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:…even after the sensory input has been restored with CI technology, CI users show higher cross-modal activation in both visual and auditory cortex compared to normal hearing (NH) controls (Chen et al., 2016; Giraud et al., 2001a; Giraud et al., 2001b; Sandmann et al., 2012; Stropahl et al., 2016).
Category: