How the Brain Controls Sensory Overload

In our brain fearful emotions are controlled by a tiny organ called the amygdala.  It is often referred to as the Anger Management Center.

 

 

Fig. 1.  Location of the Amygdala in the Brain.  The tiny amygdala is located on top of the spinal cord. Nerve signals from the eyes, ears and skin are transmitted to the amygdala where they are analyzed for potential danger.


   

  
   
Here, sensory inputs such a sights, sounds and touch are analyzed for their "danger quotient" and appropriate responses are mounted to escape any perceived danger. 

Unless the reasoning part of the brain instructs the amygdala that the sensation is not dangerous, the amygdala automatically triggers a "fight or flight" response. 

We have all experienced the effects of being startled and scared. It's an adrenalin rush. In an instant we are on high alert. We panic and are overpowered with an intense urge to fight or run. At the instant we perceive danger, we are thrust into a state of Acute Sensory Overload.

The image below shows how the amygdala is activated by fear and environmental occurrences.

activation of the amygdala

  

    When we see a smile, the amydala is quiet. When we see a frown, it is activated. The level of activity is determined by the intensity of the threat. In the example shown here, smile = low activity (yellow line), frown = higher activity (blue line), fright = highest activity of the amygdala (red line).

    When the perceived danger passes, we slowly get back into control as normal reason prevails over emotion. This happens when the brain has analyzed the situation and has determined that all is OK.

    Then the "reasoning" part of the brain sends a signal to the amygdala to shut down. The shut down signals are two inhibitory neurotransmitters called Serotonin and Glycine.

    If we have sufficient quantities of serotonin and glycine available in our brain, the shut down is rapid and complete. If we do not have enough, the shut down is slow and partial. In this case, the continual sensations we receive from the outside world are never completely inhibited, and we are left in a perpetual state of low level "fight or flight".

    It is not as intense as a full-blown panic attack, but it is constantly there. In this case we remain in a perpetual state of anxiety. We are experiencing Chronic Sensory Overload. Persons with low levels of brain serotonin and glycine are constantly fighting to get back to normal. That is the case with those with autism, ADD, chronic anxiety, nervousness and uncontrollable anger.


To find out how N-MET can help with Sensory Overload please read the article under Learn & Explore titled, "Defeating Sensory Overload."