🔬 PERCY'S PANORAMA 🔬 A Special Investigation by Percy

WHY YOUR ADOLESCENT DOG IS NOT BROKEN — AND WHAT IS ACTUALLY HAPPENING INSIDE THEIR HEAD

Let me address something immediately: I did not go through adolescence. I emerged from puppyhood essentially fully-formed — intellectually sophisticated, emotionally regulated, and already displaying the kind of behavioural elegance that others spend years attempting to achieve. I realise this may be difficult for some of you to accept, but I have always been exceptional, and this is simply the truth of the matter.

I mention this only to establish my credentials as a neutral observer of the adolescent phenomenon. I study it from the outside, as a scholar might study a storm from a comfortable armchair — fascinated, analytical, and entirely unaffected.

We will return to this point at the end.

PART ONE: THE CONSTRUCTION SITE (Or, What Puppyhood Actually Builds)

Before we can understand adolescence, we must understand what precedes it.

The puppy brain is a construction site of spectacular proportions. In the earliest weeks and months of life, the brain produces a vast excess of neural connections — synapses — in what neuroscientists rather grandly call synaptogenesis. The brain essentially overbuilds. It generates far more connections than it will ultimately need, covering virtually every possible behavioural and experiential eventuality, hedging its bets against an unknown future.

What follows is a process of active editing.

The brain trims unused connections to work better — a "use it or lose it" process that supports learning, memory, and development. The connections that fire regularly — those attached to repeated experiences, rehearsed behaviours, and environmental patterns — are preserved and strengthened. Those that go unused are quietly eliminated. Cleveland Clinic

Consider what this means in practical terms. During puppyhood, your dog is doing something extraordinary. Every training session, every socialisation experience, every routine walk, every interaction with you — is contributing to a vast neural editing process. You are not just teaching a puppy to sit. You are helping determine which connections survive.

My father, Oliver — who is also, I should note, my editor, and who was running the session I am about to describe — offered an analogy that I found, with some reluctance, rather good.

During puppyhood, he suggested, you are cutting out all the pieces of a puzzle and beginning to assemble the picture. You are establishing the edges, finding the obvious clusters, starting to see what the finished image might become.

Then adolescence arrives.

And someone walks past and knocks the puzzle off the table.

PART TWO: THE RENOVATION (Or, Why The Pieces Are Still There)

This is the most important thing I can tell you about adolescent regression, and I want you to read it carefully before we proceed.

Adolescence is not a breakdown.

It is a renovation.

The brain undergoes a remodelling process that starts often just before the teenage years begin and continues well into the mid-twenties. For adolescents, this means that the pruning down of existing neurons and the laying down of myelin sheaths connecting the remaining linked neurons will continue years after we stop referring to them as teenagers. Dr. Dan Siegel

Two processes are happening simultaneously, and both matter enormously.

Synaptic pruning — which is, at this stage, extraordinarily active — is the brain's aggressive specialisation programme. Unused connections in the thinking and processing part of the brain are pruned away, whilst other connections are strengthened. This is the brain's way of becoming more efficient, based on the "use it or lose it" principle. The brain is not discarding learning at random. It is specialising — retaining and reinforcing what has been most consistently practised and experienced, whilst eliminating what hasn't. Raising Children Network

The critical implication of this: repeated activation of a specific collection of neurons as a result of engaging in a particular behaviour will actually strengthen the connections among those neurons. Behaviours that have been rehearsed frequently — including, notably, highly self-rewarding instinctive behaviours like chasing, scavenging, and reactive barking — are not being pruned. They are being consolidated. ASCD

Myelination is the second process. Myelin is white fatty tissue that encases the projections of neurons that interconnect them, acting like plastic insulation around an electrical wire, increasing the speed of neural impulses and improving information transmission. As Dr Daniel J. Siegel — clinical professor of psychiatry at UCLA and author of Brainstorm: The Power and Purpose of the Teenage Brain — describes it: practice lays down myelin to enable a skill. The pathways that fire most often become the fastest, most efficient routes the nervous system takes. ASCDPsychology Today

Here is where it becomes complicated, and where the puzzle analogy earns its keep.

The puzzle pieces are still there. The picture you were assembling during puppyhood — the reliable recall, the solid sit, the loose lead — it still exists. The neural connections have not been destroyed. But the renovation has temporarily disturbed the whole structure. Some connections are being reinforced, some are being pruned, and crucially — as we will come to — this pruning process begins at the back of the brain. The front part of the brain, the prefrontal cortex, is remodelled last. Raising Children Network

And that, as it turns out, changes everything.

