Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:…a 15-mm sphere functional ROI for dorsal pons [2 30 32] was derived from previous work demonstrating its sensitivity to first order representations of bodily state (Critchley et al., 2001), implicating it in anger processing (Damasio et al., 2000) and core aspects of emotion (Damasio, 2010).
Category: