We tend to think of insomnia, depression, and anxiety as separate struggles. Different symptoms, different stories, different strategies. But what if they’re all playing out variations on a common theme rooted in how the brain handles sleep and mental health?
A recent study involving over 25,000 adults peels back the layers on this question. Instead of focusing on diagnoses, researchers looked at symptom ratings, which show people actually feel and combined that with brain scans measuring structure, connectivity, and reactivity. What emerged is a compelling picture of shared biology and a powerful new way to think about sleep and mental health.
The Thread That Ties Them Together
Across all three conditions, a consistent stress-related brain pattern stood out. Whether someone’s losing sleep, losing motivation, or battling anxious thoughts, there’s a recognizable neural signature showing up. It’s as if the brain is stuck in a particular “stress gear,” and each condition reflects a different way of coping (or not coping) with that setting. This shared signal may explain why sleep and mental health challenges so often overlap.
Let’s break it down.
Insomnia: The Brain That Won’t Power Down
This makes insomnia not just a nighttime nuisance, but a vital clue in the larger sleep and mental health puzzle.
Depression: A World Dimming at the Edges
This deeper look at brain structure helps explain why sleep and mental health aren’t just linked but deeply intertwined.
Anxiety: A Mind on High Alert, But Under-Connected
When we zoom out, anxiety also fits into the broader sleep and mental health landscape. The hypervigilance seen in anxiety often spills into the night, sabotaging rest and further stressing the nervous system.
Why This Matters
If you’re a coach, a therapist, or simply someone who wants to support mental wellbeing more effectively, this research offers three takeaways:
- 1Address sleep, even if mood is the headline complaint. Insomnia isn’t just a side effect; it’s often a key player in the story of sleep and mental health.
- 2Emotion regulation is a power tool. Because it’s implicated across anxiety, depression, and insomnia, strengthening emotional skills can move the needle in more than one direction.
- 3Think in systems, not symptoms. These conditions don’t live in isolation. Neither should our interventions.
In short, the brain doesn’t sort our mental health struggles into neat categories. And neither should we. By understanding the shared stress patterns that underlie sleep and mental health, we move closer to solutions that are as interconnected as the challenges themselves.
Reference:
Lange, S. C. de, Tissink, E., Bresser, T., Savage, J. E., Posthuma, D., Heuvel, M. P. van den, & Someren, E. J. W. van. (2025). Multimodal brain imaging of insomnia, depression and anxiety symptoms indicates transdiagnostic commonalities and differences. Nature Mental Health, 3(5), 517–529. https://doi.org/10.1038/s44220-025-00412-8