Extended Data Fig. 10: Proposed cellular and circuit mechanisms for perceptual tactile detection.
From: Active dendritic currents gate descending cortical outputs in perception
Downstream targets of PT and IT neurons are shown in different brain structures. When a stimulus reaches the suprathreshold intensity, Ca2+ spikes are selectively activated in the apical dendrites of PT neurons in S1 (45.7% of PT dendrites versus 9.5% of IT dendrites). The activation of dendritic Ca2+ spikes is strongly dependent on inputs to the distal apical dendrites carrying contextual information. Ca2+ spikes trigger bursts of high-frequency somatic APs6,7. Boosted AP outputs of PT neurons are broadcasted to subcortical regions, with a critical involvement of higher-order thalamus, superior colliculus, and striatum, for the subsequent perceptual process or motor action (for example, licking). Thus, dendritic Ca2+ spikes drive context-dependent interactions between cortex and subcortical structures that are crucial for perceptual tactile detection.
