Patients who are partially blinded by a stroke can recover some vision by retraining their brains with vigorous eye exercises, a study showed.
- Strokes occur when the blood flow to the brain stops. They can be caused by a blood clot that blocks a blood vessel in the brain or by a blood vessel that breaks and bleeds in the brain, according to the National Institutes of Health.
- The patients who engaged in the exercises on a computer every day for nine to 18 months were able to improve their vision significantly, research reported in Journal of Neuroscience found.
- The findings show that doctors may finally have a way to help stroke victims regain some lost sight in addition to improving speech and movement, said the lead study author, Krystel Huxlin. More research is needed to confirm the findings, she said.
- Strokes each year afflict about 795,000 people in the U.S., according to the U.S. Centers for Disease Control and Prevention.
- The condition kills more than 143,000 people, making it the third-largest cause of death, behind heart disease and cancer, and the leading cause of serious, long-term disability in the U.S., according to the American Heart Association.
- Researchers studied seven people who had suffered a stroke that damaged the part of the brain known as the primary visual cortex.Five completed the study, while two were used as controls and didn’t receive the visual exercises.
- Those with damage to the primary visual cortex often can’t drive, read or do ordinary chores like shopping. The damage can cause blindness in one-quarter to half of the normal field of view, making any objects left or right of center appear gray or dark.
- The goal of the study was to see if the area of the brain that focuses on motion perception could be stimulated enough.
- Participants in the study stared at a small black square in the middle of a computer screen while every few seconds a group of about 100 small dots appeared on the screen somewhere in the area relevant to where the person’s vision was damaged.
- The patients’ brains initially couldn’t process that the dots were present, although their eyes were taking in the information.
- After daily exercises of 15 to 30 minutes once or twice a day, the patients’ brains began to process the information, allowing them to become aware of the dots, the authors said. The researchers then moved the dots further into the blind areas, to help improve sight even more.
- It can take up to two months to retrain the brain to see one part of the blind area.
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