A new study now suggests that less than eight hours sleep is linked to anxiety and depression.
According to the study, insomniacs are less able to overcome negative thoughts than those who are able to get sufficient shut eye which also reduces people's ability to disengage from negative emotions, the research adds.
According to study author Professor Meredith Coles from Binghamton University some people have tendencies to have thoughts get stuck in their heads, and their elevated negative thinking makes it difficult for them to disengage with the negative stimuli.
Up to 50 per cent of people in US have difficulty falling or staying asleep. Anxiety and depression affect around 40 and 16 million adults, respectively, every year in the US.
Researchers analysed adults with 'repeated negative thinking' (RNT) and the results reveal getting insufficient sleep causes people to spend more time looking at emotionally-negative images.
Insomnia also results in sufferers being unable to disengage from the negative pictures they view.
The findings were published in the Journal of Behavior Therapy and Experimental Psychiatry.
