If you're sleep deprived, you may lose your temper over small things. Aside from negatively affecting your mood, emotional reactivity can make you feel physically tired and drained.
Researchers are still trying to understand the connection between sleep and emotion, but current data suggest that sleep deprivation affects the complex emotional centers of the brain.
Studies have determined that sleep deprivation increases activity in the amygdala, your brain's "emotional rapid-response center." The amygdala controls many of your immediate emotional reactions and when you don't get enough sleep, it goes into overdrive, which makes you more emotionally reactive to situations.
It's worth noting that a lack of sleep makes you "more reactive across the whole spectrum of emotions," both positive and negative.
When the amygdala is in overdrive, sleep deprivation also blocks the communication between the amygdala and the prefrontal cortex, another part of the brain linked to emotional regulation.
The prefrontal cortex is involved in many functions, and one category of cognition often linked to this section of the brain is executive functions. Generally, executive functions focus on controlling short-sighted, reflexive behaviors to complete tasks like "planning, decision-making, problem-solving, self-control, and acting with long-term goals in mind."
Lacking sleep damages the way prefrontal cortex functions. You may become more impulsive and less thoughtful in your emotional responses. (Related: How sleep deprivation affects your physical and mental health.)
Sleep deprivation is linked to a more negative outlook. Poor sleep quality can make you focus on the negative, which increases "repetitive negative thinking."
According to psychologists, repetitive negative thinking occurs when the mind is stuck in a negative place and goes over the same frustrated thoughts repeatedly. Since repetitive negative thoughts are difficult to control, they can significantly affect how you feel and function. They’re also associated with the development of mood disorders like depression and anxiety.
In a study conducted by researchers from the University of California, Berkeley (UC Berkeley), findings revealed that sleep deprivation increases your tendency to worry about the future. Experts call this form of worry "anticipatory anxiety."
Sleep deprivation exacerbates anxiety and contributes to anxiety disorders. As a result, you may have a harder time falling asleep when you're anxious.
In a different study, UC Berkeley researchers discovered that sleep deprivation can diminish your personal relationships. Even if only one person in a relationship is sleep-deprived (and cranky), both partners may have a tendency "to feel a diminished sense of gratitude toward each other."
Sleep deprivation also affects your capacity for empathy, an emotional skill that is crucial for healthy relationships. Empathy refers to your ability to understand someone else's experiences, feelings, and thoughts.
When you don't get enough sleep, important aspects of your emotional intelligence, such as self-awareness and empathy, are impaired. This can negatively affect your work and personal relationships, which should be treated more carefully.
To maintain your physical, mental, and emotional well-being, get enough sleep every night.