Characteristics of strong Ni

[guac]

What are some characteristics you've noticed in people with Ni program (ILI, IEI), as well as external characteristics? Mannerisms, body language.. Is there anything that someone may do that makes you go "hm that sure does seem like Ni" ? Any general observations? be as detailed as you'd like
Is it typically harder harder or easier to pinpoint?

Since Ni and Si seem to be such externally invisible functions, at least at first, I'm wondering this. I can't change the title anymore, but could you also write what you think for Si as well? And how do they differ?

thanks~

EDIT: i'm looking for observable concrete things, not an abstract definition of Ni and Si and comparison, I've read plenty of those, thank you.