PDA or ADHD? Are We Looking at Behaviour When We Should Be Looking at Development?

There is a lot of discussion at the moment around Pathological Demand Avoidance, or PDA, particularly on social media.

Parents are describing children who experience extreme demand avoidance, distress, anger, loss of control and very strong reactions when something is expected of them. Those behaviours are real, and the distress experienced by children and their families can be very real too.

But I think there is another question we need to ask.

Does identifying the behaviour necessarily tell us what is causing it?

Or could similar behaviours sometimes be the end result of very different developmental pathways?

Where did PDA come from?

PDA originated from the clinical work of British developmental psychologist Elizabeth Newson, who began describing a group of children she believed showed a distinctive pattern of behaviour.

In 2003, Newson and colleagues published Pathological Demand Avoidance Syndrome: A Necessary Distinction Within the Pervasive Developmental Disorders.

Their clinical cohort included 150 children identified as having PDA through two specialist clinics in Nottingham over a period spanning 1975 to 2000.

The behaviours described included obsessive avoidance of everyday demands, using numerous strategies to avoid them, sudden mood changes, a strong need for control, difficulties with peers and extreme responses when demands increased.

Newson believed that the overall pattern was sufficiently different from classical autism and Asperger's syndrome to warrant consideration as a separate entity within what were then called pervasive developmental disorders.

It was an interesting clinical observation.

But there is an important distinction between identifying a behavioural pattern and identifying the mechanism causing that behaviour.

What didn't this research establish?

Newson's work did not establish a particular neurological mechanism responsible for PDA.

It didn't identify a specific “PDA brain”, neurological biomarker or genetic cause.

It didn't demonstrate that a demand automatically causes a particular subconscious nervous-system response.

It didn't establish that demand avoidance is always caused by anxiety.

And importantly for my own work, it didn't prospectively follow children from infancy to establish how these behaviours developed.

That doesn't invalidate the behaviours Newson observed.

It simply leaves us with another question:

How did the child get there?

What happened before the behaviour?

By the time we are looking at a child at five, eight or ten, that child has already experienced years of development.

They have experienced relationships, expectations, nursery or school, success and failure, correction, sensory experiences and learning.

They are also developing something incredibly important: their sense of themselves.

What do they believe they're good at?

What do they expect will happen when somebody asks them to do something difficult?

How do they interpret another person's instructions?

What have previous experiences taught them?

If we see extreme demand avoidance later, therefore, should we automatically assume that one PDA mechanism has always been there?

Or should we also ask:

How did this behaviour develop?

Two children can both say “NO” for completely different reasons

Imagine two children are asked to stop playing and put their shoes on.

Both shout:

“NO!”

From the outside, the behaviour looks remarkably similar.

But one child might be struggling to shift their attention away from what they're doing.

Another might be emotionally overloaded.

Another might experience a strong loss of agency when somebody else determines what they must do.

Another might be uncertain about what happens next.

Another may remember previous experiences of struggling with the same task and already expect failure.

Another may be anticipating an uncomfortable sensory environment.

And several of those processes may be happening together.

This is why I think one sentence is particularly important:

A demand is not one neurological event.

Receiving and responding to a demand can involve attention, action selection, motivation and reward, prediction, sensory processing, emotional responding, communication, previous learning and our sense of agency.

The behaviour we eventually see is the end of that process.

Where does ADHD come into this?

ADHD development doesn't suddenly begin when executive-function difficulties become obvious at school.

Although ADHD is often discussed through delayed maturation of the prefrontal cortex and executive functions, research has also identified developmental differences earlier in childhood involving interacting cortical and subcortical systems.

One example that particularly interests me is the caudate, part of the striatum within the basal ganglia.

Research involving very young children with ADHD has reported measurable differences in the caudate. These circuits are involved in processes including action selection, motivation, reward learning and learning from the consequences of our actions.

Why might that be relevant to demands?

