I think both for sure...

Funny story. Had my nest friend out this past wkend for a hunt. I set him up 100 yards in front of me in good tree cover. I was in a high tree blind too further back overlooking clearing. 7:00 am a cull buck walks right past him thru the trees towards me (no shot for him). I watched him walk and graze towards me. At full draw, waiting for 1 more step the feeder goes off at 7:15. He turns and runs back to the woods. 5 min later, buck down. I have seen this buck on property this season, so I know he knew the feeder was there. But funny story nonetheless.

I watch them every day. They can smell one kernel of corn from a long distance.

I play tricks on them with 30lb test line and corn.

I would like to think that it would be a combination of both. The ones that are used to the area and know the times when the feeder goes off are usually there before it does. The deer who aren't very familiar with the area here and it then go check it out.

This is a great question that could go both ways really, we don't actually know what the deer think. So, it's a toss up.

You fish for buck bass?

i put out pvc feeders and had dear there that night. pvc makes no sound and it was in a new random spot

Smell first. Just like a food plot. They have to smell it first. But some fawns are raised by the sound of feeders and know that candy is on the ground when it goes off, so maybe when they grow up and have fawns same thing happens. So maybe instinct also