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:Posterior putamen has previously been shown to be involved in habitual behavior [40,41,48], and the current result indicates that, following Pavlovian cues, more chronic AD patients activate habit pathways, which confirms the habit formation theory [5].
Category: