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 the CA1 subfield predominates in the anterior hippocampus but extends throughout its antero-posterior axis, the specific role of CA1 structural damage in episodic encoding deficits evidenced here in aMCI is therefore consistent with both hypotheses of an anterior (Lepage et al., 1998) and an antero-posterior (Schacter and Wagner, 1999) in se rm -0 06 42 17 6, v er si on 1 21 N ov 2 01 1
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