We also showed that monkeys were able to wait for their turn depending on the decisions of the experimenter: a special kind of turn taking behavior. Turn-taking develops early in human infants and develops furthermore later [30,31], and it is based at least on the abilities to distinguish self from others and to monitor others’ goals and their accomplishment. We believe that our results have relevance beyond behavioral research. Our results point to the possibility of using H–M paradigms in other fields of neuroscience. The H–M paradigm can represent a complementary approach to the monkey–monkey (M– M) paradigm that has gained prominence recently, offering new possibilities for controlling the parameters of the interaction. This could be done, for example, by using the human partner as an independent variable that can be manipulated in the study in a way that is much easier than manipulating a monkey partner. 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Adolphs R (2010) Conceptual challenges and directions for social neuroscience. Neuron 65: 752–767. PLoS ONE | www.plosone.org 5 February 2012 | Volume 7 | Issue 2 | e32209