UK parents urged to curb fast-paced screen content for small children – neuroscientist who advised government explains why

The UK Department for Education has just released guidance for parents on early years screen use, which I advised on as an expert. It includes recommended limits on the time children spend on screens. It also advises avoiding fast-paced content for younger children.

Recent research from the UK Department for Education suggests that over half of two-year-olds now spend over two hours a day watching screens. For the top 20%, that figure approaches five hours daily – more than a third of their waking life.

These changes have occurred rapidly, particularly since the introduction of smartphones. In 2009, children aged five to 15 spent around nine hours a week – about 1.3 hours a day – watching screens.

But the nature of what children watch has shifted just as dramatically as the amount of time they spend doing so.

Fifteen years ago, close to half of UK preschoolers tuned into CBeebies – BBC content aimed at children aged six and under – each week. Today, children’s engagement with content produced by TV companies is almost 75% lower.

Over the same period, short-form, on-demand video has expanded rapidly. Now, more than 90% of three- to five-year-olds use video-sharing platforms such as YouTube.

To illustrate what this means in practice, we can compare a 25-minute episode of the CBeebies show In the Night Garden from 2006 with a 25-minute slice of typical viewing from a four-year-old watching YouTube Kids (the latter taken from a recent US study).

The CBeebies episode followed a single narrative thread, with a stable cast of eight characters. The YouTube sample is made up of ten separate clips within the same timeframe, featuring 37 speaking characters. The editing tempo shifted from one cut every 16.7 seconds in the CBeebies episode to one cut every 1.5 seconds. There were sharp increases in visual stimulation (changes in light and colour) and auditory stimulation (shifts in pitch and volume).

Comprehension and attention

From a neuroscience perspective, we think this transformation has taken place because there are two ways in which content can hold a young child’s attention.

One route works through comprehension. Slow pacing, clear speech, exaggerated expressions and simple narrative structure allow children to follow what is happening. Comprehension drives attention.

The second route operates through attention capture. Rapid movement, abrupt edits and dynamic sound capture attention automatically. Even if we are trying not to pay attention to something, movement makes it hard to ignore. We think that we developed like this because, historically, motion signalled threat or opportunity. That reflex remains. Attention capture is immediate, involuntary and does not depend on comprehension.

Much contemporary digital content leans heavily on this second mechanism. It is instantaneous, and it works on everybody.

This shift to fast-paced content may, though, also have a role to play in the links between early screen use and later emotional and behavioural dysregulation: difficulties managing emotions and behaviour.

The reason is that young brains run at a slower tempo than adult brains. When environments are fast and unpredictable, the nervous system shifts into a heightened alert state to enable rapid detection of change. Brainstem systems involved in arousal become more active. The sympathetic nervous system – the same system engaged during fight-or-flight responses – becomes involved. In the short term, this may help explain why many children appear irritable or dysregulated when screens are switched off.

Finding patterns

Over longer periods, repeated exposure to highly stimulating, unpredictable content may contribute to broader patterns of behavioural and emotional dysregulation linked to screen use. A growing body of correlational research links high levels of early screen exposure with later difficulties in regulation and increased rates of anxiety. Correlational research shows that two things often occur together or in the same person – such as screen time and anxiety – but don’t prove that one caused the other.

Both behavioural dysregulation in childhood and anxiety in adulthood are associated with heightened brainstem and sympathetic activity – systems that are engaged by fast-paced screen content.

Much of the evidence remains correlational, making it hard to infer causation. However, some animal studies have experimentally exposed animals to doses of simulated screen time, showing that screen exposure causally affects arousal in ways that are consistent with the correlational findings.

Together, the pieces of evidence fit together in a way that is increasingly difficult to ignore – particularly against the backdrop of rising mental health difficulties in young children.

The government guidance recognises this faster-paced content – which is why the advice is to avoid it for young children. But history suggests that advisory-only approaches rarely shift behaviour at scale. If aspects of the current digital environment are indeed contributing to regulatory and mental health challenges, policy attention may need to move further upstream.

That would mean reconsidering the responsibilities of content producers and platform designers, not only parents. How exactly to do this, though, is fraught with difficulty – particularly at a time when the science itself is struggling to keep up with the pace of change.

Sam Wass receives funding from Leverhulme Trust RPG-2025-114