Researchers from the University of California, Berkeley, United States of America in a new study have found that the type of sleep most apt to calm and reset the anxious brain is deep sleep.
The report added that a sleepless night could trigger up to a 30 per cent rise in emotional stress levels.
According to sciencedaily.com, the researchers found that a deep sleep, also known as non-rapid eye movement slow-wave sleep, is a state in which neural oscillations become highly synchronised, and heart rates and blood pressure drop.
The senior author of the study, Prof. Matthew Walker, said, “We have identified a new function of a deep sleep, one that decreases anxiety overnight by reorganising connections in the brain. Deep sleep seems to be an anxiety inhibitor, so long as we get it every night.”
The study published in the journal, Nature Human Behaviour, provides one of the strongest neural links between sleep and anxiety to date.
The study’s lead author, Dr Eti Simon, said, “Our study strongly suggests that insufficient sleep amplifies levels of anxiety and, conversely, that deep sleep helps reduce such stress.”
The researchers used series of experiments using functional MRI and polysomnography, among other measures, to scan the brains of 18 young adults as they viewed emotionally stirring video clips after a full night of sleep, and again after a sleepless night.
They measured the anxiety levels following each session via a questionnaire known as the state-trait anxiety inventory.
“After a night of no sleep, brain scans showed a shutdown of the medial prefrontal cortex, which normally helps keep our anxiety in check, while the brain’s deeper emotional centres were overactive.”
“Without sleep, it is almost as if the brain is too heavy on the emotional accelerator pedal, without enough brake. After a full night of sleep, during which participants’ brain waves were measured via electrodes placed on their heads, the results showed their anxiety levels declined significantly, especially for those who experienced more slow-wave NREM sleep,” the researchers wrote.
The finding of the study according to the researchers showed that the amount and quality of sleep the participants got from one night to the next predicted how anxious they would feel the next day.
@ Punch Newspaper
