If you find some people more charismatic because they are quick to respond when asked a question, it is because charisma may rely on quick thinking.
The findings showed that people who were able to respond more quickly to general knowledge questions and visual tasks were perceived as more charismatic by their friends -- independently of IQ and other personality traits.
"Social intelligence is more than just knowing the right thing to do," said psychological scientist William von Hippel from University of Queensland in Australia.
Social intelligence also requires an ability to execute, and the quickness of our mind is an important component of that ability.
Von Hippel and colleagues were intrigued by why some people exude more charisma than others, and wanted to understand the factors that might drive these differences.
To investigate whether mental speed might contribute to charisma, the researchers conducted two studies with a combined total of 417 participants.
Participants in the studies completed established measures of intelligence and personality.
To gauge charisma, the researchers asked the participants' friends to rate how "charismatic", "funny" and "quick-witted" they were.
To measure mental speed, participants then answered 30 common-knowledge questions as quickly as possible.
In the second study, they also completed timed tasks that required them to locate a dot or identify a pattern as quickly as possible.
The results showed that participants who were faster on the mental speed tasks were perceived as more charismatic.
This association remained after other factors, such as general intelligence and personality, were taken into account.
"We found that how smart people were was less important than how quick they were," von Hippel added.
So knowing the right answer to a tough question appears to be less important than being able to consider a large number of social responses in a brief window of time.
The researchers speculate that mental speed may also make it easier to quickly mask an inappropriate reaction and make humorous associations on the spot.
Contrary to the researchers' predictions, mental speed did not predict other social skills, such as being adept at handling conflict or interpreting others' feelings.
These studies suggest that social intelligence depends on more than knowing specific social rules or having certain social abilities, like the ability to read people's facial expressions.
The research was published in the journal Psychological Science.