What is the definition or description of: abrupt personality change?

Personality change: An example of this might be when intoxicated with alcohol, some of the sweetest tempered people can become mean and violent drunks.

Change brought on by: physical factors such as some types of seizures. For example, some children have episodes of explosive and violent behavior while being absolutely fine in between these. Parents will say that they can tell by the look on the child’s face that one is about to happen. There will be a change in facial expression, body language, even speech pragmatics (the way one turns a phrase) and a nice child will become verbally very cruel, menacing, unable to be reasoned with, violent, will say things in a way that is atypical for their usual personality and are intended to be hurtful in the most cruel way, become extraordinarily strong so that even two adults cannot restrain them. After the episode ends, the child will seem better that usual, very loving and kind, unaware of what has just happened and unable to comprehend that he has done the things described. The normal personality is back. This phenomenon has an octal or seizure like quality to it in it’s abrupt onset and post episode relief of all symptoms (interictal calm). It is also very responsive to seizure medication.