Sudoku Induced Epileptic Seizure
The 25-year-old right-handed physical education student was buried in an avalanche during a skiing holiday, as a result of which his brain was deprived of oxygen for some 15 minutes. He then developed shock-like contractions of the muscles in his mouth when he tried to talk, and in his legs when he tried to walk. Several weeks later, while trying to solve Sudoku puzzles, he developed clonic seizures in his left arm. These produce repeated jerking movements, and are far rarer than tonic-clonic seizures, which are typically preceded by muscle stiffness, and cause loss of consciousness. In this case, the seizures stopped immediately when the patient stopped solving the Sudoku puzzle. He also experienced similar seizures when performing other visuo-spatial tasks, such as sorting random numbers into ascending order, but not when he read a book, wrote something down, or did calculations. The doctors used functional magnetic resonance imaging (fMRI) to scan the patient’s brain while he was solving a Sudoku puzzle, and found that the seizures were caused by abnormally high levels of activity in the right central parietal cortex, a part of the brain involved in processing visuo-spatial information. Diffusion tensor imaging (DTI) further revealed what appeared to be a complete loss of inhibitory fibres in the same part of the brain.
