Intelligence

   Intelligence requires a high degree of feedback. The mind has to be able to smoothly compare and check any ideas it creates and sort and connect them with other ideas.  That is why the disruption of feed back is so destructive.  In fact that is one of the principal modalities in torture.  The goal of torture is to deny the victim any chance of maintaining a feedback loop, destroying the individual's ability to adapt or maintain rational thought.  Disruptive environments can be equally damaging.  .  This includes abusive families with children.  The children are being tortured and fail to develop feedback.  As they mature they typically attempt to destroy feedback in others through activities such as bullying.  Their brains have developed a strong model of dysfunction and cannot adapt to function.  Neighborhoods with high levels of crime produce a similar results.
    Intelligence requires the brain to wander, matching and comparing concepts.  then it must take the better parts and compare them with knowledge and experience, that is the feed back loop.  Anything that disrupts it will reduce and individuals ability to learn and adapt.  Dealing with incoherence in daily life makes people stupid and apathetic.  This is the typical condition of people living under tyrannies.
    This is also why people react so strongly to incompetent and unnecessary rules, either form government or business.  People feel themselves being disrupted and react with anger.  There is no way to avoid the damage unless the management is corrected.