'displays of emotion'

If an individual's discourse-use within a group 'is accompanied by displays of emotion'  that correspond to that group's emotion, 'then that individual will be judged to be a "cooperator"...and group members will predict further cooperative behavior from that individual in relation to [their] group (adapted from Bubulia and Sosis, 2011, 365; cf. Irons 2001)'.

XJ, pp. 94-95 (adapted)