Between adolescence and adulthood

Sonya Black shares some insights into this transitional and transformative time…

I wish I had known that the human brain continues to develop well into the mid-twenties. It would have helped explain why the years between 18 and 24 feel so uncertain, overwhelming and at times, chaotic.

Research in neuroscience, particularly the work of Professor Sarah-Jayne Blakemore, shows that the prefrontal cortex, the part responsible for planning, impulse control, and decision-making, is one of the last areas to fully mature.

Psychotherapy with young people in this age bracket, especially those aged 18–22, therefore meets them right in this transitional space – no longer adolescents, but not yet fully established adults.

This in-between phase brings challenges, but also huge potential for growth.

Developmental psychologists call this stage ’emerging adulthood’. It is characterised by experimentation, instability, and identity exploration. At 18, you may be expected to decide on a degree, career path, or where to live. Yet the brain is still building the very capacities that help us weigh risks, plan ahead and manage complex emotions.

For many young people, this mismatch between expectations and readiness creates anxiety, self-doubt and confusion. There is an expectation to act like adults, while still learning how to think, feel, and cope like one. Therapy provides a grounding bridge between these worlds. There can also be a realisation at this age, that ‘adulting’ is repetitive, tiring – work, chores, study, socialise repeat and perhaps not what they expected.

Therapy as a bridge

In psychotherapy, young people have space to explore questions that don’t always have immediate answers:

• Who am I becoming?
• What do I want to do with my life?
• How do I manage the pressure of independence?

Unlike therapy with under-18s, where parents or carers are often involved, work with 18–22-year-olds focuses more directly on autonomy. Yet it also honours the continuing pull of family, peers and educational pressures. The therapeutic space becomes a rehearsal room for adulthood, where thoughts can be tested, emotions unpacked and decisions explored without fear of failure.

CBT as a toolbox for life
I often describe CBT as a toolbox for life. It equips young people with practical skills to understand the links between thoughts, feelings and behaviours and to experiment with healthier ways of responding.
So many times in sessions I’ve heard a variation of the same reflection: ‘Why wasn’t I taught this at school? This would have changed how I lived my life.’

That’s the power of CBT, it doesn’t just address current difficulties, it provides strategies that can be carried into every stage of adulthood. From managing anxious spirals to building confidence in decision-making, CBT offers lifelong resources.

Common themes in early adult therapy
When I sit with young people in this age group, certain threads appear again and again. Questions of identity often surface, what does it mean to step away from the labels of childhood and begin to define yourself on your own terms?

Alongside this runs the uncertainty of education or work: university choices, first jobs, or the unsettling possibility of not knowing what comes next.

Relationships shift, too. Parents may still play a central role, yet the pull towards independence is strong. Romantic partnerships begin to take on new weight, and friendships can feel both grounding and fragile as lives move in different directions.

Then there is the quiet pressure of independence, the reality of rent, bills, deadlines, and the practicalities of adult life pressing against the unfinished scaffolding of a still-developing brain.

For some, these pressures spill into anxiety, low mood, or intrusive thoughts. For others, unhelpful coping strategies emerge, avoiding responsibilities, experimenting with substances, or retreating into comparison.

Yet, beneath all this complexity, there is also immense possibility. These themes are not just problems to be solved; they are invitations to grow, to experiment, and to build a way of being that feels authentic and sustainable. Therapy offers a safe space to weave these threads together into a clearer picture of who a person is becoming.

Why this stage matters

Once someone turns 18, they can easily fall through the cracks. Adolescent services end, adult services may feel inaccessible and the unique needs of emerging adults get overlooked. Yet this is a period when early interventions can make the most difference. Supporting a young person at this stage can change the trajectory of their wellbeing, relationships, and future choices.

By giving attention to the in-between years, psychotherapy honours the reality that adulthood is not a moment, it’s a gradual process of becoming. Therapy meets young people where they are, rather than where society assumes they should already be.

The evergreen brain
One of the most hopeful insights from neuroscience is that our brains are not static. Neuroplasticity means that even in early adulthood, and well beyond, we can form new pathways, build healthier habits, and reshape the way we respond to the world.

I often describe the brain as evergreen. Just like a tree that continues to grow and renew its leaves, our brains retain the capacity for change across the lifespan. For young people in their late teens and early twenties, this is particularly powerful to know. You are not locked into old patterns. The mistakes you made as a teenager don’t define you. The ways you’ve learned to cope so far, whether through avoidance, self-criticism, or unhealthy habits can be changed.

Moving forward
Psychotherapy for 18–22-year-olds isn’t about ticking developmental boxes. It’s about creating space for curiosity, reflection, and growth. It’s about equipping young people with the tools they need—not only to cope with today’s challenges, but to navigate the ever-evolving path into adulthood.

Perhaps most importantly, it reassures them: you don’t need to have it all figured out yet. Your brain, your identity, and your life are still taking shape. Therapy is here to walk alongside you as you build the foundations of who you are becoming.

This is where CBT comes in. Each strategy added to the toolbox for life, strengthens those neural pathways, making resilience and self-compassion more available in daily life. Therapy, in this sense, isn’t about fixing what is broken; it’s about nurturing the brain’s natural ability to adapt, rewire, and grow.

Sonya Black is a Cognitive Behaviour Therapist at our Tunbridge Wells centre, sonyacbt.com / @sonyacbt / sonyablack.substack.com/p/welcome