AbstractBackgroundEpisodic memory decline characterizes “normal” aging but is also a core symptom of Alzheimer’s disease. Therefore, considerable efforts have been undertaken to study this memory domain and its neural substrates. Recent studies have mainly focused on encoding‐ and retrieval‐ related processes. However, some findings suggest that episodic memory deficits are at least in part due to impaired consolidation processes.MethodsWe investigated age effects on consolidation‐related functional network changes and their vulnerability to cognitive interference, using fMRI data of 13 young (20–30 years) and 16 senior (49–75 years) participants. FMRI scanning was performed prior to and during a spatial memory paradigm, consisting of encoding, consolidation, and retrieval phases. To ensure that the observed connectivity changes were due to consolidation processes, the consolidation phase was manipulated over two sessions: (1) no manipulation and (2) repeated stimulus‐presentation with interfering spatial context information.ResultsWe compared the fractional amplitude of low‐frequency fluctuations (fALFF) to analyze spontaneous brain activity changes from pre‐ to post‐encoding rest. In the control condition, fALFF decreased within left supramarginal gyrus (SMG), right middle temporal gyrus (MTL), and left precuneus (Pc), whereas, fALFF increased within parts of the occipital and inferior temporal cortex. To evaluate the integration in large‐scale brain networks, connectivity analyses between the fALFF‐derived seeds and network ROIs were performed. We observed significant coupling between consolidation‐related brain regions and large‐scale brain networks during consolidation, with connectivity between the SMG and large parts of the memory network modulated by aging. There was also a disruptive effect of interference on connectivity between the Pc and parts of the salience network. Of particular importance for successful consolidation, however, is the connectivity between parts of the occipital lobe, the inferior and middle temporal gyrus. Connectivity within this network, which corresponds to the ventral visual stream, may predict subsequent memory performance. The predictive value appears to be higher in young than in seniors.ConclusionOur results support the assumption that age‐related memory decline is at least partly caused by impaired consolidation processes. We showed that consolidation requires a complex interplay between large‐scale brain networks, which is partially disrupted by aging and thus becomes insufficient.