Because responding to a demand can require a child to stop an action they have chosen, shift towards somebody else's requested action, decide whether to act, anticipate what will happen and use previous experience to guide their response.

That does not mean that caudate differences cause PDA.

It raises a different question.

Could developmental differences within systems involved in action, motivation, learning and agency contribute to the way some children experience and respond to demands?

A different developmental hypothesis

My hypothesis is that, for at least some children, behaviours later described as pathological demand avoidance may emerge through different combinations of neurodevelopmental differences interacting with experience and environment during early development.

I am not claiming that this has been proven.

I think it is a question worth investigating.

Because if several developmental pathways can lead to similar outward behaviour, then identifying the behaviour doesn't necessarily identify the mechanism underneath it.

Does every strong response to a demand mean anxiety?

This is another question that interests me personally.

I have ADHD myself and have neurodivergent children. I recognise some of the experiences described within demand avoidance.

But they don't always feel like fear or anxiety.

Sometimes an interaction can feel like somebody is positioning themselves above you.

It can feel like a loss of agency. It can produce anger, defensiveness or an overwhelming urge to regain control.

That is my experience. It cannot tell me what another person — particularly a young child — is experiencing.

But it does make me question whether we should automatically interpret every strong response to a demand as anxiety or nervous-system threat.

We need to ask questions about the explanations too

If we are told that demands automatically produce a subconscious nervous-system danger response, what evidence establishes that particular mechanism?

If a child appears to need to feel equal to or above another person, what are we actually seeing?

Anxiety?

Agency?

Autonomy?

An interpretation of status?

Previous learning?

Or something else?

And if removing a demand reduces a child's distress, that tells us something useful — but does it necessarily tell us why the demand caused the distress?

Those are different questions.

Similarly, an intervention that reduces conflict today may be extremely valuable. But I think we should also ask whether it helps the child develop the capacity they will need tomorrow.

Supporting a child doesn't mean forcing them through distress

This is an important distinction.

I'm not suggesting that distressed children should simply be pushed harder or forced to comply.

I am asking:

Why is this difficult for this individual child, and what can we support?

Sometimes the environment absolutely needs adapting.

Sometimes a child needs more predictability, communication, sensory support or co-regulation.

But I also think there is a place for manageable, supported experiences through which children gradually discover:

I can cope with disappointment.

I can wait.

Plans can change and I can still be okay.

Somebody can disagree with me without diminishing me.

I don't always have control, but I haven't lost my agency.

Supporting autonomy shouldn't have to mean ensuring that a child always remains in control.

Ultimately, I want children to develop a sense of agency even when they cannot control the situation.

Why I believe the early years matter

This is why my work focuses so heavily on children under five.

Early childhood is a period of extraordinarily rapid development.

Instead of waiting until behaviour has become established and asking only:

“What does my child have?”

I want us to begin asking much earlier:

What is developing?

What feels difficult?

Why might it feel difficult?

What is my child learning from this experience?

And:

What can we help them understand about themselves?

Young children can gradually learn emotional meaning, flexibility, perspective, communication and how to recognise what is happening inside themselves.

They can experience manageable discomfort while supported by an adult who helps them make sense of it.

The aim isn't to eliminate every uncomfortable feeling.

It is to help children gradually develop the knowledge to recognise those feelings and the capacity to decide what to do with them.

Because eventually that young child becomes an adult.

I want them to be able to think:

“This feels horrible, but I recognise it.”

“I don't know yet what that person meant.”

“I don't have to react immediately.”

“Someone else's boundary doesn't determine my worth.”

“I still have agency even when I don't get my way.”

So, is PDA real?

The behaviours certainly are.

The distress certainly can be.

But I think we need to be careful about assuming that one label automatically tells us the mechanism underneath those behaviours.

The developing brain is far more complicated than:

one label → one mechanism → one response.

So perhaps the question isn't only:

PDA or ADHD?

Perhaps we should also be asking:

What developmental path brought this individual child here?

And maybe that question gives us somewhere very different to begin.