Cues such as smells and anticipation of social interactions can be highly reinforcing and build anticipation or craving.

“In the morning of Thanksgiving, all, for most of us in the United States, the morning of Thanksgiving, if you're at home visiting your parents, the smells of the apple pie, the smells of the turkey cooking are highly repetitive, highly reinforcing. You're anticipating that fun event. You're anticipating Uncle Joe coming to visit you for Thanksgiving. And that's all because these cues, the smells, the anticipation of Uncle Joe, your previous experiences, are part of your memory system, sort of talking to, in a simple way, your reward circuitry. So you're building up this anticipation, one could almost say this craving, which maybe we'll talk about in the context of addiction.”