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:The pulvinar and much of the thalamus are centres of high-order (cortical to cortical) relay connections and their activation in early hypoglycemia may reflect arousal-enhanced relay of integrated sensory information to other cortical areas (reviewed by Sherman, 2007).
Category: