- Severe symptoms across disorders link to same brain and genetic patterns
- Helps young adults facing psychosis, depression, or early mental illness
- Not a treatment yet — but could change how we diagnose and treat
This could explain why different mental illnesses feel so similar in early stages.
You’re a 22-year-old who’s been feeling off for months. Sleep’s a mess. You’re withdrawing from friends. Some days, you hear whispers that aren’t there. Other days, you can’t get out of bed.
You don’t know if it’s depression. Or the start of something like schizophrenia. Your doctor isn’t sure either. So you wait. You try one medication, then another.
But what if the type of diagnosis isn’t the most important thing — at least at first?
Millions of young people struggle with early mental health changes. They may show signs of psychosis, depression, or both. Right now, doctors treat them as separate illnesses — even when symptoms overlap.
But many don’t respond well to first treatments. It can take years to find what works. That delay can make recovery harder.
Current labels — like “depression” or “psychosis” — don’t always match what’s happening in the brain. They’re based on symptoms, not causes. And two people with the same diagnosis may have very different experiences.
What if we looked past the label?
The surprising shift
For years, experts believed psychosis, depression, and anxiety were distinct. Each had its own treatment path. But newer research shows heavy overlap — especially early on.
Many people at risk for psychosis also have severe depression. And those with early depression sometimes develop psychotic symptoms. The lines blur.
But here’s the twist: this study didn’t start by asking, “Is it psychosis or depression?” Instead, it asked: How severe are your symptoms — no matter the diagnosis?
What scientists didn’t expect
They grouped people by symptom severity — not diagnosis. From none to mild, moderate, and severe. These groups cut across traditional lines: some had psychosis risk, others recent depression, others no diagnosis at all.
Then they looked at four key things: How well they functioned before symptoms. How they changed over 18 months. Their genetic risk. And their brain scans.
The result? The severity of symptoms — not the diagnosis — predicted outcomes.
Hidden patterns in genes and brain
People with more severe symptoms had three key things in common. First, they struggled more as kids and teens — even before symptoms started. Second, their condition worsened over time. Third, they had higher genetic risk for mental illness — not just for one disorder, but across schizophrenia, depression, and other conditions.
And their brains showed less grey matter. This was true across diagnoses — whether they were labeled “depression” or “psychosis risk.”
Think of it like a car with low fuel. You can drive a sedan or an SUV. But if the tank is near empty, both will stall. Here, symptom severity may be the “low fuel” signal — a sign the brain is under strain, no matter the diagnosis.
This doesn’t mean this treatment is available yet.
The study included nearly 750 young adults. Most were in their early 20s. They came from four groups: at high risk for psychosis, early psychosis, early depression, and healthy controls.
At the start, researchers measured positive symptoms (like hallucinations), negative symptoms (like lack of motivation), and depression (like sadness and hopelessness). Then they grouped people by overall severity — no, mild, moderate, or severe.
Over 18 months, those in the severe group got worse. They had more trouble working, studying, and connecting with others. Their symptoms didn’t improve as much as those in milder groups.
They also had higher polygenic risk scores. That means their DNA carried more tiny genetic changes linked to mental illness. And brain scans showed lower volume in areas tied to thinking, emotion, and self-awareness.
But there’s a catch.
These patterns weren’t tied to any one diagnosis. They showed up across psychosis and depression groups. Even some “healthy” controls in the severe symptom group had similar risks and brain changes — but hadn’t been diagnosed yet.
This supports a growing idea: early mental illness may be less about what you’re diagnosed with — and more about how much your brain is struggling.
It’s not that diagnoses are useless. But they might come too late — after the system is already under strain.
By focusing on severity first, doctors might catch problems earlier. And treatments could target the shared roots — like brain inflammation, stress response, or neural connectivity — instead of just symptoms.
This isn’t a new treatment. You can’t get a “severity score” at your doctor’s office yet. And you shouldn’t ignore a diagnosis.
But it may change how experts think about early care. Instead of waiting for a clear label, doctors might start asking: How severe are your symptoms — and how much is your brain under pressure?
If you or a loved one is struggling early on, talk to your doctor about symptom patterns — not just labels. Ask about support for functioning: sleep, social life, daily tasks. These may matter just as much as symptom type.
The full picture isn’t clear yet
The study has limits. It only followed people for 18 months. Longer data is needed to see who recovers — and who doesn’t.
Most participants were from Europe. Results may differ in other groups. And brain scans can’t prove cause — just links.
Still, findings were replicated in a second group of over 600 people. That makes the results more trustworthy.
This idea needs testing in real clinics. Researchers must check if treating “severity” — not just diagnosis — leads to better outcomes. New tools may emerge to measure brain strain early. But for now, it’s a shift in thinking — not a new standard of care.