Teachers often weave separate threads of comedy and authority in their attempts to engage students, but a new study shows there can be negatives for teachers who poke too much fun at themselves.

Educators of all kinds must be careful not to point out too many of their foibles or risk losing the confidence of their class, the study says.

'The Relationship of Instructor Self-Disclosure, Nonverbal Immediacy, and Credibility to Student Incivility in the College Classroom,' was published this week in the National Communication Association's journal; Communication Education.

“Previous studies have shown that students respond to teacher body language, and that they are less likely to disrupt class if they feel engagement from the professor,” says the study's lead author, Ann Neville Miller, Ph.D., associate professor of human communication at the University of Central Florida.

“But trying to get on students’ level by referring to problems in your personal life or foolish things you've done in the past is probably going to make them lose respect.”

The report says teacher credibility is an important tool for maintaining control of a class, but it is very difficult to attain. The study says credibility is not earned by boring students nor by trying to assume a false intimacy with them.

Over 400 students were surveyed for the study, participants were asked for opinions of the instructors whose class they had last attended, and to numerically evaluate their professors on a scale between ‘stiff’ and ‘friendly’. Students were also asked how credible they found their teachers, and to indicate how often they engaged in behaviour such as texting, making disparaging remarks, or packing up books before class was over.

The researchers found that if students viewed an instructor as credible, the extent of their personal gestures made little difference to the student's feelings about the class, or its tendency to act in an uncivil way.

“It appears that instructors who start out revealing negative things about themselves may raise the quotient of incivility in the class. Tempting as it may be for instructors to attempt to warm up students by being transparent about their foibles and excesses, extensive negative self-disclosure should be engaged in with caution,” the authors said.

“In other words,” they said, “competence is a sine qua non - if it is not clear that an instructor is competent, students will accord him/her only limited credibility of any sort.”

The report is available through the paid-subscription journal’s online portal.