Because the reassembled picture may not look quite like the one you had before. What emerges from a well-supported adolescence is often more integrated, more resilient, and more genuinely reliable under pressure than what went into it. The renovation, done properly, produces something better than the original.

Done badly — with punishment, inconsistency, or abandoned training — the picture comes back together differently. Poorly developed pathways. Pruning that consolidated fear or reactivity rather than regulation. A dog who was not well-supported during the only period when it truly mattered.

PART THREE: THE EMOTIONAL BRAIN WENT OUT TO LUNCH (And Left The Volume Turned Up)

I want to introduce what I consider the most important concept in understanding adolescent behaviour, in any species.

During adolescence, there is a fundamental mismatch between two systems.

The emotional and motivational brain — the limbic system, which governs drives, emotional responses, reward-seeking, fear, and biological impulses — develops and becomes active relatively early. In the adolescent, it is, as Oliver put it,

fully online, with its volume turned up

— his words, not mine, though I will concede they are accurate.

The amygdala — the fight or flight part of the brain involved in emotional processing — is more developed during this period than the prefrontal cortex, so we see a lot of "big" emotions in our teenage dogs. ChalklandVets

The prefrontal cortex, meanwhile, which is responsible for impulse control, decision-making, weighing consequences, and — critically — sustained behavioural regulation — has, in Oliver's equally accurate formulation:

gone out to lunch.

Myelination of the prefrontal cortex continues well into late adolescence and early adulthood. More efficient neural connections within the prefrontal cortex are important for higher-order cognitive functions — planning ahead, weighing risks and rewards, and making complicated decisions. Issues

During canine adolescence, the area of the brain that influences cognition, social behaviour and decision-making is not yet fully developed, and the part of the brain that influences arousal and reward-seeking behaviour shows increased activity. Because of this, adolescent dogs may display behaviours similar to what we would expect to see in human teenagers — increased impulsivity and a higher likelihood of risk-taking. Instinct Dog Behavior & Training

This brings us to an aspect of adolescence that does not receive nearly enough attention in discussions of dog training, but which Siegel addresses directly in Brainstorm: risk-seeking.

Adolescents are three times more likely than adults or children to suffer serious injury or death. Risks, and the rewards adolescents associate with taking risks, come from innate changes in brain development during this phase of life. ParentMap

In human teenagers, this manifests as the kinds of behaviour that prompt parents to lie awake at night. In adolescent dogs, it manifests as: ignoring the recall to investigate something far more interesting. Running into traffic. Straying further than ever before. Testing other dogs in ways a puppy never would. Launching across a room after a moving object despite having, just two seconds ago, performed a perfect sit.

This is not defiance. It is biology. An adolescent dog's brain is wired for exploration, risk-taking, and heightened emotional sensitivity. It is an evolutionary trait that encourages young animals to leave the safety of their birth environment and learn how to navigate the world independently. Pupford

Siegel makes an observation that I find rather profound:

the only thing more dangerous than the dangerous things adolescents do is not doing them. Risk-seeking is the developmental mechanism by which any young animal learns to exist in the world without constant parental scaffolding.

In the wild, it is essential. In a domestic dog, it requires management, guidance, and a great deal of patience. Google

The adolescent brain's sensitivity to dopamine peaks during this period — dopamine being involved in reward circuits — so the possible rewards outweigh the risks. Lumen Learning

In other words: the ball is more rewarding than you are, at this particular moment. This is not a relationship problem. It is a dopamine problem.

PART FOUR: THE EVIDENCE (For Those Who Require It)

I do not typically defer to external authority, but in the interests of rigour I will acknowledge that there is solid empirical support for everything I have described.

In 2020, Dr Lucy Asher of Newcastle University, working with colleagues from the University of Nottingham and the University of Edinburgh, published the first study to find empirical evidence of adolescent behaviour in dogs. EurekAlert!

The researchers studied dogs at pre-adolescence — five months of age — and during adolescence at eight months, measuring their response to the established "sit" command given by both their owner and a consistent stranger. nih

Dogs were harder to train and less responsive to commands during adolescence — but only when the command was given by their caregiver, not a stranger. The dogs were not randomly less responsive. They were specifically, selectively less responsive to the person they knew best. The pattern is almost identical to human parent-teen conflict. ncl

There is something else buried in this data that I want to draw your attention to, because I think it will feel familiar to a significant number of you.

If you have ever taken your adolescent dog to a training class and watched them perform faultlessly for an instructor — whilst you stood to one side thinking: that is not the animal I live with — this is why.

