Title : Role of hippocampus in sensory memory: Analyzing neural firing responses in mice during a visual change detection task

The hippocampus is essential for memory storage, particularly in long-term memory formation. However, insufficient information exists to know its function in sensory memory (< 1 sec), which is the focus of this study. Sensory memory is widely studied regarding the responses in cortical regions (for example, visual cortex, VIS), but simultaneous comparison of hippocampal and sensory cortical activity is lacking. To address these issues, extracellular spiking responses of single neurons from the hippocampus (specifically sub-region CA1) and primary visual cortex (VISp) were analyzed while the subjects (mice) performed a delayed change detection task, using a publicly available dataset from the Allen Brain Institute. We hypothesized that the population activity in the hippocampus and visual cortex is modulated differentially, and together, they help the mouse perform a non-spatial, delayed change detection task. Jupyter Notebook and Python coding were used to analyze these neural recordings and the accompanying behavioral metrics. Correlation coefficients and firing rate responses of neurons were compared between CA1 and VISp, as well as other brain regions. The results indicate that CA1 population responses had consistently high correlation values above 0.90, representing stable neural activity; they peaked immediately after an image change and remained elevated more than the omitted (no stimulus) conditions. Additionally, during behavioral responses, the licking and reward frequency correlated with hippocampal activity. These findings suggest that the hippocampus processes sensory information, displays varied responses during correct and incorrect trials in a sensory memory task, and, combined with the visual cortex, aids mice in performing the task.

Archit Sonaje is an undergraduate student at the University of California, Los Angeles, pursuing a degree in Computational Biology. His research interests include computational neuroscience, bioinformatics, and the molecular mechanisms underlying neurological disorders. He has conducted research on hippocampal sensory memory using mouse neural recordings through work with UCSF and investigated molecular pathways associated with alcohol use disorder through miRcore’s Genes in Diseases and Symptoms (GIDAS) program. He has presented his research at scientific conferences and contributed to research manuscripts. He is particularly interested in applying computational and data-driven approaches to advance neuroscience and disease research.