Why would I be asked to count backwards by 3, from 100 in a psychological test? On an initial mental health consultation with a psychiatric nurse practitioner, I was asked, among many other odd questions, to count backwards by three. 100, 97, 94...

This was quite a number of years ago and I've often wondered what the purpose behind this question was, and what some of the the other curious questions accomplish. I have my suspicions, but I'm not certain.

What's a baker's dozen?
What do you think "people in glass houses shouldn't throw stones" means?

Thanks
Why would I be asked to count backwards by 3, from 100 in a psychological test?


This is to test your cognitive reasoning abilities, particularly your ability to concentrate and recall serial information. Similar tests are administered to injured sports players to ensure that they do not have a concussion. 1


  What's a baker's dozen? What do you think "people in glass houses shouldn't throw stones" means?


This is used to test your ability to handle abstraction in language. One symptom of autism is an inability to understand metaphorical significance of language in non-literal terms. While the average adult would understand that the second sentence is a proverb (and can infer its meaning even without context), an autistic adult might interpret the sentence literally, i.e. 'people in glass houses shouldn't throw stones because their parents might get mad at them.'