A new study has found that left handedness is more common in people suffering from mental disorders such as Schizophrenia than in general population.
About ninety percent of people are right handed, but science hasn't been able to explain why. For centuries left handedness was seen as a sign of evil.
Lefties make up 20 percent of Schizophrenic patients despite accounting for just ten percent of the overall population, according to a report by the Wall Street Journal. A recent study had found that left handers are at a higher risk of developing mental disorders.
The small study was based on data from 107 people who were being treated for psychiatric problems.
Researchers found that about 40 percent people suffering from Schizophrenia were left-handed.
"Our results show a strikingly higher prevalence of left-handedness among patients presenting with psychotic disorders such as schizophrenia and schizoaffective disorder, compared to patients presenting for mood symptoms such as depression or bipolar disorder," wrote the authors.
Race, brain lateralization or socio-economic factors might explain the link between left handedness and Schizophrenia.
"Our own data showed that whites with psychotic illness were more likely to be left-handed than black patients," the authors explained, according to a news release. "Even after controlling for this, however, a large difference between psychotic and mood disorder patients remained."
The study, 'Left-Handedness Among a Community Sample of Psychiatric Outpatients Suffering From Mood and Psychotic Disorders,' is published in the journal SAGE Open.