Cognitive abilities, such as attention, problem-solving, and self-control develop rapidly during the preschool years. These are the building blocks for how children learn, interact with others, and understand the world around them. One of the most powerful tools to support your child’s cognitive development is sleep.
Sleep is not just about rest. For children, it is a time when the brain grows, reorganises, and strengthens the pathways that support thinking and learning. During sleep, the brain consolidates what your child has learned during the day. Their subjective experiences are processed and transferred to long-term memory and knowledge.
In preschoolers, this might mean remembering a new word, recalling a social interaction, or learning to follow a new routine. Sleep also supports the development of executive functions: the skills children use to regulate their behaviour, focus their attention, and switch flexibly between tasks.
Preschool-aged children experience a relatively high amount of deep, “slow-wave”, sleep – the stage of sleep when the brain activity slows down the most. In this phase, the brain sorts through the day’s experiences, stores new knowledge, strengthens important pathways, and clears out unnecessary information. This is especially important for building and refining neural connections in the prefrontal cortex, which is part of the brain involved in reasoning, decision-making, and self-control, situated right behind the forehead. Thus, sleep is not a passive state, but an essential part of how young children develop the ability to think, feel, and act purposefully.
Preschoolers typically need between ten and fourteen hours of sleep over a 24-hour period. This includes both nighttime sleep and, for younger children, an afternoon nap. As children grow older, many begin to phase out daytime sleep. However, even if your child no longer naps, a quiet rest period during the day can still help support emotional balance and mental clarity.
When preschoolers do not get the sleep they need, the effects often appear quickly and most noticeably in how they think, learn, and manage emotions. A tired child may struggle to focus on a task, remember instructions, or solve problems that usually come easily. They may become more irritable, impulsive, or emotionally reactive. These behaviours are common in early childhood, but they tend to intensify when sleep is disrupted or insufficient.
Sleep deprivation in children is associated with reduced attention spans, and difficulty with memory retention and processing speed. Executive functions, including self-regulation, planning, and flexible thinking, are particularly vulnerable to poor sleep. Over time, sleep difficulties can affect school readiness, social interactions, and overall well-being.
Consistency is key. Maintaining consistent sleep and wake times, even on weekend, helps stabilise your child’s internal rhythm and supports better quality sleep. While each child’s needs may differ, significant fluctuations in sleep patterns or duration are likely to affect cognitive functioning throughout the day.
Establishing healthy sleep habits can make a meaningful difference in your child’s cognitive development. Here are several evidence-based approaches that can help:
Create a predictable bedtime routine: A consistent evening routine (e.g., brushing teeth, putting on pyjamas, and reading a story) helps signal to the body that it is time for sleep. Enhance your routine with screen-free, narrative-based tools like the Ecole des Loisirs – Lampe à Histoires Minusculette. These gentle story projectors turn bedtime into a calm and cosy moment for listening and imagination.
Limit screen time before bed: The artificial light from televisions, tablets, and phones can delay the release of melatonin, the hormone that helps us feel sleepy. Aim to turn off screens at least one hour before bedtime and opt for alternative ways to wind down. The game Au Lit ouistitis!, recommended for children aged 3 and up, encourages cooperation and positive associations with bedtime. The goal is to help four little monkeys fall asleep through calmness and affection – but be careful not to wake them up!
Maintain a stable sleep schedule: Keeping bedtime and wake-up times consistent – even on weekends – helps regulate your child’s internal rhythm and improves both the quality and duration of sleep.
Support daytime rest: Even if your child no longer naps regularly, offering a short period of quiet time in the early afternoon can still help their brain and body recharge. Mon petit morphée, for example, offers soothing stories, nature sounds, and gentle music that support emotional regulation and create a peaceful environment for reflection and rest.
