Thanks for your question! Apart from Segments, nothing gets shared between AAM and Target. The audience qualification happens on our edge infrastructure. Once the audience and the activity qualifications happen on edge, edge responds back with content to the end user. The end user's web page happening to be an AEM page at this point is incidental. We are not sending this info to AEM.
Thanks for your follow up! This blog post on Audience Manager segments might be helpful in clarifying the concepts you are looking to understand better. Please reach out here if you have any other related questions/ comments.