Researchers at the University of Abertay in Dundee, Scotland, say that the lefties are more likely to feel anxiety, shyness or embarrassment about doing or saying what they want.
The team have found that lefties are likely to agree with statements like "I worry about making mistakes" and "Criticism or scolding hurts me quite a bit".
Study leader Dr Lynn Wright has attributed the characteristics to wiring differences between the brains of left- and right-handers.
"Left-handers are more likely to hesitate, whereas right-handers tend to jump in a bit more," the Daily Telegraph quoted Wright as saying.
"In left-handers, the right half of the brain is dominant, and it is this side that seems to control negative aspects of emotion.
"In right-handers, the left brain dominates," she added.
During the study, the participants were given a behavioural test that assesses personal restraint and impulsiveness.
The findings have been published in the journal Personality and Individual Differences.