Abstract
<p>Do prospective memory (PM) reminders support intentions in a duplicative manner that preserves internal maintenance, or in a substitutive manner that reduces internal maintenance when a trusted external store is available? We tested this in a student population (N = 320) by crossing PM reminder reliability (0%, 50%, 100%) and availability (present vs. absent). Thought probes served as a real-time proxy for whether the intention remained in conscious awareness during the retention interval between encoding and retrieval. In Session 1 (trust trials), reminders enhanced performance without reducing PM-related thoughts, consistent with duplicative support. However, after experiencing reliable external support, Session 2 (critical trials) showed that those in the 100% condition reduced PM-related thoughts, redistributed attention to the ongoing task, and showed reduced PM retrieval when reminders were unexpectedly withdrawn. These findings suggest that trusted reminders may influence how intentions are actively maintained and prioritized during the retention interval, providing a lens for observing how memory adapts to changing external support.</p>