in the other 40%, it can be caused by a head injury, injury during the birthing process, alcohol and drug abuse, aging or a metabolic or biochemical disturbance or imbalance.

kubantu abangama40%, sinokubangelwa kukwenzakala kwentloko, ukwenzakala ngexesha lokubeleka, ukusetyenziswa kakubi kotywala kunye neziyobisi, ukuguga okanye ukuphazamiseka okanye ukungalingani ekwakhekeni komzimba okanye iikhemikhali emzimbeni.
