Thought exchange by "brainwave" is wonderful, even if we still need a little speech as auxiliary.
"It was a sort of second-sight—what they call a brainwave," Nick smiled.
brain wave n. A rhythmic fluctuation of electric potential between parts of the brain, as seen on an electroencephalogram.
A sudden useful idea; brainstorm: Lou had a brain wave. He offered the boy a C note to let him drive (1890s+)