'Brain-training' is becoming a big industry as people look to boost their cognition and stave off mental decline. However, a review of the research by academics at Brown University in the U.S. has found that there is little evidence to back up the claims for cognitive training. The review found only a very small number of trials that met its quality criteria and even these were limited in their methodologies and follow-up. The authors of the study said that brain-training gadgets could actually have a negative effect by costing people money, diverting their time from exercise which is proven to prevent Alzheimer's and by worrying otherwise well people who are unable to master the devices.
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