Atharva Joshi supervised by Dr. Vishnu Sreekumar received his  Master of Science –  Dual Degree in Computer Science and Engineering  (CSD). Here’s a summary of his research work on Behavioral and neural evidence for temporal context retrieval during continuous recognition:

Memory allows us to store and recall past experiences, and understanding how this works is key to uncovering the mechanisms behind human cognition. This thesis investigates how temporal context —the background of experiences surrounding a memory — influences recognition in a continuous recognition task. Unlike traditional memory studies that rely heavily on free recall, this research uses the Natural Scenes Dataset (NSD) and functional MRI (fMRI) data to explore how the brain retrieves and uses temporal context. The Temporal Context Model (TCM) suggests that when we remember something, we also bring back the contextual backdrop of that memory. This study tests whether such context retrieval occurs in a continuous recognition task, where participants viewed thousands of images and indicated whether they had seen them before. The dataset’s randomized image presentation ensured minimal strategic recall, making it an excellent environment to examine authentic context retrieval effects. Results show a clear pattern: participants were more likely to correctly recognize an image if it followed another image seen in close temporal proximity. This suggests that when a memory is triggered, the brain retrieves not just the image but also the surrounding temporal context. The closer the images were during encoding, the stronger this effect — a concept known as the temporal gradient. Neural analysis further supports these findings. fMRI data reveal heightened neural similarity in the medial temporal lobe (MTL), particularly in the hippocampus and entorhinal cortex, when recognition was successful. These regions showed patterns consistent with temporal context reinstatement, confirming their central role in memory retrieval. This study contributes compelling evidence that temporal context retrieval is a fundamental aspect of episodic memory, even in scenarios without explicit recall strategies. The findings also provide insights into how the brain’s memory systems work together. Future research could build on these results by exploring how context retrieval operates across different memory tasks or using computational models to further refine the TCM. Ultimately, this study advances our understanding of how we remember our past, offering a clearer picture of the cognitive and neural foundations of memory.

August 2025