Researchers in Sweden have said that thinking outside the box, creativity, may also be linked to mental illness.

Fredrik Ullen of Karolinska Institutet said in a statement, "We have studied the brain and the dopamine D2 receptors, and have shown that the dopamine system of healthy, highly creative people is similar to that found in people with schizophrenia."

Studies show dopamine receptor genes are linked to the capacity for divergent thought, Ullen said.

Published in the journal PLoS one, the study measured the creativity of healthy individuals using psychological tests to determine different solutions to a problem.

Ullen further said, "The study shows that highly creative people who did well on the divergent tests had a lower density of D2 receptors in the thalamus, a part of the brain that serves as a kind of relay center filtering information, than less creative people. Schizophrenics are also known to have low D2 density in this part of the brain, suggesting a cause of the link between mental illness and creativity."

Ullen also said that fewer D2 receptors in the thalamus probably means a lower degree of signal filtering, and thus a higher flow of information from the thalamus and this may be behind the ability of healthy highly creative people to see numerous uncommon connections to solve a problem and the bizarre associations found in the mentally ill. (With inputs from Agencies)