I was talking with a friend about sci-fi stories trying to come up with scientifically plausible mechanisms for telepathy. Like an alien species that could communicate via thoughts.
They could probably utilize some band of the EM spectrum that humans can't perceive. They would need a receptor organ to receive transmissions, and some physical transmitter for creating the transmissions.
We realized that if there were a deaf alien species, one that could not perceive soundwaves as stimuli, then our talking would be basically telepathy to them. Like if a species evolved in the vacuum of space, or on a planet lacking atmosphere, it would have no use for auditory sensations.
It might see us flapping our mouth holes, or it might feel the vibrations we make passing air across specialized muscles to create radio wave frequencies, but it would be indecipherable without a Wernicke's area of the brain to convert EM wave vibrations into thoughts. If it tried to recreate those vibrations, it would lack the Broca's area of the brain to convert thoughts into EM waves.
We always assume language would be the barrier between intelligent species, but our form of communication might be just as foreign and fantastical to them as telepathy is to us.