Moment-to-moment fluctuations in neuromodulatory brainstem arousal systems (e.g., dopamine and noradrenaline systems) can show large effects on learning and memory. Dopaminergic projections to the hippocampus play an important role in the formation of long-term memories. For example, previous studies have employed a reward anticipation manipulation during memory formation, eliciting dopaminergic responses in the midbrain and subsequently enhancing the encoding of memories. Until now, the origin of these dopaminergic projections has been attributed to the ventral tegmental area/substantia nigra (VTA/SN). However, growing evidence from animal studies points to the locus coeruleus (LC) as playing a key role in dopaminergic memory consolidation. In two separate experiments, we investigated the relationship between pupil size (an index of arousal; Experiment 1) and the BOLD responses of ascending arousal system nuclei (Experiment 2) and their effects on reward-related hippocampal long-term memory. In both experiments, in one-day-delayed memory tests, participants showed improved memory for neutral items that were predictive of a reward compared to neutral items that had no reward association. Pupil size was stronger for reward predicting items, indicating a successful reward anticipation response, but was not linked to subsequent memory. In line with prior work, reward anticipation elicited VTA/SN activation while later remembered items were associated with activity in the hippocampus. We will present ongoing analyses exploring i) whether a broader network of neuromodulatory nuclei (including the LC) play a role in reward associated subsequent memory effects and ii) which hippocampal subfields support these reward-related memory benefits.