Why are we irritable when we don't sleep?

Lack of sleep or sleep deprivation, can cause a depletion of a neurotransmitter called Serotonin. Serotonin is one of the many calming hormones, and it allows us to keep our cool during stressful situations. Without enough Serotonin we may become irritable. In addition, sleep deprivation can lead to elevated levels of Cortisol, which is a hormone that can lead to increased stress. Thus if we have fewer calm feelings and more stress feelings we may become irritable.

Researchers say that the brain's prefrontal cortex, which helps keep emotions in check, doesn't send out inhibiting signals as well when we're sleep-deprived. So we're moodier as a result.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.