What do you mean line? Isn't the purpose of advertising to manipulate? It manipulates your emotions, you form attachment to certain products, you encode them so that they're easily recalled, they burn into you brand recognition. But there's a hell of a lot more going on than what you see on a billboard or computer/TV screen.
A good first step would be to check out
Edward Bernays - Propaganda to see how much goes into developing desire in people so that they feel that they wanted things themselves. The way we form our opinions and desires are very social and so you need to consider the way in which social relations and beliefs impact not only your subjectivity but your concrete behaviour.
Though it seeks to theorize how to stop genital mutilation in some countries,
this piece does a great job outlining theorizing about social norms and beliefs and how they interact to create change.
Such understanding readily transcribes to advertising and getting people to buy shit.
But I think with the word manipulation it might have a stronger sense of something being intentional, in which case many things are intentionally constructed to propel people to certain ends but there's a lot of conflicting interests trying to have their way. So, if considering intentions murkies things, it could be better to just think of influences/forces upon your person that impact you and shape your behaviour.
But it is of some concern the extent to which the proliferation of technology has us so saturated in invasive messages than ever before. Its so extensive that there's no games about brand, logo and slogan recognition because people know companies and their shit so well.
To think of how influential somethings are, I sometimes reflect on how I know about things that I've done absolutely nothing to actively seek out. You hear shit about celebrities and products and you didn't even have to try and find them, because they find you.
And when it comes to add, though they can be explicit in someways in order to appeal to a particular demographic, because they know who they're trying to sell shit to, they can also benefit from ambiguity. So that a person can project certain meanings into them in the same way that a person projects their personal meanings into a song, because what often gives things meaning are derived from that which is in a person's own experiences and subjectivity.
And as an extra piece, although I think it doesn't do justice to trying to theorize about objectification, here is a
good piecein considering advertising. From memory it relates well to my last part about the sort of meaning people put into things.
https://www.ethicalpolitics.org/ablunden/pdfs/For%20Ethical%20Politics.pdf#page90
-For Ethical Politics