And if you have ever been the parent of a human teenager, or known one well, you will recognise the phenomenon immediately.

Other parents adore your teenager. They tell you what a delight he is, how polite, how thoughtful, what a pleasure to have around. You smile and nod and wonder, privately, whether they have met your actual child. What, my son? He's never that good for me.

Adolescent conflict — in dogs as in humans — is not distributed evenly. It concentrates, with some precision, in the direction of the primary attachment figure. The one who has been there from the beginning. The one whose instructions carry the greatest emotional weight — and therefore the greatest potential for resistance.

This is not betrayal. It is, neurodevelopmentally speaking, exactly what is supposed to happen. The behaviour changes seen in dogs closely parallel those of parent-child relationships, as dog-owner conflict is specific to the dog's primary caregiver.

Your dog is pushing against the relationship that matters most to them. Which is, if you can manage to find it useful rather than infuriating, a form of compliment. EurekAlert!

Dr Naomi Harvey of Nottingham noted that just as with human teenagers, this is a passing phase. EurekAlert!

And the practical implication for anyone tempted to respond to adolescent regression with punishment: it is extremely important that owners do not punish their dogs for disobedience or start to pull away and disengage from them at this time, as this would be likely to make problem behaviour worse in the long run. ncl

A nervous system under punishment becomes less regulated, not more.

The prefrontal cortex, already under renovation, functions even less effectively under stress. You are, in effect, attempting to fix the electrics during a power cut.

PART FIVE: THE YOUNG COCKER AND THE LEAKING CIRCUIT

Let us now return to the session Oliver was running, because I believe it illustrates everything above with unusual precision.

A young Cocker Spaniel was being asked to sit and remain still whilst a ball was thrown.

This is not, on paper, a complex ask. He had done it before. He had done it several times that very session.

He sat. The ball was thrown. It landed. He remained still.

Two seconds passed.

Then he launched himself after the ball as if the previous two seconds had never occurred.

Oliver drew two lines side by side on his whiteboard to explain it.

The old circuit — the chase response, encoded across generations of selective breeding, rehearsed thousands of times across his life, deeply myelinated and biologically efficient.

And the new circuit — the trained sit-and-wait behaviour, real and functional, but more recently established and not yet carrying equivalent insulation or conductivity.

The intrinsic genetic motivation — the chase drive — builds current. And under sufficient arousal, that current finds the path of least resistance. Which is, inevitably, the older, more established circuit.

The current leaked.

This is not a metaphor for a broken dog.

It is a metaphor for a dog whose regulation pathway, whilst present, had not yet been sufficiently developed to hold inhibition under sustained motivational load. The immature prefrontal cortex has an influence on learning, and training regression occurs because short-term memory and impulse control are still developing. ChalklandVets

What made this moment genuinely fascinating — and what I want owners to appreciate — was the two-second pause.

He did not simply lunge at the ball. He sat, whilst the ball landed, and he held that position before the old circuit eventually pulled through.

That pause is not failure. That pause is evidence that the regulation pathway exists. It fired. It held — briefly — against significant motivational competition. What it could not do was sustain that hold as arousal continued to build.

This distinction matters enormously. Because it means:

Training did not fail. Reliability under emotional load is not yet established.

Those are different problems.

They require very different responses.

PART SIX: WHAT THIS MEANS FOR YOUR DOG

If you are living with an adolescent dog, here is what I would have you understand.

• The puzzle pieces are still there. When your dog seems to have forgotten everything, they have not. The neural connections exist. The renovation has temporarily destabilised the structure.

Your job is to help reassemble it — consistently, patiently, with enough successful repetitions that the new pathways develop the insulation they need. The picture that emerges may look slightly different from the one you had before.

With good support, it will be better.

• First response versus sustained regulation. Your dog may be able to briefly perform a behaviour before the emotional system reasserts the older pattern. That brief compliance is meaningful — it tells you the pathway is there. It needs more rehearsal, more reinforcement history, and more practice under gradually increasing emotional load before it becomes reliably durable.
• Arousal is the test. A behaviour that is reliable in the garden may fall apart at the park. This is not inconsistency in your dog — it is the nervous system revealing exactly where development is still incomplete. Read it as diagnostic information rather than failure.
• Every successful repetition is insulation. Rehearsal that ends successfully — the dog makes the regulated choice, is reinforced, the session ends well — physically builds the efficiency of the desired pathway. This is not a metaphor. Both synaptic pruning and myelination are influenced by experience, such that repeated activation of a specific collection of neurons as a result of engaging in a particular behaviour will strengthen the connections among those neurons. ASCD
• Management is maintenance. Every time a self-rewarding, instinctive behaviour fires — a chase sequence completed, a reactive response rehearsed, a recall ignored — that old circuit becomes marginally more efficient. Management during adolescence is not permissiveness. It is pathway maintenance.
• Punishment worsens what it intends to fix. The prefrontal cortex is already under construction. Punishment adds stress to a system that is already struggling to regulate. It does not build inhibitory control. It undermines it.

