More than three years ago I wrote about a study that found insomnia sufferers were worse at reading emotions than healthy sleepers.
A new study may provide some additional clues - it found that insomnia may actually damage the way our brains regulate and process our emotions.
This is perhaps unsurprising when you consider that insomnia is a well known risk factor for emotional conditions such as depression.
The study in question involved two groups of participants - one group was made up of individuals suffering from chronic primary insomnia and the other group was made up of good sleepers.
Each group was shown images that depicted negative and neutral emotional content.
On the first viewing, each group was told to look at the images without trying to control their emotional response.
The second time the groups viewed the images, they were told to try to change their emotional response to the images by attempting to decrease their negative emotional response (this goes by the fancy term of cognitive reappraisal).
Researchers found that a cluster of neurons responsible for processing and regulation emotion (the amygdala) was significantly more active in insomnia sufferers compared to the healthy sleepers when they were trying to interpret the images less negatively.
This is a significant finding since previous research found that cognitive reappraisal decreased amygdala activity. Since these results found the exact opposite, it may mean that insomnia damages the way the brain processes negative emotions when it is deprived of sleep.
So next time your insomnia leaves you feeling especially cranky and impatient, don't blame yourself - blame your amygdala!