Sometimes it doesn’t take much for us to become annoyed, or say, mildly infuriated; something as simple as uneven or unmatching items or gaps in places they shouldn’t be can make us noticeably irritated. The answer to why that happens seemingly lies in the way our brain is wired.

“In said examples, networks in the anterior cingulate cortex and connected regions activate when our expectations are violated, when we see or experience something different from what we expect,” Emeritus Professor of Psychology Joseph Hellige explained. “As simple as a gap when we didn’t expect one and as complicated as an insult when we expected praise. Registering a deviation from expectation is largely automatic.”

Dr. Philip Gable seconded the idea that said mildly infuriating things get on our nerves because we detect that something is not right or not what we expected. “It’s like when you make an error, but instead of you making the mistake, you detect the mistake in the world around you,” he explained. 

“Potentially, the person could perceive that there is a disconnect between what we think is involved, and how we expect things to be. The anterior cingulate cortex is involved in error detection and could be sending the ‘something is wrong’ signal. After that, it is likely how we think about the situation that causes us to hold on to it as negative or bad.”

Prof. Hellige continued to explain that whether we find certain things or occurrences annoying or pleasurable depends on numerous different brain networks. “For example, the insular cortex is activated when we experience something physically unpleasant, like biting into rancid meat, or psychologically unpleasant, like overhearing someone criticize us.”

According to the expert, the seemingly minor annoyances vary from person to person based on context and life experience. “One person’s annoyance can even be another’s pleasure. The dissonance in Stravinsky’s Rite of Spring might grate on my nerves but be beautiful to a more trained mind.”

Dr. Hellige explained that the level of how strongly a person feels about certain annoyances relates to relative levels of activation among brain areas, including those in the limbic system and prefrontal cortex. 

“The level of irritation also tends to increase when a person already feels stressed or is overly tired. Parents know this well; the never-ending questions from our three-year-old are a pleasure when we’re well-rested and unhurried, but after two nights of little sleep with a work project overdue, the same behavior becomes irritating.”

According to Dr. Gable, another factor that is likely to influence the extent to which a person finds something to be (mildly) infuriating is how much a certain situation violates their expectation that something is wrong. “It could be how significant the person sees the problem that enhances the irritation; oftentimes, not having control over the situation can cause it to be more irritating,” he pointed out.