A FINAL NOTE ONBRAINSTORM

Brainstorm: The Power and Purpose of the Teenage Brain by Daniel J. Siegel was written for parents of human teenagers.

In it, Siegel challenges the commonly held myth that adolescence is merely a stage of immaturity filled with often "crazy" behaviour, arguing instead that adolescence is a formative period during which vital skills are learned. Barnes & Noble

I recommend it unreservedly to dog owners. The neurological processes Siegel describes — the remodelling brain, the mismatch between emotional drive and regulatory control, the risk-seeking imperative, the importance of understanding rather than pathologising regression — are directly applicable to what we observe in our adolescent dogs. If you also have a human teenager in the house.

I am told it is additionally illuminating on that front.

Possibly more so.

Not that I have personal experience of any of this.

I did not go through adolescence.

I was always like this.

Although...

Thinking about it rather carefully...

The intellectual curiosity. The sophisticated social awareness. The capacity for deep investigative thought. The distinctive personal authority that some find overwhelming but most recognise as a gift.

These qualities were not, if I am being precise, particularly evident in photographs of me at approximately six months of age.

In those photographs I appear to be attempting to eat a cushion.

It is possible — and I offer this purely as a theoretical observation — that the renovation produced something.

That the puzzle, scattered across the floor and painstakingly reassembled, came back together into a more refined and distinguished picture than the one that preceded it.

It is possible that I did not emerge from puppyhood fully-formed.

It is possible that adolescence made me.

I will not be taking questions on this matter.

Percy is resident Panorama Correspondent at Dog Smart Training & Behaviour. His investigations are conducted with rigorous impartiality and absolutely no personal bias whatsoever.

REFERENCES

Books

Siegel, D.J. (2014). Brainstorm: The Power and Purpose of the Teenage Brain. Tarcher/Penguin, New York.

Peer-Reviewed Research

Asher, L., England, G.C.W., Sommerville, R., & Harvey, N.D. (2020). Teenage dogs? Evidence for adolescent-phase conflict behaviour and an association between attachment to humans and pubertal timing in the domestic dog. Biology Letters, 16, 20200097. https://doi.org/10.1098/rsbl.2020.0097

Academic & Professional Sources

Siegel, D.J. (2014). Pruning, myelination, and the remodeling adolescent brain. Psychology Today / drdansiegel.com https://drdansiegel.com/pruning-myelination-and-the-remodeling-adolescent-brain/

Siegel, D.J. (2020). The ESSENCE of adolescence. drdansiegel.com https://drdansiegel.com/the-essence-of-adolescence/

Steinberg, L. Should the science of adolescent brain development inform public policy? Issues in Science and Technology. https://issues.org/steinberg-science-adolescent-teenage-brain-policy/

Berger, K.S. Demystifying the adolescent brain. Educational Leadership / ASCD. https://ascd.org/el/articles/demystifying-the-adolescent-brain

Cleveland Clinic. What is synaptic pruning and why does your brain do it? (2026). https://my.clevelandclinic.org/health/articles/synaptic-pruning

Lumen Learning. Adolescent brain. Lifespan Development. https://courses.lumenlearning.com/suny-lifespandevelopment/chapter/adolescent-brain/

Raising Children Network. Teenage brain development. (2018). https://raisingchildren.net.au/pre-teens/development/understanding-your-pre-teen/brain-development-teens

Canine-Specific Sources

Instinct Dog Behavior & Training. Adolescent dogs. https://www.instinctdogtraining.com/expertise/adolescent-dogs/

Pupford. Canine adolescence: understand why your dog acts like a teenager. (2025). https://pupford.com/blogs/all/canine-adolescence

Chalkland Vets. Canine adolescence — dude, where's my prefrontal cortex? (2025). https://chalklandvets.co.uk/2025/02/27/canine-adolescence-dude-wheres-my-pre-frontal-cortex/

Newcastle University Press Office. Adolescence is ruff on dogs too. (2020). https://www.ncl.ac.uk/press/articles/archive/2020/05/teenagedogs

Note for the reference section: The Asher et al. (2020) paper is the only formal peer-reviewed canine study cited