A GENTLE CURRENT HELPS WHEN WORDS ARE HARD TO FIND

摘要

People with Alzheimer's disease got better at a word-recognition task after their brains were stimulated with an electric current. like transcranial magnetic stimulation or TMS (see main story), transcranial direct current stimulation (tDCS) aims to activate or inhibit areas of the brain by making it easier or harder for the brain cells to fire. While TMS involves holding a current-carrying coil over the subject's head, tDCS, which has previously shown promise in treating pain and depression (New Scientist, 5 April 2006, p 34), uses electrodes to send a current of 1 to 2 milliamps through the skull. In Alzheimer's, the temporoparietal areas of the brain, which are involved in memory and recognition, are known to be less active than in healthy people. So Alberto Priori at the University of Milan, Italy, and his colleagues used tDCS to stimulate these areas. They asked 10 people with mild to moderate Alzheimer's to perform a word-recognition and a visual-attention task, before and after receiving tDCS or a sham treatment.