What You Need to Know About Object Permanence

You step out of the room for just a second, and suddenly, your baby bursts into tears. Just yesterday, they were happily playing peekaboo, giggling every time you covered your face. But now? The moment you disappear from sight, they panic. 

This sudden change can feel confusing, but it’s actually a big milestone in your baby’s development. They’re starting to understand something new—when they can’t see you, you still exist. This concept is called object permanence, and while it’s an exciting step in their growth, it can also bring challenges, especially at bedtime. 

As a Certified Sleep Sense Consultant at Lullabub Sleepers, I’ve worked with many families in Singapore going through this phase. Let’s talk about how object permanence affects sleep training a baby and what you can do to help your little one feel secure, even when you’re not in the room. 

What Is Object Permanence? 

Object permanence is a concept developed by Swiss psychologist Jean Piaget, referring to a baby’s realization that objects and people exist even when out of sight. This typically starts to develop around 4–7 months and becomes more evident by 8–12 months. 

Before object permanence, your baby believes that if they can’t see something, it doesn’t exist. That’s why peekaboo is so entertaining! But once they start grasping the idea, separation anxiety can emerge—especially at bedtime. 

How Object Permanence Affects Sleep Training a Baby 

Once babies realize that parents still exist even when they leave the room, they may start resisting sleep, crying when put down, or waking up frequently to check if you’re still there. This is why many parents notice sleep regressions around the 8–10-month mark. 

Common sleep challenges linked to object permanence:  ✅ Increased crying at bedtime  ✅ More night wakings  ✅ Clinginess during naps  ✅ Difficulty settling without a caregiver present 

But don’t worry—this is completely normal! It just means your baby is growing and developing. 

Helping Your Baby Through Object Permanence & Sleep Training 

1. Practice Short Separations 

Start with small moments of separation during the day, such as stepping into another room while talking to your baby. This helps them gradually adjust to the idea that you always come back. 

2. Play Peekaboo & Hide-and-Seek 

Simple games like peekaboo help reinforce object permanence in a fun and reassuring way. You can also hide a toy under a blanket and encourage your baby to find it. 

3. Create a Strong Bedtime Routine 

A predictable bedtime routine helps your baby feel safe. Try a warm bath, gentle massage, lullabies, and dim lighting to signal that it’s time for sleep. 

4. Introduce a Comfort Object 

A lovey or security blanket can provide comfort when you’re not in the room. Make sure it’s safe and age-appropriate. 

5. Practice Gentle Sleep Training Methods 

If your baby struggles with night wakings, gentle sleep training methods like the Ferber method, chair method, or gradual withdrawal can help them learn to self-soothe. 

Object Permanence & Separation Anxiety: What’s Normal? 

It's completely normal for babies to cry when you leave. Separation anxiety peaks between 9–12 months but can continue into toddlerhood. Reassuring them with consistent routines, short separations, and a calm response will help ease this transition. 

Final Thoughts 

Object permanence is a big milestone in your baby’s cognitive growth. While it may bring new sleep challenges, with the right approach, your baby can learn to self-soothe and sleep peacefully. Remember, every baby develops at their own pace, and patience is key. 

If you're struggling with sleep training a baby, know that help is available. I’m here to support you through every step—because a well-rested baby means a well-rested family. 

Need personalized sleep support? Check out my services and let's help your little one sleep better! 

FAQs 

How does object permanence affect sleep? 

Once babies develop object permanence, they understand that you still exist even when they can’t see you. This can lead to sleep disruptions because they may cry or protest when you leave the room, struggling with separation anxiety and making sleep training a baby more challenging. 

What is the 5-10-15 rule for baby sleep? 

The 5-10-15 method is a sleep training technique where parents wait 5 minutes before comforting a crying baby, then increase the waiting time to 10 minutes, then 15 minutes, gradually helping the baby learn to self-soothe. 

What is the 5-3-3 rule for babies? 

The 5-3-3 rule is a feeding schedule for newborns, where you feed every 5 hours at night, then every 3 hours during the day, and again every 3 hours before bedtime to help establish a routine. 

What is the 80/20 rule for sleep for babies?

The 80/20 rule suggests that if your baby sleeps well 80% of the time, occasional disruptions (like teething or travel) won’t derail their sleep habits, making sleep training a baby more flexible and realistic. 

What happens if you lack object permanence?

Without object permanence, a baby or person may struggle to understand that things or people continue to exist when out of sight, which can cause distress when separated from caregivers. 

How long is too long for the cry-it-out method? 

Experts recommend not letting babies cry for longer than 30-60 minutes at a time, as prolonged distress can lead to increased cortisol levels and sleep associations that may not be beneficial. 

Who struggles with object permanence? 

Infants naturally struggle with object permanence until about 8 months old. Some individuals with ADHD or certain cognitive conditions may also have difficulty maintaining awareness of things when they are out of sight. 

What is the 8-month crisis? 

The 8-month sleep regression, also known as the 8-month crisis, happens when babies develop object permanence and separation anxiety, causing them to wake frequently and resist being left alone. 

Why do people with ADHD struggle with object permanence? 

People with ADHD often experience "object permanence challenges," meaning they may forget about tasks, objects, or people when they are out of sight, leading to difficulties in organization and memory. 

Why is my 7-month-old waking up every hour? 

At 7 months, sleep disruptions can be caused by teething, growth spurts, or separation anxiety due to developing object permanence. Sleep regressions and changing sleep cycles can also be factors. 

What is the major implication of object permanence? 

The biggest impact of object permanence is that babies begin to understand that people and things continue to exist even when unseen, which can lead to separation anxiety but also supports cognitive growth. 

Why is my 10-month-old awake for hours at night? 

A 10-month-old may wake for long periods due to teething, a sleep regression, hunger, or increased mobility as they practice new skills. Object permanence can also play a role, as they may seek reassurance from caregivers.