New research published in Science Magazine sheds new light on the impact of watching violent scenes in television shows, the news, and movies.
When you allow yourself, or a child, to watch violent media images, you change the functioning of the brain and shift it into survival mode also known as the fight or flight, and stress response.
In the first experiment, MRI equipment was used to monitor blood flow in the brains of 80 adult volunteers while they watched scenes featuring “extreme male-to-male aggressive behavior and violence in front of a crowd”. The researchers also took samples of the participants’ saliva to measure changes in stress hormones levels to see if there was a hormonal response to the violence.
In a second experiment, the researchers also used chemicals to block the production of certain stress hormones while the volunteers watched violent scenes to see how it affected the participants’ brains.
Researchers noticed that when participants watched violent images, networks of nerve cells started to rapidly reorganize themselves throughout the brain: the participants’ brain function was changing in response to what they were seeing on the screen. The volunteers’ attention was re-orientated, their perceptions were heightened, and their autonomic nervous system became highly active, all of which are indicative of the stress response.
What if you don’t get frightened by violent images?
Even if you tell yourself that the fighting you saw in a movie, news broadcast, or TV show didn’t scare you, the stress response, which is governed by your unconscious mind, works fast. It is an active part of everything you do and is works like a virus checker, running quietly in the background of your mind, always alert and checking for threats.
When you are engrossed in watching a TV show, movie, or news footage, your unconscious sees the violent images and doesn’t know they are on a screen; your unconscious believes you are right there in the action. Seeing others get hurt triggers our unconscious to want to fight or flee to avoid injury, pain, and the potential for death because it thinks that you may be the next target of the serial killer, soldier, or alien who is being violent. The fight or flight response results in the heightened perceptions, reoriented attention, and nervous system stimulation observed in the volunteers.
The wider implications of this research are that watching domestic violence between parents, being subjected to physical punishment, and seeing gory photographs in newspapers and online may also shift a child and adult into fight or flight (survival) mode.
Why would you, as an adult, continue to watch violence when you know that it makes you more stressed, changes your perceptions to the world towards it being unsafe place, and shifts your brain and physiology into fight or flight mode. People who are more stressed also have higher incidences of disease.
 Hermans, E. et al. (2011). Stress-related noradrenergic activity prompts large-scale neural network reconfiguration. Science, 334, 1151-1153.
 Zald, D. H. (2003). The human amgydala and the emotional evaluation of sensory stimuli. Brain Research Reviews, 41, 88-123.