New study claims sleep deprivation can result in anger; here's the science behind why we feel angry and frustrated

Feeling angry, from time to time, is completely normal. Anger is an emotion that may be expressed in response to a disagreement, injustice, threat or many other triggers. According to Dr RJR Blair from the Institute of Cognitive Neuroscience, London, “Anger is a response to a perceived threat to oneself or to another. It is a response to frustration”. But there can be other factors at play behind feeling angry too - such as sleep. In a recent study published in the journal Sleep, scientists found that insufficient sleep can result in increased anger. Sleep deprivation could be the reason behind your anger Scientists of the American Academy of Sleep Medicine conducted a study in which they included 147 people who were either asked to maintain their regular sleep cycle or to reduce their sleeping time at home by about five hours over two nights. After the two days, the participants were exposed to irritating noise. The results of the experiment showed that people who slept well were able to adapt to the noise and reported less anger as compared to those who were sleep-deprived. People who reduced their sleeping time felt high and increased anger after listening to the irritating noise. The scientists concluded that lack of sleep weakens the ability to adapt to frustrating situations resulting in increased incidences of getting angry. Why do we feel angry: The neuroscience behind anger We all have our anger triggers. While some of us get angry when someone disobeys us, others may get angry for not having their favourite dish for dinner. Whatever the reason may be, you would be able to recall your breath getting faster, heart-pounding hard in your chest and your face going all hot and red. But why do we get angry? Scientists have an explanation which suggests that it all starts in the brain. The outer portion of the brain is known as the cerebral cortex which helps in applying logic and making decisions. However, the emotional centre of the brain is known as the limbic system which is located lower in the brain. It has been noticed that when a person gets angry, their limbic part of the brain gets more activated than the cortex. The hijacking of the amygdala The limbic system consists of amygdala, which looks like two almond-shaped clusters of nerves and is situated in the temporal lobes of the brain. Amygdala manages the emotional responses, memories, decision making and fight or flight responses, which get activated during a dangerous situation. Whenever an anger trigger is sent to the brain, the amygdala decides whether to send that data to the limbic or cortex area of the brain. If the incoming data triggers the emotional part, the amygdala overrides the cortex and sends the data directly to the limbic system. Due to this overriding event, the amygdala goes into action without using judgement, power of thinking or evaluation. This reactive event is also known as an amygdala hijacking. When the amygdala gets hijacked, the body releases epinephrine and norepinephrine, which prepare the person for the fight or flight response. It has been noticed that this hormonal flush lasts for several minutes during which the person stays out of control and this is the time when the person shows anger either verbally or physically. Once this phase passes, the person starts regretting their actions as their thinking part of the brain goes into action. In some people, there can be a release of an additional longer-lasting hormone which may keep people feeling angry for several hours to several days. For more information, read our article on How to control anger. Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.