Ecological validity of don't remember and don't know for distinguishing accessibility- versus availability-based retrieval failures in older and younger adults: knowledge for news events.

With pursuit of incremental progress and generalizability of findings in mind, we examined a possible boundary for older and younger adults' metacognitive distinction between what is not stored in memory versus merely inaccessible with materials that are not process pure to knowledge or events: information regarding news events. Participants were asked questions about public events such as celebrity news, tragedies, and political events that were widely experienced in the previous 10-12 years, responding "I don't know" (DK) or "I don't remember" (DR) when retrieval failed. Memories of these events are relatively recently acquired in rich, naturalistic contexts and are likely not fully separated from episodic details. When retrieval failed, DR items were recognized with higher accuracy than DK items, both immediately and 2 years later, confirming that self-reported not remembering reflects failures of accessibility, whereas not knowing better captures a lack of availability. In fact, older adults distinguished between the causes of retrieval failures more precisely than younger adults. Together, these findings advance the reliability, validity, and generalizability of using DR and DK as a metacognitive tool to address the phenomenological experience and behavioral consequences of retrieval failures of information that contains both semantic and episodic features. Implications for metacognition in aging and related constructs like familiarity, remembering, and knowing are discussed.

Using the phenomenology of memory for recent events to bridge the gap between episodic and semantic memory.

Public events such as celebrity news, tragedies, and political events are widely experienced. Initially at least, memories of these events are "episodic" in nature; however, these events are also stored in associative networks similar to the semantic organization of knowledge (N. R. Brown, 1990, Journal of Experimental Psychology: General, 119[3], 297-314). Thus, these memories provide a novel way of examining how episodically experienced events might become semanticized and integrated into the knowledge base. Younger and older adults rated their subjective memory strength for and answered questions about details of events occurring over the previous 12 years. Participants also rated their phenomenological experience using a modified remember/know paradigm, in which no instructions about usage of the terms were provided. Interestingly, remembered and known items were equal in terms of subjective strength. Know responses were highly accurate, and more so than remember responses. Older and younger adults performed similarly. Participants' own definitions of remember, know, and just familiar revealed that knowing is associated with retrieval from semantic memory, whereas remembering and just familiarity are more associated with event/episodic memory. These results suggest that memory for public events shares phenomenological features with both episodic/event memory and semantic memory. Public events thus allow researchers to examine the complex ways in which storage of novel information can be jointly maintained in both episodic and semantic memory.