Here’s why you get grumpy after a bad night’s sleepNovember 14th, 2007 - 2:43 am ICT by admin
“It’s almost as though, without sleep, the brain had reverted back to more primitive patterns of activity, in that it was unable to put emotional experiences into context and produce controlled, appropriate responses,” said Matthew Walker, director of UC Berkeley’s Sleep and Neuroimaging Laboratory and senior author of the study.
“Emotionally, you’re not on a level playing field,” he added.
Walker and his team found that the reason behind the phenomenon is the amygdala, the region of the brain that alerts the body to protect itself in times of danger.
Walker said that amygdala goes into overdrive on no sleep, consequently shuting down the prefrontal cortex, which commands logical reasoning, and thus preventing the release of chemicals needed to pacify the fight-or-flight reflex.
Using functioning Magnetic Resonance Imaging (fMRI), Walker and his team found that the amygdala, which is also a key to processing emotions, became hyperactive in response to negative visual stimuli - mutilated bodies, children with tumors and other gory images - in study participants who stayed awake for 35 hours straight. Conversely, brain scans of those who got a full night’s sleep in their own beds showed normal activity in the amygdala.
“The emotional centers of the brain were over 60 percent more reactive under conditions of sleep deprivation than in subjects who had obtained a normal night of sleep,” Walker said.he study included 26 healthy people who were assigned to either a normal sleep group or to a sleep deprivation group, where they were kept awake for 35 hours. Afterwards, functional magnetic resonance imaging (fMRI) was used to measure the participants’ brain activity. alker said that the study findings lay the groundwork for further investigation into the relationship between sleep and psychiatric illnesses.
“This is the first set of experiments that demonstrate that even healthy people’s brains mimic certain pathological psychiatric patterns when deprived of sleep. Before, it was difficult to separate out the effect of sleep versus the disease itself. Now we’re closer to being able to look into whether the person has a psychiatric disease or a sleep disorder,” he said.
The study is published in the Oct. 22 issue of the journal Current Biology. (ANI)
- Dreams help grapple inner turmoil - Nov 24, 2011
- Obesity linked to sleep loss and food choices - Jun 10, 2012
- Brain's crossed wires cause depression - Dec 09, 2011
- Brain wiring makes women anorexic or obese - May 15, 2012
- Sleepless nights can lead to euphoria, risky behaviour: Study - Mar 24, 2011
- Brain abnormalities cause antisocial behaviour and drug abuse in boys - Sep 24, 2010
- Brains of maltreated kids, combatants aware of dangers - Dec 06, 2011
- Recreational Ecstasy use linked to loss of brain efficiency - May 04, 2011
- Some people are born to be pessimistic: Study - Feb 08, 2011
- A broken heart 'hurts' just as much as intense physical pain - Mar 29, 2011
- Teens with severe antisocial behavior have smaller brain structures - Apr 01, 2011
- Dream content measured for first time - Oct 30, 2011
- Harsh parenting 'can impair kids' emotional development' - Sep 22, 2010
- Brain helps teens resist peer pressure - Mar 25, 2011
- Dogs pay close attention to human signals - May 06, 2012
Tags: amygdala, brain imaging, brain scans, conversely, emotional brain, emotional challenges, emotional experiences, gory images, logical reasoning, magnetic resonance imaging, matthew walker, mutilated bodies, neuroimaging laboratory, part of the brain, prefrontal cortex, sleep deprivation, sleep walker, stayed awake, uc berkeley, visual stimuli