People may find it more difficult than usual to speak clearly when discussing topics that provoke anger or distress, according to a new study in the June issue of the APA journal Emotion (Vol. 5, No. 2).
Moreover, the effect increases in people with lower than average cognitive functioning.
To reach this finding, psychologist Deanna Barch, PhD, of Washington University in St. Louis, and colleagues assessed 35 psychiatrically healthy participants' cognitive function.
The researchers then asked the participants 10 open-ended questions, such as "Tell me about a recent trip you took in a car," as well as questions probing participants to recall particular emotional experiences. As participants spoke, the researchers Monitored their heart rate and skin conductance.
After the interviews, the researchers rated the participants' responses with the Communications Disorders Index, a measure that identifies reference errors--when a spoken word or phrase obscures the speaker's intended meaning.
They found that when participants discussed negative topics, like a death in the family or loss of a job, they had more reference errors in their speech, as well as higher skin conductance and an increased heart rate, than when they discussed positive or neutral topics. The researchers also found a significant correlation between participants' performance on the Stroop task, a measure of cognitive control, and reference errors. Barch says that negative arousal may be a primary mechanism behind the errors.
"Negative arousal may produce disorganized speech," she says, warning: "If you're really mad, then you shouldn't have an important conversation with your boss or spouse because you won't be able to speak as clearly as you would like."
In the future, Barch and her colleagues aim to expand the study to examine whether the same effects hold true for positive arousal. They also plan to test people with schizophrenia, who are known to experience unusually high instances of language disturbance when discussing negative topics.