Visual Contrast Sensitivity Testing to Check for Biotoxins

I first became aware of VCS testing when I was dealing with understanding and treating mold.  Dr Shoemaker from Pokomoke, MD is known for his work in this field.  It also is very helpful in helping to understand if you are affected by biotoxins.  First lets understadn what a biotin is

Biotoxins also directly affect nerve cell function, a poisonous substance produced by a living organism.Biotoxins are substances which are both toxic and have a biological origin.