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:Given that normal hippocampal functioning is essential for both episodic AM and everyday memory (Vargha-Khadem et al., 1997; Isaacs et al., 2000), we also examined the effects of age and sex on everyday memory in order to determine whether
the results would be similar to those observed in episodic…
Category: