye and tell your baby what’s happening. “Mommy is going to work. I’ll see you at bath time. Daddy will take care of you. I love you!”  Give your baby your full attention, be cheerful and upbeat, and try not to linger—it just prolongs your departure. 

Play games to practice. Games like peekaboo (both face-to-face and in a mirror) can help your baby grasp that you always return even if you’re gone for a while. Practice saying hello and goodbye whenever possible—you can do this during daily routines like changing a diaper, for example, saying “Goodbye!” to a dirty diaper and “Hello!” to a clean one. 

How can I help my baby with object permanence?

Your baby develops object permanence on their own unique timeline, but there are activities and games that may help the process along. Through play, you can help your baby understand that objects still exist even when they are hidden.

Games that teach object permanence

Hiding toys in a bag or Treasure Basket, or containing objects within other objects (like hiding a ball in the Sliding Top Box) can help make the concept of object permanence more tangible to your baby.

Starting around 6 months of age, your baby may begin to love the game peekaboo. With the concept of object permanence emerging, this game takes on a whole new meaning for your baby. Since they’re beginning to understand that you’re still present even when your face is hidden, they may giggle with delight when you pop out from behind your hands or a blanket.

Momentary separations (like in peekaboo) followed by happy reunions also help build trust and may help reduce separation anxiety ❤️

• Sit within arm’s reach of your baby.
• Cover your face with a Magic Tissue, cloth napkin, or scarf.
• Ask, “Where’s Mommy?” or “Where’s Daddy?” to help them build an association between your name and face.
• Pause for a moment before revealing your face with an animated, “Here I am!”
• Give your baby a turn. Hide their face behind the tissue or napkin and say, “Where’s baby (or your child’s name)?” Remove the tissue and say, ”There you are!”
• Continue to alternate to help your baby learn the important social skill of taking turns. 

Toys that teach object permanence

Toys and playthings can be wonderful tools to help your baby learn about object permanence. Although most object permanence toys seem simple to adults, you might be surprised at how engaging they are for your baby. 

The Ball Drop Box is a perfect example of simple plaything that engages your baby’s curiosity and illustrates the concept of object permanence. Your baby pushes the ball through the hole and it briefly disappears… only to reappear a second later on the platform. Your baby begins to see how an object is still there even if it can’t be seen momentarily.  

Explore The Ball Drop Box and more toys that teach object permanence

The Inspector Play Kit

The Inspector Play Kit exposes your 7 – 8 month old to the world with detailed sensory experiences by exploring texture, practicing nesting and stacking, and learning about object permanence.

Learn more

A slightly more advanced version of the Ball Drop Box is the Sliding Top Box. With this plaything, your baby has to search a little harder to find the hidden ball. The ball drops in the hole and then disappears behind a sliding door. Your baby has to use their problem solving skills to discover how to slide the top to uncover the ball. Peekaboo, they see the ball!

RELATED: How the Sliding Top Box helps build your baby’s working memory

Developmental concerns with object permanence

Each child develops along their own developmental trajectory, and age ranges for milestones such as learning object permanence are based on averages. If your child reaches 12 months of age and you’re concerned that they may be lacking object permanence understanding, discuss your concerns with your pediatrician. 

It can be helpful to know that different aspects of your child’s development are linked. Some evidence suggests that the age at which your child learns to sit up may influence the development of object permanence. Once children can sit, they can use their hands to investigate objects more closely. Additionally, sitting up allows children to view objects from varied angles which may help with understanding that objects still exist even when they’re hidden. You may see a noticeable leap in your child’s interest in peekaboo games and toys after they’re able to sit up independently or with support.