Horsepeople always say that the short-term memory (or attention span, whatever you want to call it) is in the ballpark of three seconds, probably less. That's why corrections and rewards must be given instantaneously for the horse to make the connection between cause and effect. We laugh at and then scold the person who gets bucked off, chases her horse around for 10 minutes, then gives him a whoopin' to teach him not to buck again.
Yet now, if we tie horses up for a couple hours after riding, they'll mull the training session over in their heads, reflect on what went right and what went wrong, and plan on how to do better next time?