On 12 October 2026, Medical Xpress published an article from the University of Western Australia (UWA) suggesting that treating insomnia could be a key to easing depression. But the new study behind it asks a more precise question: when mood lifts during insomnia treatment, what actually changes?
What the Researchers Did
The study was led by Vanika Lall, a researcher at UWA's School of Psychological Science, with Melissa Ree (also affiliated with Sleep Matters in Perth) and Romola Bucks. It appears in the journal Behaviour Research and Therapy.
The team followed 88 adults (72% women) with both poor sleep and depressive symptoms who took part in cognitive behavioural therapy for insomnia, or CBT-I. According to the university, this was a short, structured four-week programme called Sleep Well for Mood. Participants answered questionnaires before treatment, just after it, and again 12 weeks later.
The researchers were less interested in whether CBT-I works, which is already well established, than in how it might help mood. They tracked two possible ingredients:
- Repetitive negative thinking: worry and rumination, both in general (going over problems at bedtime, for example) and about sleep itself (worrying during the day about how badly you will sleep tonight).
- Activity levels: time spent on meaningful activities, such as physical and social ones.
What They Found
- Depressive symptoms fell in a clinically significant way during and after CBT-I, alongside improvements in insomnia.
- Repetitive negative thinking decreased, both in general and about sleep, and activity levels rose.
- People whose daytime worry about sleep, and whose general negative thinking at bedtime, eased faster also tended to see their depression improve faster. These links were strong.
- People whose activity levels rose faster also improved faster, a moderate link.
Vanika Lall summed up the idea in one line: "Negative thinking and an inactive lifestyle fuel depression." In other words, CBT-I may help mood partly by quieting the mental loops around sleep and by helping people move and engage with life again.
Reading the Results Carefully
This is encouraging, but this particular study has clear limits:
- No control group. Everyone received CBT-I. Without a comparison group, the study cannot show how much of the improvement came from the treatment rather than from time, natural recovery or other support.
- Associations, not proof of mechanism. Negative thinking and depression improved together, which does not prove that one drove the other. The authors themselves call their findings preliminary and ask for experimental studies to test these mechanisms.
- A modest sample. 88 people, mostly women, in one Australian programme.
What Stronger Evidence Already Shows
The case for treating insomnia does not rest on this one study. CBT-I is the recommended first-line treatment for chronic insomnia in adults, both in the 2023 European Insomnia Guideline of the European Sleep Research Society and in the 2016 guideline of the American College of Physicians.
Randomised trials also suggest that better sleep can protect mood. In a 2022 trial published in JAMA Psychiatry, 291 adults aged 60 and over with insomnia received either CBT-I or sleep education. Over three years of follow-up, 12.2% of the CBT-I group developed major depression, compared with 25.9% of the sleep education group.
And Exercise?
Another study made the rounds the same weekend: on 11 October 2026, ScienceDaily reported that people who exercised more often got more deep sleep. This research, by Christian Corral, Benjamin Baird and colleagues at the University of Texas at Austin, was in fact published in 2025 in the Journal of Physical Activity and Health. It followed 69 young adults (average age 21.5) who wore a Fitbit over eight months. When people were active on more days, with at least 10 minutes of moderate-to-vigorous activity, the first hours of their night contained proportionally more non-REM sleep, the stages that include deep, slow-wave sleep.
It is a small, observational study of students, and consumer wearables only estimate sleep stages, so it does not prove that exercise causes deeper sleep. But it points the same way as the CBT-I findings: regular, modest activity seems good for both sleep and mood.
Sleep Problems Are Common in ADHD and Autism
Research consistently finds poorer sleep in adults with ADHD or autism, often linked to a later body clock or a mind that will not switch off at night. We have looked at this in sleep, body clock and mental health in autism and ADHD and in insomnia in ADHD and autism, and what taurine and magnesium actually do.
What This Means for You
- Keep a regular rhythm. Getting up at the same time every day, weekends included, is one of the simplest foundations for better sleep.
- Know what CBT-I involves. It is more than sleep hygiene tips. A typical programme combines sleep education, a personalised sleep schedule (sometimes temporarily shortening time in bed so that sleep becomes more solid), keeping the bed for sleep, relaxation, and work on worries and beliefs about sleep. It is offered one-to-one, in groups or online. Shortening time in bed can make you sleepier at first, so it is best done with professional guidance.
- Track your nights. Our free 14-day sleep diary is the kind of record sleep clinicians ask for.
- See a doctor if poor sleep happens at least three nights a week for three months or more, if you snore loudly or stop breathing during sleep, or if low mood lasts more than two weeks. If you have thoughts of harming yourself, seek help right away from emergency services or a crisis line.
This article is not medical advice. Do not start, stop or change any medication without talking to the person who prescribes it.
To take stock, our free sleep quality test takes about 6 minutes, and the PHQ-9 depression screener (9 questions, about 5 minutes) helps you put words to your mood over the last two weeks. If your score is high, the results page points you to support. Screening tests are not a diagnosis, but they are a good starting point for a conversation with a professional.
Source: Lall V, Ree MJ, Bucks RS (University of Western Australia). Cognitive and behavioural factors associated with improvements in depression outcomes among individuals attending CBT for insomnia. Behaviour Research and Therapy 205:105146 (2026), DOI 10.1016/j.brat.2026.105146. Longitudinal study of 88 adults with insomnia and depressive symptoms attending CBT-I (no control group), assessed before treatment, after treatment and at 12-week follow-up. Reported by Medical Xpress (University of Western Australia), 12 October 2026. Exercise and sleep: Corral CJ, Miller M, Champagne FA, Schnyer DM, Baird B (University of Texas at Austin). Physical Activity Frequency Patterns Influence Sleep Architecture in Young Adults. Journal of Physical Activity and Health 22(8):1042-1050 (2025), DOI 10.1123/jpah.2024-0844 (observational, 69 young adults; reported by ScienceDaily, 11 October 2026). Background: Irwin MR et al. JAMA Psychiatry 79(1):33-41 (2022), DOI 10.1001/jamapsychiatry.2021.3422 (randomised trial, 291 adults aged 60+). Riemann D et al. The European Insomnia Guideline 2023. Journal of Sleep Research 32(6):e14035 (2023), DOI 10.1111/jsr.14035. Qaseem A et al. (American College of Physicians). Annals of Internal Medicine 165(2):125-133 (2016), DOI 10.7326/M15-2175.