The only significant subsequent memory effect that was identified is located in the left hippocampus. (A) Sagittal view of the brain depicting the three different types of hippocampal effects found in comparing placebo with dexmedetomidine. The green areas represent those regions where blood oxygen level-dependent activity was greater for items that were subsequently remembered versus items that were subsequently forgotten common to both the placebo subjects and the subjects on dexmedetomidine. The red areas illustrate where there was a significant interaction, such that the placebo subjects had a larger subsequent memory effect than the dexmedetomidine subjects. Thus, this analysis identifies the red area as one neural correlate associated with the behavioral decrease in long-term memory performance that occurs on dexmedetomidine. The blue region is shown for comparison to reveal how nearby brain activity was greater for dexmedetomidine than placebo, even though this particular region did not show any subsequent memory effect. Three different close-up coronal views of the hippocampus are illustrated in the insets; (B) where the y coordinate is −10, (C) at the y coordinate of −16, and (D) at the y coordinate of −22. Images are displayed on sections of the normalized across-subjects mean anatomical image and thresholded at a minimum of P < 0.001, with a 20-voxel extent threshold.