What is the importance of eye and ear cues in attention and communication of racehorses and ponies and do they react in a similar way to humans?

Project title: What is the importance of eye and ear cues in attention and communication of racehorses and ponies and do they react in a similar way to humans?
Overview:

Is there a difference in response to eye and ear cues between a pony and a racehorse and do similar cues apply to humans.