Schizophrenia and the ability to track moving objects


Schizophrenia may need to include impaired eye movements as part of its basic symptomology.

According to research from the University of British Columbia, scientists there tracked the eye movements of patients with schizophrenia while they played video games and found distinct characteristics.

Only half of schizophrenics receiving appropriate care

Schizophrenia is a mental illness which generally surfaces in adolescence or early adulthood. Patients may experience loss of personality, delusions, agitation, confusion, social withdrawal, psychosis and bizarre behavior.

About 24 million people worldwide are affected by the disorder. The World Health Organization believes that only half of those are receiving the appropriate care.

Unable to track the dot

For their research, scientists asked patients to track a small dot that appeared on a computer screen and predict whether or not it would hit or miss a vertical line. The patients’ eye movements were tracked by infrared camera equipment.

Researchers found that the patients with schizophrenia had a harder time tracking the moving dot and predicting its movements compared to healthy patients who did not have the mental disorder. Still, the impairment was not bad enough to explain the difference in their predictive performance. This suggests there is a “broken connection” in the ability of a schizophrenic person to interpret what they are seeing.

Impairment with the 'efference copy'

There may be a difficulty in the schizophrenic’s ability to generate an “efference copy.” This is a message that the eye movement area of the brain sends to determine direction by sensing how the eye has moved.

“An impaired ability to generate or interpret efference copies means the brain cannot correct an incomplete perception,” explained Miriam Spering, assistant professor of ophthalmology and visual sciences at the university. “The brain might fill in the blanks by extrapolating from prior experience, contributing to psychotic symptoms, such as hallucinations.”

Practice might improve the skill

“My vision would be a mobile device that patients could use to practice that skill, so they could more easily do common tasks that involve motion perception, such as walking along a crowded sidewalk,” said Spering.

Source: MedicalNewsToday, Journal of NeuroScience


The information provided on the is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her health professional. This information is solely for informational and educational purposes. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Neither the owners or employees of nor the author(s) of site content take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading this site. Always speak with your primary health care provider before engaging in any form of self treatment. Please see our Legal Statement for further information.

PsyWeb Poll

Are you currently taking or have you ever been prescribed anti-depressants?
Total votes: 3979