The ultimate goal of the human brain is to build models of the world that promote efficient and
beneficial behaviors. Perception, attention, executive control and ultimately memory provide a glimpse
into the information gathering the brain is constantly doing to build and refine these internal models.
Our research is focused on understanding cognition from this perspective and we have used memory
encoding and consolidation as a vantage point on these processes. Our lab seeks to address this
fundamental question using an interdisciplinary approach informed by the theories and methods of
Psychology, Cognitive Neuroscience and Systems Neuroscience using a diversity of methods,
including fMRI, magnetoencephalography (MEG), intracranial EEG, patient studies and real-world
studies of memory ‘in the wild’. Importantly, neural measures are primarily coupled with behavioral
readouts to allow closer inferences about human cognition, the ultimate goal of the work.
Below we detail four major lines of current research in our laboratory – on memory consolidation, how
the interplay between event perception and episodic memory supports memory organization, building
knowledge structures in the brain through experience and, finally, improving memory function.
Memory Consolidation
Less than 20 years ago, the lion’s share of work in the cognitive neuroscience of memory, including our own, examined neural activity during an experience (encoding time) or during memory retrieval. Using the subsequent memory effect, whereby trials were sorted by indices of memory behavior, this approached revealed was pivotal in revealing a network of brain regions where encoding activity predicted successful encoding or retrieval.
What is an ’episode’ in episodic memory? Role of context and event segmentation in the organization of memory
Another distinct line of work that we have spent a number of years developing focuses on the interactions between memory and perception/cognition that serve to organize our memories. One way of thinking about this question (and indeed the one that inspired our thinking on the topic) is to ask what constitutes an ‘episode’ in episodic memory? We have pursued this question using definitive assays of episodic memory, fMRI and MEG.
Building Knowledge
Both of these ongoing lines of work are related to how an individual memory (or several memories from a session) are initially coded during the experience and become strengthened through offline replay mechanisms. An important function of the memory system, however, is to encode aspects of our experiences that are novel or break our prior expectations. In this way, the ability to encode details of our daily lives serves to identify when updating of our knowledge is needed and to support knowledge updating.
Improving Memory
With these foundational insights into basic mechanisms of memory consolidation and knowledge building we can now begin to apply these insights to the important endeavor of improving learning and memory in the real world. Our lab has tackled this so far in two ways: the first is examining the impact of experimental manipulations on the durability and quality of memory. These include the impact of differential forms of attentional or goal states, emotion, reward and agency.
References
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