That's an interesting question. The real question, if I understand you correctly, is "Do they recognize and react to eye contact, and how cognisant are they that you are making eye contact?"
I have worked,through the years, with many many different species of snakes. Some of the most alert and "intelligent" species I have ever worked with were what I call "Fast Elapids". This includes things like Mambas, Forest Cobras, Cape Cobras, Spitters, Kings, Taipans, etc. In my experience, Indigos, Coachwips, and Racers are very very similar in overall behavior.
I think snakes, especially these super-alert species, do recognize and react to eye contact. I think that point is proven out with spitting cobras. They will hit a potential threat in the eyes unfailingly.
I can recall one incident with a zookeeper (who shall remain nameless) working at a zoo (which shall also remain nameless). He was showing some personal visitors (also nameless) a Western Green Mamba in the keeper's alley during zoo hours. It wasn't a particularly large specimen, maybe 5 feet long. This thing managed to get away from him in the keeper's alley while he was showing it (which immediately put all of his personal visitors on high alert), and landed on the floor in front of him. What ensued for the next several seconds can only be described as a 4-way staring contest. This keeper had inadvertently left the door to the keeper's alley cracked open a little. This door led directly into the viewing area which was full of zoo visitors at the time. The keeper glanced at the keeper's alley door and it was like the snake saw him look at the door, looked for himself and realized the door was open and made a break for it, escaping into the viewing area. The now frantic keeper sailed out the door right behind the snake, which was now hugging the wall behind the oblivious zoo visitors. The keeper managed to grab the snake by it's tail and get back inside the door without anyone noticing what was going on. That was one alert snake.
My Indigos are very alert and seem to be capable of at least rudimentary reasoning. I haven't noticed anything that would make me believe that they necessarily react to eye contact, but I haven't paid particular attention to that either. I will from now on, though. My Indigos and Cribos all have their own distinct personalities, though. I have one big male rubidus that is as squirrely as any snake I've ever seen. He's not mean or intent on biting or anything like that, but if he realizes I'm in the room he freaks out and pour himself into his hiding box as fast as any snake you've ever seen. My other big male could care less. He knows I'm there, but just doesn't care. My big female is the same way. None of my Texans are particularly spooky, but my yearling female like to show her attitude when she sees me. My big female Yellowtail is like she's hatching the Master Plan to kill me. It's like she's thinking, "OK, if I wait just another second or two, he'll move over there and that shelf will be behind him. If I strike at his face then, he can't back up quickly enough to get away from me and I might be able to chew his head right off his shoulders. Oh, wait...he has a rat in his hand. Never mind..I'll kill him next time."
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We do not inherit the Earth from our ancestors; we borrow it from our children. Ralph Waldo Emerson