What determines the viewer scale with monoscopic 360 video?

Hi,
If any clever clogs could help me out with this that'd be awesome.
So, basically when i watch monoscopic 360 downloaded from youtube i always feel like i am about human size.
I want to record some 360 video (from real life) as if it's from the point of view of something smaller, e.g. a cat. Obviously i can put the camera close to the ground but that doesn't help. I still feel human size. If it was stereoscopic of course i could place the eyes closer together but i feel like there's something i'm missing that determines the viewer scale in monoscopic 360. Something in the camera settings?
for example - an ant standing on a box looking at a football (with one eye open) doesn't experience it as the same size as i do if i lie on the floor and look at it with one eye open. What's the difference in terms of 360 camera setup?
Thanks!