Travis helped Carlos work on his car. In return, Carlos helped Travis learn some guitar chords. Travis didn't expect to get some extra guitar help, but now Travis is inspired to help Carlos again, since it seems Carlos always returns a favor. What does this situation describe

Paradox of altruism

Explanation:

Paradox of altruism is seen as a scenario where one person's help becomes a favourable thing for an individual and the individual picks interest in the help and wants to know more of it. Most paradox of altruism cases are not predicted as both individuals don't really plan on how it will all happen until it happens. Travis and Carlos situation describes paradox of altruism, where they helped each other and it turned out favourable to help themselves more.

she recieved a treatment not thought to be specifically effective in treating her disorder.