Welcome, researchers!

Research at our laboratory concerns fundamental issues regarding human memory processes and structures. One line of this research explores the interplay between attention and memory, with the intention of determining the role of attention as a part of Working Memory in encoding and retrieval processes. Another line of research investigates the mechanisms responsible for the adult-age changes in episodic memory. Finally, we are also interested in questions relating to the role of memory processes in real-life settings, including the relationships between the acquisition and retention of knowledge.

Adult-age changes in episodic memory

A major line of our research investigates the decline in memory efficiency that comes about with age. A major empirical and theoretical effort in our research over the years has been to understand age-related changes in encoding and retrieval processes. Recently, we have suggested an associative deficit framework that attributes an important part of age-related changes in episodic memory to the deficiency of older adults in creating and retrieving links between individual units of information. In recent studies we have shown that older adults can encode and retrieve the components of an episode reasonably well, but have problems in merging those components into a cohesive unit. In our current research, we are trying to provide convergent validity to this hypothesis, as well as discriminant validity, by contrasting and testing competing predictions made by the associative deficit hypothesis and by alternative hypotheses. Our plans are to further test specific predictions made by this hypothesis, as well as to identify the brain correlates associated with this deficit.

The interaction of attention, Working Memory and long-term memory

For several years now, we have been investigating the role of attention in memory processes and memory outcomes. Originally, this research focused on encoding processes, and the results showed complex relationships between the amount of attention paid at encoding and later memory performance. Recently, we have extended this research to memory retrieval processes and showed, together with our collaborators, that there are marked asymmetries between these processes and the processes of encoding. In particular, the damaging effect of withdrawal of attention is much greater at encoding than at retrieval. This suggests that “attentional resources” are needed during the learning of new information, but are less necessary during retrieval. Nonetheless, retrieval processes do exact a performance cost on the secondary task in a dual-task situation, so retrieval cannot be "automatic" as suggested earlier by several researchers.

Our view over the years has been that to understand encoding and retrieval processes, one must isolate their basic components. To this end, we have used online measures of performance to learn about the component processes of encoding and retrieval and to relate them to memory outcomes. In recent years, we have implemented this approach using secondary tracking tasks that allow temporal micro-level analysis, which permits the identification of several basic component processes at encoding and retrieval. These basic components, and the characteristic attentional costs associated with each, seem to predict both the patterns of vulnerability of encoding and retrieval to disruption in divided attention tasks, and the attentional costs incurred in these tasks. We are presently conducting further research along these lines, with the aim of generalizing this approach to normal subjects, as well as to other populations, including the aged and people who have suffered from brain damage.