Link between blindness and schizophrenia

The results of a study conducted at the University of Western Australia found that not a single person with a diagnosis of congenital or early cortical blindness developed schizophrenia. The study looked at data from almost 500,000 people, all collected from WA health registers between 1980 and 2001.Professor Vera Morgan, lead author on the project, said the team’s research also found that no one with a diagnosis of congenital or early cortical blindness developed any other psychotic illness. This leads us to think there is a link that must be explored, Morgan told Insight.Morgan said that while the link between these results is not yet understood, the brain’s plasticity could play a part. It’s very difficult to say what the exact mechanism is but we think that the protective effect for schizophrenia is related to some kind of compensatory cortical reorganisation in the brain that’s happening in response to having congenital or early cortical blindness, she said. As a result, some functions that are impaired in schizophrenia may actually be enhanced in people with congenital or early cortical blindness. {{quote-A:R-W:400-I:2-Q:“Some functions that are impaired in schizophrenia may actually be enhanced in people with congenital or early cortical blindness” -who:Vera Morgan, UWA}}While the researchers do not yet know the exact mechanism behind the protective effect, Morgan said it appears to be related to neuroplasticity because it is only seen in blindness that is congenital or of very early onset.“Also, more specifically, we only see it in cortical blindness (blindness arising in the occipital cortex region of the brain) and not peripheral blindness arising in the globe of the eye itself,” she saidThe findings may lead to improvents for the treatment of mental illnesses. If researchers can identify and reproduce the mechanisms that cause this protective effect, earlier interventions to minimise or prevent the symptoms that lead to schizophrenia may be possible.Morgan said in the future it would be good to repeat the study using a larger database. “Most importantly, we also need to undertake clinical and related studies, to determine what the exact mechanisms involved in the protective effect are.”The research was published in the British Psychological Society Digest Report. More reading:Funding boost for research into curing child blindness