ADHD Myth Busted: Why ‘Out of Sight, Out of Mind’ Isn’t Object Permanence

Many people with ADHD hear the phrase “out of sight, out of mind” and assume it means they never developed object permanence. But that’s a myth. Object permanence is a cognitive skill that develops in infancy, allowing you to understand that something still exists even when you can’t see it. In fact, according to a review, infants begin showing signs of object permanence months before their first birthday.

So why do adults with ADHD sometimes forget about things once they’re hidden away? The answer lies in differences in attention and working memory, not in a lack of basic cognitive development. While object permanence explains how we know an object continues to exist, ADHD challenges affect how well we keep track of that object in daily life.

Piaget’s Original Theory

Swiss psychologist Jean Piaget first described object permanence as a key milestone in the sensorimotor stage of development. In his model, this stage covers birth to about two years of age and is divided into six substages, each showing a gradual shift from reflexive actions to intentional problem-solving. According to research, Piaget believed that infants only grasped object permanence around 8 to 9 months old, when they could search for a hidden object on purpose.

Piaget’s experiments often involved hiding a toy under a blanket and watching whether the infant tried to find it. If the child didn’t search, he concluded they didn’t yet understand the toy still existed. These observations led him to view object permanence as something that developed slowly through hands-on interaction and repeated experiences with the environment.

Challenges to Piaget’s Timeline

Later research questioned Piaget’s idea that object permanence appears only around 8 or 9 months. Using more sensitive testing methods, scientists discovered signs of this ability much earlier. In a published article, Renée Baillargeon used the violation-of-expectation method, where infants saw events that were either possible or impossible based on the laws of physics. Even at 3 1⁄2 months, babies looked longer at “impossible” events, suggesting they already understood objects still exist when out of sight.

Key factors that challenged Piaget’s original timeline include:

• Earlier cognitive recognition: Infants as young as 3½ months show signs of understanding object permanence.
• Method differences: Newer tests use looking-time measures instead of relying on search behaviors.
• Motor skill limitations: Babies may understand an object still exists but lack the coordination to find it.
• Separation of perception from action: Understanding can develop before the ability to physically respond.

These findings suggest that cognitive milestones may emerge sooner than Piaget believed, shifting how psychologists view early development.

Why the Myth Persists in ADHD

The idea that people with ADHD lack object permanence likely comes from how ADHD affects attention and working memory, not from a missing early developmental skill. In a review, experts explain that working memory is crucial for keeping information active in the mind. When this system struggles, it’s easier to forget about items, tasks, or ideas once they’re no longer visible.

Common factors that keep this myth alive include:

• Working memory challenges: Difficulty holding information in mind without visual cues.
• Attention shifts: Distraction by new stimuli causes older tasks or items to fade from focus.
• Mental fatigue: Reduced cognitive energy makes it harder to recall out-of-sight information.
• Behavioral similarity: Forgetfulness in ADHD can look like the pre-object permanence stage in infants.

These patterns may seem like a lack of object permanence, but research shows ADHD-related forgetfulness comes from how the brain processes and retrieves information—not from failing to develop a basic cognitive skill.

Separating ADHD and Object Permanence

ADHD and object permanence involve different cognitive processes. Object permanence is a developmental skill formed in infancy, while ADHD is a lifelong neurodevelopmental condition that affects focus, organization, and working memory. According to research, object permanence is well established long before ADHD symptoms appear.

Key differences include:

• Timing of development: Object permanence develops in the first year of life; ADHD symptoms often emerge later.
• Type of skill: Object permanence relates to understanding the continued existence of objects; ADHD affects attention regulation and mental organization.
• Cause of forgetfulness: ADHD forgetfulness comes from working memory and attention issues, not a lack of object permanence.
• Impact on daily life: Object permanence is stable once formed; ADHD challenges can fluctuate depending on mental energy, environment, and distractions.

Understanding these distinctions prevents the false belief that ADHD is linked to a missing developmental milestone and promotes more accurate support strategies.

The Role of Working Memory in ADHD

Working memory acts like a mental workspace, holding and processing information for short periods so you can complete tasks. In ADHD, this system often works less efficiently, making it harder to keep track of what needs to be done when cues disappear from view. According to findings, working memory deficits are a core feature of ADHD and directly influence task completion, planning, and follow-through.

A reduced working memory capacity can mean:

• Forgetting to return to a task once interrupted.
• Losing track of what you intended to do without a visual reminder.
• Struggling to recall details of an ongoing project.
• Depending heavily on external cues, such as notes or alarms, to maintain focus.

These difficulties are often mistaken for not understanding that something still exists out of sight. In reality, the challenge is keeping that information mentally accessible, not believing it has disappeared.

Practical Strategies for ADHD Forgetfulness

Managing ADHD-related forgetfulness often means building consistent, visible systems to keep important tasks and items in mind. Instead of relying solely on memory, you can use tools and habits that make information harder to lose. Experts suggest that external support can help bypass working memory challenges and maintain momentum on daily responsibilities.

Helpful strategies include:

• Using visual reminders like sticky notes or whiteboards in frequently visited spaces.
• Setting digital alerts for deadlines, appointments, and recurring tasks.
• Keeping essential items in a consistent, visible location.
• Breaking large projects into smaller, trackable steps.
• Pairing routines with specific cues, such as taking medication when making morning coffee.

These approaches work because they reduce reliance on internal memory and create a steady flow of prompts to guide attention back to what matters.

Wrap Up

Understanding the truth about ADHD and object permanence helps clear up a common misunderstanding. People with ADHD don’t lack this early developmental skill—they’ve had it since infancy. The real challenge comes from differences in working memory and attention, which make it harder to keep track of things once they’re out of sight.

By recognizing this distinction, you can focus on practical strategies that work for ADHD brains instead of relying on outdated myths. What changes could you make today to help your environment work with your mind, not against it?