How do drugs produce hallucinations?
Even though research is lacking, some scientists believe that drugs such as LSD cause a malfunction of the “filtering mechanism” for stimuli coming into areas at the base of the brain, called the “reticular formation”. When this filtering mechanism (however it works) is blocked, all environmental stimuli entering the brain via sight, hearing, touch, smell, etc. are allowed to flood the brain, causing hallucinations (probably in the conscious cortex). This makes sense, but it is old information since not much new research has been performed on how hallucinating drugs produce their effects.
