The Amygdala indicator is based on the child psychology theories described in the book "Hjernesmart pedagogik" ISBN: 978-87-7160-177-0

It enables children to self-reflect on there mood and state of mind and indicate that to his or her surroundings without having to describe it with words (which can be harsh).

We have had great success with our 7 year old. Enabling her to reflect and handle the inner thunderstorm that can occur in us all.

The basics on how it works

white: you are happy but concentrated and not observant about anything else but what you are focusing on.
green: Happy and observant about people around you.
yellow (blue in my case): Something is bothering you or is making you scared. People around you can ask about it and help you.
red: You're Angry! or Scared! Shouting stage. People need to stear clear or talk you down.
black: Communication is not an option. Need to be alone and ride it out and calm down.

Printing this I used and Prusa MK3 with an MMU2 (this supports 5 filaments print at the same time)

The colored parts are .9 mm in height and you should be able to glue them in after but I havn't tried. There might be some post process.

The needle snaps in. It has a .2 mm tolerance. I have multiple variations of the needle but this one seems to work best for me.