New York, Nov 18 (IANS): A computer brain training exercise designed to improve the speed and accuracy of visual attention can help seniors reduce risk of dementia by nearly a third, suggest results of a 10-year study.

This exercise is known as "speed of processing training", "useful field of view training", or "UFOV training.

"Speed of processing training resulted in decreased risk of dementia across the 10-year period of, on average, 29 per cent as compared to the control," said lead study author Jerri Edwards from University of South Florida in the US.

"When we examined the dose-response, we found that those who trained more received more protective benefit," Edwards added.

The study, published in the journal Alzheimer's & Dementia: Translational Research & Clinical Interventions, enrolled 2,802 healthy older adults in the US and followed them as they aged from an average of 74 to 84 years.

Participants were divided into a control group or one of three intervention arms using different types of cognitive training.

One group received instruction on memory strategies and another group received instruction on reasoning strategies. The third group received individualised computerised speed of processing training.

Researchers found no significant difference in risk of dementia for the strategy-based memory or reasoning training groups, as compared to the control group.

However, as compared to the control group, the computerised speed training group showed significantly less risk of dementia -- averaging a 29 per cent risk reduction.

When reviewing the impact of each computerised speed training session completed, researchers found those who completed more sessions had lower risk.

The computerised speed training task was designed to improve the speed and accuracy of visual attention, including both divided and selective attention exercises.

The exercise was developed by Karlene Ball of the University of Alabama Birmingham and Dan Roenker of Western Kentucky University - both in the US.