Jerome has always been an extravert. there is some evidence that people like jerome seek stimulation because their normal brain arousal is relatively low. for example, extraverts exhibit less activity in a frontal lobe area involved in inhibition.

The blank in the sentence above is behavior. It is because it most likely that happens that when the frontal lobe has less activity, it could cause the behavior inhibition to be involved for both of them go together or they are connected. These usually happens with the cause of the brain arousal in a low result which Jerome exhibits.

They create genetic variations