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:…reflect early face processing mechanisms related to the structural encoding of faces (Bentin and Deouell, 2000; Bentin et al., 1996; Eimer, 2000a; Holmes et al., 2003) and has been found to be insensitive to changes in facial expression (Eimer et al., 2003; Holmes et al., 2003) or familiarity…
Category: