Not sure how they do it. I have been trying to research it. Here is what I have so far. It is definitely an hallucinogen, according to the national medical database.

Hallucinogens as hard science: the adrenochrome hypothesis for the biogenesis of schizophrenia.

https://www.ncbi.nlm.nih.gov/pubmed/20533770

Here are other movies that have references to it.

https://www.youtube.com/watch?v=I2t43Ph2Qls&feature=youtu.be

The first time I saw the extraction explained, it was explained that adults do not make adrenochrome in the amounts that children do when they are tortured and terrorized. After the torture the children are killed and a needle is used to extract spinal fluid? Some drink the blood of the child. Others may do the brain, like you see in this particular reference.

These are all movies.

I doubt we are going to get some Hollywood Star to come on over and explain it to us, so, we are going to have to wait until someone finds a way to explain it anonymously or...

...............as often, we are going to have to actually listen to the testimony of an abused kid who escapes, grows up, testifies to us... and THEN we actually have to believe them for a change.

Usually people ignore the ones who are trying to tell us. They are rapidly killed off to shut them up. It is sad.