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 hippocampus and other memory systems interact to support the flexible use of experience. Memory integration. Episodic memory is memory for events in our lives, such as remembering how you saw a squirrel on your last walk in the park. Individual events are not isolated from each other, but rather share elements such as people, places, and objects they have in common. These shared elements provide means to integrate individual events to networks of related memories, at the basis of complex knowledge representations such as schemas and cognitive maps. 
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. Sample publication: Zeithamova, D. & Dominick, A.L., Preston, A.R. (2012). Hippocampal and ventral medial prefrontal activation during retrieval-mediated learning supports novel inference. Neuron, 75(1), 168-79. PDF 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.
Sample publication: Bowman, C.R.& Zeithamova, D. (2018). Abstract memory representations in the ventromedial prefrontal cortex and hippocampus support concept generalization. Journal of Neuroscience, 2811-17. PDF