system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel] How does a symbiote turn people towards a more aggressive mindset?

Altering brain chemistry?  Being a little devil whispering in one's ear?  Sheer force of will?  Charm?
gpt
I'd like to believe that Venom and his ilk bind to their hosts spinal cord and use this as a neural connection to the brain.  They use their connection to the spinal cord to mildly stimulate the sympathetic nervous system at a constant rate. They also direct the endocrine system to release testosterone and glucocorticoids.  This gives the host a predisposition towards violence and a constant adrenaline rush.  This state of mind will lead them to test their new abilities and generally leads to a violent disposition.  It also gives mild withdrawal symptoms upon seperation from the symbiote. 
  
  
This theory is not based on evidence.