Human single-neuron activity during conscious perception and prediction in the medial temporal lobe

It remains unclear how individual neurons in the human medial temporal lobe respond during conscious perception under challenging conditions and how they signal mismatches between predictions and sensory input. To address these questions I will present ongoing work using single-neuron recordings from neurosurgical patients implanted with depth electrodes combined with eye-tracking.In the first study stimuli are presented at varying eccentricities in the visual periphery. Subjects fixate centrally and report perceived concepts allowing us to compare neural responses to detected versus undetected stimuli and across different levels of detectability.In the second study we explore prediction and prediction error signals by having subjects predict peripheral stimuli before saccading to them. On some trials images are swapped during the saccade creating a mismatch between prediction and perception.Our preliminary analyses are exploring whether human concept cells respond to different levels of detectability in a graded or an all-or-nothing manner. Additionally we observe neurons whose firing rates differ when a specific image appears after a swap versus without a swap potentially reflecting prediction error signals.

Nora Krenn est invitée par Michael Pereira.