It may not be proven but I think horses can and do recognize people. Form what I have seen after interacting with school horses and my own horse, privately owned or limited "owner like" contact, the horse is going to better recognize and bond. With the school horses, they are going to react, I think, more to the kind words and excessive treats more so than any single person.
Still, horses recognize kindness and also recognize unkindness. We know that a horse that has been abused in the past may never bond to even the kindest of humans or may be afraid of one gender or another depending on who the abuser was. For example, when I got my very first horse, I boarded at a barn with a very kindly gentleman, the typical wizened older type. He loved horses and was very good with them. This one mare, however, had been badly abused in her past. While this barn owner and trainer could hold her, he said it took 2 years, by the halter, she was always testing to see if she could pull away. She wasn't crazy afraid of people but she wouldn't "talk" to people or accept treats from anyone other than her owner. Too bad..she was a sweetie otherwise and could jump a pole held up over the heads of two 6' men from a very easy canter..this mare had springs on her feet. If I hadn't seen it I would never have believed a horse would jump over something she could have more easily walked under. The owner let me ride her once and her extended trot was like sitting in a chair; there was absolutely no bounce but even though I was kind to her she would never come to me to the front of her stall or accept a treat.