Shankar B. Sachidhanandam, Institute of Physiology, University of Bern: “ Representation of sensory stimuli and mismatch in the mouse posterior parietal cortex”

Abstract:

We generate expectations of sensory stimuli through associative learning, enabling us to build a reliable internal model of the world around us. Deviations between sensory feedback stimuli and our predictions of the outside world evoke mismatch responses, allowing us to update our expectations. The mechanisms behind sensory feedback mismatch and prediction formation however remain unclear. Here we created a learned association of an auditory tactile stimulus sequence in mice and show that neurons in the posterior parietal cortex can report mismatches in the sequence, as well as display neural correlates of expectation. We demonstrate that top-down feedback from premotor cortex M2 can modulate these responses and illustrate how local inhibitory neuron circuits can participate in sensory association and mismatch generation. Finally, we show how sensory mismatch signals are differentially modulated by uncertainty, within the framework of predictive processing.