However, some psychiatric and neurological disorders lead to a marked increase in left-right confusion. Studying patients with these disorders may help in understanding why left-right confusion occurs, but so far, there has been no systematic investigation about which exact diseases and disorders are linked to an increase in left-right confusion. People with dyslexia also show an increase in left-right confusion, with about twice as many people with dyslexia reporting problems with left-right confusion as people without dyslexia. For other investigated disorders, such as schizophrenia or prosopagnosia, the results on left-right confusion were less clear than for those three groups. One reason for left-right confusion is that the functioning of the parietal lobe, which is central for spatial abilities, is impaired.