Impaired visual signals might contribute to schizophrenia symptoms

July 29, 2013

By observing the eye movements of schizophrenia patients while playing a simple video game, a University of British Columbia researcher has discovered a potential explanation for some of their symptoms, including difficulty with everyday tasks.

The research, published in a recent issue of the Journal of Neuroscience, shows that, compared to healthy controls, patients had a harder time tracking a moving dot on the computer monitor with their eyes and predicting its trajectory. But the impairment of their was not severe enough to explain the difference in their predictive performance, suggesting a breakdown in their ability to interpret what they saw.

Lead author Miriam Spering, an assistant professor of ophthalmology and visual sciences, says the patients were having trouble generating or using an "efference copy" – a signal sent from the eye movement system in the brain indicating how much, and in what direction, their eyes have moved. The efference copy helps validate visual information from the eyes.

"An impaired ability to generate or interpret efference copies means the brain cannot correct an incomplete perception," says Spering, who conducted the dot-tracking experiments as a postdoctoral fellow at New York University, and is now conducting similar studies at UBC. The brain might fill in the blanks by extrapolating from prior experience, contributing to , such as .

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 , such as walking along a crowded sidewalk.

"But just as a person might, through practice, improve their ability to predict the trajectory of a moving dot, a person might be able to improve their ability to generate or use that efference copy," Spering says. "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."

Explore further: Writing in cursive with your eyes only

Related Stories

Writing in cursive with your eyes only

July 26, 2012
A new technology described in the paper published online on July 26 in Current Biology might allow people who have almost completely lost the ability to move their arms or legs to communicate freely, by using their eyes to ...

Seeing movement: Why the world in our head stays still when we move our eyes

March 21, 2012
Scientists from Germany discovered new functions of brain regions that are responsible for seeing movement.

Barrow researchers unravel illusion

May 1, 2012
Barrow Neurological Institute researchers Jorge Otero-Millan, Stephen Macknik, and Susana Martinez-Conde share the recent cover of the Journal of Neuroscience in a compelling study into why illusions trick our brains. Barrow ...

More than just looking: Role of tiny eye movements explained

February 21, 2013
Have you ever wondered whether it's possible to look at two places at once? Because our eyes have a specialized central region with high visual acuity and good color vision, we must always focus on one spot at a time in order ...

Are people really staring at you?

April 9, 2013
(Medical Xpress)—People often think that other people are staring at them even when they aren't research led by the University of Sydney has found.

Why do age-related macular degeneration patients have trouble recognizing faces?

January 7, 2013
Abnormalities of eye movement and fixation may contribute to difficulty in perceiving and recognizing faces among older adults with age-related macular degeneration (AMD), suggests a study "Abnormal Fixation in Individuals ...

Recommended for you

The neural codes for body movements

July 21, 2017
A small patch of neurons in the brain can encode the movements of many body parts, according to researchers in the laboratory of Caltech's Richard Andersen, James G. Boswell Professor of Neuroscience, Tianqiao and Chrissy ...

Faulty support cells disrupt communication in brains of people with schizophrenia

July 20, 2017
New research has identified the culprit behind the wiring problems in the brains of people with schizophrenia. When researchers transplanted human brain cells generated from individuals diagnosed with childhood-onset schizophrenia ...

Scientists reveal how patterns of brain activity direct specific body movements

July 20, 2017
New research by Columbia scientists offers fresh insight into how the brain tells the body to move, from simple behaviors like walking, to trained movements that may take years to master. The discovery in mice advances knowledge ...

Scientists discover combined sensory map for heat, humidity in fly brain

July 20, 2017
Northwestern University neuroscientists now can visualize how fruit flies sense and process humidity and temperature together through a "sensory map" within their brains, according to new research.

Team traces masculinization in mice to estrogen receptor in inhibitory neurons

July 20, 2017
Researchers at Cold Spring Harbor Laboratory (CSHL) have opened a black box in the brain whose contents explain one of the remarkable yet mysterious facts of life.

Speech language therapy delivered through the Internet leads to similar improvements as in-person treatment

July 20, 2017
Telerehabilitation helps healthcare professionals reach more patients in need, but some worry it doesn't offer the same quality of care as in-person treatment. This isn't the case, according to recent research by Baycrest.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.