A Translaminar Spacetime Code Supports Touch-Evoked Traveling Waves

Linking sensory-evoked traveling waves to underlying circuit patterns is critical to understanding the neural basis of sensory perception. To form this link, we performed simultaneous electrophysiology and two-photon calcium imaging through transparent NeuroGrids and mapped touch-evoked cortical traveling waves and their underlying microcircuit dynamics. In awake mice, both passive and active whisker touch elicited traveling waves within and across barrels, with a fast early component followed by a variable late wave that lasted hundreds of milliseconds post-stimulus. Strikingly, late-wave dynamics were modulated by stimulus value and correlated with task performance. Mechanistically, the late wave component was i) modulated by motor feedback, ii) complemented by a sparse ensemble pattern across layer 2/3, which a balanced-state network model reconciled via inhibitory stabilization, and iii) aligned to regenerative Layer-5 apical dendritic Ca2+ events. Our results reveal a translaminar spacetime pattern organized by cortical feedback in the sensory cortex that supports touch-evoked traveling waves. GRAPHICAL ABSTRACT AND HIGHLIGHTS O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=66 SRC="FIGDIR/small/593381v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@c98840org.highwire.dtl.DTLVardef@1105364org.highwire.dtl.DTLVardef@d2f2c9org.highwire.dtl.DTLVardef@1418744_HPS_FORMAT_FIGEXP M_FIG C_FIG O_LIWhisker touch evokes both early- and late-traveling waves in the barrel cortex over 100s of milliseconds C_LIO_LIReward reinforcement modulates wave dynamics C_LIO_LILate wave emergence coincides with network sparsity in L23 and time-locked L5 dendritic Ca2+ spikes C_LIO_LIExperimental and computational results link motor feedback to distinct translaminar spacetime patterns C_LI