“What Do We Lose, and What Do We Keep?”: Remembering Bente Pakkenberg’s Legacy in Brain Ageing

In the history of neuroscience, few voices have combined quantitative precision with bold curiosity quite like the late Professor Bente Pakkenberg. A pioneer in the field of neurostereology, she revolutionised our understanding of the ageing brain, dedicating her life to mapping its intricate architecture with clarity and compassion.

Through meticulous stereological analyses of over 1,400 human brains, she charted how neuron numbers change over time. Her research revealed a 10% loss of neocortical neurons with age, yet fascinatingly, those who reached 100 years of age experienced no additional decline after age 90. This raised profound questions about cognitive reserve, resilience, and the biology of successful ageing.

Pakkenberg’s findings went further, showing that while fetal brains accumulate an average of 171 million neurons per day from week 22 until birth, adult brains retain the full neuronal count even as glial cell populations triple. Such data challenge simplified narratives of brain development and loss, offering instead a layered picture of neuroplasticity, support systems, and functional adaptation.

Her voice continues to echo not just in the field of ageing but in feminist neuroscience. She showed us that it’s not the number of neurons that defines capacity, but how they are used, supported, and sustained across a lifetime. In a field often overrun by reductionism, Bente Pakkenberg brought clarity, nuance, and a rare poetic truth.

She passed away in 14 April 2023, but the legacy she leaves is neuronal, indeed: enduring, deeply interconnected, and quietly powerful.

Written in remembrance — and admiration.

Pinar Sengul ~ Neuroscientist

Why I Don’t Believe in the Title ‘Child and Adolescent Therapist’

It’s written everywhere—on clinic doors, websites, LinkedIn bios:
“Child and Adolescent Therapist.”

But as someone deeply committed to developmental neuroscience and therapeutic integrity, I’ll say this clearly:

Children and adolescents are not the same.
And pretending they are does a disservice to both.

The Brain Doesn’t Lie

A child’s brain and a teenager’s brain are not simply younger or older versions of each other. They are fundamentally different organisms in terms of structure, function, and regulation.

1. Myelination: Speed of Thought
In early childhood, the brain’s executive functions are still under construction. Myelination—the process that speeds up neural communication—is slow and uneven. Children live in the world of now, with limited foresight or inhibition. They don’t just need therapy; they need your nervous system as an anchor.

In adolescence, the emotional brain (limbic system) races ahead, while the prefrontal cortex (rational control) lags behind. This creates the infamous teenage turbulence: intense emotion with minimal regulation. Here, the therapist becomes a boundary-holder, not a co-regulator.

2. Synaptic Pruning: Jungle vs. Garden
Children’s brains are like a lush jungle—bursting with synaptic connections. They’re wide open, absorbing everything. Therapy must be sensory-rich, structured, and playful.

Teenagers, however, are pruning the excess. Their brains are streamlining—deciding who they are, what they care about, and what gets cut. Therapy here must honour identity exploration, autonomy, and cognitive sophistication. Clay and metaphor won’t reach a defended 16-year-old struggling with existential dread.

3. Limbic–Cortical Integration: Emotions vs. Reason
Children externalise emotion. Their regulation is social—dependent on attachment and sensory cues. Therapy must include the body, breath, symbol, and parent.

Adolescents internalise and intellectualise. They test boundaries. They want a witness, not a playmate. They need someone who won’t flinch at their rage, sarcasm, or silence.

The Therapist Must Choose

Of course, some clinicians do shift masterfully between child and adolescent work. But it’s rare. The posture, method, and energy required for each is distinct. Personally?

I am a co-regulator. I work best when I can meet a child in their emotional rawness, build symbolic bridges, and offer a nervous system steadier than their own.

Does that mean I don’t work with teens? Not necessarily. But it does mean I choose with intention—not branding.

Let’s Be Honest About Specialisation

The title “Child and Adolescent Therapist” may serve paperwork and marketing. But in practice, we owe our clients more precision. Children don’t need someone who tolerates play. They need someone who thrives in it. Adolescents don’t need someone who enjoys deep talk. They need someone who can survive the storm of separation and self-definition.

If we are to be ethically aligned with brain development, we must be willing to say:
“I specialise in children.”
or
“I specialise in adolescents.”
or
“I know where my skill ends—and I refer with respect beyond it.”


This is not about superiority. It’s about specificity. Children and adolescents are both sacred, sensitive stages. They deserve therapists who speak their language—neurologically, emotionally, and relationally.

Let’s stop selling ourselves short with generic titles.
Let’s claim who we truly serve—and serve them with everything we’ve got.

π