Lefties More Likely to Suffer Schizophrenia
Lefties are more likely to suffer from psychotic disorders than mood disorders, a new study suggests.
Scientists have long researched the connections between hand dominance and aspects of the human brain, and latest finding links left-handedness to higher rates of mental illness like schizophrenia and schizoaffective disorder.
"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," researchers wrote in the study.
The study involved 107 patients from a public psychiatric clinic seeking treatment in an urban, low-income community. Researchers determined the frequency of left-handedness within the group of patients identified with different types of mental disorders.
The findings revealed that 11 percent of people diagnosed with mood disorders such as depression and bipolar disorder were left-handed, which is similar to the rate in the general population. However, 40 percent of patients with schizophrenia or schizoaffective disorder were left-handed.
Researchers explain that brain lateralization, scholastic achievement and race may all be contributing factors to the higher schizophrenia rates in left handedness.
"Our own data showed that whites with psychotic illness were more likely to be left-handed than black patients," researchers wrote. "Even after controlling for this, however, a large difference between psychotic and mood disorder patients remained."