Lack of Sleep Causes Emotional Instability, Study Suggests

Sleepless nights have negative effects on one's brain.

A new research, which is published at the Journal of Neuroscience, revealed that sleep deprivation might affect the brain's ability to regulate emotion, leading to the person feeling grumpy or bad-tempered.

Medical News Today (MNT) has learned that the researchers have identified the "neurological mechanism" which is responsible for impairment of emotion regulation and anxiety. Thus, determining that lack of sleep affects a person's ability to regulate emotion and "allocate brain resources for cognitive processing."

In order to arrive at this conclusion, the researchers, led by Professor Talma Hendler of Tel Aviv University (TAU) in Israel, experimented on 18 adults who were given two rounds of test after having a proper sleep and another round of the two tests after staying awake for a whole night in the laboratory.

While answering the tests, the participants are also undergoing brain mapping through electroencephalogram (EEG) and/or functional magnetic resonance imaging (fMRI).

In the first test, the participants were tasked to identify the direction of a small yellow dot which is moved over "distracting images." These images were described to be "positively emotional" represented by a cat, "negatively emotional" represented by a mutilated body and "neutral" represented by a spoon.

From this, the researchers found that the participants, after an appropriate rest, were able to identify the movement of the yellow dot over the neutral images faster and more accurately than they were after a wakeful night where their results in the neutral and emotional image tests were poor.

Furthermore, the restless participants' "electrical brain responses," measured through EGG, did not also show a "highly different response" to the emotional images, thereby indicating a low level of "regulatory processing."

In the second test, the participants, while inside an fMRI scanner, were shown neutral and emotional images to distract them while performing a task that required their attention to press a key or button.

Assessing all activity levels of the brain through the test, the researchers found that sleep-deprived participants were distracted by all images both neutral and emotional while only the emotional images distracted the participants when properly rested.

"These results reveal that, without sleep, the mere recognition of what is an emotional and what is a neutral event is disrupted. We may experience similar emotional provocations from all incoming events, even neutral ones, and lose our ability to sort out more or less important information. This can lead to biased cognitive processing and poor judgment as well as anxiety," Prof. Hendler told Science Daily.

According to the Center for Disease Control and Prevention (CDC), insufficient sleep is a public health problem that affects more than a quarter of the US population. Moreover, it also stated that insufficient sleep is associated with diseases such as diabetes, hypertension and depression.