By Natasha Fiera
Ever had difficulty getting to sleep or staying asleep? The brains of insomniacs have been scanned and shown to have looser connections in the right hemisphere when compared with healthy sleepers.
Approximately five per cent of the population suffer with insomnia and it is the most common sleeping disorder in the UK. Insomnia is characterised by sleeplessness and the inability to fall or stay asleep, although it often remains unrecognised and untreated.
Persistent insomnia can have a significant impact on the quality of life – limiting your ability to function during the day, affecting your mood and leading to problems in relationships. Individuals with insomnia are also five times more likely to suffer from anxiety and depression if it is left untreated. It can also increase the risk of developing other diseases such as diabetes, hypertension and an increased mortality risk in the elderly.
The brain contains both grey and white matter. The grey is comprised of cell bodies and synapses and the white is composed of white bundles and their tails (axons), which connect regions of the brain to one another.
Shumei Li, a radiologist, and her team from Number 2 Provincial People’s Hospital in China conducted a study comparing 23 severe insomniacs and 30 people with normal sleeping patterns. The team used diffusion tensor imagining, which is a technique that lights up the white matter circuitry.
Regions in the right hemisphere that support learning, emotion, smell and memory were less well connected in the people suffering with insomnia when compared with the healthy sleepers. The team concluded that this was due to loss of the fatty myelin sheath. This surrounds the axons in the white matter and assists the transmission of signals. Poor connections were also identified in the white matter of the thalamus, the region of the brain responsible for regulation of consciousness, alertness and sleep.
It has been suggested by a study carried out in November that the loss of the myelin sheath could be down to smoking cigarettes. Max Wintermark, a radiologist from Sanford states that there could be other factors, “It’s not possible to say whether poor connections are the cause or the result of insomnia.”
However, the team who recently conducted the study has proposed a mechanism for the cause of insomnia. Wintermark continues to explain that this has brought us closer to understanding the cause and therefore finding a potential treatment for the disorder.