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Well, Organic brain syndrome consists of disorders such as Dementia
and Delirium , both of which can occur as a result of head injury or insult to the brain , and so in Organc brain syndrome (OBS ) , one may have loss of short term memory (retrograde memory) as seen specifically in dementia , and in your case dementia secondary to head trauma .
However , Personality disorder is a different entity , and it is not consistent with OBS , WHATSOEVER , however , this does not rule out the fact that the two different entities cannot occur in the same person, but whenever such a condition may happen , personality disorder needs to be present in the person right from the start , as in right from his younger days , and the typical personality would get stuck to that person life long.
While , OBS , is developed later in life , and is predisposed by specific reasons such as advancing age , stroke
, neurodevelopmental disorders , head trauma, inflammation, infection, etc for DEMENTIA and Alcohol intoxication, alcohol withdrawl , Infection , inflammation of meninges, head trauma and many other causes.
So, you see Personality disorder and OBS are two different conditions with different clinical picture , have no consistency with each other whatsoever , but by shear coincidence can occur together in a person , but that too a Personality disorder occurring first AND OBS DEVELOPING LATER IN life , due to some predisposing condition./ cause.
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