Well, when I send light to someone, it is normally when they are having a bad day and need a pick me up, or I send them healing light if they aren't feeling well, or something is wrong.
When sending a pick-me-up, I normally feel like a sort of tingling in my stomach, which is really where the emotions are stored for the most part, in the lower chakras. Or I feel the emotional issues going to my head to form a headache, which the person either has from it, or this is what my body is making of their bad day.
But when sending healing light, I can feel where their pain is, and send it directly there. Depending on how severe the pain is, I send a light to heavy amount of light.
When sending to animals, it is a bit different, because they feel things differently than we do. Their pain resides in their stomachs as well, but also in their tails I have noticed-with animals that have tails, that is. Emotional issues can scatter though, many tend to get it in their paws. A slight uncomfortable feeling or pain, depending on how much of a hard time they are having.
Not sure if this really answers your question, I kind of went off, sorry.