We all occasionally experience a night of poor sleep. This isn’t a problem if it happens every now and then. However, if it occurs more frequently and you have trouble sleeping for more than three nights a week for over a period of three months, we call it insomnia. Insomnia, also known as sleeplessness, is the most common sleep disorder and poses a serious chronic problem for around 10% of the population. Yet, the underlying brain mechanisms remain poorly understood. A new study shows that we cannot group all people with insomnia together.
Five groups based on personality and mood
In previous research from the Netherlands Institute for Neuroscience, Tessa Blanken discovered five types of insomnia. All types were associated with the same sleep complaints but differed in personality and mood. Colleague researcher Tom Bresser thought that their MRI brain scans should also be examined separately. 'I wanted to know if the location of the brain’s white matter deviates between these five types.. It turns out it does!' Bresser shares enthusiastically. 'We saw that the limbic circuit, important for emotions, has more abnormal connections in insomnia types that report fewer positive emotions. For each type, we saw different circuits with different abnormalities. If we hadn’t made distinctions and had lumped all types together, most indications of different biological vulnerabilities would have gone unnoticed.'