Brain and Memory Lab

ABOUT US

The Brain and Memory Lab is a part of the Oregon Memory Group, a collection of labs at the UO Department of Psychology that is interested in human memory and its interactions with attention, learning and decision making. Memory allows us to use past experiences to navigate novel situations and inform future decisions. Because every event is unique, we need to use memory flexibly, drawing upon multiple relevant experiences to anticipate future judgments. Brain and Memory Lab studies how memories are formed and how they are linked to each other to create internal representations of the world that can guide our behavior. We investigate how different memory systems are implemented in the brain, how they represent information, and how they interact. In the quest for discovery, we rely on computer-based experiments, cognitive models of behavior, and advanced functional MRI methods.

OUR RESEARCH

Memories are not just rigid records of past events. Memory is inherently constructive, fluidly deriving new knowledge by combining information from many learning experiences. The results are complex memory representations, such as schemas, mental models, and concepts, that transcend direct experience to guide novel behaviors.Our research focuses on the constructive nature of memory, in the domains of category learning and episodic memory. We use behavioral experiments, high-resolution neuroimaging, and pattern-information analysis of fMRI data to elucidate how the hippocampus and other memory systems interact to support the flexible use of experience.

CATEGORY LEARNING

Concepts—such as a concept of a dog—are mental representations of a category of things that have something in common. Category learning is the process during which we extract characteristic features of a concept, which allows us to then categorize new entities as either belonging to a category (“this is a dog”) or not. Category learning has been traditionally thought to be independent of the hippocampus, and rather rely on other memory systems, such as striatum. However, this dissociation between episodic memory and categorization is necessary an oversimplification. We are interested in how hippocampus interacts with other learning systems during category learning, to balance the need to remember distinctive details of individual events with the need to find commonalities and generalize across experiences.

Episodic memory critically dependent on structures within medial temporal lobe, especially the hippocampus. Recently, we started to learn how hippocampus interacts with prefrontal structures to support the flexible use of experience beyond memory for individual events. One way to derive new knowledge is by retrieving multiple individual memories related to the current question of interest and using logical reasoning to infer information that has not been directly observed. Such on-demand inference during retrieval relies on hippocampal interactions with a lateral part of prefrontal cortex called inferior frontal gyrus. We can also reactivate prior knowledge while experiencing new events. This way, the old reactivated memory becomes a part of the new memory, as if we experienced everything at the same time. To create such integrated memories, hippocampus interacts with ventromedial prefrontal cortex, a region that may represent generalized schemas of everyday experiences.