Telepathic or empathic communication perhaps?

[ This actually is helping after a fashion, distracting him from his aching head and motion-sick-like feeling he's getting from needing to adjust to completely different electromagnetic radiation. This is why he dislikes teleporting - it's the rapid, sudden shift of his bearings and even if his nervous system is fast, it's an adjustment. ]

A few. The only one who seemed to struggle with the concept was a five year old child.