Hey office loudmouth: introverts may be silently judging you, right now.

new study suggests introverts are highly critical of their extroverted co-workers and will judge their work more harshly than that of their fellow introverts – even if that work is exactly the same. Introverts were also less likely to endorse their extroverted colleagues for promotions or bonuses, according to joint research from Oregon State University, the University of Florida and the University of Notre Dame.

The findings suggest highly extroverted employees may want to tone it down around introverted bosses and colleagues, lest they torpedo their careers.

“We found that introverted employees are especially sensitive to their co-workers’ interpersonal traits, in particular extraversion and disagreeableness,” study co-author and assistant professor at Oregon State University Keith Leavitt said in a release. “They make judgments and evaluate performance of others with those traits in mind.”

The findings, to be published in the Academy of Management Journal, stem from two studies. In the first, 178 MBA students got into groups of four or five for the semester. Halfway through they were asked to fill out personality questionnaires about themselves, as well as performance evaluations of their team members. Introverted pupils gave lower ratings to their extroverted peers than to other introverts. The outgoing students rated their colleagues too: Their evaluations didn’t align with any particular personality trait.

The second experiment involved 143 management students playing a 10-minute online game alongside three teammates. The researchers manipulated one of the team member’s comments and profiles in the game to highlight either introversion or extraversion. But there was no actual difference in that member’s performance. Participants then had to evaluate their teammates and recommend them for promotions or bonuses. Introverts issued weaker evaluations and doled out smaller bonuses to the supposedly extroverted players. As in the first study, extroverted respondents evaluated others on the basis of merit, not what they perceived to be their personality type.

The researchers recommend extroverts bring it down a notch in the office, especially in their interactions with introverted colleagues and employers who may be exhausted by all that effusive energy. Prof. Leavitt called it a “dimmer switch.”

Susan Cain addressed office dynamics in her 2012 bestseller Quiet: The Power of Introverts in a World That Can’t Stop Talkingwhich turned introversion into an international conversation.

Cain, a former corporate lawyer, argued that the world rewards extroverts to its own disadvantage, as introverts make up about half the population and have much to offer, if only less noisily. In Quiet, she describes a “two-tier class system when it comes to personality style,” with extroverts generally coming out on top.

At the office, extroverts are the risk takers and introverts the prudent thinkers, she observes. Extroverts work quickly and squawk about their achievements, yearning for status. Introverts take a back seat, working slowly but deliberately – they tend to overprepare but end up producing better ideas. They’re bad at the kind of small talk that gets people liked by the water cooler.

Cain advised managers to recognize the introverts on their team. They’re not necessarily going to be “jazzed up” about open concept office space, lunch birthday parties or boisterous team building exercises – what Prof. Leavitt called “forcing interaction among employees.” Cain recommended employers build “restorative niches” into the architecture of offices or negotiate flex time with their more ruminative staff members.

Her book and the latest research suggest that we ignore – or yack over – the introvert at our peril: A quiet type may just be your next boss.

The Globe and Mail
Published Friday, Dec. 19 2014, 11:45 AM EST
Last updated Friday, Dec. 19 2014, 12:02 PM EST