Everyday functioning relies on episodic memory, the conscious retrieval of past experiences, but this crucial cognitive ability declines severely with aging and disease. Vulnerability to memory decline varies across individuals however, producing differences in the time course and severity of memory problems that complicate attempts at diagnosis and treatment. Here we identify a key source of v...

Aging attenuates the capacity to adaptively and flexibly use episodic memory at different levels of specificity. Older and younger adults were tested on a picture recognition task that required them to make episodic memory decisions at an item-specific (verbatim) versus category-based (gist-based) level on randomly intermixed trials. Specificity modulation was assessed using a measure of the li...

Memories for certain events tend to linger in rich, vivid detail, and retrieval of these memories includes a sense of re-experiencing the details of the event. Most events, however, are not retained in any detailed way for more than a few days. According to one theory, the hippocampus plays a specific role in supporting episodic retrieval, that is, the re-experiencing of an event as part of one...

In recent years, most studies of human memory systems have placed the emphasis on differences rather than on similarities. The present study sought to assess the impact of perceptual priming on the creation of new episodic memories. It was composed of three distinct experimental phases: (1) an initial study phase, during which the number of repetitions of target words was manipulated; (2) a per...

Episodic memory provides many important capabilities to a cognitive architecture. One of the challenges of creating a general episodic memory system is to be effective when given no information about the agent’s task. In this paper, we present an effective algorithm for detecting the relevance of the features of episodic memories while only being told when an agent completes a goal. We demonstr...

The hypothesis that episodic memory retrieval can occur in parallel with other cognitive processes was tested in 2 experiments. Participants memorized words and then performed speeded cued recall (Experiment 1) or speeded yes-no recognition (Experiment 2) in a dual-task situation. The psychological refractory period design was used: The participant was presented with a single test item at vario...

Prior semantic processing can enhance subsequent picture naming performance, yet the neurocognitive mechanisms underlying this effect and its longevity are unknown. This functional magnetic resonance imaging study examined whether different neurological mechanisms underlie short-term (within minutes) and long-term (within days) facilitation effects from a semantic task in healthy older adults. ...

In studies of episodic recognition memory, low-frequency words (LF) have higher hit rates (HR) and lower false alarm rates (FAR) than do high-frequency words (HF), which is known as the mirror pattern. A few findings have suggested that requiring a task at study may reduce or eliminate the LF-HR advantage without altering the LF-FAR effect. Other studies have suggested that the size of the LF-H...

Old age is generally accompanied by a decline in memory performance. Specifically, neuroimaging and electrophysiological studies have revealed that there are age-related changes in the neural correlates of episodic and working memory. This study investigated age-associated changes in the steady state visually evoked potential (SSVEP) amplitude and latency associated with memory performance. Par...

We used event-related functional magnetic resonance imaging (efMRI) to investigate brain regions showing differential responses as a function of confidence in an episodic word recognition task. Twelve healthy volunteers indicated whether their old-new judgments were made with high or low confidence. Hemodynamic responses associated with each judgment were modeled with an "early" and a "late" re...