Studies are showing that porn use is changing neural pathways, specifically the mesolimbic dopamine pathway , particularly in the amygdala.
Which is dominant in children and teens; it is responsible for spontaneous immature and anxiety driven actions, the hippocampus starts to take over during the teen years into the early 20s. It over rides the amygdala with rational thought.
FWIW: (very simply)
In sheep studies the hippocampus is negatively affected by hormone blockers. I found another paper once that showed that fresh air and exercise positively supported the development of the hippocampus in the teen years.
The amygdala can also become changed during long term stress and anxiety and is something to do with depression / anxiety; anxiety is a primal response.
A quick google on the implications of this:
*Amygdala
It is involved in the encoding and storage of memories that have a significant emotional component
People who damage their amygdala have difficulty learning emotional responses and interpreting expressed emotions.
We tend to be more likely to remember events that produce strong emotional reactions, than events that do not.
One reason: amygdala attaches emotional significance to information and stimulates the hippocampus to encode the explicit info regarding the event
Another reason: Norepinephrine 'tags memory of an event with important emotional details and strengthens its long term storage
(Increased levels of norepinephrine at amygdala during arousal communicates to hippocampus that details of the exxperience are significant- strengthen stroge by hippocampus)
The hippocampus is crucial for long-term memory formation (not all types), specifically:
forming or encoding new declarative explicit memories (semantic and episodic)
not directly involved in forming or retrieving implicit procedural memories
This role is called consolidation, where newly forming memories are strengthened to enable permanent storage*