<p>Bidirectional connectivity between the prefrontal cortex (PFC) and the medial temporal lobe (MTL) is critical for higher cognitive function, particularly within domains that are impaired with advanced age. Hyper- and hypo- excitability have been observed in both the PFC and MTL, indicating these structures are vulnerable to age. However, the link between age-related cognitive decline and functional connectivity between these regions is not yet fully elucidated. Therefore, we utilized young (4 mo) and aged (24 mo) rats that were trained to equivalent performance on a biconditional association task that depends on the PFC-PER circuit to investigate this. Our previous work demonstrated changes in signaling within the perirhinal cortex (PER) of the MTL as well as the prelimbic cortex (PL) in the PFC. These analyses focused on a subset of neurons projecting from the PER to the PFC, through the utilization of a non-toxic retrograde tracer. Age-related changes in activity levels were most evident within PER projection cells, suggesting such long-range projections experience age-related vulnerability. The present study aimed to further elucidate age-related neural signaling changes by investigating patterns of <em>Arc</em> expression within aged PL neurons and whether altered patterns of <em>Arc</em> expression were more evident specifically within PER-projecting cells. Ultimately, we determined PL neurons do undergo age-related reductions in activity, as demonstrated by reduced <em>Arc</em> expression. Importantly, such reductions are equally likely in both PER projecting and non-projecting PL neurons, a finding that suggests the vulnerability previously demonstrated by projecting neurons in the PER may be unique to that brain region.</p>