Understanding Irritability: A Common Human Experience
Irritability – that sudden rush of anger over seemingly minor things – is a universal human experience that many of us know all too well. Whether it’s triggered by a colleague’s annoying email, being stuck in traffic when running late, or finding dirty dishes in the sink, our disproportionate reactions can lead to snapping at loved ones or other impulsive behaviors. According to a 2024 survey of nearly 43,000 U.S. adults, irritability is remarkably common, with participants averaging 13.6 on a scale from 5 (never irritable) to 30 (highly irritable all the time).
While occasional irritability is normal, it can become problematic when it causes significant distress or interferes with daily functioning. Dr. Roy Perlis, a psychiatrist at Massachusetts General Hospital who conducted the survey, notes that patients complain about being irritable as often as they report depression or anxiety. Yet despite its prevalence, irritability in adults has long been overlooked in research, which has traditionally focused on children and adolescents where it manifests as explosive tantrums. Scientists are now turning their attention to understanding what makes adults irritable and how to manage this emotional state effectively.
The biological roots of irritability run deep and extend beyond humans. Researchers study irritability in mice by withholding expected rewards, which causes the rodents to press harder and longer on levers – similar to how humans might repeatedly jab at an elevator button when it’s slow to arrive. This cross-species similarity suggests irritability may have evolutionary benefits, potentially helping animals obtain what they need or want. However, it becomes concerning when it leads to persistent distress or dysfunction, such as when someone frequently starts arguments with coworkers or regularly regrets their emotional outbursts. For women with premenstrual dysphoric disorder (PMDD), extreme irritability before menstruation can cause significant relationship problems and make it difficult to focus on work or other responsibilities.
Brain imaging studies provide clues about the neural basis of irritability. Research with children and teenagers shows that highly irritable individuals process threats and rewards differently than their even-tempered peers. When frustrated, their brains show heightened activity in the striatum (a key reward-processing region) and unusual responses in brain areas responsible for executing tasks, which explains why it’s harder for irritable people to focus when frustrated. The amygdala – the brain’s threat-processing center – also shows unusual activity patterns. While research on adult brains is still emerging, evidence suggests the same neural circuits are involved. According to Dr. Manish Jha of UT Southwestern Medical Center, “What we see is that the brain circuits related to reward and threat are implicated.”
Irritability often coexists with mental health conditions like depression and anxiety, possibly because they share genetic factors or arise from similar dysfunctions in threat and reward processing systems. Notably, frequent irritability is a risk factor for developing suicidal thoughts, making it an important marker for mental health professionals to monitor. It’s also common in conditions like ADHD, bipolar disorder, and during hormonal fluctuations like menopause. People who have experienced trauma may get “stuck” in feelings of anger, including irritability. However, Dr. Perlis emphasizes that extreme irritability doesn’t always signal a mental health condition – sometimes it simply reflects temperament. External factors like illness, stress, sleep deprivation, hunger, and excessive social media use can also trigger or worsen irritability.
Scientists are exploring various treatments for debilitating levels of irritability. Some researchers are investigating oxytocin nasal sprays, while others like Dr. Tseng are testing transcranial magnetic stimulation to normalize activity in reward-processing brain regions. For now, Dr. Jha recommends that people with severe irritability seek a full psychiatric evaluation to identify and treat any underlying mental health conditions. Studies show that antidepressants can reduce irritability symptoms in depressed adults and women with PMDD. Cognitive behavioral therapy helps by teaching people to recognize early signs of anger and develop constructive management strategies.
A promising approach involves self-monitoring. In a 2025 study, researchers gave anger-prone trauma survivors a smartphone app that prompted them to evaluate their anger levels throughout the day, along with a wearable device to track physiological indicators of stress. This self-reflection helped participants recognize impending anger episodes and take calming actions through breathing techniques, removing themselves from triggering situations, or reframing their thoughts about others’ behaviors. Anyone prone to irritability can benefit from regularly checking their mental and physical state for signs of increasing anger – tension in muscles, gritted teeth, chest tightness – and being aware of external factors that might exacerbate irritation. As Dr. Perlis concludes, “Being irritable is not a character flaw. It is something people can learn to manage, but sometimes, some people will need additional help to learn to manage it.”
