It is well known that there is a link between "criminal" (violent) behavior and prior trauma/adverse childhood experiences. It is similarly well known that trauma has an effect on brain development. There's plenty of research into how violent behavior is passed on between generations. It is also known that neuroplasticity and therapy allows for regrowth and new connections to form.

I think it's a grave mistake to try and frame brain damage as the cause, and not the result of (transgenerational) violence.