Our Research
Dr. Melanie Sekeres' research investigates the neural correlates of memory using a cross-species approach.
Our research takes a cross-species approach to understanding how the brain creates episodic memories (memory for the ‘what, where and when’ of an event), and how these memories transform over time. We investigate the networks of brain regions involved in memory formation, reorganization, and storage (systems consolidation), and the underlying molecular mechanisms and plasticity factors that regulate memory stabilization (synaptic consolidation) in the healthy brain, and in brains with damage to the medial temporal lobes.
​
The hippocampus is known to be a critical brain structure involved in the acquisition and initial consolidation of memory. My research has shown that soon after memory acquisition, memories tend to be detailed and precise. Over time, however, memories tend to lose some of that detail and precision, and what is retained is a more generalized version of the memory. As this occurs, the memory network reorganizes in the brain, with distributed regions in the cortex becoming increasingly involved in supporting storage and retrieval of the memory. As the memory becomes supported by the cortex, the hippocampus becomes less critical in supporting these processes.
​
In the healthy brain, the physiological mechanisms mediating this transformation of a detailed hippocampus-dependent memory to a more generalized hippocampus-independent memory are not well understood. I use a combination of gene expression techniques in rodents, and functional magnetic resonance imaging (fMRI) in humans to determine precisely how broad networks of activity change as memories age and transform over time. My research has also demonstrated how enhancing neuronal plasticity in the hippocampus, including enhancing expression of the transcription factor CREB, can enhance memory consolidation and maintain precision of even very old memories. This points to a neuronal plasticity mechanism that may be further investigated as a means of promoting memory retention, and protecting against memory decline as memories age.
​
I am currently extending my research program to study how certain factors, including exercise and environmental enrichment, promote cognitive function, memory retention, and synaptic plasticity in the aging brain. While these areas of research aim to understand the mechanisms underlying memory processing in the healthy brain, they have applications for understanding memory dysfunction associated with abnormal aging, and in response to chemotherapeutic drugs.
​