New Insights into Hippocampus Function Reveal How Our Brains Predict Visual Inputs

Recent research conducted by scientists at University College London's Queen Square Institute of Neurology has uncovered intriguing mechanisms by which the hippocampus communicates with the visual cortex to enable the brain's predictive capabilities. Utilizing ultra-high-resolution 7T functional magnetic resonance imaging (fMRI), the study investigated how different regions within the hippocampus, especially CA2/3, and the parahippocampal cortex (PHC) participate in expectancy-driven neural activity.

Participants in the study were presented with sound cues linked to specific abstract shapes. These shapes were either shown normally or omitted to observe how the brain anticipated visual stimuli. It was observed that upon hearing the sound cues, the hippocampus and the PHC exhibit distinct activity patterns that correspond to the predicted shapes. Specifically, neural activity in the hippocampus encoded expectations of upcoming images, while the patterns when shapes were omitted suggested a neural basis for prediction rather than mere response to stimuli.

The study also delved into the neural directionality of information flow. It was found that the predictions generated by the hippocampus influence the deep layers of the PHC, supporting the theory that the hippocampus actively reconstructs expected sensory inputs to aid perception. This reciprocal communication underscores the hippocampus's role beyond memory, extending into anticipatory processes vital for learning and decision-making.

Professor Peter Kok emphasized that these findings demonstrate the hippocampus's involvement in future-oriented cognition, such as predicting upcoming sensory experiences. By sending reconstructed expectations to the sensory cortex, the hippocampus helps the brain prepare for what is to come, facilitating rapid perception and adaptive behavior.

This research advances our understanding of the neural basis of predictive coding and highlights the hippocampus's crucial role in integrating memory and perception. Such insights could inform future studies on cognition, learning, spatial navigation, and the development of interventions for perceptual or memory impairments.

Source: MedicalXpress